2021 Volume 61 Issue 1 Pages 35-39
Background. There have been reports of small-cell lung cancer found in cases of hilar and mediastinal lymphadenopathy with no primary lesion. We experienced a case of T0N1M0 small-cell lung cancer. Case. A 61-year-old man had a history of endoscopic submucosal dissection (ESD) for middle esophageal cancer 8 years ago and for gastric cancer 5 years ago. The gastric cancer had been completely resected endoscopically according to the pathology. However, with regard to the esophageal cancer, he was requested to be followed up, although additional excision was advised due to the depth to the wall. The left main bronchial lymph node was found to be swollen at follow-up. This node was located near the esophageal cancer that had been treated with ESD, which initially suggested esophageal cancer metastasis. As no other lesions were found, including in the esophagus after ESD, the node was resected for a diagnosis. The left main bronchial lymph node was removed thoracoscopically. The pathological findings resulted in a diagnosis of lymph node metastasis of small-cell lung cancer. There was no apparent primary lesion on image findings or endoscopically, so it was assumed to be a lung primary tumor and judged to be T0N1M0 small-cell lung cancer. Conclusion. We experienced a case of small-cell lung cancer of unknown primary origin with hilar lymphadenopathy. We believe that additional treatment including chemotherapy will be necessary in the future.