Prognostic Factors Influencing Survival in Gastrointestinal Leiomyosarcomas Implications for Surgical Management and Staging

Abstract

The appropriate surgical therapeutic options for either localized or more advanced disease in patients with gastrointestinal leiomyosarcomas remain unclear. A staging classification for this disease has not been adopted nor risk factors identifying patients at risk for recurrence defined. To address these issues, this study evaluated the influence of various clinicopathologic variables on overall and disease-free survival. In an univariate analysis of overall survival involving 191 patients, the Cox proportional hazards model identified four factors that were associated with a significantly better outcome: complete resection without tumor rupture (p less than 0.001), localized lesions (p less than 0.001), low grade of tumor (p = 0.02), and tumors smaller than 5 cm (p = 0.03). When interactive effects of these factors were taken into account, however, type of resection of the tumor was selected as the only significant prognostic factor in a multivariate analysis. Complete resection without tumor rupture improved overall survival of patients with localized disease (median, 46 months) as well as those with contiguous organ invasion (median, 36 months) or peritoneal implants (median, 36 months). In contrast, patients with incomplete resections survived for a median of 21 months. Patients with tumor rupture, despite removal of all gross disease, behaved similarly to those with incomplete resections; median survival was only 17 months. For disease-free survival, important determinants selected from a multivariate analysis were tumor rupture (p = 0.002), contiguous organ invasion (p = 0.02) and high tumor grade (p = 0.02). A staging classification incorporating these prognostic factors of significance was evaluated using a TGM system: T1 (less than 5 cm), T2 (greater than or equal to 5 cm), T3 (contiguous organ invasion or peritoneal implants), T4 (tumor rupture); G: G1 (low grade), G2 (high grade); M: M0 (no metastases), M1 (metastases present). The corresponding 5-year overall survivals for stages I, II, III, IVA, and IVB were 75%, 52%, 28%, 12%, and 7%. Disease-free survival at 2 years after surgery was 89%, 57%, and 47% for stages I, II, and III, respectively. In conclusion, surgery remains the primary modality of treatment for patients with gastrointestinal leiomyosarcomas, and complete resection of all disease without tumor rupture, even of locally advanced disease, improves overall and disease-free survival. A staging classification appears feasible and is recommended to determine outcome in patients with leiomyosarcomas arising from the gastrointestinal tract.

Stage and histological grade of gastrointestinal stromal tumors based on a new approach are strongly associated with clinical behaviors

“…There is a strong need for a practical and reliable classification system that can be used to predict the clinical course of GIST patients and facilitate the design of treatment regimen. On the basis of previous investigations and our preliminary work, [10][11][12][13][14][15][16][17][18] we collected the pathological and clinical data of a large number of GIST patients and assessed a simple and new grading and staging system. Patients from multiple hospitals were analyzed because it is expected to be more likely free of selection bias, which could occur in different hospitals or treatment trials.…”

“…This is the first time that the degree of malignancy was demonstrated by the number of the predictive parameters of malignancy. Previous studies have demonstrated that the adverse outcome of GISTs correlates with the increase in the tumor size, 12,16,25,[50][51][52][53] mitotic rate, 20,25,51,52,54 cellularity 51,52,55 and nuclear atypia. 16 In addition, tumor site 23,56,57 from the upper to lower GI tract seemingly had an effect on the outcome too.…”

“…Many investigators made efforts to grade [10][11][12][13][14][15] and/or stage GISTs. 11,[16][17][18] On the basis of these previous reports and our preliminary study, we selected 12 parameters that not only had predictive value for malignancy, but also had value to stage and grade GISTs effectively. 19 We introduced a new and simple method based on these parameters for the staging and grading of GISTs.…”

Laparoscopic wedge resection of a gastric leiomyoma

“…7 Gastric resection without lymph node dissection in the treatment of malignant neoplasm (such as leiomyosarcoma) may be controversial although studies have demonstrated no benefit from the addition of systemic lymph node dissection or more extensive resection in the treatment of leiomyosarcoma. 8,9 These results are important when considering the laparoscopic technique for any gastric stromal tumor resection because often the diagnosis of leiomyosarcoma versus leiomyoma may not be evident until after resection. In fact, biopsies from endoscopy yield the diagnosis in less than 60% of the time.…”

“…10,11 Although some authors feel that more extensive resections may be necessary for high-grade leiomyosarcoma, 12 others believe that a wedge resection is sufficient for leiomyosarcomas. 8,9 Four major laparoscopic methods have been described for the resection of gastric leiomyoma. The choice of technique should be based both on size and location of the lesion.…”