10540 Background: BRCA1-associated tumors are known to have less favorable pathological characteristics, but there is little information on whether this is also reflected in the stage at diagnosis. Methods: Clinical and pathological information was collected on 1,122 consecutive Ashkenazi Jewish breast cancer patients who were tested post-diagnosis for the BRCA1/2 mutations common in this population. Results: Of 1,122 patients, 70 (6.2%) were BRCA1 and 50 (4.5%) were BRCA2 carriers. Mean age at diagnosis was 49.9 yrs. in BRCA1 carriers (p=.0001 vs. non-carriers (NC)) vs. 52.0 yrs. in BRCA2 carriers (p=.02 vs. NC) and 56.0 yrs. in NC. Pure DCIS was less common in BRCA1 carriers (3%) than in BRCA2 carriers (8.2%) and NC (11.8%) (p=.03). Medullary carcinoma was more common in BRCA1 (9.8%) and BRCA2 carriers (6.7%) than in NC (1.5%) (p<.001). Invasive lobular carcinomas were rarer in BRCA1 (1.6%) and BRCA2 (2.2%) compared to NC (8.8%) (p=.012). Hormone receptors (HR) negative was more common in BRCA1 (62%) compared to BRCA2 carriers (21%) (p=.00006) and NC (17%) (p<0.0001). Triple negative tumors (HR and HER2 negative) were more common in BRCA1 carriers (60%) than in BRCA2 carriers (14%) and NC (8.3%) (p=0.001). High grade was more common in BRCA1 (60.4%) and BRCA2 (51.4%) carriers than in NC (36.7%, p=.001). Less favorable pathological features and younger age at diagnosis in BRCA1 carriers were reflected in a more advanced stage at diagnosis. Stage I at diagnosis was found in 34% of BRCA1 carriers (p=.05 vs. NC), 43% of BRCA2 carriers and 46% of NC, stage II in 48% of BRCA1 carriers, 41% of BRCA2 carriers and 37% of NC, and stage III in 17% of BRCA1 carriers, 13.5% of BRCA2 carriers and 13.5% of non-carriers. Conclusions: This consecutive cohort study demonstrates that breast cancers in BRCA1 carriers are characterized by more aggressive pathological features and are diagnosed at more advanced stages than in BRCA2 carriers and non-carriers. This may suggest a differential approach for prevention and surveillance in BRCA1 compared to BRCA2 carriers. No significant financial relationships to disclose.
Assessing risk of breast cancer in an ethnically South-East Asia population (results of a multiple ethnic groups study)
