A 50-year-old man with a history of arterial hypertension under treatment and appendicectomy at the age of 25, consulted for epigastralgia, melena and asthenia for the last fifteen days. He did not report dysphagia, heartburn or altered bowel habits.
The physical examination was normal, there were no palpable masses or visceromegaly in the abdomen, and there were no signs of malnutrition.
Laboratory tests showed the presence of hypochromic microcytic anaemia with Hgb of 10g/dl and Ht of 33%. Chest and abdominal X-rays showed no alterations of interest. Upper endoscopy showed a normal oesophagus, a gastric cavity without haematic debris with normal mucosa and erosions on an oedematous mucosa in the duodenal bulb; biopsies were taken from the antrum and body, and the biopsies were reported as chronic gastritis without activity, and helicobacter pylori was not detected. In the abdominal ultrasound, the liver, gall bladder and pancreas were normal.
With the diagnosis of upper gastrointestinal haemorrhage due to erosive duodenitis and anaemia secondary to digestive losses, he was discharged for outpatient follow-up with treatment with antisecretory drugs. The patient was readmitted three weeks later for a new episode of melena. A new upper gastrointestinal endoscopy was performed, revealing a normal oesophagus, gastric cavity mucosa and duodenal bulb, with isolated haematic remains at the level of the second portion of the duodenum, It was therefore decided to perform a pulsation enteroscopy, revealing a friable, ulcerated tumour in the proximal jejunum that partially stenosed the jejunal lumen and did not allow the endoscope to pass, but did allow multiple biopsies to be taken at the edges of the tumour. An intestinal transit was carried out in which a short stenosis was observed in the proximal jejunum, which allowed the passage of contrast material.

The extension study was completed with an abdominal CT scan, which revealed the presence of a mass in the proximal jejunum with no significant locoregional or retroperitoneal adenopathies, no focal hepatic lesions suggestive of metastasis, and no other radiological alterations that could be assessed. With the diagnosis of low-grade leiomyosarcoma of the small intestine and after ruling out distant tumour extension or local invasion in the imaging studies, surgical treatment was decided with resection of the tumour and subsequent duodeno-jejunal anastomosis. The patient's evolution was satisfactory and did not require adjuvant treatment.