Although anal squamous cell carcinoma (SCC) and adenocarcinoma (ADC) are generally combined in cancer surveillance, their etiologies likely differ. Here, we describe demographic characteristics and trends in incidence rates (IRs) of anal cancer by histology (SCC, ADC) and behavior (invasive, in situ) in the United States.
With data from the Surveillance, Epidemiology and End Results (SEER) Program, we estimated age-adjusted anal cancer IRs across behavior/histology by demographic and tumor characteristics for 2000–2011. Trends in IRs and annual percent changes during 1977–2011 were also estimated and compared to rectal cancer.
Women had higher rates of SCC (rate ratio [RR]=1.45; 95%CI 1.40–1.50) and lower rates of ADC (RR=0.68; 95%CI 0.62–0.74) and squamous carcinoma in situ (CIS) (RR=0.36; 95%CI 0.34–0.38) than men. Blacks had lower rates of SCC (RR=0.82; 95%CI 0.77–0.87) and CIS (RR=0.90; 95%CI 0.83–0.98) than non-Hispanic whites, but higher rates of ADC (RR=1.48; 95%CI 1.29–1.70). Anal cancer IRs were higher in men and blacks aged <40 years. During 1992–2011, SCC IRs increased 2.9%/year, ADC IRs declined non-significantly, and CIS IRs rose 14.2%/year. SCC and ADC IR patterns and trends were similar across anal and rectal cancers.
Rates of anal SCC and CIS have increased strongly over time, in contrast to rates of anal ADC, similar to trends observed for rectal SCC and ADC.
Anal SCC and ADC likely have different etiologies, but may have similar etiologies to rectal SCC and ADC, respectively. Strong increases in CIS IRs over time may reflect anal cancer screening patterns.
Anal cancer; epidemiology; descriptive
Testicular germ cell tumors (TGCT), which comprise 98% of all testicular malignancies, are the most commonly occurring cancers among men between the ages of 15 and 44 years in the United States (U.S.). A prior report from our group found that while TGCT incidence among all U.S. men increased between 1973 and 2003, the rate of increase among black men was more pronounced starting in 1989–1993 than was the rate of increase among other men. In addition, TGCT incidence increased among Hispanic white men between 1992 and 2003. To determine whether these patterns have continued, in the current study we examined temporal trends in incidence through 2011. Between 1992 and 2011, 21,271 TGCTs (12,419 seminomas; 8,715 nonseminomas; 137 spermatocytic seminomas) were diagnosed among residents of the Surveillance, Epidemiology, and End Results (SEER) 13 registry areas. The incidence of TGCT was highest among non-Hispanic white men (6.97 per 100,000 man-years) followed by American Indian/Alaska Native (4.66), Hispanic white (4.11), Asian/Pacific Islander (1.95), and black (1.20) men. Non-Hispanic white men were more likely to present with smaller tumors (3.5 cm) and localized disease (72.6%) than were men of other races/ethnicities. Between 1992 and 2011, TGCT incidence increased significantly among Hispanic white (APC: 2.94, p<0.0001), black (APC: 1.67, p=0.03), non-Hispanic white (APC: 1.23, p<0.0001), and Asian/Pacific Islander (APC: 1.04, p=0.05) men. Incidence rates also increased, although not significantly, among American Indian/Alaska Native men (APC: 2.96, p=0.06). The increases were greater for nonseminoma than seminoma. In summary, while non-Hispanic white men in the U.S. continue to have the highest incidence of TGCT, they present at more favorable stages of disease and with smaller tumors than do other men. The increasing rates among non-white men, in conjunction with the larger proportion of non-localized stage disease, suggest an area where future research is warranted.
testicular cancer; TGCT; trends; SEER; incidence; ethnic groups
Incidence rates of testicular cancer in Northern European and North American countries have been widely reported, whereas rates in other populations, such as Eastern Europe, Central/South America, Asia, and Africa, have been less frequently evaluated. We examined testicular cancer incidence rates overall and by histologic type by calendar time and birth cohort for selected global populations 1973-2007.
Age-standardized incidence rates over succeeding 5-year periods were calculated from volumes 4-9 of Cancer Incidence in Five Continents electronic database (CI5plus) and the newly-released CI5X (volume 10) database. Annual percent change over the 35-year period was calculated using weighted least squares regression. Age-period-cohort analyses were performed and observed rates and fitted rate ratios presented by birth cohort.
Incidence rates of testicular cancer increased between 1973-1977 and 2003-2007 in most populations evaluated worldwide. Of note, incidence rates in Eastern European countries rose rapidly and approached rates in Northern European countries. Rates in Central and South America also increased and are now intermediate to the high rates among men of European ancestry and low rates among men of Asian or African descent. Some heterogeneity in the trends in seminoma and nonseminoma were observed in Denmark, the United Kingdom and among US whites, particularly in recent generations, with rapid and uniform increases in the incidence of both histologic types in Slovakia.
Reasons for the rising incidence rates among European and American populations remain unexplained; however, changing distributions in the prevalence of risk factors for testicular cancer cannot be ruled out.
international trends; testicular cancer incidence; birth cohort; seminoma
U.S. lung cancer incidence rates overall are declining in the United States. We investigated the trends by histologic type and demographic characteristics.
Surveillance, Epidemiology, and End Results (SEER) program rates of microscopically-confirmed lung cancer overall and squamous cell, small cell, adenocarcinoma, large cell, other, and unspecified carcinomas among U.S. whites and blacks diagnosed 1977–2010 and white non-Hispanics, Asian/Pacific Islanders and white Hispanics diagnosed 1992–2010 were analyzed by gender and age.
Squamous and small cell carcinoma rates declined since the 1990s, although less rapidly among females than males. Adenocarcinoma rates decreased among males and only through 2005, after which they then rose during 2006–2010 among every racial/ethnic/gender group; rates for unspecified type declined. Male/female rate ratios declined among whites and blacks more than among other groups. Recent rates among young females were higher than among males for adenocarcinoma among all racial/ethnic groups and for other specified carcinomas among whites.
U.S. lung cancer trends vary by gender, histologic type, racial/ethnic group, and age, reflecting historical cigarette smoking rates, duration, cessation, cigarette composition, and exposure to other carcinogens. Substantial excesses among males have diminished and higher rates of adenocarcinoma among young females have emerged as rates among males declined more rapidly. The recognition of EGFR mutation and ALK rearrangements that occur primarily in adenocarcinomas are the primary basis for the molecular revolution that has transformed lung cancer diagnosis and treatment over the past decade, and these changes have affected recent type-specific trends.
Population-based studies comprehensively describing incidence patterns of human papillomavirus (HPV)-related preinvasive and invasive neoplasms prior to widespread HPV vaccination are sparse.
We calculated age-adjusted incidence rates (IRs), IR ratios (IRRs), and annual percent changes (APC) in IRs for potentially HPV-related tumors diagnosed in the Surveillance, Epidemiology and End Results Program during 1978–2007.
Overall IRs for preinvasive tumors were significantly higher than for invasive squamous cell tumors of cervix (IRR=3.42), vulva (IRR=1.87), and vagina (IRR=1.19) and significantly lower for adenomatous cervical tumors (IRR=0.43), and squamous cell tumors of penis (IRR=0.64), anus (males, IRR=0.53; females, IRR=0.14), and head and neck (H&N) (males, IRR=0.01; females, IRR=0.02). Incidence of preinvasive squamous tumors of cervix, vagina, and penis rose rapidly over time and decreased for invasive neoplasms. The most rapid increases occurred for preinvasive (males, APC=16.0; females, APC=7.3) and invasive anal tumors (males, APC=3.6; females, APC=2.3). IR patterns were generally similar among evaluable racial/ethnic groups, with the exception of H&N invasive tumor IRs which increased exclusively among white males.
Contrary to the opposing trends of preinvasive and invasive squamous tumors of cervix, vagina, and penis, preinvasive and invasive anal tumor IRs increased significantly over time by gender, age, and racial/ethnic groups. Successful HPV vaccination programs are needed to measurably reduce incidence of HPV-related neoplasms in the future, particularly for cancer sites with rising incidence rates for which effective screening modalities are limited.
HPV-associated neoplasms; preinvasive tumors; cancer incidence; epidemiology; squamous cell neoplams
The aetiology of marginal zone lymphoma (MZL) is purported to differ by anatomic site. While this is supported by clinical series of single MZL sites, no population-based study has comprehensively assessed incidence patterns across sites. To gain insight into disease aetiology, we assessed MZL incidence by site using data from 18 U.S. Surveillance, Epidemiology and End Results (SEER) Program population-based registries. We calculated age-adjusted incidence rates (IRs) by sex, race, and calendar year. During 2001–2009, 4,081 (IR=5.7/1,000,000 person-years) and 8,821 (IR=12.3) individuals were diagnosed with nodal MZL and extranodal MZL, respectively. The most common extranodal sites were stomach (IR=3.8), spleen (IR=1.6), eye/adnexa (IR=1.4), and lung, skin, and salivary glands (IRs=0.9–1.0). We observed distinct age-specific patterns by MZL site, with IRs increasing steeply at younger ages and less prominently after mid-life at several sites, except skin. Gender and racial/ethnic disparities were also apparent across sites. Between 2001–2005 and 2006–2009, MZL IRs decreased significantly for gastric (-15%) and soft tissue (-28%) sites, whereas IRs increased significantly for lung (18%), skin (43%), and kidney/renal pelvis (116%). In combination, our findings support the contention that MZL is characterized by aetiological heterogeneity across sites and susceptibility is probably influenced by intrinsic characteristics and environmental exposures.
Marginal zone lymphoma; Incidence; Population-based study; Anatomic site; Joinpoint analysis
In contrast to the well-described epidemiology and behavior of small cell lung carcinoma (SCLC), little is known about extrapulmonary small cell carcinoma (EPSCC).
Using data from the Surveillance, Epidemiology and End Results (SEER) Program (1992–2010), we calculated age-adjusted incidence rates (IRs), IR ratios (IRRs), annual percent change (APC), relative survival (RS), RS ratios (RSRs), and the respective 95% confidence intervals (95% CI) of SCLC and EPSCC according to primary site. We used the SEER historic stage variable that includes localized (confined to the organ of origin), regional (direct extension to adjacent organ/tissue or regional lymph nodes), and distant (discontinuous metastases) stages and combined localized and regional stages into “limited” stage.
The incidence of SCLC (IR = 76.3/million person-years; n = 51,959) was 22-times that of EPSCC (IR = 3.5; n = 2,438). Of the EPSCC sites, urinary bladder, prostate, and uterine cervix had the highest incidence (IRs = 0.7-0.8); urinary bladder (IRR = 4.91) and stomach (IRR = 3.46) had the greatest male/female disparities. Distant-to-limited stage site-specific IRRs of EPSCC were significantly elevated for pancreas (IRR = 6.87; P < 0.05), stomach, colon/rectum, ovary, and prostate (IRRs = 1.62-2.42; P < 0.05) and significantly decreased for salivary glands, female breast, uterine cervix, and urinary bladder (IRRs = 0.32-0.46). During 1992–2010, significant changes in IRs were observed for EPSCC overall (APC = 1.58), small cell carcinoma of the urinary bladder (APC = 6.75), SCLC (APC = −2.74) and small cell carcinoma of unknown primary site (APC = −4.34). Three-year RS was significantly more favorable for patients with EPSCC than SCLC for both limited (RSR = 2.06; 95% CI 1.88, 2.26) and distant stages (RSR = 1.55; 95% CI 1.16, 2.07). Among limited stage small cell carcinoma, RS was most favorable for salivary glands, female breast, and uterine cervix (RS = 52-68%), whereas RS for nearly all sites with distant stage disease was <10%.
EPSCC comprises a heterogeneous group of diseases that appears, at least in part, etiologically distinct from SCLC and is associated with more favorable stage-specific patient survival.
Electronic supplementary material
The online version of this article (doi:10.1186/s12885-015-1188-y) contains supplementary material, which is available to authorized users.
Extrapulmonary small cell carcinoma; Small cell lung cancer; Epidemiology; Incidence; Survival
We evaluated incidence patterns of biliary tract cancers (gallbladder, extrahepatic bile duct, ampulla of Vater, and not otherwise specified) to provide potential insight into the etiology of these cancers. Data were obtained from the population-based Surveillance, Epidemiology, and End Results (SEER) program. Rates for cases diagnosed during 1992–2009 were calculated by racial/ethnic, gender, and age groups. Temporal trends during 1974–2009 and annual percentage changes (APC) during 1992–2009 were estimated. Age-adjusted rates by site were higher among American Indian/Alaska Natives, Hispanics (white) and Asian/Pacific Islanders (Asian/PI) and lower among whites and blacks. Gallbladder cancer was more common among women in all ethnic groups (female-to-male incidence rate ratio [IRR] ranged from 1.24 to 2.86), but bile duct and ampulla of Vater cancers were more common among men (female-to-male IRR 0.57 to 0.82). Gallbladder cancer rates declined among all racial/ethnic and gender groups except blacks (APC −0.4% to −3.9%). In contrast, extrahepatic bile duct cancer rates rose significantly in most female racial/ethnic groups; the APCs among whites were 0.8 among females and 1.3 among males, both significant. Rates for ampulla of Vater cancer decreased among Asian/PI females (APC −2.7%) but remained stable for the other groups. In addition to confirming that biliary tract cancer incidence patterns differ by gender and site, and that the gallbladder cancer incidence rates have been declining, this study provides novel evidence that extrahepatic bile duct cancer rates are rising. These observations may help guide future etiologic studies.
biliary tract cancer; gallbladder cancer; extrahepatic bile duct cancer; ampulla of Vater cancer; Klatskin tumors; incidence
To determine the incidence of testicular germ cell tumors among active duty males and compare it with the incidence in the general U.S. population.
The Automated Cancer Tumor Registry and the Surveillance, Epidemiology, and End Results Program data from 1990 to 2003 were analyzed for men aged between 20 and 59 years by histology and stage at diagnosis. Rates were age adjusted using the male active duty military population as the standard.
Nonseminoma incidence was significantly lower in the military than in the general population (incidence rate ratio = 0.90, 95% confidence interval = 0.82-0.98). Trends in incidence tended to be similar in both the populations. Increases were observed for both histologic types but were only significant for seminoma (Automated Cancer Tumor Registry: 21% and Surveillance, Epidemiology, and End Results program: 16%; p < 0.05). Increases in incidence were only observed for localized tumors of both histologic types.
The lower incidence of nonseminoma in the military and the increased incidence of localized tumors in both populations remain unexplained.
The U.S. Military and general populations may differ in the exposure to sunlight and other risk factors for melanoma, and therefore the incidence rates of melanoma may be different in these two populations. However, few studies have compared melanoma incidence rates and trends over time between the military and the general population.
Melanoma incidence rates from 1990 to 2004 among white active-duty military personnel and the general U.S. population were compared using data from the Department of Defense (DoD)’s Automated Central Tumor Registry (ACTUR) and the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program.
Age-adjusted melanoma rates overall were significantly lower in the military than in the general population; the incidence rate ratio (IRR) was 0.75 for men and 0.56 for women. Age-specific rates, however, were significantly lower among younger individuals aged <45 years but significantly higher among those aged 45 years or older (p-values<0.05). Melanoma incidence rose from 1990–1994 to 2000–2004 in both populations, with the most rapid increase (40%) among younger men in the military. Melanoma incidence rates also varied by branch of military service; rates were highest in the Air Force.
These results suggest that melanoma incidence rate patterns differ between the military and the general population.
Further studies of risk factors for melanoma in the military are needed to explain these findings.
Melanoma; incidence rates; Active duty; military; SEER program
Clear definitions of histological groups are essential for studies of liver and intrahepatic bile duct cancers. Thus, we developed a classification system based on abstracted information on histologies of liver and intrahepatic bile duct cancers diagnosed during 1978–2007 within all Surveillance, Epidemiology, and End Results (SEER) registries. Of 61,990 reported primary liver and intrahepatic bile duct cancers, 108 distinct ICD-O histology codes were identified. During the five recent years of diagnosis, 2003–2007, the leading histological groups were hepatocellular carcinoma (75%) and cholangiocarcinoma (12%). The remaining categories were other specified (3%) and poorly specified carcinomas (3%), hepatoblastomas (1%), sarcomas (1%), embryonal sarcomas (0.1%), other specified malignancies (0.05%), and poorly specified malignancies (5%). During 2003–2007, only 68% of diagnoses were microscopically confirmed. Factors contributing to incomplete histological classification may include reluctance to obtain diagnostic specimens from late stage cases and administration of therapy in lieu of histological confirmation after positive diagnostic imaging.
The proposed histological classification in this report may facilitate studies of primary liver cancers. This is of value because the inconsistent characterization of some cancers, particularly cholangiocarcinomas, may affect interpretation of incidence trends. Incomplete histological characterization of hepatocellular carcinomas was noted in this report. It is likely to be explained by guidelines affirming the use of non-invasive diagnostic and treatment procedures for this cancer.
Hepatocellular carcinoma; cholangiocarcinoma; microscopic confirmation; trends
The increases in thyroid cancer overall and in the predominant papillary type have been well documented, but trends for follicular thyroid cancer, a less common but more aggressive variant, have not been as well characterized. In this study, we determined the incidence patterns for follicular thyroid cancer and compared trends between the follicular and papillary thyroid cancers in the United States.
We used the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program to examine incidence in the United States during 1980–2009, stratified by demographic and tumor characteristics. Incidence rates (IR) were calculated, relative risks were expressed as incidence rate ratios (IRR), and temporal trends were expressed as percentage changes and plotted.
Overall we observed a modest increase in age-adjusted follicular thyroid cancer rates among women (31.89%) and men (35.88%). Rates increased most dramatically for regional stage tumors compared to localized tumors in women, whereas the rates for all tumor sizes rose. These findings reveal increases in more aggressive tumors in women in addition to small and localized tumors. The trends for males were different from those among females. Among males, the largest increase was observed for regional and smaller size tumors. The papillary-to-follicular IRR overall was 7.07 [95% confidence interval 6.91–7.24], which varied from 7.37 among Whites to 3.86 among Blacks (SEER race/ethnicity categories), and increased significantly from 3.98 during 1980–1984 to 9.88 during 2005–2009.
The different trends for follicular and papillary types of thyroid cancer illustrate that thyroid cancer is a heterogeneous disease. Our results do not support the hypothesis that increasing thyroid cancer rates are largely due to improvements in detection, and suggest the importance of evaluating thyroid cancer types separately in future studies.
The Armitage—Doll model with random frailty can fail to describe incidence rates of rare cancers influenced by an accelerated biological mechanism at some, possibly short, period of life. We propose a new model to account for this influence. Osteosarcoma and Ewing sarcoma are primary bone cancers with characteristic age-incidence patterns that peak in adolescence. We analyze SEER incidence data for whites younger than 40 years diagnosed during the period 1975−2005, with an Armitage—Doll model with compound Poisson frailty. A new model treating the adolescent growth spurt as the accelerated mechanism affecting cancer development is a significant improvement over that model. We also model the incidence rate conditioning on the event of having developed the cancers before the age of 40 years and compare the results with those predicted by the Armitage—Doll model. Our results support existing evidence of an underlying susceptibility for the two cancers among a very small proportion of the population. In addition, the modeling results suggest that susceptible individuals with a rapid growth spurt acquire the cancers sooner than they otherwise would have, if their growth had been slower. The new model is suitable for modeling incidence rates of rare diseases influenced by an accelerated biological mechanism.
Frailty; osteosarcoma; Ewing sarcoma; growth spurt; susceptibility; survival analysis
Thyroid cancer incidence has risen steadily over the last few decades in most of the developed world, but information on incidence trends in developing countries is limited. Sao Paulo, Brazil, has one of the highest rates of thyroid cancer worldwide, higher than in the United States. We examined thyroid cancer incidence patterns using data from the Sao Paulo Cancer Registry (SPCR) in Brazil and the National Cancer Institute's Surveillance Epidemiology End Results (SEER) program in the United States.
Data on thyroid cancer cases diagnosed during 1997–2008 were obtained from SPCR (n=15,892) and SEER (n=42,717). Age-adjusted and age-specific rates were calculated by sex and histology and temporal patterns were compared between the two populations.
Overall incidence rates increased over time in both populations and were higher in Sao Paulo than in the United States among females (SPCR/SEER incidence rate ratio [IRR]=1.65) and males (IRR=1.23). Papillary was the most common histology in both populations, followed by follicular and medullary carcinomas. Incidence rates by histology were consistently higher in Sao Paulo than in the United States, with the greatest differences for follicular (IRR=2.44) and medullary (IRR=3.29) carcinomas among females. The overall female/male IRR was higher in Sao Paulo (IRR=4.17) than in SEER (IRR=3.10) and did not change over time. Papillary rates rose over time more rapidly in Sao Paulo (annual percentage change=10.3% among females and 9.6% among males) than in the United States (6.9% and 5.7%, respectively). Regardless of sex, rates rose faster among younger people (<50 years) in Sao Paulo, but among older people (≥50 years) in the United States. The papillary to follicular carcinoma ratio rose from <3 to >8 among both Sao Paulo males and females, in contrast to increases from 9 to 12 and from 6 to 7 among U.S.males and females, respectively.
Increased diagnostic activity may be contributing to the notable rise in incidence, mainly for papillary type, in both populations, but it is not likely to be the only reason. Differences in iodine nutrition status between Sao Paulo and the U.S. SEER population might have affected the observed incidence patterns.
Black renal cell carcinoma (RCC) patients tend to have poorer prognosis than white patients. We examined whether the racial disparity in RCC patient survival varies by demographic and clinical characteristics.
Nearly 40,000 patients (4,359 black and 34,991 white) diagnosed with invasive RCC from 1992 to 2007 were identified from 12 registries in NCI’s Surveillance, Epidemiology, and End Results program, covering about 14% of the U.S. population. Relative survival rates through 2008 were computed using the actuarial method.
Proportionally more blacks than whites were diagnosed with RCC under age 50 and with localized cancer. Overall, the 5-year relative survival rates were 72.6% (95% confidence interval 72.0% – 73.2%) for white and 68.0% (66.2% – 69.8%) for black patients. Survival was higher among women than men and among younger than older patients. Survival decreased with advancing tumor stage and, within each stage, decreased with increasing tumor size. Patients with clear cell RCC, a more common form among whites, had poorer prognosis than patients with papillary or chromophobe subtypes, which are more common among blacks. Survival for patients who received no surgical treatment (10.5% of white patients and 14.5% of black patients) was substantially lower than for patients treated with nephrectomy, with similar survival among whites and blacks. In all other demographic and clinical subgroups of patients, whites consistently had a survival advantage over blacks.
White RCC patients consistently have a survival advantage over black patients, regardless of age, sex, tumor stage or size, histological subtype, or surgical treatment.
Renal cell carcinoma; survival; race; stage at diagnosis; histological type
The interpretation of uterine cancer rates is hindered by the inclusion of women whose uterus has been surgically removed in the population at risk. Hysterectomy prevalence varies widely by state and race/ethnicity, exacerbating this issue.
We estimated hysterectomy-corrected, age-adjusted uterine corpus cancer incidence rates by race/ethnicity for 49 states and the District of Columbia during 2004-2008 using case counts obtained from population-based cancer registries; population data from the U.S. Census Bureau; and hysterectomy prevalence data from the Behavioral Risk Factor Surveillance System. Corrected and uncorrected incidence rates were compared with regard to geographic and racial/ethnic disparity patterns and the association with obesity.
Among non-Hispanic whites, uterine cancer incidence rates (per 100,000 woman-years) uncorrected for hysterectomy prevalence ranged from 17.1 in Louisiana to 32.1 in New Jersey, mirrored regional hysterectomy patterns, and were not correlated with obesity prevalence (Pearson’s correlation coefficient, r = 0.06, two-sided p = 0.68). In comparison, hysterectomy-corrected rates were higher by 30% (District of Columbia) to more than 100% (Mississippi, Louisiana, Alabama, and Oklahoma), displayed no discernible geographic pattern, and were moderately associated with obesity (r = 0.37, two-sided p = 0.009). For most states, hysterectomy correction diminished or reversed the black/white deficit and accentuated the Hispanic/white deficit.
Failure to adjust uterine cancer incidence rates for hysterectomy prevalence distorts true geographic and racial patterns and substantially underestimates the disease burden, particularly for Southern states.
Correction for hysterectomy is necessary for the accurate evaluation of uterine cancer rates.
endometrium; uterus; hysterectomy; geographic pattern; disparity
Burkitt lymphoma (BL) in the general population and immunosuppressed persons with AIDS in United States was characterized by three age-specific incidence peaks near 10, 40 and 70 years. We hypothesized that BL from different geographical areas may exhibit pediatric, adult, and elderly age incidence peaks. We investigated this hypothesis using data on 3403 cases obtained from the International Agency for Research on Cancer (1978–2002). Data from Africa were sparse or incomplete, and thus were excluded. Age-standardized rates (ASR) and age-specific incidence rates were calculated, supplemented with calculations performed using age-period-cohort models. The ASR rose 5.3% (95% confidence interval (CI), 5.0–5.6) per year in males and 4.6% (95% CI, 4.5–4.8) in females. The ASR increased gradually in children and steeply in adults and most rapidly in the elderly both in males and females. Overall, BL male/female ASR ratio was 2.5, but it declined from 3.1 (95% CI, 3.0–3.3) for pediatric BL to 2.3 (95% CI 2.2–2.4) for adult BL and 1.5 (95% CI, 1.4–1.6) for elderly BL. Age-specific incidence peaks occurred near 10 years and 70 years in all regions and periods. A peak near 40 years of age emerged in the mid-1990s, particularly in men. Findings using APC models confirmed those based on standard analyses. Our findings, based on international BL cases, support our hypothesis that BL is multimodal and that BL peaks at different ages may be clues to differences in the etiology and/or biology of BL at those ages.
Burkitt lymphoma; epidemiology; multimodal cancer; non-Hodgkin lymphoma; HIV/AIDS
Prostate cancer (CaP) is the leading cancer among men of African descent in the USA, Caribbean, and Sub-Saharan Africa (SSA). The estimated number of CaP deaths in SSA during 2008 was more than five times that among African Americans and is expected to double in Africa by 2030. We summarize publicly available CaP data and collected data from the men of African descent and Carcinoma of the Prostate (MADCaP) Consortium and the African Caribbean Cancer Consortium (AC3) to evaluate CaP incidence and mortality in men of African descent worldwide. CaP incidence and mortality are highest in men of African descent in the USA and the Caribbean. Tumor stage and grade were highest in SSA. We report a higher proportion of T1 stage prostate tumors in countries with greater percent gross domestic product spent on health care and physicians per 100,000 persons. We also observed that regions with a higher proportion of advanced tumors reported lower mortality rates. This finding suggests that CaP is underdiagnosed and/or underreported in SSA men. Nonetheless, CaP incidence and mortality represent a significant public health problem in men of African descent around the world.
Tumor stage at diagnosis often varies by racial/ethnic group, possibly due to inequitable healthcare access. Within the Department of Defense (DoD) Military Health System, beneficiaries have equal healthcare access. This study aimed to determine if tumor stage differed between whites and blacks for breast, cervical, colorectal and prostate cancers, which have effective screening regimens, based on data from the DoD’s Automated Cancer Tumor Registry from 1990–2003.
Distributions of tumor stage (localized vs. non-localized) between whites and blacks in the military were compared stratified by sex, active duty status, and age at diagnosis. Logistic regression was used to further adjust for age, marital status, year of diagnosis, geographic region, military service branch and tumor grade. Distributions of tumor stage were then compared between the military and general populations.
Racial differences in the distribution of stage were significant only among non-active duty beneficiaries. After adjusting for covariates, earlier stages of breast cancer after age 49 and prostate cancer after age 64 were significantly more common among white than black non-active duty beneficiaries (p<0.05), although the absolute difference for prostate cancer was minimal. Racial differences in stage for cervical and colorectal cancers were not significant after adjustment. Compared to the general population, the racial differences in the military were similar or slightly attenuated.
Racial disparities in stage at diagnosis were apparent in the DoD’s equal access healthcare system among older non-active duty beneficiaries. Socioeconomic status, supplemental insurance, cultural beliefs and biological factors may be related to these results.
Increases in thyroid papillary carcinoma incidence rates have largely been attributed to heightened medical surveillance and improved diagnostics. We examined papillary carcinoma incidence in an equal-access healthcare system by demographics, which are related to incidence.
Incidence rates during 1990-2004 among white and black individuals aged 20-49 years in the military and the general U.S. population were compared using data from the Department of Defense’s Automated Central Tumor Registry and the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER-9) program.
Incidence was significantly higher in the military than in the general population among white women [incidence rate ratio (IRR)=1.42, 95% 95% confidence interval (CI)=1.25-1.61], black women (IRR=2.31, 95% CI=1.70-2.99), and black men (IRR=1.69, 95% CI=1.10-2.50). Among whites, differences between the two populations were confined to rates of localized tumors (women: IRR=1.73, 95% CI=1.47-2.00; men: IRR=1.51, 95% CI=1.30-1.75), which may partially be due to variation in staging classification. Among white women, rates were significantly higher in the military regardless of tumor size, and rates rose significantly over time both for tumors ≤2 cm (military: IRR=1.64, 95% CI=1.18-2.28; general population: IRR=1.55, 95% CI=1.45-1.66) and >2 cm (military: IRR=1.74, 95% CI=1.07-2.81; general population: IRR=1.48, 95% CI=1.27-1.72). Among white men, rates increased significantly only in the general population. Incidence also varied by military service branch.
Heightened medical surveillance does not appear to fully explain the differences between the two populations or the temporal increases in either population.
These findings suggest the importance of future research into thyroid cancer etiology.
Thyroid Neoplasms; Incidence; SEER Program; Military Personnel; United States/epidemiology
A prospective study of diet and cancer has not been conducted in India; consequently, little is known regarding follow-up rates or the completeness and accuracy of cancer case ascertainment.
We assessed follow-up in the India Health Study (IHS; 4,671 participants aged 35–69 residing in New Delhi, Mumbai, or Trivandrum). We evaluated the impact of medical care access and relocation, re-contacted the IHS participants to estimate follow-up rates, and conducted separate studies of cancer cases to evaluate registry coverage (604 cases in Trivandrum) and the accuracy of self- and proxy-reporting (1600 cases in New Delhi and Trivandrum).
Over 97% of people reported seeing a doctor and 85% had lived in their current residence for over six years. The 2-year follow-up rate was 91% for Trivandrum and 53% for New Delhi. No cancer cases were missed among public institutions participating in the surveillance program in Trivandrum during 2003–04; but there are likely to be unmatched cases (ranging from 5 to13% of total cases) from private hospitals in the Trivandrum registry, as there are no mandatory reporting requirements. Vital status was obtained for 36% of cancer cases in New Delhi as compared to 78% in Trivandrum after a period of 4 years.
A prospective cohort study of cancer may be feasible in some centers in India with active follow-up to supplement registry data. Inclusion of cancers diagnosed at private institutions, unique identifiers for individuals, and computerized medical information would likely improve cancer registries.
Cancer; end-point; follow-up; registry; prospective cohort; India
Previous research has noted higher cancer mortality rates and lower survival among males than females. However, systematic comparisons of these two metrics by sex has been limited.
We extracted U.S. vital rates and survival data from the Surveillance, Epidemiology and End Results Database for 36 cancers by sex and age for the period 1977–2006. We compared sex-specific mortality rates and male-to-female mortality rate ratios (MRRs). We also extracted case data which included age and date of diagnosis, sex, primary cancer site, tumor stage and grade, survival time, vital status, and cause of death. Relative cancer-specific hazard ratios (HRs) for death in the 5-year period following diagnosis were estimated with Cox proportional hazards models, adjusted for covariates.
For the vast majority of cancers, age-adjusted mortality rates were higher among males than females with the highest male-to-female MRR for lip (5.51), larynx (5.37), hypopharynx (4.47), esophagus (4.08) and urinary bladder (3.36). Cancer-specific survival was, for most cancers, worse for males than females, but such disparities were drastically less than corresponding MRRs; e.g., lip (HR = 0.93), larynx (1.09), hypopharynx (0.98), esophagus (1.05), and urinary bladder (0.83).
Male-to-female MRRs differed markedly while cancer survival disparities were much less pronounced. This suggests that sex-related cancer disparities are more strongly related to etiology than prognosis.
Future analytical studies should attempt to understand causes of observed sex disparities in cancer.
Sex; Male; Female; SEER program; Neoplasms; Mortality; Epidemiology
Objective. To evaluate oral cavity and pharynx cancer (OCPC) patterns by gender. Methods. We used Surveillance, Epidemiology, and End Results program data for 71,446 cases diagnosed during 1975–2008 to classify OCPC by anatomic subsite as potentially HPV-related or not, with oral tongue cancer considered a separate category. Results. Total OCPC rates among men were 2–4 times those among women. Among whites, total OCPC rates rose in the younger age groups due to substantial increases in successive birth cohorts for HPV-related cancers, more rapid among men than women, and oral tongue cancers, more rapid among women than men. Among blacks, total OCPC rates declined among cohorts born since 1930 reflecting the strong downward trends for HPV-unrelated sites. Among Hispanics and Asians, HPV-unrelated cancer rates generally declined, and oral tongue cancer rates appeared to be converging among young men and women. Conclusions. Decreases in total OCPC incidence reflect reductions in smoking and alcohol drinking. Rising HPV-related cancers among white men may reflect changing sexual practices. Reasons for the increasing young oral tongue cancer rates are unknown, but the narrowing of the gender differences provides a clue.
The increasing incidence of thyroid cancer in the United States is well documented. In this study, we assessed the incidence patterns by histologic type according to demographic and tumor characteristics to further our understanding of these cancers.
We used the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program for cases diagnosed during 1992–2006 to investigate patterns for the four major histologic types of thyroid cancer by gender, race/ethnicity, and age as well as registry, tumor stage, and size.
Among women, papillary thyroid cancer rates were highest among Asians (10.96 per 100,000 woman-years) and lowest among blacks (4.90 per 100,000 woman-years); follicular cancer rates did not vary substantially by race/ethnicity (p-values >0.05), medullary cancer rates were highest among Hispanics (0.21 per 100,000 woman-years) and whites (0.22 per 100,000 woman-years), and anaplastic rates were highest among Hispanics (0.17 per 100,000 woman-years). Among men, both papillary and follicular thyroid cancer rates were highest among whites (3.58 and 0.58 per 100,000 man-years, respectively), medullary cancer rates were highest among Hispanics (0.18 per 100,000 man-years), and anaplastic rates were highest among Asians (0.11 per 100,000 man-years). Racial/ethnic-specific rates did not vary notably across registries. In contrast to age-specific rates of papillary thyroid cancer that peaked in midlife (age 50), especially pronounced among women, rates for follicular, medullary, and anaplastic types continued to rise across virtually the entire age range, especially for anaplastic carcinomas. Female-to-male incidence rate ratios among whites decreased with age most steeply for the follicular type and least steeply for the medullary type; it was <1 until the very oldest ages for the anaplastic type.
We conclude that the similar age-specific patterns and lack of geographical variation across the SEER racial/ethnic groups indicate that detection effects cannot completely explain the observed thyroid cancer incidence patterns as variation in the amount or quality of healthcare provided has been shown to vary by SEER racial/ethnic groups, gender, and age. We find that the variations in age-specific patterns by gender and across histologic types are intriguing and recommend that future etiologic investigation focus on exogenous and endogenous exposures that are experienced similarly by racial/ethnic groups, more strongly among women, and distinctively by age.