[Gastrointestinal stromal tumors. Report of two cases]

We undertook this study to describe two cases of intestinal gistoma histologically and immunochemically proven.

The study took place at a third level health care hospital in Mexico. Case 1. We report the case of a 39-year-old female with 4 years evolution of lower abdominal pain and with a 16-cm tumoral mass. The patient reported a 28-kg weight loss during the previous 6 weeks. Ultrasound revealed a left adnexal mass (12 x 17 x 15 cm) and CA125 tumor marker value of 4 ng/ml. Laparotomy identified a 15-cm intestinal mass with metastasis to mesentery, diaphragm and bladder. Palliative resection was performed of the small bowel, intestinal mass and termino-terminal anastomosis. The patient was referred to the Medical Oncology Department for adjuvant treatment. Case 2. We report the case of a 37-year-old female with digestive hemorrhage (hematoquezy) during a period of 3 years who needed a blood transfusion on several occasions. The most recent transfusion was 2 days prior to her hospitalization. Physical examination did not reveal any abnormalities; hemoglobin was 8.3 g/dl, platelets 135,000/dl and white blood cells 8.8/dl. Patient had a normal panendoscopy and colonoscopy. Abdominopelvic ultrasound revealed polycystic ovaries, technetium-99 nuclear scan revealed the presence and persistence of Meckel diverticulum. Laparotomy showed intestinal mass of 5 x 5 cm, 70 cm from Treitz angle. We used a wide intestinal resection, proximal and distal from the mass and termino-terminal anastomosis. Histochemical study was CD34 positive. The patient was asymptomatic 3 months postoperatively.

Gistomas are tumors of the gastrointestinal tract that are difficult to diagnosis because they are located in the submucosa. Treatment for primary tumor is surgical. Treatment for recurrent or metastatic GIST is imatinib or, if the patient is allergic to imatinib, another new tyrosine kinase inhibitor such as subitinib may be used. Definitive diagnosis is made by immunohistochemistry against CD117, and CD34, in the same manner as our cases.