Ovarian cancer resistance to PARPi and platinum-containing chemotherapy.

Epithelial ovarian cancer remains the most lethal female malignancy despite options for systemic therapy and the emergence of targeted therapies. Although initial response to therapy is observed, recurrence and ultimately chemoresistance result in overall therapeutic failure. This pattern has been evident with platinum therapy since the 1980s. Significant excitement surrounded the approval of poly (ADP-ribose) polymerase inhibition (PARPi) as a novel therapeutic option, especially with the advent of personalized medicine, but resistance has similarly developed to these treatments. Novel agents are constantly being sought, but if the obstacle of chemoresistance remains, the durability of responses will remain tenuous. Unraveling the multifactorial mechanisms of platinum and PARPi resistance is increasingly important as a therapeutic failure with current strategies is almost assured. Focusing greater efforts on expanding the current understanding of the complex nature of platinum and PARPi chemoresistance has tremendous potential to improve clinical outcomes.