Bronchoscopic biopsy was non-diagnostic, and the patient underwent VATS biopsy.
MACROSCOPIC DESCRIPTION:
Right upper lobe wedge resection: A wedge of lung measuring 30 x 8 x 10mm. On sectioning, the lung parenchyma has a dark grey and cream nodular appearance.
MICROSCOPIC DESCRIPTION:
Sections of the lung show variably dilated alveolar spaces, most of which appear rather cellular. There is a polymorphic infiltrate of cells which include eosinophils, lymphocytes, histiocytes and groups of cells with moderate amounts of pale cytoplasm and medium sized, round, oval or indented nuclei and delicate chromatin. Some of the nuclei have distinct grooves. There are occasional multinucleated cells included. These cells show strong staining with CD1a and S-100 and are negative with CD68. The CD68 stain however marks the alveolar macrophages. The features are consistent with Langerhans cell histiocytosis. There are no granulomas. There is no neoplasia in the sections examined.
DIAGNOSIS: Features consistent with Langerhans cell histiocytosis.