University of Miami Miller School of Medicine Hallandale Beach, FL
Introduction: A fecalith is a mass of accumulated hardened fecal matter that usually arises in the colon, most commonly the sigmoid and the rectum. Very rarely does a fecalith appear in the small intestine. GISTs are rare soft tissue sarcomas that can occur anywhere along the gastrointestinal tract. It is documented in the literature that fecaliths can mimic tumors. However, this report is the first documented case of a fecalith obscuring the presentation of a GIST, and even more unique given it was found in the cecum. Thus, the seemingly benign presentation of a fecalith may be a more concerning manifestation and consequently prompt further workup.
Case Description/Methods: A 58-year-old Hispanic male with a past medical history of HIV and melanoma, presented to the ED with a week of right lower quadrant abdominal pain. Physical exam was remarkable for severe pain on deep palpation of the right lower quadrant. Laboratory studies and vitals were normal and tumor markers, carcinoembryonic antigen, CA 19-9, and CA-125, were negative. A CT abdomen/pelvis scan was significant for colonic wall thickening, a “mass-like structure” in the cecum extending to the level of the ileocecal valve and enlarged peri-colonic lymph nodes. A colonoscopy was performed that showed a large fecalith in the cecum. After a failed attempt at removing the fecalith via colonoscopy, the patient underwent laparoscopic hand-assisted right colectomy the following Monday. The surgery was successful, and the patient’s postoperative course was unremarkable. He was discharged on postoperative day seven.
The pathology report indicated that the mass-like fecalith structure was a low-grade multifocal GIST of spindle cell type involving 5 cm of the bowel wall, 2 mitoses per 5mm2, Ki 67 was less than 5%, pT2N0. A GIST neotype profile indicated the tumor was of the KIT D820G (Exon 17) missense mutation variant. It was decided the patient would benefit from oncology follow-up for adjuvant imatinib as well as follow up CT scans once every 3 months.
Discussion: This case report depicts an unusual presentation of a fecalith and GIST in the cecum. While the patient underwent a thorough workup, the true etiology of his abdominal pain was not realized until surgery. This was likely due to the large fecalith’s atypical location that obscured the presentation of the GIST. This case report is of clinical relevance because it depicts a diverse way that GISTs may present, and can hopefully expedite the recognition and appropriate treatment of similar cases.
