What happened, in summary

A non-smoking woman in her 50s had undergone thoracoscopic surgery and mediastinal lymph-node dissection 7 years earlier for a 1.9 cm lung adenocarcinoma. That earlier cancer had been Stage IA2, pT1aN0M0, and she had remained under regular CT follow-up.

During surveillance, several nodules appeared in both lungs. Because of her previous lung cancer, the main concern was metastatic recurrence. The nodules had imaging features that could easily be mistaken for spread from the earlier adenocarcinoma.

She underwent video-assisted wedge resection of a nodule in the right upper lobe so a definite diagnosis could be made. Pathology and immunohistochemistry showed a different rare tumor: pulmonary epithelioid hemangioendothelioma. The cells were positive for vascular markers including CD31, ERF, and TFE3. This established a vascular lung tumor rather than recurrent lung adenocarcinoma.

No chemotherapy was given. The remaining nodules were followed with serial CT scans. At 1 year after the diagnostic surgery, the residual pulmonary nodules had not increased in size and no distant metastases had appeared. She remained under observation with stable multifocal lung disease. Pulmonary epithelioid hemangioendothelioma can grow slowly, so observation was reasonable while she had no symptoms and the nodules stayed unchanged. The diagnosis also prevented incorrect treatment for recurrent adenocarcinoma. Her earlier lung cancer and the new vascular tumor were followed as separate diseases. She continued regular follow-up at the same hospital, using CT surveillance to track the residual nodules rather than starting immediate systemic treatment.