Evidence suggests that IL-17, a pro-inflammatory cytokine, suppresses tumor carcinogenesis; therefore, the use of IL-17 inhibitors accelerates carcinoma growth. We present a case of a perimenopausal female who was diagnosed with synchronous primary ovarian and endometrial endometrioid carcinoma following the use of secukinumab, a monoclonal antibody against IL-17. The gene discussed is IL17A; the disease is endometrial endometrioid carcinoma.