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Abstract Multiple Myeloma (MM) is a malignant plasma cells disorder that account for the 15% of hematologic malignancies. The clinical manifestation is defined by the presence of anemia, renal failure, hypercalcemia and osteolytic bone lesions called with the acronym CRAB. Here we describe the case of a caucasian man referred to our Center for a clinical suspicion of MM. A comprehensive work-up, including blood tests, radiological examinations and bone marrow biopsy ruled out the presence of plasma cells neoplasm Further investigations as CT guided-biopsy of a lytic lesion allowed us to perform a diagnosis of brown tumor (BT), a tumor-like lesion due to the bone remodeling process in prolonged hyperparathyroidism. This diagnosis was confirmed by endocrinological evaluations followed by a parotidectomy with resolution of the clinical manifestations. Our case outlines the importance of an accurate differential diagnosis in the suspicion of MM, because the concomitant occurrence of comorbidities and illnesses may confound the evaluation, In particular the combination of anemia, peripheral neuropathies and renal impairment could be associated to a number of other causes and it is mandatory a thorough anamnesis, clinical and instrumental examination and laboratory investigations to rule out other etiologies.