Risk Factors for Ovarian Cancer by BRCA Status: A Collaborative Case-Only Analysis.

BACKGROUND: Women with an inherited pathogenic variant in BRCA1 or BRCA2 have a greatly increased risk of developing ovarian cancer, but the importance of behavioral factors is less clear. We used a case-only design to compare the magnitude of associations with established reproductive, hormonal, and lifestyle risk factors between BRCA mutation carriers and noncarriers. METHODS: We pooled data from five studies from the Ovarian Cancer Association Consortium including 637 BRCA carriers and 4,289 noncarriers. Covariate-adjusted generalized linear mixed models were used to estimate interaction risk ratios (IRR) and 95% confidence intervals (CI), with BRCA (carrier vs. noncarrier) as the response variable. RESULTS: IRRs were above 1.0 for known protective factors including ever being pregnant (IRR = 1.29, 95% CI; 1.00-1.67) and ever using the oral contraceptive pill (1.30, 95% CI; 1.07-1.60), suggesting the protective effects of these factors may be reduced in carriers compared with noncarriers. Conversely, the IRRs for risk factors including endometriosis and menopausal hormone therapy were below 1.0, suggesting weaker positive associations among BRCA carriers. In contrast, associations with lifestyle factors including smoking, physical inactivity, body mass index, and aspirin use did not appear to differ by BRCA status. CONCLUSIONS: Our results suggest that associations with hormonal and reproductive factors are generally weaker for those with a pathogenic BRCA variant than those without, while associations with modifiable lifestyle factors are similar for carriers and noncarriers. IMPACT: Advice to maintain a healthy weight, be physically active, and refrain from smoking will therefore benefit BRCA carriers as well as noncarriers.

Germline BRCA variants, lifestyle and ovarian cancer survival.

OBJECTIVE: Women with ovarian cancer who have a pathogenic germline variant in BRCA1 or BRCA2 (BRCA) have been shown to have better 5-year survival after diagnosis than women who are BRCA-wildtype (non-carriers). Modifiable lifestyle factors, including smoking, physical activity and body mass index (BMI) have previously been associated with ovarian cancer survival; however, it is unknown whether these associations differ by germline BRCA status. METHODS: We investigated measures of lifestyle prior to diagnosis in two cohorts of Australian women with invasive epithelial ovarian cancer, using Cox proportional hazards regression to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: In the combined studies (n = 1923), there was little association between physical activity, BMI or alcohol intake and survival, and no difference by BRCA status. However, the association between current smoking status before diagnosis and poorer survival was stronger for BRCA variant carriers (HR 1.98; 95% CI 1.20-3.27) than non-carriers (HR 1.18; 95% CI 0.96-1.46; p-interaction 0.02). We saw a similar differential association with smoking when we pooled results from two additional cohorts from the USA and UK (n = 2120). Combining the results from all four studies gave a pooled-HR of 1.94 (95% CI 1.28-2.94) for current smoking among BRCA variant carriers compared to 1.08 (0.90-1.29) for non-carriers. CONCLUSIONS: Our results suggest that the adverse effect of smoking on survival may be stronger for women with a BRCA variant than those without. Thus, while smoking cessation may improve outcomes for all women with ovarian cancer, it might provide a greater benefit for BRCA variant carriers.

TRACEBACK: Testing of Historical Tubo-Ovarian Cancer Patients for Hereditary Risk Genes as a Cancer Prevention Strategy in Family Members.

PURPOSE: Tubo-ovarian cancer (TOC) is a sentinel cancer for BRCA1 and BRCA2 pathogenic variants (PVs). Identification of a PV in the first member of a family at increased genetic risk (the proband) provides opportunities for cancer prevention in other at-risk family members. Although Australian testing rates are now high, PVs in patients with TOC whose diagnosis predated revised testing guidelines might have been missed. We assessed the feasibility of detecting PVs in this population to enable genetic risk reduction in relatives. PATIENTS AND METHODS: In this pilot study, deceased probands were ascertained from research cohort studies, identification by a relative, and gynecologic oncology clinics. DNA was extracted from archival tissue or stored blood for panel sequencing of 10 risk-associated genes. Testing of deceased probands ascertained through clinic records was performed with a consent waiver. RESULTS: We identified 85 PVs in 84 of 787 (11%) probands. Familial contacts of 39 of 60 (65%) deceased probands with an identified recipient (60 of 84; 71%) have received a written notification of results, with follow-up verbal contact made in 85% (33 of 39). A minority of families (n = 4) were already aware of the PV. For many (29 of 33; 88%), the genetic result provided new information and referral to a genetic service was accepted in most cases (66%; 19 of 29). Those who declined referral (4 of 29) were all male next of kin whose family member had died more than 10 years before. CONCLUSION: We overcame ethical and logistic challenges to demonstrate that retrospective genetic testing to identify PVs in previously untested deceased probands with TOC is feasible. Understanding reasons for a family member's decision to accept or decline a referral will be important for guiding future TRACEBACK projects.

CART-WHEEL.org: An Ethically Approved Online Database for Patient-Entered Data to Facilitate Rare Cancer Research.

PURPOSE: Rare cancers are challenging for researchers, as clinicians and scientists have difficulty recruiting sufficient patient cases to power studies appropriately. Likewise, patients often are frustrated by a lack of specific information or evidence base for their cancer and, although eager to participate in research, have limited opportunities. We established CART-WHEEL.org, an online patient-entered database, to directly engage patients in the research process, collect rare cancer data, and facilitate their entry into additional research. PATIENTS AND METHODS: Patients access CART-WHEEL.org directly online. Clinical information is collected from users via a streamlined questionnaire developed collaboratively with consumer groups to ensure accessibility and relevance. Data collected include the following: patient demographics, comorbidities, and risk factors and tumor diagnostic, biomarker, and treatment history. Patients can download a medical summary for personal use; consent for research use of data; and indicate willingness to be contacted about other research or clinical trials. We describe data collected to date and its validation, and we provide examples of how CART-WHEEL.org can facilitate rare cancer research. RESULTS: From January 2010 to March 2018, 558 patients provided consent and entered their rare cancer data. One hundred distinct rare tumor types and patients from 22 countries were included. Validation of data entered by 21 patients with sarcoma against a hospital database demonstrated accuracy sufficient to facilitate future research in key fields, such as tumor site (95%) and histopathologic diagnosis (90%). Examples of CART-WHEEL-based disease-specific projects, subsequent recruitment to other rare cancer projects, and rare cancer patient cases of interest are described. CONCLUSIONS: Online platforms like CART-WHEEL.org can engage consumers directly, facilitating collection of patient-entered rare cancer data for hypothesis generation, and connect patients with researchers to enable specific rare cancer research and clinical trials.

Utilisation of systemic therapy options in routine treatment of metastatic colorectal cancer in Australia.

BACKGROUND: In the treatment of metastatic colorectal cancer (mCRC), exposure to all three active cytotoxic agents, 5-fluorouracil/capecitabine, irinotecan and oxaliplatin, improves overall survival. The addition of biologic agents (bevacizumab and cetuximab/panitumumab) further improves survival. The uptake of available systemic agents for mCRC in routine practice in Australia is poorly described. METHODS: The ACCORD database was interrogated to determine demographics, treatments and outcomes for patients diagnosed with mCRC between 1 January 2011 and 1 January 2016 at six Melbourne centres. RESULTS: About 1130 mCRC patients were identified: median age was 69 years (range 26-105); 61% had synchronous disease. KRAS status was known in 62%, of whom 49% were KRAS wild-type. At the time of analysis, 67% of all patients had commenced systemic treatment, 50% had received two or more lines of therapy and 19% of KRAS wild-type patients had received all five active drugs. Of KRAS-mutated patients, 35% had received all four Pharmaceutical Benefits Scheme-reimbursed active drugs. Patients who had not received chemotherapy included 72 patients who underwent metastasectomy alone. At a median follow up of 34 months, median overall survival was 25 months for all patients and 69 months for those who underwent metastasectomy. CONCLUSION: In this community-based cohort, 33% of patients had not received any systemic therapy for mCRC, and few patients had received all available active systemic agents. As many patients remain alive, these figures will likely increase over time. The overall survival of patients with mCRC in this community-based cohort was 25 months and not dissimilar to that achieved in recent clinical trials.