RESUMO
Solitary plasmacytoma is a rare clonal plasma cell tumor, representing 2-5% of plasma cell disorders. The standard treatment is local radiotherapy. However, in some cases, its use is limited by the size and/or location of the mass. Systemic chemotherapy may be a useful therapeutic alternative. We describe a case of a 27-year-old male with a bulky solitary plasmacytoma arising in the posterior mediastinum, causing spinal cord compression. Radiotherapy was considered risky as the mass was located in the heart and left lung fields. Systemic treatment was given. After the first cycle of cyclophosphamide, bortezomib, and dexamethasone (VCD), the patient attained full neurological recovery. After four VCD cycles, complete remission was achieved. Autologous stem cell transplantation was given as consolidation therapy. At 3 months post-transplantation, the patient is in full clinical recovery and complete metabolic remission on 18FDG PET-CT. Although infrequent, plasma cell disorders must be considered in adult patients with a bulky tumoral mass in the posterior mediastinum. PET-CT is the whole-body imaging technique of choice to detect SP, to evaluate response to treatment and during follow-up.
RESUMO
Extramedullary plasmacytoma (EMP) represent 3% of plasma cell neoplasms. Approximately 80-90% of EMPs involve the mucosa-associated lymphoid tissue of the upper airways and 75% of these involve the nasal and paranasal regions, while renal or retroperitoneal infiltration is very rare. EMPs are highly radiosensitive, with excellent results. The local control rate of radiotherapy can reach 90-97% and the 5-year overall survival rate can be 57-61%. EMP has an indolent course and the prognosis is generally favorable, with 70% of the patients remaining disease free for 10 years. However, about 30% may progress to plasma cell myeloma or relapse. Here, we report a case of a huge retroperitoneal solitary extramedullary plasmacytoma that grew rapidly.
