Does mediastinal lymph node involvement influence the surgical outcome in malign pleural mesothelioma?

This study examined the effect of metastatic mediastinal lymph node involvement on the prognosis of patients with malignant pleural mesothelioma (MPM) who underwent extrapleural pneumonectomy (EPP) or extended pleurectomy (E/P) and also to assess the effect of metastatic mediastinal lymph node involvement on the prognosis of patients with MPM in these group of patients.

This retrospective study included 84 patients with MPM (66 men [78.6%] and 18 women [21.4%]) who underwent EPP (n = 44) or E/P (n = 40) at our institution between January 2001 and July 2019. Survival analyses were performed according to histopathology, nodal status, and surgical approach.

In the EPP group, patients with T2-N2 status had a significantly better mean survival (17 ± 2.1 months) than patients with T3-N2 (7.3 ± 1.6 months) or T4-N2 (3.2 ± 1.1 months) status (p = .001). In the E/P group, patients with T2-N2 status had a mean survival of 18 ± 1.1 months, while patients with T3-N2 and T4-N2 status had mean survival durations of 6.6 ± 1.6 and 4.8 ± 1.2 months, respectively (p = .159). In both treatment groups, the survival rates of patients with epithelial tumors were better than those of patients with non-epithelial tumors, independent of N status. None of the patients with N2 disease survived until 5 years postoperatively.

In summary, our results suggested that mediastinal lymph node metastasis negatively influenced the prognosis of patients with T3 MPM, regardless of treatment by EPP or E/P. Under these circumstances, preoperative cervical mediastinoscopy or endobronchial ultrasound-guided transbronchial needle aspiration may be considered for patients with high-stage MPM who are scheduled for surgery with curative intent. In our study, N2 status was spotted as a significant factor affecting survival, nevertheless its significance in survival of pleural mesothelioma patients should be analyzed in multi-centered studies.