Primary pulmonary plasmacytoma presenting with rare IgG lambda monoclonal gammopathy

Extramedullaryplasmacytoma (EMP) represents a peculiar and typically progressive malignancy that can originate outside the bone marrow. Primary pulmonary plasmacytoma (PPP) is a rare subset of EMP, confined to the lung. A 55-year-old man, diabetic, non-smoker presented to our clinic with a right chest wall swelling. A routine chest radiograph showed a well-circumscribed opacity in the right upper lung zone. A CT of the chest revealed a large right upper lobe mass with extensive local infiltration. Biopsy and immunohistochemical evaluation led to a diagnosis of PPP. Screening for multiple myeloma was negative. Serum immunofixation showed an IgG lambda monoclonal gammopathy, found in a minority of PPP patients. In view of disease extent, treatment with chemotherapy and radiotherapy was initiated. The patient is currently in out patient follow-up and has shown a favourable response to the treatment with a considerable decrease in serum IgG levels.