Perforation of small intestine secondary to metastatic lung adenocarcinoma: A case report

RATIONALE: About 50% of patients with a diagnosis of nonsmall cell lung carcinoma exhibit metastatic disease at the time of diagnosis. The preferential sites of extrapulmonary spread are the lymph nodes, liver, brain, adrenal glands, and bones; gastrointestinal tract perforation secondary to metastatic lung cancer is extremely rare. PATIENT CONCERNS: A 60-year-old male nonsmoker patient presented with a 20-day history of facial, neck, and right upper limb edema. Physical examination revealed a 3.5 cm mass in his right chest. Computed tomography (CT) revealed a 4 cm mass near the right lung hilum. DIAGNOSIS: Biopsy of the right chest wall mass revealed low differentiated lung adenocarcinoma. Additionally, retroperitoneal lymphadenopathy, pericardial effusion, metastases in the mediastinum, bilateral adrenal gland, and right thoracic wall nodule, as well as multiple bone metastases were also found. INTERVENTIONS: Since the patient was diagnosed with multiple metastatic lung cancer, chemotherapy was started. One week after chemotherapy, he experienced a sudden acute abdominal pain. Abdominal CT examination indicated the possibility of intestinal perforation. Hence, the patient underwent an emergency operation. During the surgical procedure, 2 perforations of size 1×1 cm(2) were discovered at 110 cm and 140 cm of the jejunum from Treitz's ligament. Then, an intestinal resection and end-to-end anastomosis were performed. The pathological diagnosis of the resected specimen revealed that it was a metastatic lung adenocarcinoma of small intestine. OUTCOMES: The patient died 10 days after operation and 19 days following the cancer diagnosis due to septic shock. LESSONS: Gastrointestinal tract metastasis from the lung is uncommon, but the survival rate is extremely low; therefore, it should be considered as a possibility in patients who present with any of the gastrointestinal symptoms.