Pulmonary Adenofibroma in an Elderly Male with Recurrent Soft Tissue Sarcoma

Abstract

Pulmonary Adenofibroma (PAF) is a rare soft tissue tumour of the lung. It is a benign lesion, having a biphasic pattern with an admixture of epithelial and stromal components and has resemblance to fibroadenoma of the breast and adenofibroma of the female genital tract. The diagnosis can be challenging and it has to be delineated from other entities with biphasic pattern, like pulmonary hamartoma, pulmonary blastoma, intrapulmonary solitary fibrous tumour and metastases from soft tissue and visceral sarcomas, as each tumour has its own therapeutic and prognostic implications. Here, we report a case of a 73-year-old male, a known case of recurrent soft tissue sarcoma of the thigh, who presented with solitary pulmonary lesion. The patient was a non-smoker and did not have any specific respiratory complaints. On staging work-up with a Positron Emission Tomography and Computed Tomography (PET-CT), a hypermetabolic lesion was identified in the anterior segment of right upper lobe of the lung, following which he underwent right lobectomy. The tumour was a solitary lesion located near the hilum and on histology showed a biphasic pattern with scattered glandular spaces lined by columnar epithelium set in a hyalinised spindle cell stroma. The cells showed mild pleomorphism with oval to elongated nuclei and indistinct cytoplasm. On immunohistochemistry, the epithelial component showed positivity for Cytokeratin (CK), Epithelial Membrane Antigen (EMA), Thyroid Transcription Factor-1 (TTF-1) and Napsin-A and the stromal component showed positivity for Vimentin, Desmin, Smooth Muscle Actin (SMA) and H-Caldesmon (High molecular weight isoform-Caldesmon). With the given histological and immunohistochemistry findings, a diagnosis of PAF was rendered.