e16070 Background: The management of the clear cell renal cell carcinoma (cc-RCC) has evolved over the past decade. Clinical patients’ and tumor characteristics have a limited role in predicting the outcome of these patients. The search for reliable prognostic and predictive biomarkers should be pursued in particular during the current era of next generation sequencing (NGS) technology. Methods: Formalin-Fixed Paraffin-Embedded (FFPE) tissue specimens of cc-RCC were sequenced using NGS and a customized gene panel testing for 72 tumor-related genes. High potential variants were defined by mutation effect (stop-loss, stop-gain, frame-shift substitutions or non-synonymous SNV) and class (pathogenic or likely pathogenic). Cases with identical variants were identified. Results: In total, all 47 cases had 69,052 variants, of which 20,453 were classified as high potential variants. Identical alterations in 15 genes were present in all samples. These genes are: MUC3A, MUC12, MUC7, SRRT, MUC2, MUC5AC, MUC5B, MUC22, MUC6, CR1, MUC4, MUC16, MUC19, MUC17 and MERTK. The numbers of identical and non-identical variants in these 15 genes were counted for each sample. Median number of variants was 377 and was selected as a cut off to define cases with high ( > 377) and low (≤377) variants number (HVN and LVN respectively). For the whole cohort, HVN was associated with shorter overall survival compared to LVN (Median 50 months vs. not reached; Log Rank P = 0.041). In the 11 patients who received anti-angiogenic tyrosine kinase inhibitors (TKIs), HVN was associated with a trend of shorter progression free survival (Median 5 vs. 10 months; Log Rank P = not significant). Conclusions: Alterations in SRRT, CR1, MERTK and MUCIN family genes are very common in RCC. HVN ( > 377) is associated with worse prognosis and may predict decreased benefit from anti-angiogenic TKIs.
Identification of somatic genetic alterations in ovarian clear cell carcinoma with next generation sequencing
