A Case Report of Rare Synchronous Esophageal Malignancies With Dissimilar Histology: Squamous Cell Carcinoma and Small Cell Carcinoma

The presence of synchronous primary malignancies is a rare phenomenon reported in the literature. Most synchronous malignancies reported include carcinomas and adenocarcinomas of the gastrointestinal tract, head and neck cancers, thyroid and breast cancers. Among the neuroendocrine tumors, carcinoid tumors in the duodenum or the esophagus are most commonly reported with other primary malignancies. We report the case of a 56-year-old male with tobacco use disorder, presenting with dysphagia and weight loss for six months, who was thought to have multicentric squamous cell carcinoma of the esophagus. In actuality, he was diagnosed with synchronous metastatic neuroendocrine tumor (NET) favoring small cell carcinoma and squamous cell carcinoma of the esophagus. The patient responded well to minimally invasive thoracoscopic esophagectomy with regional lymphadenectomy followed by chemotherapy and radiation therapy. We have not been able to find a literature referencing the presence of synchronous small cell carcinoma and squamous cell carcinoma of the esophagus, making our case unique.