Male, 34 years old, smoker of 15 cigarettes a day, with a history of peptic oesophagitis, hiatus hernia and non-allergic bronchial asthma. Diabetic father. He presented with severe abdominal pain in the left flank, pasty stools and increased abdominal sounds, and was assessed in primary care, initially interpreting the symptoms as possible acute gastroenteritis. Examination revealed slight pain on palpation in the left abdomen and a slight increase in peristalsis. Given the persistence of the pain, various complementary tests were requested.
While awaiting further assessment, 10 days after his visit to primary care, he came to the hospital emergency department for a new episode of intense abdominal pain in the left flank, this time accompanied by diaphoresis, nervousness and skin pallor. He was assessed three times in the emergency department, diagnosed and treated as renal colic. Blood pressure: 136/95 mm Hg; heart rate: 89 l/min; temperature: 37.7o; sweating. Abdominal examination revealed left flank pain with positive left renal suction. The rest of the physical examination was normal. Chest and abdominal X-rays were normal. There was minimal leukocytosis (10,500), mild hyponatraemia and CRP=13.
As there was no clinical improvement with symptomatic treatment, an abdomino-pelvic ultrasound scan was performed showing a tumour in the left adrenal gland. Following this result, a CT scan was requested, showing a mass of 6.5 cm in diameter depending on the left adrenal gland, which led to a differential diagnosis of pheochromocytoma or adrenal carcinoma.

Following this result, the patient was referred to the Urology Department and from there to the Internal Medicine Department for a functional study in an attempt to rule out pheochromocytoma. The determination of urinary metanephrines and catecholamines showed a reading of more than five times the normal value for total urinary metanephrines and urinary free catecholamines. A diagnosis of a functioning left adrenal mass is made, with marked elevation of metanephrines due to probable pheochromocytoma. Once the diagnosis of pheochromocytoma was established, it was decided to perform a laparoscopic total left adrenalectomy after blockade with dosazoxin 4 mg/day. The anatomopathological analysis of the surgical findings showed that it was a malignant pheochromocytoma of 130 g and 6 x 6 cm, with extensive necrosis, marked cellular pleomorphism, abundant atypical mitoses (<50 x 10 cga), capsular invasion and a tumour thrombus in a large-calibre vein (the clamped vein), with no extra-adrenal extension. The trans-operative period passed without complications. During the whole process the patient presents normal blood pressure figures with good general condition, and no treatment is carried out.