Major pathological response obtained after neoadjuvant chemotherapy combined with dual immunotherapy for malignant pleural mesothelioma: a case report.

Background: Malignant pleural mesothelioma (MPM) is a rare thoracic malignancy with high morbidity and mortality. A combination of systemic therapy and surgery may be a promising modality for the treatment of MPM, but evidence-based medicine is still lacking.

Case description: Here we report a case of MPM. The patient presented to hospital with cough and sputum. After ineffective symptomatic treatment, computed tomography (CT) examination suggested a malignant tumor of pleural origin. Positron emission tomography/computed tomography (PET/CT) examination suggested no lymph node metastasis or distant metastasis. The pathologic diagnosis of MPM was confirmed after CT-guided puncture biopsy. Next, she underwent 3 courses of neoadjuvant chemotherapy combined with dual immunotherapy (carboplatin and pemetrexed combined with anti-CTLA4 and anti-PD-1), resulting in significant tumor shrinkage. After obtaining the patient's consent and completing a preoperative evaluation, we modified the extrapleural pneumonectomy (EPP) and pleurectomy/decortication (P/D) by performing a lower lobe resection and partial pleurectomy of the left lung. Intraoperative rapid frozen pathology suggested that the margins of the tumor were negative and complete resection was achieved. The postoperative pathology report showed 10% residual viable tumor, so the major pathological response (MPR) was achieved after treatment.

Conclusions: MPM might respond well to neoadjuvant chemotherapy and dual immunotherapy, improving the probability of complete surgical resection and attaining an encouraging pathologic response.