shows sex-specific, age-adjusted incidence rates and male-to-female IRRs stratified by time period for each cancer. During 1975-2004, the ten most common cancers diagnosed among US males were lung and bronchus (93.2 per 100,000 man-years), colon and rectum (70.3), urinary bladder (37.5), non-Hodgkin lymphoma (21.4), skin excluding basal and squamous (19.7), kidney and renal pelvis (14.8), stomach (14.1), pancreas (13.6), lymphocytic leukemia (8.6) and larynx (8.5). For US females, the ten most frequent cancers were breast (126.4 per 100,000 woman-years), colon and rectum (51.2), lung and bronchus (45.2), non-Hodgkin lymphoma (14.4), skin excluding basal and squamous (13.8), pancreas (10.2), urinary bladder (9.6), thyroid (8.9), kidney and renal pelvis (7.2) and stomach (6.4). The ten cancers with the largest male-to-female IRR during 1975-2004 were Kaposi sarcoma (IRR=28.73), lip (7.16), larynx (5.17), mesothelioma (4.88), hypopharynx (4.13), urinary bladder (3.92), esophagus (3.49), tonsil (3.07), oropharynx (3.06) and other urinary organs (2.92). During 1975-2004, only five cancers investigated had a higher incidence in females compared with males: breast (IRR=0.01), peritoneum, omentum and mesentery (0.18), thyroid (0.39), gallbladder (0.57), and anus, anal canal and anorectum (0.81).
Incidence Rates and Male-to-Female Incidence Rate Ratios by Cancer, 1975-2004
shows the relative change in male-to-female IRRs and relative change in sex-specific incidence rates for the periods 1985-1994 and 1995-2004 compared with 1975-1984 for cancers showing a consistently increasing or decreasing IRR and incidence rates for each sex of at least 0.2 per 100,000 listed according to percent change in IRR. During 1975-2004, tonsil cancer had the largest increase in male-to-female IRR, and this was the result of an increasing male incidence and decreasing female incidence. Other cancers with rising IRRs were esophagus and mesothelioma, the former due to increases among males not apparent among females, and the latter a female decrease in incidence. Rates for the remaining cancers with rising male-to-female IRRs increased among both sexes, but more so among males than females.
Male-to-Female Incidence Rate Ratios and Percent Changes for Selected Cancers, 1975-2004
Many cancers had a decline in the male-to-female IRR during 1975-2004. The IRRs for the cancer sites ureter, floor of mouth, retroperitoneum, and lip decreased due to faster declines in male incidence than in female incidence. Reductions in IRR for other cancers - pancreas, nose, nasal cavity and middle ear, gum and other mouth, Hodgkin lymphoma, and larynx - were solely caused by decreased male incidence, with female rates remaining fairly stable. More rapidly rising rates among females than males reduced the IRRs for cancers of the kidney and renal pelvis, cranial nerves and other nervous system, and thyroid. Perhaps the most notable declining IRR was that for lung and bronchus cancer, which is singular in that it was caused by a simultaneous decrease in male rates and increase in female rates.
Of the cancer sites in , those with the largest increases in male incidence between the periods 1975-1984 and 1995-2004 were skin excluding basal and squamous (111%), liver and intrahepatic bile duct (103%), anus, anal canal and anorectum (58%), and thyroid (44%). For females, the cancer sites were liver and intrahepatic bile duct (88%), thyroid (76%), skin excluding basal and squamous (69%), and lung and bronchus (59%). Over the same time period, the sites with the largest decreases in incidence have been lip (57%), floor of mouth (48%), larynx (30%), and gum and other mouth (30%) for males, and floor of mouth (41%), tonsil (29%), ureter (15%), and gum and other mouth (14%) for females.
shows sex-specific incidence rates and male-to-female IRRs for specific histologic groups of selected cancers. The rates and IRRs for nearly all histologic groups follow the same trends as their parent cancer site. However, this is not true for the two histologic types of esophageal cancer, which trended in opposite directions. The IRR, by 10-year period, for all esophageal cancers combined increased from 3.14, to 3.43 to 3.82 (), however, this is a combination of increasing IRRs for esophageal adenocarcinoma (6.25, 7.96, and 7.69) and decreasing IRRs for esophageal squamous cell carcinoma (2.93, 2.57, and 2.25) (). Although the IRRs did not change greatly over time, the IRRs for hepatocellular carcinoma ranged 3.44-3.56, considerably larger than those for intrahepatic bile duct carcinoma which ranged 1.51-1.62, not apparent in the overall IRR for liver and intrahepatic bile duct cancer range of 2.51-2.71. In contrast to the overall lung and bronchus cancer IRR of 2.06, that declined from 3.00 to 1.61 over the decades, the overall IRR ranged from 3.50 for squamous cell carcinoma, to 2.19 for large cell, 1.60 for small cell, and 1.53 for adenocarcinoma; IRRs for each type declined from an early maximum of 5.29 for squamous cell to 1.26 for small cell carcinoma recently.
Incidence Rates and Male-to-Female Incidence Rate Ratios by Cancer Site and Histology, 1975-2004
Incidence rates and male-to-female IRRs are plotted by age of diagnosis for nine cancer sites/histologies () selected because they had the most extreme consistent changes in male-to-female IRR and an incidence of at least 0.4 per 100,000 which was increasing in at least one of the sexes (graphs for other cancers, Supplementary Figures 1-30
, can be accessed online5
). During the earliest decade the male-to-female IRR for tonsil cancer was about 2 at ages less than 70 years and rose to about 4 at older ages; by the recent decade, rising male rates and declining female rates resulted in a male-to-female IRR of more than 5 at ages 40-59 years (). Rates for the cancer site skin excluding basal and squamous () predominated among females at younger ages (<40 years) and among males in the older age groups (≥40), and rates rose over time more rapidly among younger women and among older men, resulting in declines in the male-to-female IRR at younger ages and increases at older ages. The incidence of esophageal squamous cell carcinoma among males at all ages and in females less than 70 years of age declined, and the male-to-female IRR decreased at older ages from about 3 to 2 (). The male-to-female IRR for esophageal adenocarcinoma exceeded 10 at ages 50-59 years and declined with age to 4-5 at the oldest ages (). Rates for anus, anal canal and anorectal cancers increased comparably in both sexes in nearly all age groups, making the male-to-female IRR fairly stable and less than 1 at ages of more than 50 years (). The increasing rates of hepatocellular carcinoma in younger age groups (<50 years) has been more rapid among males than females, and the male-to-female IRR rose from less than 3 to more than 5, in contrast to decreases in the male-to-female IRR at older ages (). Kidney and renal pelvis cancer IRR were about one at very young ages (Wilms tumors), decreased over the decades at ages 10-39, and rose to a fairly constant two at older ages in spite of rising rates (). Thyroid cancer male-to-female IRR were around 0.2 at ages 20-29 and rose to at least 0.7 at the oldest ages; rates rose over time more rapidly among younger women and older men, leading to progressively lower IRRs (). Male rates for lung and bronchus malignancies declined slightly at virtually all ages while female rates increased, especially in the age groups of 60 years and older (), and the male-to-female IRR declined dramatically across all adult age groups, dropping below 1 in recent years among those less than 40 years of age.
Male-To-Female Incidence Rate Ratios and Sex-Specific Incidence Rates by Age, 1975-2004:
Rates during the period 1975-2004 for all cancers combined and for all cancers excluding the sex-specific sites were higher among females than males at adult ages less than 50 years and clearly higher among males than females at ages 60+ years (). When rates for total cancer excluding the sex-specific sites and breast cancer are considered, the male-to-female IRR exceeds one at all ages 30+. Across all ages combined, the cancer burden was higher in males than females for total cancer (male-to-female IRR=1.37, 95%CI: 1.37-1.38), total cancer excluding sex-specific sites (1.14, 95%CI: 1.14-1.14), and total cancer excluding sex-specific sites and breast cancer (1.77, 95%CI: 1.76-1.77).
Male-to-female incidence rate ratios and sex-specific incidence rates by age for total cancer, total cancer excluding sex-specific sites, and total cancer excluding sex-specific sites and breast, 1975-2004