Abstract
Background. Adult-onset tuberculous lymphadenitis is a rare disease that, in many cases, is diagnosed during examinations of and treatment for primary lung cancer. Case. A 51-year-old male with contralateral second lung cancer and mediastinal tuberculous lymphadenitis was treated at our institute. He had received induction chemoradiotherapy followed by right upper lobectomy with chest wall resection for a right lung adenocarcinoma. Four years after treatment for the initial lung cancer, 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) revealed abnormal accumulation in the apex of the left lung and left lower paratracheal lymph node. The preoperative diagnosis was contralateral pulmonary metastasis and mediastinal lymph node recurrence of the initial lung cancer or second primary lung cancer with mediastinal lymph node metastasis. Left upper division segmentectomy and mediastinal lymph node dissection were performed. A histological examination of the pulmonary tumor revealed large-cell lung carcinoma. The mediastinal lymph node contained an epithelioid granuloma with caseous necrosis. There were Langhans giant cells observed in the granulation tissue. Therefore, mediastinal tuberculous lymphadenitis was diagnosed, and tuberculosis treatment was administered postoperatively. Conclusions. Tuberculous lymphadenitis is recognized to be a mediastinal disease associated with abnormal accumulation on FDG-PET scanning. In this case, an aggressive approach led to the correct diagnosis, allowing appropriate treatment to be administered.
