Angiofollicular lymph node hyperplasia of the lung simulating carcinoma: pseudolymphoma with inflammatory changes

Angiofollicular lymph node hyperplasia of the lung developed in a 45-year-old man who was a heavy smoker. Slow growth of the lesion 3 years after biopsy and the finding of atypical cells in the sputum and bronchial washings strongly suggested a malignant lesion. There were no systemic manifestations other than dyspnea, which may have been related to allergy. The lesion was angiofollicular lymph node hyperplasia of the hyaline-vascular type. Invasion by lymphoid cells of both blood vessels and bronchioles suggested that the pathogenesis was probably infectious or inflammatory; also, the nature of the infiltrate indicated an immune mechanism. The course of the disease, as in other cases reported, has been benign, though a patchy density has developed in contralateral lung 4 years after lobectomy.