Primary isolated nodular pulmonary amyloidosis is a rare condition of unknown aetiology. The disease runs a benign course but offers a diagnostic problem since it often simulates neoplasm. A case is reported in which the initial diagnosis of a suspected squamous cell carcinoma was made on the basis of material obtained by transthoracic needle biopsy. Lobectomy was performed and the histopathological and histochemical examinations gave the diagnosis of amyloidosis. Re‐examination of the aspiration biopsy material demonstrated the possibilities of making a cytological diagnosis of amyloidosi