Prognostic implications of patterns of failure for gastrointestinal leiomyosarcomas.

One hundred ninety-one patients with gastrointestinal leiomyosarcomas were analyzed to determine the prevalence in patterns of failure and the factors predicting those at higher risk of relapse at specific sites. Of 100 assessable patients who died of disease, 89% were found to have peritoneal tumor, 78% had liver metastases, and 32% had extraabdominal metastases. Of 132 patients (69%) with initial complete resection of the primary tumor, only 10% (n = 13) remained free of disease as of the last follow-up. The median interval to recurrence was 18 months; 60% of all recurrences occurred within 2 years after surgery. Half of these patients (n = 61) had metastases (predominantly in the liver) as the initial recurrence. Factors significantly associated with improved survival after relapse were initial disease-free interval of 18 months or more, recurrences either isolated to the peritoneal cavity or within the liver, or complete resection of peritoneal recurrences or liver metastases. In contrast, those patients with recurrences at multiple sites or unresectable disease had significantly shorter survival times. The presence of extraabdominal metastases also heralded an equally poor outcome. In conclusion, a multimodality approach is necessary to improve outcome from this disease because the liver and peritoneal cavity represent predominant sites of failure. Complete resection of isolated peritoneal or hepatic metastases improves survival and should be attempted when feasible.