Soluble Mesothelin-Related Peptides to Monitor Recurrence After Resection of Pleural Mesothelioma

Abstract

Most patients undergoing surgical resection of malignant pleural mesothelioma (MPM) will experience recurrence, and radiographic diagnosis of recurrence can be difficult in the postoperative chest. Our objective was to determine the utility of the serum biomarker soluble mesothelin-related peptide (SMRP; or mesothelin) in monitoring of the postoperative MPM patient. We retrospectively evaluated a prospectively maintained single institution clinical database. SMRP levels were evaluated preoperatively and postoperatively in patients undergoing surgical resection of MPM. One hundred two patients underwent pleurectomy/decortication (58%), extrapleural pneumonectomy (20%), chest wall resection (2%), or exploratory thoracotomy (20%) for MPM of 81% epithelial histology. Sixty percent received heated intraoperative chemotherapy and 57% received perioperative systemic chemotherapy. Patients with epithelial histology had substantially greater mean (± SD) preoperative SMRP levels (4.5 ± 7.3 nmol/L) than did patients with biphasic (1.9 ± 2.5 nmol/L) or sarcomatoid (1.2 ± 1.0 nmol/L) histology. Radiologic 3-dimensional tumor volume and tumor mesothelin gene (MSLN) expression correlated with preoperative SMRP. In patients with epithelial histology undergoing complete resection (n= 66), preoperative SMRP (3.4 ± 4.9 nmol/L) dramatically decreased immediately after operation (0.8 ± 0.5 nmol/L), and preoperative SMRP was independently associated with poor disease-free survival. Percentage of change in serial postoperative SMRP values at the best statistical cutoff at 48% revealed high predictive capability of disease recurrence with 90% sensitivity and 93% specificity (area under the curve= 0.96, p < 0.001). SMRP is a promising serum biomarker for the detection of recurrence after resection of epithelial MPM that may have value in clinical practice and should be studied in a prospective cohort.