of solitary pulmonary nodules which may also be caused by malignancy, metastasis, granuloma or other benign tumours. [3][4][5] Most of these lesions are asymptomatic, except when they are endobronchial in location and cause obstruction, and are detected serendipitously on radiology as solitary pulmonary nodule. These lesions have heterogeneous appearance on radiology, thus radiology has a limited role in distinguishing pulmonary hamartoma from other causes of solitary pulmonary nodule which include malignancy, metastasis, granuloma or other benign neoplasms. The characteristic "popcorn" calcification is seen in only 10-30% of cases and CT can detect about 50% of hamartomas.6,7 Therefore, cytological and/or histopathological examination is required for a definitive diagnosis or at least to exclude malignancy.
Pulmonary hamartoma, a rare benign tumour of the lung -Case series
A B S T R A C TIntroduction: Pulmonary hamartoma, with incidence of 0.25-0.32%, accounts for 6% of solitary pulmonary nodules. The role of radiology is limited as only 10-30% of cases show characteristic 'popcorn' calcification and Computed Tomography can detect approximately 50% of hamartomas. Hence cytological and/or histopathological examination is required to make a definitive diagnosis and exclude malignancy. Objective: As pulmonary hamartoma is a rare entity detected serendipitously on radiography and requires cytological and histopathological examination for confirmation of diagnosis, we present nine cases of solitary pulmonary nodules which were diagnosed as pulmonary hamartoma. Methods: We retrospectively screened departmental records and slides and found nine cases of pulmonary hamartoma in our tertiary care institute (Post Graduate Institute of Medical Education and Research, Chandigarh, India). Three cases were diagnosed on CT guided Fine Needle Aspiration Cytology and four cases were diagnosed on histopathological examination ofsurgical specimens, over a period of 16 years (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012). Two cases were incidentally discovered to have pulmonary hamartoma at autopsy. Observations: The age of the patients ranged from 17-63 years (mean-46.3), with male to female ratio being 3.5:1. The size of the hamartoma varied from 0.4-1.3 cm, with mean diameter of 1 cm. Cytology showed mixture of bronchial epithelial cells, adipocytes and stromal fragments in fibromyxoid and chondroid background. Histopathology demonstrated lobules of cartilage and adipose tissue with intervening clefts lined by respiratory epithelium and mesenchymal stroma. Conclusion: Every solitary pulmonary nodule is not malignant. It is important to correctly diagnose pulmonary hamartoma, a rare, yet benign neoplasm presenting as a solitary lung nodule and distinguish it from malignancy.
