['Our objective was to analyze the impact of preoperative and postresection solid tumor volumes on outcomes in 47 of 48 consecutive patients undergoing resection for malignant pleural mesothelioma who were treated prospectively and randomized to photodynamic therapy or no photodynamic therapy.', 'From July 1993 to June 1996, 48 patients with malignant pleural mesothelioma had cytoreductive debulking to 5 mm or less residual tumor by extrapleural pneumonectomy (n = 25) or pleurectomy/decortication (n = 23). Three-dimensional computed tomographic reconstructions of preresection and postresection solid tumor were prospectively performed and the disease was staged postoperatively according to the new International Mesothelioma Interest Group staging.', 'Median survival for all patients is 14.4 months (extrapleural pneumonectomy, 11 months; pleurectomy/decortication, 22 months; p2 = 0.07). Median survival for preoperative volume less than 100 was 22 months versus 11 months if more than 100 cc, p2 = 0.03. Median survival for postoperative volume less than 9 cc was 25 months versus 9 months if more than 9 cc, p2 = 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 positive nodes (median 166 cc, p2 = 0.01). Progressively higher stage was associated with higher median preoperative volume: stage I, 4 cc; stage II, 94 cc; stage III, 143 cc; stage IV, 505 cc; p2 = 0.007 for stage 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; p2 = 0.02).'] Is preoperative tumor volume associated with outcome in malignant pleural mesothelioma?