PREOPERATIVE TUMOR VOLUME IS ASSOCIATED WITH OUTCOME IN MALIGNANT PLEURAL MESOTHELIOMA

Objectives: Our objective was to analyze the impact of preoperative an d postresection solid tumor volumes on outcomes in 47 of 48 consecutiv e patients undergoing resection for malignant pleural mesothelioma who were treated prospectively and randomized to photodynamic therapy or no photodynamic therapy. Methods: From July 1993 to June 1996, 48 pati ents with malignant pleural mesothelioma had cytoreductive debulking t o 5 mm or less residual tumor by extrapleural pneumonectomy (n = 25) o r pleurectomy/decortication (n = 23). Three-dimensional computed tomog raphic reconstructions of preresection and postresection solid tumor w ere prospectively performed and the disease was staged postoperatively according to the new International Mesothelioma Interest Group stagin g. Results: Median survival for all patients is 14.4 months (extrapleu ral pneumonectomy, 11 months; pleurectomy/decortication, 22 months; p( 2) = 0.07), Median survival for preoperative volume less than 100 was 22 months versus 11 months if more than 100 cc, p(2) = 0.03, Median su rvival for postoperative volume less than 9 cc was 25 months versus 9 months if more than 9 cc, p(2) = 0.0002. Thirty-two of forty-seven (68 %) had positive N1 or N2 nodes. Tumor volumes associated with negative nodes were significantly smaller (median 51 cc) than those with posit ive nodes (median 166 cc, p(2) = 0.01), Progressively higher stage was associated with higher median preoperative volume: stage I, 4 cc; sta ge II, 94 cc; stage III, 143 cc; stage IV, 505 cc; p(2) = 0.007 for st age I versus II versus III versus IV. Patients with preoperative tumor volumes greater than 52 cc had shorter progression-free intervals (8 months) than those 51 cc or less (11 months; p(2) = 0.02). Conclusions : Preresection tumor volume is representative of T status in malignant pleural mesothelioma and can predict overall and progression-free sur vival, as well as postoperative stage. Large volumes are associated, w ith nodal spread, and postresection residual tumor burden may predict outcome.