MGUS, Shoulder Pain, Swelling

On examination, a soft swelling was palpable on left shoulder region, which was nontender.

Figure 1. On X-ray imaging, AP and LATERAL views a large, well-defined expansile lytic lesion with wide zone of transition is noted involving head of left humerus and scapula associated with cortical destruction.

Figure 2. On NECT axial, coronal and saggital image, a large soft tissue mass lesion is noted superolaterally of head of left humerus involving supraspinatus, infraspinatus, and deltoid muscle associated with medullary expansion, endosteal scalloping and punched out cortical destruction.

Figure 3. On NECT axial, coronal and saggital image, a large soft tissue mass lesion is noted superolaterally of head of left humerus involving supraspinatus, infraspinatus, and deltoid muscle associated with medullary expansion, endosteal scalloping and punched out cortical destruction.

Figure 4: On MRI axial, saggital and coronal image, the cyst appears hypointense on T1, hyperintense on T2 pulse sequences.

Diagnosis: Multiple myeloma

On MRI left shoulder, a large altered signal intensity soft tissue mass lesion is noted superolaterally to head of left shoulder hypointense on T2 and iso to hypointense on T1 pulse sequences, hyperintense on PD fat sat.

Multiple myeloma is the most common primary malignancy of the bone.

Multiple myeloma is a hematologic malignancy of bone marrow plasma cells.

Patients are stratified according to the risk level associated with their specific monoclonal gammopathy to identify those who are in need of close monitoring.

Plasma cell leukemia is a more aggressive form of multiple myeloma that is characterized by a proportion of circulating plasma cells of more than 20% at the time of initial diagnosis or at disease progression.

Multiple genetic factors have been identified that correlate with prognosis.

Multiple myeloma staging has traditionally relied on serum and urine markers of disease as well as conventional radiography.

The presence and number of lytic lesions identified in the radiographic skeletal survey may alter disease staging, and these data are an integral part of the original Durie and Salmon staging system.

Multidetector CT provides useful information in the evaluation of lytic bone marrow lesions.

Marrow disease in the presence of multiple myeloma is identifiable at MR imaging as areas of decreased fat and increased signal intensity within the marrow on T1-weighted images.

Stem cell transplantation is usually performed in patients younger than 65 but may be performed in older patients if they can tolerate the treatment.