Assessing sexual exposure to oxaliplatin in vaginal secretions during FOLFOX chemotherapy: a case report

Sexual health is increasingly relevant to survivorship care among people with cancer. There is little quantitative data to inform the risk of exposure to chemotherapeutics during sex with someone receiving chemotherapy. A 54-year-old non-Hispanic white woman with Stage IIIA rectal cancer self-collected vaginal swabs and urine for 5 consecutive days during two cycles of chemotherapy. Swabs and urine were tested for intact oxaliplatin levels using hydrophilic interaction liquid chromatography (HILIC). Urine oxaliplatin levels peaked on the first day after chemotherapy and remained detectable for up to 3 days. The vaginal swab oxaliplatin levels exhibited significant degradation with freezing. Repeat testing revealed improved recovery with polysorb rather than cotton swabs. Polysorb vaginal swabs detected oxaliplatin only on day 1 after chemotherapy. On this day, the level of oxaliplatin remained at the limit of detection. Conservatively accounting for lost sample during freezing (50%) and assuming detection at the upper end of the limit of detection, we estimate that a vaginal swab could contain up to 2.5 ng of oxaliplatin chemotherapy on the first day after chemotherapy. Oxaliplatin levels from vaginal swab remained below the limit of detection thereafter. This is the first study to report that oxaliplatin levels in vaginal swabs are highest the first day after chemotherapy and undetectable thereafter. These data suggest that there is some indication for abstinence or barriers such as condoms in the immediate period after receipt of chemotherapy to reduce partner exposure during intercourse. The findings and methods reported inform future studies that seek to integrate patient-centered outcomes such as partner chemotherapy exposure into survivorship care.