Tumor doubling time: A selection factor for pulmonary resection of metastatic melanoma

Background and Objectives: Melanoma patients have a 20-27% rate of 5-year s urvival after surgical resection of pulmonary metastases. We evaluated tumo r doubling time (TDT) and other prognostic factors in an attempt to identif y candidates for pulmonary metastasectomy. Methods: Review of our large melanoma database identified 129 patients who underwent complete or partial resection of pulmonary metastases. At least t wo preoperative chest roentgenograms were available for 35 patients; these images were used by a single examiner to measure tumor width and length. Th e mean of the diameters was plotted against time on semilogarithmic paper: the slope of the line approximated tumor growth rate, and TDT was proportio nal to the inverse of the tumor growth rate. Results: For the 45 patients with a calculated TDT, median survival was 23. 1 months and 5-year survival rate was 15.6% (7/45). By multivariate analysi s, the only prognostically significant factors were TDT (P = 0.006) and typ e of pulmonary resection (P = 0.022). When TDT was <60 days, median surviva l was 16.0 months, and 5-year survival rate was zero; when TDT was greater than or equal to 60 days, median survival was 29.2 months (log-rank test; s ignificant at P < 0.0001) and 5-year survival rate was 20.7% (6/29) (P < 0. 0001). Conclusions: TDT is the most significant preoperative prognostic factor for patients undergoing pulmonary resection of metastatic melanoma. If TDT is <60 days, a preoperative neoadjuvant regimen of chemotherapy and biologic t herapy is recommended. pulmonary metastasectomy should not be attempted if TDT cannot be increased to greater than or equal to 60 days by systemic the rapy. (C) 1998 Wiley-Liss, Inc.