Imaging manifestations and clinical diagnosis of phosphaturic mesenchymal tumor / 中华放射学杂志

ABSTRACT

Objective To investigate the clinical and imaging characteristics of phosphaturic mesenchymal tumor and improve the clinical diagnosis. Methods From November 2014 to September 2017, 22 patients with pathologically confirmed diagnosis as phosphaturic mesenchymal tumor (PMT) were retrospectively analyzed, including 12 males and 10 females, age ranged from 30-72 years, mean (47 ± 11) years old. The clinical data, laboratory tests [serum calcium, phosphorus, alkaline phosphatase, parathyroid hormone and 1, 25- (OH) 2 D] and imaging examinations (X-ray, CT, MRI, nuclide) were collected and explored. Sixteen patients underwent SPECT scan and seven underwent PET/CT scan. Twenty patients had X-ray, eighteen patients had CT and 12 patients had MRI with enhancement. Results All patients suffered from diffuse pain for one to fifteen years, especially in lower back and lower extremities. All patients were found with low serum phosphorus, normal serum calcium. Twenty-one patients were found with elevated alkaline phosphatase, 16 with increased parathyroid hormone and 15 with decreased 1, 25 - (OH) 2 D. Thirteen lesions were located in the medullary cavity, seven in the soft tissue and two in the sinuses. Nineteen cases showed varying degrees of trabecular bone sparse, osteoporosis and osteomalacia on X-ray;There were 15 cases of multiple pseudo-fractures, including four cases of pelvic fracture complicated with femoral fracture, six cases of single fracture of pelvis, four cases of femur and one case of fibula. And seven cases showed multiple vertebral compression fractures. Thirteen lesions showed soft-tissue density and four in the medullary cavity showed high density on CT scan. The lesions presented low signal intensity on T1WI,high or low signal intensity on T2WI FLAIR and obviously enhanced in 12 patients who underwent MRI enhancement. Conclusion For patients with decreased serum phosphorus, elevated alkaline phosphatase, bone softening and fracture, octreotide or other nuclides should be primary imaging modality for confirming the location of the lesion. CT and MRI can further evaluate the nature of the lesion and improve diagnostic accuracy.