Immunochemotherapy includes pembrolizumab for stage IIIB lung squamous cell carcinoma: a case report

Lung cancer is a malignant tumor with high morbidity and mortality, and its incidence continues to increase. With the emergence of new drugs and treatment modalities, the prognosis of lung cancer patients has improved to some extent. However, the prognosis of initially unresectable, locally advanced lung cancer with immunotherapy combined with chemotherapy remains uncertain.

We report a case of a 57-year-old man diagnosed with stage IIIB la with negative targeted therapy-related gene mutation and a 2% programmed death 1/programmed cell death-ligand 1 (PD-1/PD-L1) expression level, who underwent transformation treatment with pembrolizumab after multidisciplinary consultation. Lung images indicated partial response after 4 cycles. However, preoperative examination found hypothyroidism considered the immune-related, and giving hormone replacement treatment after the endocrinology department consultation. Thyroid function improved after 1 month. The patient successfully underwent single-hole thoracoscopic radical lung cancer (left whole lung resection + mediastinal lymph node dissection). Postoperative pathology was consistent with major pathological remission (MPR). The patient was scheduled to receive 8 cycles of single-drug maintenance therapy with pembrolizumab after surgery. To date, no tumor recurrence and metastasis have been found at follow up, and maintenance treatment continues to improve.

This case reminds us that the induction treatment pattern of pembrolizumab combined with chemotherapy for subsequent conversion surgery can be a potentially curative treatment option for locally advanced stage IIIB patients. The monitoring of thyroid-related indicators is important during immunotherapy, especially in the first 1-2 months. The cause of thyroid dysfunction should be detected early so that it can be treated promptly to improve the prognosis of the patient. Pembrolizumab in combination with paclitaxel and platinum drugs provides a new option for patients with locally advanced stage IIIB lung squamous cell carcinoma who eager to undergo radical surgery.