Although ovarian cancers appear to be immunologically active, they do not respond well to immunotherapy in the clinic. In a study published on Dec. 14, 2022, in Nature, a multidisciplinary team at Memorial Sloan Kettering Cancer Center (MSK) led by Sohrab Shah and Dmitriy Zamarin has uncovered several mechanisms of immune evasion that can help explain why ovarian cancers have been resistant to immunotherapy to date.