Valerie S. Lee

Wine and other alcohol consumption and risk of ovarian cancer in the California Teachers Study cohort

ObjectiveWhether alcohol consumption influences ovarian cancer risk is unclear. Therefore, we investigated the association between alcohol intake at various ages and risk of ovarian cancer.MethodsAmong 90,371 eligible members of the California Teachers Study cohort who completed a baseline alcohol assessment in 1995–1996, 253 women were diagnosed with epithelial ovarian cancer by the end of 2003. Multivariate Cox proportional hazards regression analysis was performed to estimate relative risks (RRs) and 95% confidence intervals (CIs).ResultsConsumption of total alcohol, beer, or liquor in the year prior to baseline, at ages 30–35 years, or at ages 18–22 years was not associated with risk of ovarian cancer. Consumption of at least one glass per day of wine, compared to no wine, in the year before baseline was associated with increased risk of developing ovarian cancer: RR = 1.57 (95% CI 1.11–2.22), Ptrend = 0.01. The association with wine intake at baseline was particularly strong among peri-/post-menopausal women who used estrogen-only hormone therapy and women of high socioeconomic status.ConclusionsAlcohol intake does not appear to affect ovarian cancer risk. Constituents of wine other than alcohol or, more likely, unmeasured determinants of wine drinking were associated with increased risk of ovarian cancer.

Reliability and Validity of an Assessment of Usual Phytoestrogen Consumption (United States)

Objective To evaluate the reliability and validity of a food-frequency questionnaire (FFQ) and database designed to quantify phytoestrogen consumption.Methods This study included 195 members of the California Teachers Study (CTS) cohort who, over a 10-month period, completed four 24-h dietary recalls, a pre- and post-study FFQ, and provided two 24-h urine specimens. Participants (n=106) in a parallel study (and 18 women who dropped out of the long-term study) completed a single recall and FFQ, and provided one 24-h urine specimen. Urinary phytoestrogens were determined using liquid chromatography–mass spectrometry. Reliability and validity were evaluated using Shrout–Fleiss intraclass correlations and energy-adjusted deattenuated Pearson correlations, respectively.Results Correlations reflecting the reproducibility of the FFQ phytoestrogen assessment ranged from 0.67 to 0.81. Validity correlations (FFQ compared to dietary recalls) ranged from 0.67 to 0.79 for the major phytoestrogenic compounds (i.e., daidzein, genistein, and secoisolariciresinol) and 0.43 to 0.54 for the less common compounds. Compared to urinary levels, validity correlations ranged from 0.41 to 0.55 for the isoflavones and 0.16 to 0.21 for total lignans.Conclusion Our isoflavone assessment is reproducible, valid, and an excellent tool for evaluating the relationship with disease risk in non-Asian populations. Further research is needed before these tools can accurately be used to assess lignan consumption.

Diabetes and other comorbidities in breast cancer survival by race/ethnicity: The California Breast Cancer Survivorship Consortium (CBCSC)

Background: The role of comorbidities in survival of patients with breast cancer has not been well studied, particularly in non-white populations. Methods: We investigated the association of specific comorbidities with mortality in a multiethnic cohort of 8,952 breast cancer cases within the California Breast Cancer Survivorship Consortium (CBCSC), which pooled questionnaire and cancer registry data from five California-based studies. In total, 2,187 deaths (1,122 from breast cancer) were observed through December 31, 2010. Using multivariable Cox proportional hazards regression, we estimated HRs and 95% confidence intervals (CI) for overall and breast cancer–specific mortality associated with previous cancer, diabetes, high blood pressure (HBP), and myocardial infarction. Results: Risk of breast cancer–specific mortality increased among breast cancer cases with a history of diabetes (HR, 1.48; 95% CI, 1.18–1.87) or myocardial infarction (HR, 1.94; 95% CI, 1.27–2.97). Risk patterns were similar across race/ethnicity (non-Latina white, Latina, African American, and Asian American), body size, menopausal status, and stage at diagnosis. In subgroup analyses, risk of breast cancer–specific mortality was significantly elevated among cases with diabetes who received neither radiotherapy nor chemotherapy (HR, 2.11; 95% CI, 1.32–3.36); no increased risk was observed among those who received both treatments (HR, 1.13; 95% CI, 0.70–1.84; Pinteraction = 0.03). A similar pattern was found for myocardial infarction by radiotherapy and chemotherapy (Pinteraction = 0.09). Conclusion: These results may inform future treatment guidelines for patients with breast cancer with a history of diabetes or myocardial infarction. Impact: Given the growing number of breast cancer survivors worldwide, we need to better understand how comorbidities may adversely affect treatment decisions and ultimately outcome. Cancer Epidemiol Biomarkers Prev; 24(2); 361–8. ©2014 AACR.

Dietary Patterns and Risk of Ovarian Cancer in the California Teachers Study Cohort

Previous studies have examined the association between individual foods or nutrients, but not overall diet, and ovarian cancer risk. To account for the clustering of foods in the diet, we investigated the association between dietary patterns and risk of ovarian cancer in the prospective California Teachers Study cohort. Of 97,292 eligible women who completed the baseline dietary assessment in 1995–1996, 311 women developed epithelial ovarian cancer on or before December 31, 2004. Based on principal components analysis, 5 major dietary patterns were identified and termed plant-based, high-protein/high-fat, high-carbohydrate, ethnic, and salad-and-wine. Multivariable Cox proportional hazards regression analysis was used to estimate associations between these dietary patterns and risk of incident ovarian cancer. Most of the dietary patterns were not significantly associated with ovarian cancer risk. However, women who followed a plant-based diet had higher risk; comparing those in the top quintile of plant-based food intake with those in the lowest quintile, the relative risk of ovarian cancer was 1.65 (95% confidence interval = 1.07–2.54; P trend = 0.03). Associations with the 5 dietary patterns did not vary by known ovarian cancer risk factors or other behavioral or sociodemographic characteristics. Overall, our results show no convincing associations between dietary patterns and ovarian cancer risk.

Impact of Chemotherapy Dosing on Ovarian Cancer Survival According to Body Mass Index

IMPORTANCE Optimal chemotherapy dosing in obese patients remains uncertain, with variation in practice. Dose reduction strategies are often used to avoid chemotoxicity, but recent American Society of Clinical Oncology guidelines recommend full dose. OBJECTIVE To evaluate the impact of body mass index (BMI) on chemotherapy dosing and of dose reduction on ovarian cancer survival. DESIGN, SETTING, AND PARTICIPANTS Cohort study in Kaiser Permanente Northern California (KPNC) health care setting of patients with primary invasive epithelial ovarian cancers diagnosed from January 2000 through March 2013. Analyses focused on 806 patients receiving adjuvant first-line therapy of carboplatin and paclitaxel with curative intent. MAIN OUTCOMES AND MEASURES Overall and ovarian cancer-specific mortality. Deaths were identified through the KPNC Mortality Linkage System, with median follow-up of 52.5 months. Hazard ratios (HRs) and 95% CIs were estimated from proportional hazards regression, accounting for prognostic variables including age at diagnosis, race, stage, grade, histologic type, chemotoxic effects, comorbidities, cancer antigen 125 levels, and BMI at diagnosis. RESULTS The strongest predictor of dose reduction was a high BMI. Compared with normal-weight women, obese class III women received 38% and 45% lower doses in milligrams per kilogram of body weight of paclitaxel and carboplatin, respectively (P < .001 for each agent). They also received lower relative dose intensity (RDI) for each agent and the combined regimen, calculated as average RDI (ARDI). Mean ARDI was 73.7% for obese class III women and 88.2% for normal-weight women (P < .001). Lower ARDI (<70%) was associated with worse overall (HR, 1.62 [95% CI, 1.10-2.37]) and ovarian cancer-specific survival (HR, 1.69 [95% CI, 1.12-2.55]). Women who were obese at diagnosis appeared to have better survival. In multivariable-adjusted analyses considering joint effects by BMI and ARDI, compared with women with normal weight and no dose reduction, normal-weight women with dose reduction (ARDI < 85%) experienced worse survival (HR, 1.50 [95% CI, 1.02-2.21]). For each BMI category, those with ARDI less than 85% had worse survival than those without dose reduction. The improved survival among obese women was no longer apparent with dose reduction. CONCLUSIONS AND RELEVANCE Lower RDI was an independent predictor of ovarian cancer mortality. This finding was strongest among normal-weight women but seen at all levels of BMI. Our results suggest that body size should not be a major factor influencing dose reduction decisions in women with ovarian cancer.

Racial/Ethnic Disparities in Ovarian Cancer Treatment and Survival

Purpose: Among patients with ovarian cancer, African American (AA) women experience poorer survival compared with other race/ethnicity groups. This has been attributed to differences in access to health care. Experimental Design: We evaluated racial/ethnic differences in chemotherapy dosing and survival in a cohort study among members of Kaiser Permanente Northern California, and thus with equivalent access to health care. Analyses included epithelial-invasive ovarian cancer cases (n = 793) receiving adjuvant first-line therapy of carboplatin and paclitaxel with curative intent, with median follow-up of 50 months. Relative dose intensity (RDI) was computed for carboplatin and paclitaxel separately as dose administered per week divided by expected dose per week, and average RDI (ARDI) was then calculated for the regimen. Proportional hazards regression was used to calculate HRs and 95% confidence intervals (CIs) after adjusting for relevant covariates. Results: Compared with whites, AAs were more likely to have dose reduction (ARDI < 85%), treatment delay, and early discontinuation. Hispanics were also more likely to have dose reduction, but less likely to have early discontinuation or treatment delay. After controlling for prognostic factors including ARDI, AA women had the worst survival. Compared with whites, adjusted HRs (95% CI) for overall mortality were 1.56 (1.01–2.39) for AAs; 0.89 (0.61–1.31) for Asians; and 1.41 (0.98–2.04) for Hispanics. Findings for ovarian cancer–specific mortality were similar. Conclusions: Disparities in ovarian cancer treatment and survival in AA persisted among women with equal access to care. These findings warrant further evaluation of biological, personal, and social factors that may be responsible for these differences. Clin Cancer Res; 22(23); 5909–14. ©2016 AACR.

History of Recreational Physical Activity and Survival After Breast Cancer The California Breast Cancer Survivorship Consortium

Recent epidemiologic evidence suggests that prediagnosis physical activity is associated with survival in women diagnosed with breast cancer. However, few data exist for racial/ethnic groups other than non-Latina whites. To examine the association between prediagnosis recreational physical activity and mortality by race/ethnicity, we pooled data from the California Breast Cancer Survivorship Consortium for 3 population-based case-control studies of breast cancer patients (n=4,608) diagnosed from 1994 to 2002 and followed up through 2010. Cox proportional hazards models provided estimates of the relative hazard ratio for mortality from all causes, breast cancer, and causes other than breast cancer associated with recent recreational physical activity (i.e., in the 10 years before diagnosis). Among 1,347 ascertained deaths, 826 (61%) were from breast cancer. Compared with women with the lowest level of recent recreational physical activity, those with the highest level had a marginally decreased risk of all-cause mortality (hazard ratio=0.88, 95% confidence interval: 0.76, 1.01) and a statistically significant decreased risk of mortality from causes other than breast cancer (hazard ratio=0.63, 95% confidence interval: 0.49, 0.80), and particularly from cardiovascular disease. No association was observed for breast cancer-specific mortality. These risk patterns did not differ by race/ethnicity (non-Latina white, African American, Latina, and Asian American). Our findings suggest that physical activity is beneficial for overall survival regardless of race/ethnicity.

Validation of AJCC TNM staging for breast tumors diagnosed before 2004 in cancer registries

PurposeAmerican Joint Committee on Cancer (AJCC) Tumor (T), Nodal (N), and Metastatic (M) staging is commonly used in clinical practice for treatment decisions, yet before 2004, Surveillance Epidemiology and End Results (SEER)-affiliated cancer registries did not routinely include TNM staging defined by AJCC criteria, reporting instead SEER Summary Staging.MethodsWe developed and validated an algorithm to determine AJCC TNM staging from Extent of Disease information for 17,133 female breast cancer cases diagnosed from 1988 to 2003 in the cancer registries of Kaiser Permanente Northern and Southern California. Test characteristics (percent agreement, Cohen’s kappa, sensitivity, specificity) were calculated to compare derived TNM with gold-standard TNM available in the registry.ResultsAgreement for TNM variables was excellent (range 0.91–1.00 for percent agreement and Cohen’s kappa). The sensitivity and specificity, respectively, of the algorithm for AJCC TNM Version 6 staging were as follows: Stage 0 (0.99, 1.00), Stage I (0.97, 0.98), Stage II (0.91, 0.96), Stage III (0.69, 0.99), and Stage IV (0.92, 1.00). Stage III had lower sensitivity due to reclassification of supraclavicular lymph node positivity from M1 (Stage IV) to N3 (Stage IIIC) in AJCC Version 6.ConclusionsDerived AJCC staging for breast tumors diagnosed before 2004 is feasible and accurate using cancer registry data.

A hybrid approach to identify subsequent breast cancer using pathology and automated health information data.

Purpose:Many cancer registries do not capture recurrence; thus, outcome studies have often relied on time-intensive and costly manual chart reviews. Our goal was to build an effective and efficient method to reduce the numbers of chart reviews when identifying subsequent breast cancer (BC) using pathology and electronic health records. We evaluated our methods in an independent sample. Methods:We developed methods for identifying subsequent BC (recurrence or second primary) using a cohort of 17,245 women diagnosed with early-stage BC from 2 health plans. We used a combination of information from pathology report reviews and an automated data algorithm to identify subsequent BC (for those lesions without pathologic confirmation). Test characteristics were determined for a developmental (N=175) and test (N=500) set. Results:Sensitivity and specificity of our hybrid approach were robust [96.7% (87.6%–99.4%) and 92.1% (85.1%–96.1%), respectively] in the developmental set. In the test set, the sensitivity, specificity, and negative predictive value were also high [96.9% (88.4%–99.5%), 92.4% (89.4%–94.6%), and 99.5% (98.0%–99.0%), respectively]. The positive predictive value was lower (65.6%, 55.2%–74.8%). Chart review was required for 10.9% of the 17,245 women; 2946 (17.0%) women developed subsequent BC over a 14-year period. The date of subsequent BC identified by the algorithm was concordant with full chart reviews. Conclusions:We developed an efficient and effective hybrid approach that decreased the number of charts needed to be manually reviewed by approximately 90%, to determine subsequent BC occurrence and disease-free survival time.

Impact of body mass index on ovarian cancer survival varies by stage

Background:Research on the effect of body mass index (BMI) on ovarian cancer survival is inconsistent, but previous studies did not consider the possible impact of ascites, bowel obstruction, or cachexia, which commonly occur in late-stage disease.Methods:We evaluated the association of BMI, before and around the time of diagnosis, with overall and disease-specific survival in a cohort study of primary invasive epithelial ovarian cancers diagnosed from 2000 to 2013 in Kaiser Permanente Northern California (KPNC) (n=1184). Deaths were identified through December 2014, with a median follow-up of 37 months. Proportional hazards regression was used to estimate overall and ovarian cancer-specific mortality, accounting for prognostic variables including age at diagnosis, race, stage, grade, histology, comorbidities, treatment, post-treatment CA125 levels, ascites, and bowel obstruction.Results:There was no evidence of an association between BMI and overall or ovarian cancer-specific survival. However, we found strong effect modification by stage (Pinteraction<0.01). Compared with normal prediagnosis BMI (18.5–24.9 kg m−2), for women who were obese before diagnosis (BMI⩾35 kg m−2) ovarian cancer-specific survival was lower among those diagnosed at stages I/II (hazard ratio (HR): 3.40; 95% confidence interval (CI): 1.16–9.99), but increased among those diagnosed with stage IV disease (HR: 0.58; 95% CI: 0.35–0.96). Associations were attenuated after excluding those diagnosed with cachexia (n=82) and further adjustment for ascites and bowel obstruction, with no evidence of effect modification by these factors.Conclusions:Associations of obesity with ovarian cancer survival may differ by stage, with decreased survival among those with localised disease and increased survival among those with late-stage disease. Stage-specific effects of obesity on survival suggest a tailored approach to improve prognosis may be appropriate.