Solitary endobronchial plasmacytoma-a rare differential of an endobronchial mass

Abstract

Diagnostic dilemma, owing to the inconclusiveness of biopsy results, often leaves us with limited options to offer to the patients upfront, amongst the various armamentarium available. We hereby report a rare case of extramedullary plasmacytoma, whose diagnosis was established only on the final histopathology report with the aid of immunohistochemistry. A 50-year-old gentleman presented to our outpatient setup with computed tomography suggestive of a well-defined endobronchial mass occupying the left lower lobe bronchus. However, bronchoscopy and computed tomography-guided biopsies were inconclusive. After a routine metastatic workup, the patient underwent a left lower lobectomy following a provisional diagnosis of carcinoid on the frozen section. The final histopathology was solitary endobronchial plasmacytoma. Postoperative myeloma workup was within normal limits and the patient is doing well and disease free at 8 months of follow-up. This rare differential needs to be kept in mind while evaluating a case of well-defined endobronchial growth.

Keywords: Endobronchial; Myeloma; Plasmacytoma.

Fig. 1

a Computed tomography (CT) showing lesion encasing the basal trunk of the left lower lobe. b Gross section depicting variegated cut surface with segmental bronchus lumen as depicted by an arrow

Fig. 2

High-power magnification (left half) shows sheets of plasma cells with eccentrically placed nuclei and moderate eosinophilic cytoplasm, while immunohistochemistry (right half) shows lambda positivity