A voluminous mass as an initial clinical symptom of multiple myeloma: A case report

Abstract

Abstract. Extramedullary multiple myeloma (EMM) is a type of multiple myeloma (MM) that is defined by the presence of extraskeletal (soft tissue or visceral) clonal plasma cell infiltrates, which may be present at the time of initial diagnosis or at the time of relapse. Although extramedullary lesions may be present with other clinical features at the time of diagnosis, the onset of a solid formation as a first clinical symptom of MM is unusual. The present study reports the case of a 77-year-old male who was admitted to the Hematology Unit of the National Cancer Research Center, Istituto Tumori 'Giovanni Paolo II' (Bari, Italy) with a mass protruding from the right side of his lower back. Serum immunofixation revealed positivity for monoclonal protein (M-protein) and Bence Jones proteinuria was positive. In addition, a computed tomography scan of the abdomen, which was confirmed by magnetic resonance imaging, revealed a voluminous solid formation resembling a sarcoma. M-protein is known to be present in numerous diseases encountered in clinical practice, including hematological or other diseases; thus, a Tru-Cut biopsy of the lesion was performed, which revealed an infiltration of plasma cells. In addition, a bone marrow biopsy revealed the presence of 70% plasma cells, and a diagnosis of primary EMM was established. In conclusion, EMM should be included in the differential diagnosis of a mass, particularly in patients where M-protein is detected in the blood and/or urine.

Atypical Presentation of Plasma Cell Neoplasm of the Sternum

“…MM belongs to a family of monoclonal gammopathies; monoclonal gammopathy of undetermined significance (MGUS) and asymptomatic/smoldering myeloma accounting for about 1% of all cancers [ 1 ]. It is regarded as the most common primary bone cancer in older patients with a median age of onset of about 65 years [ 2 , 3 ]. In the United States, MM has an incidence of about 30,000 new cases per year, and in 2018, more than 10,000 people died of this disease [ 3 ].…”

“…According to the International Myeloma Working Group (IMWG), early diagnosis of MM requires the presence of ≥10% monoclonal plasma cells in the bone marrow or plasmacytoma, an increased ratio of serum-free light chains (kappa: lambda), and positive imaging findings [ 4 ]. Symptomatic features like bone pain, fatigue (anemia), kidney failure, and hypercalcemia help differentiate smoldering (asymptomatic) from symptomatic MM [ 2 ]. Although on physical examination there was a presence of a sternal hard mass in our patient, he complained of bone pain (manubrium) and bone marrow biopsy revealed 70% monoclonal plasma cells, which helped make the accurate diagnosis of symptomatic MM.…”

“…The diagnosis is confirmed by the presence of ≥10% of monoclonal plasma cells in the bone marrow or end-organ damage (symptomatic MM). Usually, plasma cells are confined in the bone marrow in patients with MM, but extramedullary infestations presenting as a mass have also been reported in the medical literature [ 2 ].…”

“…While the etiology of extramedullary myeloma (EM) is unknown, an initial presentation is rare and therefore a detailed physical examination, imaging studies, laboratory results, and core-needle/bone marrow biopsy are required to make an accurate diagnosis [ 2 ]. We present a case of a 65-year-old male who presented to the emergency department (ED) for an evaluation of a chest mass after an episode of chest pain.…”