Leiomyosarcoma: investigation of prognostic factors for risk-stratification model.

BACKGROUND

We performed this study to define distinctive clinical features of leiomyosarcoma by assessing prognostic factors.

METHODS

Between 1988 and 2011, 129 leiomyosarcoma patients who underwent surgical resection with curative intent were retrospectively reviewed.

RESULTS

Of the 129 leiomyosarcoma patients, the distribution of anatomic locations was: extremity (n = 25), pelvis (n = 40), thoracic cavity (n = 11), intra-abdomen (n = 19), retroperitoneum (n = 23), and head/neck (n = 11). We classified the anatomic locations into two categories as abdominal (intra-abdomen and retroperitoneum, n = 42) and extra-abdominal (extremity, pelvis, thoracic cavity, and head/neck, n = 87). Prognosis was worse for the abdominal group than for the extra-abdominal group (median DFS 2.9 9.0 years, P = 0.04). Similarly, overall survival (OS) was also significantly worse for abdominal group (P = 0.027). Independent prognostic factors for survival were primary site (P = 0.041, hazard ratio (HR) 1.7; 95 % CI 1.2-2.8), tumor size (P = 0.038, HR 1.9; 95 % CI 1.13-3.38), margin status (P = 0.019, HR 2.1; 95 % CI 1.13-3.88), and histology grade (P = 0.01, HR 3.59; 95 % CI 1.64-7.87). We identified four different risk groups with different survival outcome: group 1 (n = 8), no adverse factors; groups 2 (n = 37) and 3 (n = 61) with one and two adverse factors, and group 4 (n = 23) with 3 or 4 adverse factors.

CONCLUSION

Primary site, tumor size, resection margin, and histology subtype were independently associated with survival outcome. A prognostic model for leiomyosarcoma patients revealed four distinct groups of patients with good prognostic discrimination.