Synchronous multiple carcinoma with small intestine and pulmonary neuroendocrine involvement

RATIONALE In clinical work, neuroendocrine synchronous multiplicity carcinoma was relatively rare. Most were confirmed by the pathological diagnosis of a certain part of the body combined with the imaging of the whole body, while cases that had both pathological and immunohistochemistry diagnosis were few. PATIENT CONCERNS A patient who presented with abdominal pain visited our hospital, and was diagnosed with lesions in both the small intestine and lung. DIAGNOSES Both were considered primary tumors by imaging, and diagnosed as neuroendocrine carcinomas by pathology. INTERVENTIONS The intestinal lesion was surgically resected, and the lung tumor treated by chemoradiotherapy. OUTCOMES The survival time of this patient exceeded 24 months. LESSONS The diagnosis relied on clinical, imaging, pathological, and immunohistochemical features, which confirmed a synchronous multiple carcinoma. Treatment was based on the pathological types. Through this case report, the clinical and pathological data of neuroendocrine synchronous multiplicity carcinoma could be enriched.