TTF1 and lung adenocarcinoma: An EBUS scan revealed non-necrotizing granuloma in a COPD patient, who was reviewed for sarcoidosis treatment. A nodule biopsy was also performed on the patient to rule out cancer sarcoid syndrome. A poorly differentiated adenocarcinoma of the lung was reported that was positive for GATA3, P63, CK7, and TTF-1. The patient underwent surgical intervention, and no signs or symptoms of systemic sarcoidosis were documented. According to the study, identifying cancer earlier improves the patient's outcome and prognosis.