A 70-year-old man with a past medical history of dyslipidemia was referred to Jeju National University Hospital with a 5-month history of recurrent vertebral compression fractures with back pain. He suddenly had back pain while changing his pants and was treated for T11 and L3 vertebral compression fractures 5 months prior. He had slipped down on the stairs, landing on his backside, and was hospitalized for treatment of L2 and L4 vertebral compression fractures 2 months prior. He had felt back pain while sneezing and had difficulty in walking 5 days prior. Eventually, he was referred to our hospital. Bone densitometry of the spine from previous hospital visits revealed osteopenia, and magnetic resonance imaging (MRI) of the lumbar spine from a previous hospital visit showed multiple compression fractures of the vertebral bodies with inconspicuous retropulsion of the cortex into the spinal canal (). X-ray images of the T-L spine () revealed degenerative changes with compression fractures at T12, and the L1 to L3 vertebral bodies and the pelvic bones () showed osteopenia. A bone scan () showed a vertebral compression fracture in the L1 spine area; post-traumatic changes in the right first and eighth to tenth ribs and the left sixth rib; and arthritic and degenerative changes in the T9 to L5 spines and both hip joint areas.\nLaboratory tests did not reveal specific results. The hemoglobin level was 11.0 g/dL, showing normocytic normochromic anemia on the peripheral blood smear. We also noted the absence of hypercalcemia (8.9 mg/dL), and a normal serum creatinine level of 0.78 mg/dL. Laboratory tests and imaging studies did not provide evidence to suspect that the recurrent compression fractures may have resulted from osteoporosis, metabolic diseases such as hyperparathyroidism, Paget disease and other metabolic processes, or obvious tumors. Therefore, serum and urine protein electrophoresis were conducted for the differential diagnosis of MM. Serum protein electrophoresis did not reveal abnormal Ig levels and the patient’s gamma globulin levels were normal. Urine protein electrophoresis showed no monoclonal protein in any significant fraction. Consequently, a presumptive diagnosis of vertebral compression fractures with osteopenia was made, and conservative management was undertaken for 2 weeks.\nHowever, the patient complained of right hip pain during his first ambulation after conservative management. Hip X-ray images () suggested several osteolytic lesions, and computed tomography detected multiple inconspicuous osteolytic lesions with greater variegation in opacity than expected in the spine, pelvic bones, both femurs, and ribs, suggesting MM or metastasis (). In addition, positron emission tomography revealed a high possibility of bone metastasis or bone-related malignancy based on a significant abnormal 18F-fluorodeoxyglucose uptake in the skull, spine, sternum, ribs, scapula, pelvic bones, and both femurs (). Moreover, a serum free light chain (SFLC) assay revealed elevated levels of kappa free light chain (12.667 mg/dL) and abnormal free light chain ratios with free lambda (1.105 mg/dL).\nTherefore, we performed a bone marrow biopsy for the definitive diagnosis of NSMM. The marrow was mildly to moderately hypercellular and infiltrated by plasmacytoid cells in clusters with some normal hematopoietic cells (). The plasmacytoid cells showed reactivity to CD138 () and kappa free light chain on immunohistochemical staining (), with no reactivity to lambda light chain (), which supports monoclonal plasma cell proliferation and favors the diagnosis of MM. Finally, the patient was diagnosed with NSMM 7 months since the onset of the first symptom and was referred to the oncology center for further management and therapy.
A 60-year-old man presented with a history of lower back pain that had persisted for 2 years and difficulty walking for 2 months. The patient received a complete hemogram as well as routine biochemical and radiographic imaging studies. His hemoglobin level was 15.3 g/dL, his total leukocyte count was 6.1×109/L, his platelet count was 160×109/L, and his erythrocyte sedimentation rate (ESR) was 15 mm. No rouleaux formation was seen on a peripheral smear. Serum blood urea nitrogen (27 mg/dL), creatinine (1.06 mg/dL), calcium (9.9 mg/dL), and albumin (5.1 g/dL) were all within normal limits. Serum uric acid levels were high (7.6 mg/dL), Alkaline phosphatase levels were slightly increased (134 U/L), and the patient had subnormal vitamin D3 levels. Ultrasonography findings were within normal limits, except for mild prostatomegaly. Serum prostate specific antigen and carcinoembryogenic antigen levels were within normal limits.\nA radiograph of the dorsolumbar spine showed diffuse osteoporosis and wedging of the D12 vertebra. Multiple small permeative lesions were seen in the pelvic bones and proximal femoral shafts. MRI findings showed diffuse degenerative changes in the cervical and lumbar spine and D12 vertebral collapse. Bone scan showed increased uptake in the anterior region of the 6th rib, left sacroiliac joint, and occipital region. Serum protein electrophoresis did not show any M spike, and gamma globulin levels were normal (8.8 g/L). Urine protein electrophoresis showed protein levels of less than 60 mg/L and no M spike. The bone scan findings, together with increased serum uric acid and alkaline phosphatase levels, and negative myeloma workup suggested possible diffuse skeletal metastasis. The patient underwent bone marrow aspiration from the bilateral posterior iliac spines and unilateral trephine biopsy to look for any secondary causes of bone scan findings and to rule out the presence of a plasma cell neoplasm. The aspirates from both sides showed similar findings, with numerous plasma cells ranging from 60–70% (). Binucleated or multinucleated forms, plasmablasts, and occasional mitotic figures were also observed in those plasma cells. Additionally, intranuclear Dutcher bodies and occasional Mott cells were observed. The Congo red stain for amyloid on the trephine biopsy was negative. IHC was performed on the trephine biopsy, revealing cells positive for CD138, MUM 1, and cytoplasmic κ and negative for CD3, CD20, LCA, CD56, and lambda (λ). The Ki-67 labelling index was 15%. The mean λ FLC level was 11.2 mg/L (range, 5.5–26.3 mg/L), and that of κ was 176.8 mg/L (range, 3.3–19.4 mg/L). The mean κ/λ ratio was 15.78 (range, 0.2–1.65). Patient had high β2-microglobin levels, at 2,557 mg/mL (range, 609–2,366 mg/mL).\nThe patient was in clinical stage I according to the International Staging System (ISS) for plasma cell myeloma and stage IIIA according to the Durie-Salmon staging system. The patient was referred to the oncology center for further management. There the patient was treated with a chemotherapy regimen that included the proteasome inhibitor bortezomib and dexamethasone.