Purpose: The aim of this study is to present the prognosis and possible associated prognostic factors after curative resection of rectal leiomyosarcoma.
Methods: From 1979 to 1996 our hospital saw 40 patients with rectal leiomyosarcoma, including 19 females, who did not have metastasis initially and received curative resection and regular postoperative follow-up.
Results: The mean age of the 40 patients was 58.7 years. Anal bleeding and perianal pain were the two most common symptoms at initial diagnosis. Twenty-nine patients received a radical surgical resection, such as abdominoperineal resection or low anterior resection; the other 11 patients received a wide local excision, such as transrectal excision or Kraske's operation. Sixteen tumors were classified as high-grade leiomyosarcoma, and 23 as low grade. Nineteen patients (48 percent) developed recurrence or metastasis postoperatively (median follow-up, 35 months). The overall and disease-free (1-year, 3-year, and 5-year) survival rates were 97, 90, and 75 percent and 90, 59, and 46 percent, respectively. In univariate analysis, younger group (<50 years, n = 9, P = 0.033) and high-grade leiomyosarcoma (P = 0.043) showed poorer prognosis in the disease-free survival curve. In the multivariate Cox model, gender, tumor size, tumor location, and operation type did not significantly affect disease-free survival, whereas histologic grade (P = 0.037) and age divided by a level of 50 years (P = 0.009) were shown to be independent factors. There was a strong trend toward higher local recurrence rate for the wide local excision group than for the radical resection group (55 vs. 24 percent, P = 0.067) despite the wide local excision group being composed of smaller tumors (5.1 vs. 7.5 cm, P = 0.069). There was no difference in the incidence of distant metastasis between the two groups with different operation types. The metastasis rates of the wide local excision and radical resection groups were 27 and 38 percent, respectively.
Conclusion: A younger age (<50 years) and a high histologic grade of tumor were the two most significant poor prognostic factors for rectal leiomyosarcoma. Radical resection may be superior to wide local excision in the prevention of local recurrence but not distant metastasis.