Solitary adrenal metastasis from advanced gastric cancer invading duodenal bulb with situs inversus totalis: A case report

RATIONALE: Situs invsersus totalis (SIT) is a rare anomaly featured by complete inversion of abdominal and thoracic organs. Adrenal metastasis is often encountered as part of advanced systemic dissemination, which is usually unresectable. Few published cases reported the adrenal metastasis from gastric cancer with SIT and the treatment of gastrectomy combined with adrenalectomy, especially with intraoperative radiotherapy (IORT). PATIENT CONCERNS: A 61-year-old SIT man found a mass on the right clavicle and the biopsy revealed a metastatic cancer. Around 14 years ago, he had a rectal cancer resection surgery and no sign of occurrence. Five months later, the patient had a pain in his right low abdomen and abdominal CT found a right adrenal mass. DIAGNOSES: Gastroscopy and the pathology revealed the gastric antrum cancer invading the duodenal bulb. Abdominal enhanced CT suspected the adrenal mass as a hematoma, but positron emission tomography computed tomography suspected it as the metastases of gastric cancer which is consistent with the pathology results. Finally, the SIT patient was diagnosed with primary gastric cancer invading duodenal bulb with solitary right adrenal metastasis. INTERVENTIONS: The patient was treated with curative distal gastrectomy and Billroth-II anastomosis with D2 lymphadenectomy. A total 18 Gy intraoperative radiotherapy (IORT) using low energy x-rays by Intrabeam were given after resection. OUTCOMES: The patient had liver metastasis in the seventh month after surgery but there is no sign of local recurrence until now. LESSONS: Gastric cancer with adrenal metastasis, especially with SIT is rare and intractable. The result suggested that active surgical treatment for resectable gastric cancer and solitary adrenal metastatic tumor, especially in combination with IORT may be an option in controlling local relapse and prolonging survival in selected patients.