Background: Ovarian cancer is the 5th deadliest cancer among US women. Although clinical characteristics (e.g., stage at diagnosis and histology) and treatment (e.g., optimal debulking) predict outcomes, little is known about the contributions of modifiable factors to ovarian cancer prognosis. We evaluated whether use of analgesics (aspirin; other non-steroidal anti-inflammatory drugs [NSAIDs], including ibuprofen, naproxen, and coxibs; and acetaminophen) were associated with improved ovarian cancer prognosis.

Methods: The Nurses' Health Study (NHS) is a prospective study of 121,700 US nurses who have completed biennial questionnaires on lifestyle, medications, and disease diagnosis since 1976. Among NHS participants diagnosed with ovarian cancer, we evaluated whether pre- and post-diagnosis use of aspirin, other NSAIDs, or acetaminophen was associated with risk of dying due to any cause or due to ovarian cancer. Regular aspirin use (more than 2 times/week over the prior year) was queried on every questionnaire since 1980; regular use of other NSAIDs or acetaminophen has been queried since 1990. We used Cox proportional hazards regression to calculate relative risks (RRs) and 95% confidence intervals (CI), adjusting for tumor and personal characteristics (stage, histology, invasiveness, age at diagnosis, year of diagnosis, adiposity, smoking, menopause status, oral contraceptive use, parity, tubal ligation, and family history). Women with diagnosed with stage IV ovarian cancer were excluded from the analysis.

Results: 865 ovarian cancer patients had data available on pre-diagnosis aspirin; 649 had data on pre-diagnosis use of other NSAIDs and acetaminophen. For post-diagnosis exposures, 602 women had information on post-diagnosis use of aspirin and 491 had information on post-diagnosis use of other NSAIDs/acetaminophen available. Women who regularly used aspirin after diagnosis had a 35% lower risk of death (RR: 0.65; 95% CI: 0.45-0.92) and a 44% lower risk of dying due to ovarian cancer (RR:0.56; 95% CI: 0.36-0.86). Post-diagnosis use of other NSAIDs was associated with a suggestive decreased risk of ovarian cancer death (RR: 0.86; 95% CI: 0.59-1.26). There was no association of pre-diagnosis use of any of the analgesic medications with prognosis, nor was there an association of post-diagnosis acetaminophen use with survival.

Conclusion: In this preliminary study of analgesic use among ovarian cancer patients, regular use of aspirin after diagnosis appeared to improve survival. However, there were relatively few current users available for analysis, particularly for non-aspirin NSAIDs (131 women were current users; 66 of whom died during follow-up). Overall, our results suggest that reducing inflammation after diagnosis may be beneficial for improving survival. Additional analyses on patterns of analgesic use (e.g., duration of use and frequency) are on-going, as well as additional data from the Nurses' Health Study II. Further analyses stratifying by stage and histology will also be conducted.

Citation Format: Elizabeth M. Poole, Megan S. Rice, Shelley S. Tworoger. Pre- and postdiagnosis analgesic use and ovarian cancer survival. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: Exploiting Vulnerabilities; Oct 17-20, 2015; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(2 Suppl):Abstract nr B29.