P1963 - An Extremely Rare Case of the Colorectal Gastrointestinal Stromal Tumor Metastasized to Brain Presenting as Intractable Nausea and Unintentional Weight Loss

Shreel H. Patel, MD¹, Nirav B. Patel, MS², Dhruvkumar Patel, MBBS³, Hareesh Gundlapalli, MD⁴, Kashif Ali, MD⁵, Oliverio Abarca Guzman, MD⁶, Sahir Bhatti, MD⁶, Roy Subhash Kondapavuluru, MD¹, Eunbee Cho, MD⁶, Jawairia Memon, MD⁷, Fatimah Bello, MD¹, Valeska Balderas, MD^8
1University of Texas Rio Grande Valley - Knapp Medical Center, Weslaco, TX; ²GCS Medical College, Hospital and Research Centre, Weslaco, TX; ³LSU Health Science Center, Shreveport, LA; ⁴University of New Mexico, San Antonio, TX; ⁵University of Texas Rio Grande Valley, Edinburg, TX; ⁶UTRGV-Knapp Medical Center, Weslaco, TX; ⁷UTHSCSA, San Antonio, TX; ⁸Texas Gastroenterology Institute, McAllen, TX

Introduction: Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms of the GI tract. GISTs that arise from the bowel wall typically present as sub-epithelial neoplasms in the stomach and small intestine, however, they can also arise in any portion of the GI tract and, also on the omentum, mesentery, and peritoneum. Most GISTs harbor characteristic mutations in KIT or platelet-derived growth factor receptor alpha (PDGFRA). Most commonly found in the stomach, jejunum and ileum. Very rarely it is seen in the colon and those with colon involvement or rectum could present with constipation, and bowel obstruction. Therefore, we present a rare case of the colorectal GIST metastasized to lungs and brain.

Case Description/Methods: A 57-year-old man with no medical history presented to ED with chief complaint of severe nausea, vomiting and constipation from past 20 days associated with 50 pounds of unintentional weight loss in last 3 months. He denied any melena, hematemesis, hematochezia, hematuria, dysphagia, chest pain, near syncope, or any family history of malignancy. He did not smoke, drink alcohol or use any recreational drugs. CT Abdomen Pelvis was done which showed large sigmoid colonic centrally necrotic mass suggestive of aggressive neoplasm with multiple pulmonary metastases. The patient underwent manual dis-impaction and NG tube was placed to alleviate the symptoms. Colonoscopy was done but did not yield much as bowel prep was inadequate. CT guided biopsy of lung nodules was done, meanwhile the patient continued to have nausea and vomiting, hence, CT head was ordered, which showed multiple cavitary lesions in brain parenchyma. Simultaneously, the biopsy from lung nodule, came out to be positive for the spindle cell neoplasm, which metastasized from the sigmoid colonic mass which was the primary site of malignancy. Hence the diagnosis of the Gastrointestinal Stromal Tumor (GIST) of Colon was made, which is very rare. The patient was eventually referred to the neurosurgeon and oncologist for the further management, but patient decided to go for the palliative care and aggressive pain regimen was started.

Discussion: Colorectal GISTs are extremely rare and comprise approximately 0.1 percent of all colorectal tumors. Sometimes when the mass is large, not amenable to resection, biopsy can be taken from the distant sites. The main treatment is imatinib in GIST which have metastasized. Hence, knowing that what are the rare presentations of GIST can help to expedite the diagnosis and treatment.



Disclosures:


Shreel H. Patel, MD¹, Nirav B. Patel, MS², Dhruvkumar Patel, MBBS³, Hareesh Gundlapalli, MD⁴, Kashif Ali, MD⁵, Oliverio Abarca Guzman, MD⁶, Sahir Bhatti, MD⁶, Roy Subhash Kondapavuluru, MD¹, Eunbee Cho, MD⁶, Jawairia Memon, MD⁷, Fatimah Bello, MD¹, Valeska Balderas, MD⁸. P1963 - An Extremely Rare Case of the Colorectal Gastrointestinal Stromal Tumor Metastasized to Brain Presenting as Intractable Nausea and Unintentional Weight Loss, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.