Association of Neoadjuvant Pembrolizumab for Oral Cavity Squamous Cell Carcinoma With Adverse Events After Surgery in Treatment-Naive Patients

Importance: Pembrolizumab, a monoclonal antibody targeting programmed cell death 1, is currently approved by the US Food and Drug Administration for recurrent or metastatic head and neck squamous cell carcinoma (HNSCC). The potential neoadjuvant role of programmed cell death 1 inhibitors in primary surgical management of HNSCC and effects on surgical outcomes are poorly understood. Objective: To evaluate the incidence of postoperative adverse events in treatment-naive patients with advanced oral cavity cancer receiving neoadjuvant pembrolizumab when compared with matched controls, as part of a window-of-opportunity multi-institutional clinical trial assessing neoadjuvant pembrolizumab for locally advanced HNSCC. Design, Setting, and Participants: This retrospective cohort study at a single tertiary academic institution included treatment-naive patients with local regionally advanced oral cavity squamous cell carcinoma (OCSCC) who were undergoing surgical resection. Exposures: Patients with local regionally advanced resectable OCSCC who received neoadjuvant pembrolizumab were retrospectively reviewed for postoperative adverse events. Controls were matched by age, race, smoking status, and overall cancer stage based on historical data at the same institution. Matched-cohort analysis was performed using a McNemar test to assess differences between the groups. Main Outcomes and Measures: Incidence of adverse events following surgical resection of advanced OCSCC within 30 days of surgery and on continued follow-up. Results: A total of 64 patients (32 as part of the prospective clinical trial and 32 as controls; mean [SD] age, 59.6 [10.3] years; 28 [44%] women) were included in the analysis. Postoperative adverse events in the 32 patients receiving pembrolizumab included lymphedema (n = 20 [63%]), trismus (n = 7 [22%]), return to operating room (n = 7 [22%]), wound infection (n = 7 [22%]), fistula (n = 6 [19%]), wound dehiscence (n = 4 [13%]), flap failure (n = 3 [9%]), and hematoma (n = 2 [6%]). The matched control group demonstrated similar complication rates without considerable differences, except for trismus (n = 16 [50%]), which was greater by a difference of 28.1% (95% CI, 5.6%-50.6%) in the control group. Conclusions and Relevance: This cohort study examined surgical complications among patients with local regionally advanced OCSCC treated with neoadjuvant pembrolizumab and found that serious adverse events were similar to those in patients who underwent standard-of-care treatment. This suggests that there is no increased perioperative morbidity in the use of preoperative treatment with immunotherapy. Further prospective studies are needed to validate these findings for oral cavity cancer and other subsites of the head and neck.