Perioperative outcomes of pulmonary resection after neoadjuvant pembrolizumab in patients with non-small cell lung cancer.

Objectives: Pembrolizumab is a programmed death receptor-1 masking antibody approved for metastatic non-small cell lung cancer. This Phase 2 study (NCT02818920) of neoadjuvant pembrolizumab in non-small cell lung cancer had a primary end point of safety and secondary end points of efficacy and correlative science.

Methods: Patients with untreated clinical stage IB to IIIA non-small cell lung cancer were enrolled. Two cycles of pembrolizumab (200 mg) were administered before surgery. Standard adjuvant chemotherapy and radiation were encouraged but not required. Four cycles of adjuvant pembrolizumab were provided.

Results: Of 35 patients enrolled, 30 received neoadjuvant pembrolizumab and 25 underwent lung resection. Only 1 patient had a delay before surgery attributed to pembrolizumab; this was due to thyroiditis. All patients underwent anatomic resection and mediastinal lymph node dissection; the majority (18/25%, 72%) of patients underwent lobectomy. Of the 25 patients, 23 had an initial minimally invasive approach (92%); 5 of these were converted to thoracotomy (21.7%). R0 resection was achieved in 22 patients (88%), and major pathologic response was observed in 7 of 25 patients (28%). The most common postoperative adverse event was atrial fibrillation, affecting 6 of 25 patients (24%). Median chest tube duration and length of stay were 3 and 4 days, respectively. One patient required readmission to the hospital within 30 days. There was no mortality within 90 days of surgery.

Conclusions: In this study, pembrolizumab was safe and well tolerated in the neoadjuvant setting, and its use was not associated with excess surgical morbidity or mortality. Minimally invasive approaches are feasible in this patient population, but may be more challenging than in cases without neoadjuvant immunotherapy. Pathologic response was higher than typically observed with standard neoadjuvant chemotherapy.