Five cases of orbital extramedullary plasmacytoma: diagnosis and management of an aggressive malignancy.

: Multiple myeloma is an insidious haematological malignancy characterised by monoclonal proliferation of plasma cells in the bone marrow. Extramedullary plasmacytoma is a rare manifestation of multiple myeloma and usually occurs in the upper respiratory tract. Orbital involvement is particularly uncommon, but may be associated with devastating visual impairment and poor clinical outcomes. Therefore, this article aims to highlight the need for multidisciplinary management of orbital extramedullary plasmacytoma. : This is a retrospective observational case series of five patients. All presented to the authors for management of orbital extramedullary plasmacytomas from 2004 to 2015 at Prince of Wales and Mater Hospitals in Sydney, Australia. Medical records were reviewed for pertinent information including demographics, disease features, management strategy, and clinical progress. The study met Medical Ethics Board standards and is in accordance with the Helsinki Agreements. : This case series of five patients underscores the poor prognosis of orbital extramedullary plasmacytoma. Despite aggressive multidisciplinary management, four of these five patients succumbed to their illness during the study period. However, multidisciplinary management did manage to minimise symptoms and preserve quality of life. : On a case-by-case basis, patients may derive palliative benefit from orbital surgery in conjunction with radiotherapy and chemotherapy. Orbital surgeons are encouraged to work within a multidisciplinary framework of medical specialists, including haematologists and radiation oncologists, when determining the optimal management plan in cases of orbital extramedullary plasmacytoma.