A case of lung adenocarcinoma with pulmonary hypertrophic osteoarthropathy showing pathological complete response to a pembrolizumab-containing chemoimmunotherapy

Abstract

A 65-year-old woman with prolonged cough and presumed pulmonary hypertrophic osteoarthropathy was referred to our hospital. Computed tomography showed 2 tumors larger than 3 cm in size and massive hilar lymph node enlargement in the right lung. Pathological examination of the transbronchial lung biopsy specimen showed atypical malignant cells, presumed adenocarcinoma, with 1% positivity of programmed cell death 1 ligand (PD-L1). Three courses of chemoimmunotherapy with pembrolizumab (400 mg q3w), carboplatin (AUC 5 mg/mL · min q3w), and pemetrexed (500 mg/m2 q3w) were well tolerated and brought about a quasi-complete response both of the lung tumors and lymph nodes and complete symptom relief of the pulmonary hypertrophic osteoarthropathy, finally leading to the surgical intervention, that is, lobectomy and lymph node dissection. Postoperative pathological examination showed no viable cancer foci both in the lung tumors and lymph nodes. The patient recovered uneventfully. Physicians should note the combination chemoimmunotherapy including pembrolizumab, with curative intent, to optimally treat patients with locally advanced non-small cell lung cancer (NSCLC) even if the NSCLC bears a small amount of PD-L1.