A 32 year-old man referred to the gastroenterology clinic, complaining from dyspepsia and post-prandial discomfort for 3 weeks. He also mentioned rectorrhagia within the last 10 days. The patient complained of malaise. He did not mention nausea, vomiting, abdominal pain, any changes in bowel habits or weight loss. In his past medical history, he did not mention symptoms of a minor depression. He didn’t take any medications. He was not a smoker or an alcohol consumer.

He Looked I11 and His Vital Signs Were as Below
Blood pressure: 110/60 mmHg, pulse rate: 79 per minute, respiratory rate: 16 per minute and body temperature from oral root: 37.4°C.
During physical examination, his abdomen was not distended and was soft with no tenderness in palpation. The rest of examinations were unremarkable.
The patient underwent an upper GI endoscopy, which revealed a 2×2cm submucosal lesion (Figure 1) at the gastric body, and Endoscopic Ultrasound (EUS) was recommended. The EUS revealed a 22×20 mm hypoechoic lesion in the midportion of lesser curvature that originates from the muscularis propria layer with some cystic degeneration. No regional lymphadenopathy was detected. The pancreas and biliary systems looked normal (Figure 2). With a suspension of stromal tumor, surgery was recommended.

Colonoscopy up to the descending colon demonstrated exudate, bleeding and mucosal erythema in the rectum, sigmoid and descending colon (Figure 3). A biopsy was taken and a pathological study revealed ulcerative colitis (Figure 4).
An abdominal spiral CT scan with triphasic protocol of the liver and oral and IV contrast was performed and no apparent abnormality was detected.
Then, the patient underwent surgery, and a pathological study of the gastric lesion revealed a well-circumscribed intramural mass composed of sheets of spindle cells with minimal pleomorphism. The mitotic activity was 1-2 mitoses per 50 high-power fields (1- 2/50 HPF). The final diagnosis of the lesion was a low grade, spindle type GIST with very low risk of progressive disease, and pathological tumor-node-metastasis (pTNM) staging was pT2 (the tumor has grown into the muscularis propria, the muscle layer of the stomach), NX (Regional lymph nodes cannot be evaluated) and MX (Distant metastasis cannot be evaluated) (Figure 5).
Treatment was initiated with oral Mesalazine (5-aminosalicylic acid) and Asacol enema. Since the tumor was classified as low risk, no systemic chemotherapy was given. As the abdominal and pelvic CT showed no metastasis, a complete surgical resection of the tumor was performed and due to low Ki67 levels and no metastasis, Imatinib was not prescribed. In a 6-month follow up, the patient had no problem.

Figure 3. Endosonography of the patient


Figure 4. A: Well-circumscribed intramural mass. B: Architectural crypt distortion, cryptitis and crypt abscess


Figure 5. Tumor cells are diffusely positive for C-kit and CD 34, partially positive for SMA and are negative for S100

Discussion

An important issue in the management of IBD is the risk of malignancies, which is mostly reported in patients receiving prolonged immunosuppressive therapy or biological agents and are rare at the initiation of the disease (7). A prolonged inflammatory state is a risk factor for the progression of malignant lesions too. The most common cancer in IBD patients is adenocarcinoma. (8, 9).
GISTs, are among rare tumors in IBD patients, and there are few reports of such cases (6, 10). The most common site of involvement is the stomach, following by the jejunum, ileum, duodenum and colon. Previous studies demonstrated that the risk of the incidence of GIST is not related to IBD activity; so, in IBD patients who are symptomatic and have no evidence of disease reactivation, GIST should be considered in the differential diagnosis (11).
The treatment of choice for GIST is surgical resection. The tumor should not be opened because of the risk of peritoneal dissemination. Lymph node involvement is not common.
In our patient, endoscopic findings, as well as clinical evaluations, confirmed the diagnosis of UC, and GIST had no symptoms. Most GIST cases with IBD have a long history of IBD prior to the development of malignancy (12, 13).
In managing of IBD patients, investigating for probable malignancies is a key point for early diagnosis and improve the outcomes of the disease (14). The coincidence of UC and GIST is extremely rare. Grieco et al. reported a 57-year-old woman affected by UC in remission, whose abdominal CT scan revealed GIST in the upper left pelvic cavity (15). So, in cases with IBD diagnosis, GIST should be considered in further evaluation and differential diagnosis.

 

Acknowledgements

The authors thank all those who helped them writing this paper.

 

Conflicts of Interest

Authors declared no conflict of interests.