HER2 Amplification in p53-Mutated Endometrial Carcinomas

SIMPLE SUMMARY: Endometrial cancers with p53 mutations tend to recur and develop metastases more frequently. From this point of view, the detection of new potential therapeutic targets such as HER2 is particularly interesting. In this study, we demonstrated that overexpression of HER2 (++ or +++) was present in 31.4% of p53-mutated endometrial carcinomas and that among these, 36.3% showed amplification of the HER2 gene by CISH (Chromogenic In Situ Hybridization). These results suggest that various anti-HER2 agents could constitute interesting future treatments in this type of cancer. ABSTRACT: p53-mutated endometrial carcinomas tend to recur and develop distant metastases. Therefore, the detection of new potential therapeutic targets such as HER2 is particularly interesting. In this retrospective study, which considered over 118 endometrial carcinomas, the p53 mutation was detected in 29.6% of cases. In these cases, the HER2 protein profile was studied via immunohistochemistry, and an overexpression of HER2 protein (++ or +++) was noted in 31.4%. The CISH technique was used in these cases to determine if gene amplification was present. In 18% of cases, the technique was not conclusive. Amplification of the HER2 gene was observed in 36.3% of cases and 36.3% of cases showed a polysomal-like aneusomy for centromere 17. Amplification was found in serous carcinomas, clear cell carcinomas and carcinosarcomas, highlighting the future potentiality of HER2-targeted therapies in these variants of aggressive carcinomas.