Surgical indications for pleurectomy/decortication in pleural mesothelioma based on the newly revised 9th edition of the tumour-node-metastasis classification.

Objectives: The MARS2 trial questioned the efficacy of curative intent surgery for pleural mesothelioma (PM), while real-world clinical data from Japan suggest a favourable prognosis in surgical cases, indicating survival benefits in selected patients. The newly revised 9th edition of the tumour-node-metastasis (TNM) classification introduces a novel indicator based on pleural thickness.

Methods: We conducted a retrospective evaluation of patients with PM who underwent pleurectomy/decortication between 2012 and 2022. Patient characteristics, complications and treatment outcomes were assessed. Additionally, outcomes were analysed based on the 9th edition of the TNM classification.

Results: A total of 62 patients were included in the analysis. The median overall survival (OS) was 37.3 months, with a median relapse-free survival (RFS) of 15.5 months. Patients with the epithelioid subtype (OS: 61.6 months; RFS: 26.0 months) and pStage IA (OS: not reached; RFS: 69.1 months) had significantly better outcomes. The 9th edition of the TNM classification showed a stronger prognostic correlation than the 8th edition, with a median OS of 77.0, 31.9, 20.4 and 25.3 months for stages I, II, IIIA and IIIB (P = 0.0016) and median RFS of 34.3, 12.3, 13.7 and 6.9 months for stages I, II, IIIA and IIIB (P = 0.013), respectively.

Conclusions: Surgical intervention remains crucial in the treatment of PM, particularly for patients with epithelioid histology and early stages of the disease. This study evaluates surgical indications for PM using the newly revised 9th edition of the TNM classification, indicating that it enhances the precision of surgical candidate selection and potentially improves patient outcomes.