Oncological Results for the Surgical Treatment of Rectal Gastrointestinal Stromal Tumor

Purpose. Primary gastrointestinal stromal tumor (GIST) of the rectum is rare and its clinico-pathology is not well understood. This study investigated the clinical characteristic of rectal GIST treated in a single institute. Methods. From January 1990 to December 2007, medical records in our institute were reviewed and patients who underwent surgery for rectal GIST were identified. Their demographic features, tumor size, tumor location, clinical symptoms, operation methods, adjuvant treatment, recurrence, and survival were investigated and analyzed. Results. Of the ten rectal GIST cases identified, nine were males. The median age at the time of diagnosis was 57 years (range: 38-82) and the median survival time was 23 months (range from 4 to 107 months). The major symptoms as an initial presentation were tenesmus, lower GI bleeding and palpable abdominal mass. The mean size of tumor was 9.3cm (range: 3.2 to 15cm). The overall 5-year survival rate was 38.1% and 5-year disease free survival rate in patients of complete resection was 21.4%. The five-year survival rate is 0% in non-curative resection patients and 42.9% in curative resection patient (p=0.24). The five years survival rate is 0% in patients with tumor≥10cm and 60% in patients with tumor＜10cm. (p=0.006) Conclusion. The most common symptoms of rectal GIST are tenesmus and lower GI bleeding, which are similar to those of other kinds of rectal tumors. The tumor size≥10cm is a risk factor of prognosis in rectal GIST. The appropriate treatment for rectal GIST is complete resection without residual tumors, with complete removal of metastases even in patients with recurrence. Future studies should focus on neo-adjuvant treatment strategies.