Thoracic mesenchymal malignant tumors and programed cell death ligand‐1 status: Clinicopathologic and prognostic analysis of eight pulmonary sarcomatoid carcinomas and eight malignant mesotheliomas

• Published in: Thoracic cancer 2021-12, Vol.12 (23), p.3169-3176
• Main Authors: Otsubo, Kanji, Sakai, Hiroki, Kimura, Hiroyuki, Miyazawa, Tomoyuki, Marushima, Hideki, Kojima, Koji, Furuya, Naoki, Mineshita, Masamichi, Chosokabe, Motohiro, Koike, Junki, Saji, Hisashi
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Antigens; Apoptosis; Automation; B7-H1 Antigen - metabolism; Biomarkers, Tumor - metabolism; Biopsy; Cancer; Carcinoma, Non-Small-Cell Lung - drug therapy; Carcinoma, Non-Small-Cell Lung - metabolism; Carcinoma, Non-Small-Cell Lung - pathology; Cell death; Chemotherapy; Female; Histology; Humans; immune checkpoint inhibitor; Immune Checkpoint Inhibitors - therapeutic use; Ligands; Male; malignant pulmonary methotelioma; Medical prognosis; Medical records; Mesothelioma, Malignant - drug therapy; Mesothelioma, Malignant - metabolism; Mesothelioma, Malignant - pathology; Metastasis; Middle Aged; Monoclonal antibodies; Original; Patients; Pleural effusion; Pleural Neoplasms - drug therapy; Pleural Neoplasms - metabolism; Pleural Neoplasms - pathology; Pneumonectomy; Prognosis; programed cell death ligand‐1; pulmonary sarcomatoid carcinoma; Radiation; Retrospective Studies; Surgery; Thoracic Neoplasms - drug therapy; Thoracic Neoplasms - metabolism; Thoracic Neoplasms - pathology; Tumors
• ISSN: 1759-7706; 1759-7714
• DOI: 10.1111/1759-7714.14177

Background The current study aimed to evaluate the significance of clinicopathological factors, particularly the immunohistochemistry of programed cell death ligand‐1 (PD‐L1), in eight cases each of pulmonary sarcomatoid carcinoma (PSC) and malignant pleural mesothelioma (MPM) at our hospital. Methods From January 2004 to December 2020, a total of 16 consecutive patients (eight with PSC and eight with MPM diagnosed via surgical resection or biopsy) were included in this study. After retrospectively reviewing the patient characteristics, the associations between PD‐L1 status and age, sex, stage, histological type, and prognosis were investigated. Results PD‐L1‐positive staining was observed in four (50%) PSC cases and one (12.5%) MPM case. Among the four PD‐L1‐positive PSC cases, two showed high PD‐L1 expression in the vimentin‐positive sarcomatoid compartment. Moreover, among those with PSC, two survived for about 10 years, whereas the others died within 5 years. No clear correlation was found between PD‐L1 expression and prognosis. Among the patients with MPM, four survived for more than 2 years, with the longest being 9 years. Among MPM cases who received nivolumab, one patient with positive PD‐L1 staining in the sarcomatoid survived, whereas the other with negative PD‐L1 staining did not. Conclusion The present study showed that sarcomatoid carcinoma had a higher PD‐L1 expression compared to non‐small‐cell lung cancer and that both PSC and MPM tended to exhibit PD‐L1 positivity in the sarcomatoid compartment. Moreover, while immune checkpoint inhibitors may somewhat prolong the prognosis of both tumors, further studies with a larger cohort are necessary to confirm our results. In malignant pleural mesothelioma (MPM) and pulmonary sarcomatoid carcinoma (PSC), which are thoracic mesenchymal malignant tumors, programed cell death ligand‐1 (PD‐L1) was positive in the vimentin‐positive part or the sarcomatoid area, found to be clinicopathologically significant. In MPM, the effectiveness of immune checkpoint inhibitors (ICIs) has been shown, especially in nonepithelioid type. Our results support the possibility that ICIs will work as well as MPM if PSC is also positive for PD‐L1 and has mesenchymal features such as vimentin‐positive or sarcomatoid compartments.