Durable partial response to pembrolizumab, lenvatinib, and letrozole in a case of recurrent uterine carcinosarcoma with gene amplification.

• gene amplification occurs in 7% of uterine carcinosarcoma.•The presence of gene amplification in recurrent uterine carcinosarcoma may be targeted by aromatase inhibitors.• gene amplification may be identified through immunohistochemical staining for estrogen receptor followed by fluorescence in situ hybridization or tumor targeted gene sequencing.