To assess the impact of laparoscopy on utilization of partial nephrectomy (PN) by comparing national utilization trends in patients undergoing surgery for localized renal tumors.
Using linked Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we retrospectively examined trends in procedure utilization from 1995–2007 for patients undergoing surgery for localized (stage I/II) renal masses. Procedures were classified as open radical nephrectomy (ORN), laparoscopic radical nephrectomy (LRN), open partial nephrectomy (OPN), and laparoscopic partial nephrectomy (LPN). Patients were further stratified by tumor size (≤4cm, >4 to ≤7cm, >7cm). Data were primarily analyzed using logistic regressions.
11,689 patients (mean age 74.4±5.7 years, 56% male) with a mean tumor size of 4.7±3.3cm met inclusion criteria. From 1995–2007, ORN rates decreased while for each year successive year, patients were more likely to be treated with OPN (OR 1.17, CI 1.14–1.19), LRN (OR 1.44, CI 1.41–1.47) and LPN (OR 1.75, CI 1.68–1.83). While the increased utilization of OPN (7.5% vs. 13.6%, p<0.001) and LPN (0% vs. 14.2%, p<0.001) reached statistical significance, this was offset by a marked increase in LRN over the same time period (3.0% vs. 43.0%, p<0.001).
Despite increasing emphasis on nephron preservation, PN utilization rates remain low. Compared to a 40% increase in LRN, utilization of PN increased by only 20% from 1995–2007. As a result, 72% of identified Medicare beneficiaries with localized tumors were managed with RN in 2007. The trade-off of minimally invasive surgery for nephron preservation may have adverse long term consequences.
kidney; carcinoma; nephrectomy; nephron sparing; partial nephrectomy; laparoscopy
BRCA1/2 testing is not recommended for children, as risk reduction measures and screening are not generally recommended before 25 years old (YO). Little is known about the prevalence and predictors of parent communication to offspring and how offspring respond to this communication.
Semi-structured interviews were conducted with parents who had BRCA1/2 testing and at least one child <25 YO. Logistic regressions were utilized to evaluate associations with communication. Framework analysis was utilized to analyze open-ended responses.
253 parents completed interviews (61% response rate), reporting on 505 offspring. 29% of parents were BRCA1/2 mutation carriers. 334 (66%) offspring learned of their parent’s test result. Older offspring age (p<=0.01), offspring gender (female, p=0.05), parents’ negative test result (p=0.03) and parents’ education (high-school only, p=0.02) were associated with communication to offspring. The most frequently reported initial offspring responses were neutral (41%) or relief (28%). 13% of offspring were reported to experience concern or distress (11%) in response to parental communication of their test results. Distress was more frequently perceived among offspring learning of their parent’s BRCA1/2 positive or variant of uncertain significance result.
Many parents communicate their BRCA1/2 test results to young offspring. Parents’ perceptions of offspring responses appear to vary by offspring age and parent test result. A better understanding of how young offspring respond to information about hereditary risk for adult cancer could provide opportunities to optimize adaptive psychosocial responses to risk information and performance of health behaviors, in adolescence and throughout an at-risk lifespan.
This study examines whether and how report of a change in walking behavior, incident preclinical mobility disability (PCMD), predicts subsequent reduction in walking activity.
Materials and Methods
Data are from a prospective study of 436 community-dwelling women age 70–79 years. Outcome measures include subjective and objective measures of walking ability at 3 years.
Incident PCMD is associated with loss of walking abilities at 3-years, regardless of baseline physical impairment. Compared to women without, women with incident PCMD at 1.5 years after baseline were 2.7 (95% CI 1.4–7.2) times more likely to report that they no longer walk outdoors at least 8 blocks and 4.9 (1.9–13.1) times more likely to report new difficulty walking. Incident PCMD was also associated with declines in objective outcomes. Incident PCMD is an independent marker of subsequent decreased walking activity.
Incident PCMD appears to be a target for programs to prevent declines in walking activity in older adults.
disability; geriatrics; epidemiology; prevention; physical activity
Although functional status serves as a major predictor of morbidity, researchers and clinicians use different terms and measures, limiting comparisons across studies. To demonstrate how differing measures may generate varied findings, we compared and contrasted data from the SF-12 Health Survey Physical Component Summary Scale (SF-12 PCS) and the Enforced Social Dependency Scale (ESDS). The sample consisted of 49 women ages 65 and over recovering from gynecological cancer surgery with data collection at baseline (postoperative period) then 3 and 6 months. Analysis of the relationship between SF-12 PCS and ESDS over time using Generalized Estimating Equations (GEE) demonstrated the relationship was less than 1.0, signaling less than perfect agreement between measures (Beta=0.16, p=0.002). These findings suggest that that the two measures are not interchangeable and may produce conflicting evidence. This highlights the importance of researchers' and clinicians' careful conceptualization and operationalization of functional status prior to measure selection.
Hospital rankings have become integral to the marketing strategies of many health care systems. Methodology used in compiling these lists appears highly flawed.
Improve on current hospital ranking systems and to develop a more meaningful measure of a urology department’s contribution to the field, we developed an academic ranking score (ARS) based on publicly available data.
Design, setting, and participants
An active faculty list was assembled for each department. A list of all publications from each department from 2005 to 2010 was then compiled. Only publications with faculty members as first or last author were considered. The ARS was then derived by identifying the number of publications within an institution, normalized by the impact factor of the peer-reviewed journal in which the publication appeared.
The 2010 U.S. News and World Report (USNWR) urology list was reranked based on ARS and compared with the USNWR rank list. ARS was also calculated for several leading European urologic centers.
Results and limitations
A total of 6437 urologic publications were indexed to calculate the ARS. Two of the top three programs in the USNWR rankings dropped out of the top 10. The top 10 academically ranked programs increased or decreased an average of >5 positions (range: 0–17). No correlation was seen between programs ranked in the top 10 by USNWR and our objective ARS method (Spearman ρ: −0.1; p = 0.75). Because ARS only includes first- or last-author publications for faculty with clinical duties, ARS likely excludes basic science contributions and contributions from nonclinical faculty.
Ranking of urology departments through quantification of each program’s recent academic contribution, as captured by the ARS, differs substantially from rankings developed by USNWR. Integration of such objective measures into an overall urology program ranking system would replace current subjective opinions marred by historical biases with up-to-date merit-based assessments.
Little is known about the role of folate and polymorphisms associated with folate metabolism on prostate cancer risk in populations of African origin. We examined the relationship between serum folate and prostate cancer and whether any association was modified by genetic polymorphisms for folate metabolism. The study was case–control in design and consisted of 218 men 40–80 years old with newly diagnosed, histologically confirmed prostate cancer and 236 cancer-free men attending the same urology clinics in Jamaica, March 2005–July 2007. Serum folate was measured by an immunoassay method and genomic DNA evaluated for MTHR (C677T and A1298C), MTRR A66G, and MTR A2756G polymorphisms. Mean serum folate concentration was higher among cases (12.3 ± 4.1 nmol/L) than controls (9.7 ± 4.2 nmol/L). Serum folate concentration showed a positive association with prostate cancer (OR, 4.41; CI, 2.52–7.72 per 10 nmol/L) regardless of grade. No interactions were observed between genotype and folate concentration, but a weak gene effect was observed for MTHFR A1298C and low-grade prostate cancer. Larger studies to investigate the role of gene–gene/gene–diet interactions in Black men are needed.
Prostate cancer; Serum folate; Folate pathway genes; African ancestry
Response fatigue can cause measurement error and misclassification problems in survey research. Questions asked later in a long survey are often prone to more measurement error or misclassification. The response given is a function of both the true response and participant response fatigue. We investigate the identifiability of survey order effects and their impact on estimators of treatment effects. The focus is on fatigue that affects a given answer to a question rather than fatigue that causes non-response and missing data. We consider linear, Gamma, and logistic models of response that incorporate both the true underlying response and the effect of question order. For continuous data, survey order effects have no impact on study power under a Gamma model. However, under a linear model that allows for convergence of responses to a common mean, the impact of fatigue on power will depend on how fatigue affects both the rate of mean convergence and the variance of responses. For binary data and for less than a 50% chance of a positive response, order effects cause study power to increase under a linear probability (risk difference) model, but decrease under a logistic model. The results suggest that measures designed to reduce survey order effects might have unintended consequences. We present a data example that demonstrates the problem of survey order effects.
Robotic surgery has been widely adopted for radical prostatectomy. We hypothesize that this change is rapidly shifting procedures away from hospitals that do not offer robotics and consequently increasing patient travel.
A population-based observational study of all prostatectomies for cancer in NY, NJ, and PA from 2000–2009 was performed using hospital discharge data. Hospital procedure volume was defined as the number of prostatectomies performed for cancer in a given year. Straight-line travel distance to treating hospital was calculated for each case. Hospitals were contacted to determine year of acquisition of first robot.
From 2000–2009, the total number of prostatectomies performed annually increased substantially. The increase occurred almost entirely at the very high volume centers (≥106 prostatectomies/year). The number of hospitals performing prostatectomy fell 37% from 2000–2009. By 2009, the 9% (21/244) of hospitals that had very high volume performed 57% of all prostatectomies, and the 35% (86/244) of hospitals with a robot performed 85% of all prostatectomies. Median travel increased 54% from 2000–2009, p<0.001. The proportion of patients traveling ≥15 miles increased from 24% to 40%, p<0.001.
Over the past decade, the number of radical prostatectomies performed has risen substantially. These procedures have been increasingly centralized at high volume centers, leading to longer patient travel distances. Few prostatectomies are now performed at hospitals that do not offer robotic surgery. Future work should focus on the impact of these trends on cancer control, functional outcomes, access to care and cost.
The treatment of localized renal cell carcinoma remains overly subjective. The R.E.N.A.L.- Nephrometry Score (NS) quantifies the salient characteristics of renal mass anatomy in an objective and reproducible manner. We evaluated treatment patterns of solid renal masses based on quantifiable anatomic features using Nephrometry.
Nephrometry scores were available in 615 patients in our prospective kidney tumor database (2000-2010). The NS sum and its individual component scores were analyzed to determine their relationship to treatment approach.
Median age, age-adjusted Charlson Co-Morbidity Index (CCI), and estimated GFR were 60 years (25-89), 2 (0-10), and 80.5 ml/min (5.1-120.0), respectively. Increasing tumor complexity as measured by a higher overall Nephrometry Score was associated with both radical nephrectomy (RN) and open partial nephrectomy (PN) (p<0.0001). Compared to patients who underwent PN, patients treated with RN had significantly higher size (R), central proximity (N), and location (L) component scores (p<0.001). Furthermore, tumors treated with a RN were more often hilar (p<0.001). Similarly, compared to minimally-invasive PN (laparoscopic or robotic), open PN was associated with an increasing individual component score for size, endophycity and central proximity to the collecting system (p<0.001) and non-polar location (p=0.016).
The R.E.N.A.L. – Nephrometry score standardizes reporting of solid renal masses and appears to effectively stratify by treatment type. Although only one part of the treatment decision-making process, Nephrometry aids in objectifying previously subjective measures.
kidney cancer; Nephrometry; small renal mass (SRM)
Prognosis in renal cell carcinoma (RCC) is dependent on tumor stage at presentation, with significant differences in survival between early and late stage disease. Currently, there are no screening tests or biomarkers identified for the early detection of kidney cancer. Here, we investigate if serum amino acid profiles are a potentially useful biomarker in patients with RCC.
Materials and Methods
The concentrations of 26 different amino acids were determined in serum taken pre-operatively from 189 RCC patients and 104 age and sex matched controls.
Statistically significant changes were observed in patient levels of 15 different amino acids, with 13 being decreased and two being elevated. A logistic regression model utilizing eight amino acids including cysteine, ornithine, histidine, leucine, tyrosine, proline, valine and lysine was created to distinguish cases from controls. A receiver operator curve based on this model had an area under the curve of 0.81. This same model also had predictive value in predicting overall survival and tumor recurrence in RCC patients.
Our findings suggest that serum amino acid levels may be useful as a screening tool for the identification of individuals with RCC and predicting patient outcomes.
Kidney Cancer; biomarker; serum; amino acids
The impact of post-treatment neck dissection on prolonged feeding tube dependence in head and neck squamous cell cancer (HNSCC) patients treated with primary radiation or chemoradiation remains unknown.
Retrospective cohort study using propensity score adjustment to investigate the effect of neck dissection on prolonged feeding tube dependence.
A review of 67 patients with node positive HNSCC (T1-4N1-3), treated with primary radiation or chemoradiation, with no evidence of tumor recurrence and follow-up of at least 24 months was performed. Following adjustment for covariates, the relative risk of feeding tube dependence at 18 months was significantly increased in patients treated with post-treatment neck dissection (RR 4.74, 95% CI 2.07-10.89). At 24 months, the relative risk of feeding tube dependence in the patients having undergone neck dissection increased further (RR 7.66, 95% CI 2.07-10.89). Of patients with feeding tubes two years after completing treatment, 75% remained feeding tube dependent.
Neck dissection may contribute to chronic oropharyngeal dysphagia in HNSCC patients treated with primary radiation or chemoradiation.
Counseling patients with enhancing renal mass currently occurs in the context of significant uncertainty regarding tumor pathology.
We evaluated whether radiographic features of renal masses could predict tumor pathology and developed a comprehensive nomogram to quantitate the likelihood of malignancy and high-grade pathology based on these features.
Design, setting, and participants
We retrospectively queried Fox Chase Cancer Center’s prospectively maintained database for consecutive renal masses where a Nephrometry score was available.
All patients in the cohort underwent either partial or radical nephrectomy.
The individual components of Nephrometry were compared with histology and grade of resected tumors. We used multiple logistic regression to develop nomograms predicting the malignancy of tumors and likelihood of high-grade disease among malignant tumors.
Results and limitations
Nephrometry score was available for 525 of 1750 renal masses. Nephrometry score correlated with both tumor grade (p < 0.0001) and histology (p < 0.0001), such that small endophytic nonhilar tumors were more likely to represent benign pathology. Conversely, large interpolar and hilar tumors more often represented high-grade cancers. The resulting nomogram from these data offers a useful tool for the preoperative prediction of tumor histology (area under the curve [AUC]: 0.76) and grade (AUC: 0.73). The model was subjected to out-of-sample cross-validation; however, lack of external validation is a limitation of the study.
The current study is the first to objectify the relationship between tumor anatomy and pathology. Using the Nephrometry score, we developed a tool to quantitate the preoperative likelihood of malignant and high-grade pathology of an enhancing renal mass.
Kidney; Carcinoma; Renal cell; Nomograms; Nephrometry; Anatomy
Breast density is one of the strongest risk factors for breast cancer, but determinants of breast density in young women remain largely unknown.
Associations of height, adiposity and body fat distribution with percentage dense breast volume (%DBV) and absolute dense breast volume (ADBV) were evaluated in a cross-sectional study of 174 healthy women, 25 to 29 years old. Adiposity and body fat distribution were measured by anthropometry and dual-energy X-ray absorptiometry (DXA), while %DBV and ADBV were measured by magnetic resonance imaging. Associations were evaluated using linear mixed-effects models. All tests of statistical significance are two-sided.
Height was significantly positively associated with %DBV but not ADBV; for each standard deviation (SD) increase in height, %DBV increased by 18.7% in adjusted models. In contrast, all measures of adiposity and body fat distribution were significantly inversely associated with %DBV; a SD increase in body mass index (BMI), percentage fat mass, waist circumference and the android:gynoid fat mass ratio (A:G ratio) was each associated significantly with a 44.4 to 47.0% decrease in %DBV after adjustment for childhood BMI and other covariates. Although associations were weaker than for %DBV, all measures of adiposity and body fat distribution also were significantly inversely associated with ADBV before adjustment for childhood BMI. After adjustment for childhood BMI, however, only the DXA measures of percentage fat mass and A:G ratio remained significant; a SD increase in each was associated with a 13.8 to 19.6% decrease in ADBV. In mutually adjusted analysis, the percentage fat mass and the A:G ratio remained significantly inversely associated with %DBV, but only the A:G ratio was significantly associated with ADBV; a SD increase in the A:G ratio was associated with an 18.5% decrease in ADBV.
Total adiposity and body fat distribution are independently inversely associated with %DBV, whereas in mutually adjusted analysis only body fat distribution (A:G ratio) remained significantly inversely associated with ADBV in young women. Research is needed to identify biological mechanisms underlying these associations.
Antimüllerian hormone (AMH) is extensively studied in ovarian aging and pathology; however, little is known about correlates in healthy premenopausal women. We found that AMH levels are strongly inversely associated with age and differed significantly between oral contraceptive pill users and nonusers, whereas no significant associations were seen between AMH and other clinical, behavioral, and anthropometric characteristics and laboratory variables, making it an attractive hormone for clinical applications.
Müllerian-inhibiting substance (MIS); antimüllerian hormone (AMH); ovary; premenopausal; healthy
Dr. Pearl invites researchers to justify their use of principal stratification. This comment explains how the use of principal stratification simplified a complex mediational problem encountered when evaluating a smoking cessation intervention's effect on reducing smoking withdrawal symptoms.
causal inference; principal stratification; mediation; smoking cessation interventions
Combining extant datasets with differing outcome measures, an economical method to generate evidence guiding older adults’ cancer care, may introduce heterogeneity leading to invalid study results. We recently conducted a study combining extant datasets from five oncology nurse-directed clinical trials (parent studies) using norm-based scoring to standardize the differing outcome measures. The purpose of this article is to describe and analyze our methods in the recently completed study. Despite addressing and controlling for heterogeneity, our analysis found statistically significant heterogeneity (p<0.0001) in temporal trends among the five parent studies. We concluded that assessing heterogeneity in combined extant datasets with differing outcome measures is important to ensure similar magnitude and direction of findings across parent studies. Future research should include investigating reasons for heterogeneity to generate hypotheses about subgroup differences or differing measurement domains that may have an impact on outcomes.
Combining data; Older Adults; Cancer
To explore factors influencing functional status over time after cancer surgery in adults aged 65 and older.
Secondary data analysis of combined data subsets.
Five prospective, longitudinal oncology nurse-directed clinical studies conducted at three academic centers in the northwest and northeast United States.
Three hundred sixteen community-residing patients diagnosed with digestive system, thoracic, genitourinary, and gynecological cancers treated primarily with surgery.
Functional status, defined as performance of current life roles, was measured using the Enforced Social Dependency Scale and the Medical Outcomes Study 36-item Short-Form Survey (using physical component summary measures) after surgery (baseline) and again at 3 and 6 months. Number of symptoms, measured using the Symptom Distress Scale, quantified the effect of each additional common cancer symptom on functional status.
After controlling for cancer site and stage, comorbidities, symptoms, psychological status, treatment, and demographic variables, functional status was found to be significantly better at 3 and 6 months after surgery than at baseline. Factors associated with better functional status included higher income and better mental health. Factors associated with poorer average functional status were a greater number of symptoms and comorbidities. Persons reporting three or more symptoms experienced statistically significant and clinically meaningful poorer functional status than those without symptoms. Persons reporting three or more comorbidities were also found to have poorer functional status than those without comorbidities. No significant relationship existed between age and functional status in patients aged 65 and older.
Factors other than age affect recovery of functional status in older adults after cancer surgery.
functional status; older adult; cancer surgery
Elevated expression of the Nedd9/HEF1/Cas-L scaffolding protein promotes tumor cell invasion and metastasis in multiple cancer cell types. Conversely, generation of mammary tumors in the MMTV-polyoma virus middle T (PyVT) genetic model is delayed by a Nedd9−/− genotype. These activities arise from the role of Nedd9 in assembling complexes and supporting activity of cancer signaling proteins including FAK, SRC, SHC, and AKT, and would support evaluation of Nedd9 expression as an unambiguous biomarker for tumor aggressiveness. However, we here show that despite the initial delay in tumor growth, cells derived from MMTV-PyVT;Nedd9−/− tumors are characteristically hyperaggressive versus MMTV-PyVT;Nedd9+/+ cells in anchorage-independent growth, growth on 3D matrix produced by tumor-associated fibroblasts, and in formation of tumors after mammary orthotopic reinjection, and of lung metastases after tail vein injection. This reversal suggests the specific selection of MMTV-PyVT;Nedd9−/− cells for growth in an in vivo microenvironment. Indeed, MMTV-PyVT;Nedd9−/− cells have increased cell cycle, centrosomal, and mitotic defects, phenotypes compatible with the increased selection of these cells for aggressive growth. Intriguingly, in spite of their aggressive phenotype, MMTV-PyVT;Nedd9−/− cells persistently have low levels of SRC activation and are hypersensitive to the SRC kinase inhibitor dasatinib. These studies identify Nedd9 as a complex modulator of different aspects of mammary tumor growth.
A systematic review and meta-analysis to investigate the efficacy of interventions incorporating motivational interviewing for smoking cessation and identify correlates of treatment effects.
MEDLINE/PubMed, PsycInfo, and other sources including grey literature.
Title/abstract search terms were motivational interview* OR motivational enhancement AND smok*, cigarette*, tobacco, OR nicotine. Randomized trials reporting number of smokers abstinent at follow up were eligible.
Data were independently coded by the first and third authors. We coded for a variety of study, participant, and intervention related variables.
A random effects logistic regression with both a random intercept and a random slope for the treatment effect.
Thirty-one smoking cessation research trials were selected for the study: 8 comprised adolescent samples, 8 comprised adults with chronic physical or mental illness, 5 comprised pregnant/postpartum women, and 10 comprised other adult samples. Analysis of the trials (9,485 individual participants) showed an overall odds ratio comparing likelihood of abstinence in the MI versus control condition of OR=1.45, 95% Confidence Interval or CI = 1.14-1.83). Additional potential correlates of treatment effects such as study, sample, and intervention characteristics were examined.
This is the most comprehensive review of MI for smoking cessation conducted to-date. These findings suggest that current MI smoking cessation approaches can be effective for adolescents and adults. However, comparative efficacy trials could be useful.
Motivational Interviewing; Smoking Cessation; Systematic Review; Meta-Analysis
Cancer prevention clinical trials seek to enroll individuals at increased risk for cancer. Little is known about attitudes among physicians and at-risk individuals towards cancer prevention clinical trials. We sought to characterize barriers to prevention trial participation among medical oncologists and first-degree relatives of their patients.
Physician participants were practicing oncologists in Pennsylvania. Eligible first-degree participants were adult relatives of a cancer patient being treated by one of the study physicians. The influence of perceived psychosocial and practical barriers on level of willingness to participate in cancer prevention clinical trials was investigated.
Response rate was low among physicians, 137/478(29%), and modest among eligible first-degree relatives, 82/129(64%). Lack of access to an eligible population for prevention clinical trials was the most commonly cited barrier to prevention clinical trials among oncologists. Nearly half (45%) of first-degree relatives had not heard of cancer prevention clinical trials, but 68% expressed interest in learning more, and 55% expressed willingness to participate. In the proportional odds model, greater information source seeking/responsiveness (i.e. interest in learning more about clinical prevention trials from more information sources)(p=0.04), and having fewer psychosocial barriers (p=0.02) were associated with a greater willingness to participate.
Many individuals who may be at greater risk for developing cancer because of having a first-degree relative with cancer are unaware of the availability of clinical cancer prevention trials. Nonetheless, many perceive low personal risk associated with these studies, and are interested in learning more.
Cancer; prevention; clinical trials; barriers
Prospective randomized trials have demonstrated a survival benefit for nephrectomy in patients with metastatic renal cell carcinoma treated with immunotherapy. These data have been extrapolated to support cytoreductive nephrectomy in the targeted therapy era as well. However, the likelihood that patients with metastatic kidney cancer who undergo nephrectomy will receive systemic treatment postoperatively remains poorly defined. We present a multi-institutional experience evaluating the utilization of systemic therapy in patients undergoing cytoreductive nephrectomy.
PATIENTS AND METHODS
141 patients who underwent cytoreductive nephrectomy between 1990 and 2008 were identified from our Institutional Kidney Cancer Registries. Kaplan Meier analyses and Cox regression models were used to assess the impact of clinicopathological and perioperative variables on patients’ subsequent receipt of systemic therapy and postoperative survival.
Overall, 98/141 patients (69.5%) received postoperative systemic treatment, at a median of 2.5 months (range 0.1–61.5) after nephrectomy. In this group, 52 (53%) patients received immunotherapy, 34 (35%) targeted agents, and 12 (12%) other regimens. By contrast, 43 patients (30.5%) did not receive systemic therapy, because of rapid disease progression (n=13, 30%), decision for surveillance by medical oncology (n=9, 21%), patient refusal (n=10, 23%), perioperative mortality (n=8, 19%), and unknown reasons in three patients (7.0%). Median survival following cytoreductive nephrectomy was 16.7 months (range 0–120). The risk of death after surgery correlated with the number of metastatic sites (p=0.012) and symptoms (p=0.001) at presentation, poor performance status (p=0.001), high tumor grade (p=0.006), and presence of sarcomatoid features (p<0.024).
Nearly one-third of patients undergoing cytoreductive nephrectomy did not receive systemic treatment. While some were electively observed or declined therapy, others did not receive treatment due to rapidly progressive disease. Further investigation is warranted to identify those patients at highest risk for rapid post-operative disease progression who might benefit instead from an initial approach to treatment with systemic therapy.
renal cell carcinoma; metastases; nephrectomy; systemic therapy; targeted therapy
One problem with assessing effects of smoking cessation interventions on withdrawal symptoms is that symptoms are affected by whether participants abstain from smoking during trials. Those who enter a randomized trial but do not change smoking behavior might not experience withdrawal related symptoms.
We present a tutorial of how one can use a principal stratification sensitivity analysis to account for abstinence in the estimation of smoking cessation intervention effects. The paper is intended to introduce researchers to principal stratification and describe how they might implement the methods.
We provide a hypothetical example that demonstrates why estimating effects within observed abstention groups is problematic. We demonstrate how estimation of effects within groups defined by potential abstention that an individual would have in either arm of a study can provide meaningful inferences. We describe a sensitivity analysis method to estimate such effects, and use it to investigate effects of a combined behavioral and nicotine replacement therapy intervention on withdrawal symptoms in a female prisoner population.
Overall, the intervention was found to reduce withdrawal symptoms but the effect was not statistically significant in the group that was observed to abstain. More importantly, the intervention was found to be highly effective in the group that would abstain regardless of intervention assignment. The effectiveness of the intervention in other potential abstinence strata depends on the sensitivity analysis assumptions.
We make assumptions to narrow the range of our sensitivity parameter estimates. While appropriate in this situation, such assumptions might not be plausible in all situations.
A principal stratification sensitivity analysis provides a meaningful method of accounting for abstinence effects in the evaluation of smoking cessation interventions on withdrawal symptoms. Smoking researchers have previously recommended analyses in subgroups defined by observed abstention status in the evaluation of smoking cessation interventions. We believe that principal stratification analyses should replace such analyses as the preferred means of accounting for post-randomization abstinence effects in the evaluation of smoking cessation programs.
To assess reproducibility of a commercial mullerian inhibiting substance (MIS) assay and evaluate within-person variation in serum MIS levels.
Assay reproducibility was evaluated by measuring MIS in multiple serum aliquots from the same blood collection. Within-person variation was assessed by measuring MIS in serum collected twice from the same individuals.
Fox Chase Cancer Center, Philadelphia, PA
Assay reproducibility was evaluated using serum from 5 volunteers with regular menstrual cycles. Within-person variation was evaluated in serum from 20 premenopausal women who donated blood twice at least 1 year apart.
For both studies, samples were randomly ordered in batches and laboratory personnel were blinded to which aliquots were from the same subject.
Main Outcome Measure(s)
MIS was measured using an enzyme-linked immunosorbent assay.
Within- and between-batch coefficients of variation (CVs) of the assay were 7.9% and 12.3%, respectively. After deleting one subject with extreme values, these CVs decreased to 7.6% and 7.7%, respectively. Within- and between-subject variance in MIS measurements were 2.19 and 0.31, respectively, and the intraclass correlation coefficient was .88 (95% confidence interval = .77 – .98).
MIS serum concentration is relatively stable over one year in premenopausal women and can be measured with good reproducibility using a commercial kit.
Mullerian inhibiting substance (MIS); anti-mullerian hormone (AMH); assay reproducibility; coefficient of variation (CV); within-person variation; intraclass correlation coefficient (ICC)
The study used a convenience sample of patients undergoing surveillance following curative treatment for localized cancer who completed a paper survey to estimate the maximum copayment patients are willing to pay for better treatment outcomes. Results suggest that patients may be less willing to pay high copayments for treatments with modest benefit. In addition, sociodemographic factors such as education and employment status were associated with willingness to pay.
Cost sharing, intended to control the “overuse” of health care resources, may also reduce use of necessary services. The influence of cost on the treatment choices of patients with life-threatening illness, such as cancer, is unknown.
A convenience sample of patients undergoing surveillance following curative treatment for localized cancer completed a paper survey that included three scenarios to elicit the maximum copayment they would be willing to pay for better treatment outcomes. Scenario A described a treatment for a curable cancer in terms of recurrence risk. Scenarios B and C described treatments for noncurable cancer in terms of the 2-year survival probability and median life expectancy.
The sample (n = 60) was 78% female, 83% aged <65 years, and 58% college graduates. Thirteen percent reported making financial sacrifices to pay for treatment. Patients were willing to pay higher copayments for more effective treatments (p < .05 for all three scenarios). In scenario B, patients who were employed demonstrated a greater willingness to pay (WTP) (odds ratio [OR], 12.6; 95% confidence interval [CI], 2.0–80.4), when controlling for efficacy. In scenario C, college graduates showed greater WTP (OR, 5.0; 95% CI, 1.2–20.9) and patients who reported previous financial sacrifices showed lower WTP (OR, 0.2; 95% CI, 0.04–0.6).
This pilot study suggests that patients may be less willing to pay high copayments for treatments with modest benefit. Even among this relatively young, affluent, and educated population, demographic variables were related to WTP. Larger studies in more diverse populations should be conducted to better understand how cost may influence treatment decisions and cancer treatment outcomes.