Monoclonal plasma cell proliferative diseases such as multiple myeloma and plasmacytoma can involve extramedullary sites at the time of first presentation, or subsequently in the course of the disease. Under such circumstances, they can mimic primary or metastatic carcinomas, neuroendocrine or neuroectodermal tumours and lymphomas, and the pathologist often has to resort to immunohistochemistry as an aid to diagnosis. We studied the morphology and immunohistochemical properties of 10 cases of previously confirmed monoclonal plasma cell proliferative lesions retrieved from the files of the Department of Pathology, University of Malaya. Serial 4u thick paraffin sections were stained with H&E, the Unna-Pappenheim technique for nucleic acid and a panel of antibodies using a standard immunoperoxidase technique. Light chain restriction was demonstrable in most of the cases. Seven (70%) showed kappa and 2 (20%) lambda light chain restriction. The remaining case was not stainable with most of the antibodies in the panel. The majority (80%) of cases showed accompanying IgG heavy chain in the cytoplasm, while 1 case had IgA. Seven (70%) showed membrane positivity with antibody to epithelial membrane antigen (EMA) and 7 (70%) cytoplasmic positivity with antibody to vimentin. This study enhances our awareness that neoplastic plasma cells can be positive for EMA and vimentin, and cautions us from misinterpreting these lesions as carcinomas or sarcomas. Notwithstanding that, immunohistochemical staining for kappa and lambda light chains can be helpful in differentiating monoclonal plasma cell proliferations from polyclonal ones.
Primary extramedullary plasmacytomas of the eyelid are rare with only five other cases reported in the literature. A 43-year-old Chinese man presented with painless swelling of the left lower eyelid that developed over the past two years. An incisional biopsy and histopathological analysis of the lesion revealed a primary extramedullary plasmacytoma of the eyelid. The tumour was completely excised. There has been no tumour recurrence over the last five years. This tumour should be among those considered when encountering an atypical adnexal lesion. A systemic examination, relevant clinical investigations, as well as life-long monitoring are essential for these patients due to the strong association of extramedullary plasmacytoma with multiple myeloma. When a lesion can be completely resected, surgery provides similar results to radiotherapy.
We describe a patient with multiple myeloma, who initially responded to chemotherapy and went into remission. She presented 10 months later with a right breast lump which was confirmed by core biopsy to be a plasmacytoma. Further treatment with radiotherapy, thalidomide and later second line chemotherapy appeared unsuccessful and she showed rapid disease progression with rising paraproteins and new extramedullary plasmacytoma lesions in the forehead, supraclavicular region, nasopharynx, liver, spleen, pancreas and paraaortic lymph nodes.
Extramedullary plasmacytoma is a rare plasma cell proliferative disorder with a predilection for the head and neck region. Occasionally, it presents as a solitary lesion in the nasal cavity. We report a case of an isolated lesion in the middle turbinate of the right nasal cavity. The lesion was completely excised via an endoscopic approach. We also review the pathology and management of plasmacytomas in general.
Extramedullary plasmacytoma is a rare malignant plasma cell tumour. We report an extremely aggressive case of extramedullary plasmacytoma of the right maxillary sinus, which had metastasised to the brain and rib. A 56-year-old man presented with recurrent epistaxis and acute anaemia. Nasendoscopy revealed a medialised medial wall of the right maxilla and a mass occupying the whole nasopharynx. Magnetic resonance imaging revealed a right maxillary tumour with extension to the ipsilateral nasal cavity, nasopharynx, right sphenoid and ethmoidal sinuses. There was an extra-axial brain metastasis. There were metastases to the right parietal region and left eighth rib. Histopathology examination of the maxillary mass revealed abundant plasma cells with kappa-chain restriction. He was planned for four cycles of chemotherapy. Unfortunately, in view of the advanced stage of disease, he succumbed to his disease during the first cycle of chemotherapy.