<b>Objectives:</b> Recurrent, pretreated cervical carcinoma is a notoriously difficult-to-treat disease with a poor prognosis. Pembrolizumab was granted accelerated approval by the FDA in June 2018 in the setting of pretreated, recurrent, or metastatic cervical cancer based on preliminary results of the phase II basket trial KEYNOTE-158. While the reported objective response rate was only 12%, many patients exhibited a durable response, with some remaining on treatment for >12 months. We sought to examine the real-world incorporation and utilization of this treatment option and evaluate patient outcomes in an academic and safety-net county hospital system. <b>Methods:</b> Based upon timing of accelerated FDA approval and to allow for lead-in, review of institutional data identified women with pretreated recurrent, persistent, or metastatic cervical, vaginal, or vulvar carcinoma who were planned to receive pembrolizumab from 2017 to 2021. Demographics and clinical-pathologic data were collected. Duration of treatment, treatment-related adverse events, and clinical outcomes were analyzed. Patients with uterine and ovarian primary tumors, PD-L1 negative status, and those who did not receive a single cycle of treatment were excluded. <b>Results:</b> Fifty-two patients were identified, of whom 20 were included in the analysis. The median number of prior systemic lines of treatment was 1 (max 4). The objective response rate was 11.7%, with a clinical benefit rate of 47%. Overall, the median duration of treatment (mDOT) was 2.1 months (two cycles, IQR: 1-8). Among patients with progression of disease or death, mDOT was 2.1 months (two cycles, IQR: 2-3). Twenty-five percent of patients received at least ten cycles, all of whom presently remain on treatment (mDOT 13 months). Treatment was generally well-tolerated, with 25% experiencing any toxicity (majority G2 hypothyroidism). One patient suffered grade 3+ toxicity - immune-mediated colitis, which resulted in cessation of treatment after one cycle. The most common reasons for non-initiation of treatment with pembrolizumab included a loss to follow-up, PD-L1 negative tumors, or enrollment in clinical trials. <b>Conclusions:</b> Pembrolizumab is generally well-tolerated in the treatment of recurrent cervical cancer, and real-world experience is compared favorably with published clinical trial outcomes data. One- quarter of patients experienced a durable response of > 10 months with minimal toxicity.
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