A fit and healthy female patient was exercising when she has severe pain in her left arm. X-rays of the humerus, skull and chest as well as CT scans and related blood chemistry comfirmed the diagnosis of pathological fracture, malignant hyperparathyroidism, solitary osseous plasmacytoma and multiple myeloma.
The patient was asymptomatic and was exercising when she experienced severe pain in her left arm. X-rays of the humerus (Fig 1) showed a mid-shaft transverse fracture through an osteolytic lesion. Sub-cortical bone resorption (brown tumors) was also noted (Fig 2). X-rays of the skull showed multiple osteolytic lesions (Fig 3). X-rays of the fingers showed sub-periosteal bone resorption (Fig 5). Chest X-rays showed a 3-4 cm diameter soft tissue mass projected over the anterior end of the right 3rd rib and into the chest cavity with multiple lytic lesions in the ribs (Fig 4). This chest lesion was seen on Computer Tomography (CT) (Fig 6) and noted to be involving the 3rd rib (Fig 7). A solitary metastasis was also noted in the liver on CT scan (Fig 8). It was confirmed to be a plasmacytoma involving the 3rd rib on CT guided biopsy and histology. Biochemical investigations showed hypercalcaemia (Ca 2.7mmol/l), hypophosphataemia (PO4 0.44mmol/l), elevated alkaline phosphatase (ALP 182u/l) and a low parathormone (5 pg/ml). Protein electrophoresis revealed light chain monoclonal immunoglobulins and bence-jones proteins. The humeral fracture was fixed with a retrograde intra-medullary nail and the patient underwent a course of radiotherapy.
Malignant hyperparathyroidism occurs due to production of parathyroid- related proteins(PTHrP) by some tumours, particularly of pulmonary origin. The PTHrP mimics PTH resulting in hypercalcaemia and a low PTH. Radiographic signs of hyperparathyroidism result. These include sub-cortical bone resorption also called brown tumors(1) or osteitis fibrosa et cystica. This was evident in the humeral diaphysis adjacent to the pathological fracture. Sub-periosteal bone resorption also occurs, especially in the hands(2). Another sign is the ‘pepper-pot skull’ due to multiple osteolytic lesions. This is also seen in multiple myeloma. Plasmacytomas are plasma cell tumours. They can be of bony origin i.e. osseous plasmacytomas, and are then usually solitary, or originate from soft tissues i.e. extramedullary plasmacytomas (EMP). Their prognosis depends on their ability to progress to multiple myeloma. Progression is more likely in solitary osseous plasmacytomas (SOP) which thus have the worse prognosis. Knowling in his series found that 16% of patients with SOP who were treated with radiotherapy were progression free at 10 years in comparison to 71% of EMP patients(3). Bolek in a retrospective review of 37 patients concluded that radiotherapy was an effective local treatment for solitary plasmacytomas[4]. In our case the chest lesion originated from the 3rd rib and CT guided biopsy confirmed a plasmacytoma. Bence-jones proteins and light chain monoclonal immunoglobulin confirmed multiple myeloma. This case shows how relatively advance disease can present incidentally (in this case as a pathological fracture) and how plasmacytoma can produce malignant hyperparathyroidism and progress to multiple myeloma.
This case involves a 66-year-old female patient whose chief complaint is sudden severe pain in the left arm during movement. Based on the provided X-ray, CT images, and clinical data, the main radiological findings are as follows:
Based on the above imaging features and the patient’s clinical background (including localized pain, pathological fracture, hypercalcemia, biochemical findings suggesting elevated PTH-related protein or reduced PTH, and pathological results of plasmacytoma), the following diagnoses or differential diagnoses can be considered:
Considering the patient’s age, symptoms, imaging findings (fracture, lytic “pepper-pot” appearance, “brown tumor”-like changes), laboratory data (hypercalcemia, elevated PTHrP, suppressed PTH), pathological findings (confirmed plasmacytoma), and other test results (e.g., Bence-Jones protein, light-chain monoclonal immunoglobulins), the most likely conclusion is:
In this case, the solitary bone plasmacytoma of the rib (verified by biopsy) has progressed to multiple myeloma. Under the background of malignant hyperparathyroidism, skeletal changes (such as brown tumors, osteolysis, and pathological fractures) further support this diagnosis.
In light of the risk of pathological fractures and bone fragility, a stepwise, individualized rehabilitation and exercise plan should be implemented:
Special Considerations: Because of the bone fragility, constantly monitor for any exacerbation of pain or discomfort during exercise. If significant pain or signs of new fracture occur, promptly evaluate and modify the exercise program.
This report is a reference-based analysis derived from the provided imaging and clinical information and does not replace an in-person diagnosis or the advice of a professional physician. Specific treatment and rehabilitation plans should be determined by the patient’s actual condition and the assessment of a professional medical team.
