SHOULD THE NUMBER OF PULMONARY METASTASES INFLUENCE THE SURGICAL DECISION

Objective: To assess, using a large homogeneous retrospective series, the prognostic value of the number of resected pulmonary metastases, a nd thus, to determine to what extent the number of resectable metastas es should influence the surgical decision. Methods: The survival analy sis of all patients operated on for pulmonary metastases at a single c enter, the comparisons of 2 'histologic' groups (sarcoma and carcinoma ) and, within each histologic group, of three subgroups with different numbers of resected metastases (1, 2-4, and greater than or equal to 5) were performed. The log-rank test was used to compare survival curv es. Results: Among 575 adult patients operated on with curative intent before December 1991, the first operation allowed the complete resect ion of a known number of histologically proven viable pulmonary metast ases in 230 and 151 patients with metastases from carcinoma and sarcom a, respectively. The 5- and 10-year probabilities of survival (Kaplan- Meier) were 37 and 23%, respectively in carcinoma patients, and 31 and 28%, respectively in sarcoma patients (log-rank test: ns). Only the d ifference between patients with 1 versus 2-4 metastases from carcinoma proved statistically significant (P = 0.02), with 5-year survival est imates of 41 and 25%, respectively. Beside survival, the only signific ant difference between the subgroups of patients with different number s of resected metastases was the mean interval between the diagnosis o f pulmonary metastases and the resection of pulmonary metastases, whic h was significantly longer in patients with several metastases in both histologic groups. Conclusions: In patients with resectable pulmonary metastases from sarcoma or carcinoma, the number of metastases should have little influence on the surgical decision, except for delaying t his decision in patients with several metastases until a significant i nterval, with or without treatment, has shown that metastatic disease remains resectable and confined to the lungs. (C) 1997 Elsevier Scienc e B.V.