In addition to guiding therapy, simultaneous DNA sequence analysis of tumor-normal pairs (“tumor-normal sequencing”) reveals inherited cancer predisposition mutations in 3% to 12.6% of pediatric and adult patients with cancer.^1-7 It remains unknown, however, how many inherited mutations would be detected by multigene tumor-normal analysis compared with a traditional family history–based approach to genetic counseling and testing, and what the clinical implications of these findings would be. Selection for genetic testing is traditionally based on pathologic features of the tumor, age at diagnosis, family history of cancer, and other factors represented in clinical practice guidelines.^8-10 Studies have not determined whether inherited mutations found by tumor-normal sequencing would have been detected by traditional approaches to selection for genetic testing.^1-5

Cancer is in large part a genetic disease in the sense that acquired (somatic) mutations in tumor DNA contribute substantially to the malignant phenotype. Massively parallel (next-generation) sequencing makes it practical to define the spectrum of mutations in an individual cancer. Clinical researchers and practicing oncologists use tumor mutation profiling to guide treatment decisions and to determine patient eligibility for studies of targeted agents.¹

Purpose: Increased prostate cancer risk has been reported for BRCA mutation carriers, but BRCA-associated clinicopathologic features have not been clearly defined. Experimental Design: We determined BRCA mutation prevalence in 832 Ashkenazi Jewish men diagnosed with localized prostate cancer between 1988 and 2007 and 454 Ashkenazi Jewish controls and compared clinical outcome measures among 26 BRCA mutation carriers and 806 noncarriers. Kruskal-Wallis tests were used to compare age of diagnosis and Gleason score, and logistic regression models were used to determine associations between carrier status, prostate cancer risk, and Gleason score. Hazard ratios (HR) for clinical end points were estimated using Cox proportional hazards models. Results: BRCA2 mutations were associated with a 3-fold risk of prostate cancer [odds ratio, 3.18; 95% confidence interval (95% CI), 1.52-6.66; P = 0.002] and presented with more poorly differentiated (Gleason score ≥7) tumors (85% versus 57%; P = 0.0002) compared with non–BRCA-associated prostate cancer. BRCA1 mutations conferred no increased risk. After 7,254 person-years of follow-up, and adjusting for clinical stage, prostate-specific antigen, Gleason score, and treatment, BRCA2 and BRCA1 mutation carriers had a higher risk of recurrence [HR (95% CI), 2.41 (1.23-4.75) and 4.32 (1.31-13.62), respectively] and prostate cancer–specific death [HR (95% CI), 5.48 (2.03-14.79) and 5.16 (1.09-24.53), respectively] than noncarriers. Conclusions: BRCA2 mutation carriers had an increased risk of prostate cancer and a higher histologic grade, and BRCA1 or BRCA2 mutations were associated with a more aggressive clinical course. These results may have implications for tailoring clinical management of this subset of hereditary prostate cancer. Clin Cancer Res; 16(7); 2115–21. ©2010 AACR.

We performed a three-phase genome-wide association study (GWAS) using cases and controls from a genetically isolated population, Ashkenazi Jews (AJ), to identify loci associated with breast cancer risk. In the first phase, we compared allele frequencies of 150,080 SNPs in 249 high-risk, BRCA1/2 mutation-negative AJ familial cases and 299 cancer-free AJ controls using χ ² and the Cochran–Armitage trend tests. In the second phase, we genotyped 343 SNPs from 123 regions most significantly associated from stage 1, including 4 SNPs from the FGFR2 region, in 950 consecutive AJ breast cancer cases and 979 age-matched AJ controls. We replicated major associations in a third independent set of 243 AJ cases and 187 controls. We obtained a significant allele P value of association with AJ breast cancer in the FGFR2 region ( P = 1.5 × 10 ⁻⁵ , odds ratio (OR) 1.26, 95% confidence interval (CI) 1.13–1.40 at rs1078806 for all phases combined). In addition, we found a risk locus in a region of chromosome 6q22.33 ( P = 2.9 × 10 ⁻⁸ , OR 1.41, 95% CI 1.25–1.59 at rs2180341). Using several SNPs at each implicated locus, we were able to verify associations and impute haplotypes. The major haplotype at the 6q22.33 locus conferred protection from disease, whereas the minor haplotype conferred risk. Candidate genes in the 6q22.33 region include ECHDC1 , which encodes a protein involved in mitochondrial fatty acid oxidation, and also RNF146 , which encodes a ubiquitin protein ligase, both known pathways in breast cancer pathogenesis.