Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor of GI (gastrointestinal) tract. It arises from the interstitial cells of cajal.1 It can arise from any site of the GI tract. The stomach is the most common site; however, it can arise from any site of GI tract and rarely involves the anorectal region.2 The incidence of anorectal GIST is 0.018 per 100,000; this comprises about 2.8% of all GISTs.3 GIST at other locations had worse prognosis compared to that in the stomach.4 Surgery is the mainstay of treatment as it is resistant to conventional chemotherapy. However, tyrosine kinase inhibitors such as imatinib mesylate can be used in a neoadjuvant or adjuvant setting.5 Margin-free resection is the goal. Anatomical factors in the pelvic area lead to recurrence. There are few case reports and small series in the literature regarding the successful use of imatinib in the neoadjuvant setting followed by surgery. Here we are reporting a case of malignant GIST of lower rectum who was managed with abdominoperineal resection following neoadjuvant imatinib therapy and achieved a recurrence-free survival after 4 years of follow-up.
https://www.jmedsciences.com/doi/JMEDS/pdf/10.5005/jp-journals-10045-00135