Primary localized rectal/pararectal gastrointestinal stromal tumors: results of surgical and multimodal therapy from the French Sarcoma group

Abstract

BackgroundRectal and pararectal gastrointestinal stromal tumors (GISTs) are rare. The optimal management strategy for primary localized GISTs remains poorly defined.MethodsWe conducted a retrospective analysis of 41 patients with localized rectal or pararectal GISTs treated between 1991 and 2011 in 13 French Sarcoma Group centers.ResultsOf 12 patients who received preoperative imatinib therapy for a median duration of 7 (2-12) months, 8 experienced a partial response, 3 had stable disease, and 1 had a complete response. Thirty and 11 patients underwent function-sparing conservative surgery and abdominoperineal resection, respectively. Tumor resections were mostly R0 and R1 in 35 patients. Tumor rupture occurred in 12 patients. Eleven patients received postoperative imatinib with a median follow-up of 59 (2.4-186) months. The median time to disease relapse was 36 (9.8-62) months. The 5-year overall survival rate was 86.5%. Twenty patients developed local recurrence after surgery alone, two developed recurrence after resection combined with preoperative and/or postoperative imatinib, and eight developed metastases. In univariate analysis, the mitotic index (≤5) and tumor size (≤5 cm) were associated with a significantly decreased risk of local relapse. Perioperative imatinib was associated with a significantly reduced risk of overall relapse and local relapse.ConclusionsPerioperative imatinib therapy was associated with improved disease-free survival. Preoperative imatinib was effective. Tumor shrinkage has a clear benefit for local excision in terms of feasibility and function preservation. Given the complexity of rectal GISTs, referral of patients with this rare disease to expert centers to undergo a multidisciplinary approach is recommended.

Rectal Gastrointestinal Stromal Tumor (GIST) in the Era of Imatinib: Organ Preservation and Improved Oncologic Outcome

“…Our report is distinct from other modern series 13–15,18–20 . First, our data represent the largest single-institution experience, coming from a prospectively maintained database with mature follow-up, as opposed to multiple institutions where treatment strategies and follow-up patterns vary.…”

“…Our series spans the historical and imatinib eras, while some publications were only in the recent era 14,15,18,19 . Some included patients who did not receive imatinib either due to availability (pre-imatinib) or because it was not felt to be indicated clinically; often these patients were analyzed as one group or without clear designation 13,18,20 . Finally, we were able to classify the Miettinen risk groups for 96% of our patients, while in many other reports the risk status was often unclear or there was no comparison group.…”

Characteristics and prognosis of rectal gastrointestinal stromal tumors: an analysis of registry data

“…In fact, nine patients in our series underwent local excisions and our data showed a high rate of R0 resection achieved in these patients. On the other hand, according to another report [17], resections with a clear margin were less commonly achieved by anal-sparing surgery than by abdominoperineal resection.…”

“…Thus, we think that imatinib treatment should be given for at least 2 months or more as neoadjuvant therapy. Given the lack of evidence concerning the role of neoadjuvant and adjuvant treatments, some trials have been conducted to show the potential survival benefit or feasibility of sphincter-preserving surgery [9,10,17,[19][20][21][22]. Thus, preoperative imatinib is a reasonable option for patients with locally advanced rectal GIST occupying the pelvic space, who require multivisceral resection to achieve clear surgical margins.…”

Gastrointestinal Stromal Tumors

“…Thus, if a primary resection does not seem possible, our standard procedure is neoadjuvant treatment [6,7]. To identify any non-responder, we closely monitor the evolution clinically and radiologically, sometimes including PET, particularly for low-seated lesions.…”