However, it is difficult to directly compare the two studies

ibed in previous studies. Five new BRCA1 mutant ovarian tumors and four new BRCA2 mutant ovarian tumors were analyzed compared to the previous studies. Using this updated data, we reevaluated the survival of ovarian patients with BRCA1/2 mutation and wild-type patients, and revealed different result compared with previous findings. We found that, not only BRCA2 mutation carriers, but also BRCA1 mutation carriers had significantly improved survival than wild-type ovarian cancer patients. The 5-year survival rate of BRCA1 and BRCA2 mutation carriers was 46% and 58% respectively, which was significantly higher than 25% 5-year survival rate in wild-type patients. The progressionfree interval of BRCA1/2 mutation carriers was also significantly longer than wildtype patients in the multivariate analysis. Genomic instability score in predicting outcome of BRCA mutation carriers To PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/19691102/ explore the genomic instability of BRCA mutated and wild-type ovarian cancer patients, we calculated the frequency of somatic mutation and the frequency of CNC for each tumor genome. Tumors with germline and somatic BRCA mutations had no significant differences in outcomes and in genomic instability, and thus were CJ-023423 pooled together in down-stream analyses. Both BRCA1 and BRCA2 mutated genome showed elevated level of mutation and CNC frequency, being consistent with our hypothesis that HR-deficient pathway leads to an increase of mutation and chromosomal instability. We further noticed that 5 / 16 Genome Instability Predicts Ovarian Cancer Outcome BRCA2 mutated tumors had higher genomic instability than BRCA1-disrupted tumors, suggesting that BRCA2 mutation carriers exhibited a more severe HR deficiency than BRCA1 mutation carriers. This was consistent with the higher survival rate of BRCA2 mutation carriers compared with that of BRCA1 mutation carriers. We hypothesized that genomic instability reflects HR deficiency. Based on this hypothesis, ovarian cancer patients carrying BRCA mutations were divided into two groups by comparing mutation rate and CNC PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/19692133 frequency with the respective median level of wild-type patients. BRCA mutation carriers in the high level group of both mutation and CNC showed significantly improved overall survival than wild-type patients. In contrast, overall survival of BRCA mutation carriers in the low level group of both mutation and CNC was not significantly different from wild-type patients. Although the low level group of CNC achieved significance in adjusted model, the significance is dramatically lower than the high level group of CNC. The significant prognostic value of genomic instability inspired us to develop a score integrating mutation and CNC to identify HR deficient ovarian tumors. The score of ovarian cancer patients with BRCA1/2 mutation was significantly higher than wild-type patients. BRCA mutated tumors were then divided into the high score group and the low score group by comparing their scores with the median level of scores of wild-type patients. 30 BRCA1 and 21 BRCA2 mutation carriers were divided into the high score group, whereas 12 BRCA1 and 12 BRCA2 mutation carriers were divided into the low score group. Tumors in the high level 6 / 16 Genome Instability Predicts Ovarian Cancer Outcome group had significantly higher 5-year survival rate than wild-type patients, whereas tumors in the low level group had no significant difference in survival compared with wild-type patients. Genomic instability score is correlated with HR