New research shows that giant cell tumor of bone (GCTB) may be excluded from differential diagnosis in pediatric patients due to assumptions based on adult patients’ presentation of the disease. Duke orthopaedic oncologists Julia Visgauss, MD, Will Eward, MD, DVM, and Brian E. Brigman, MD, PhD, were among the study’s authors. 

Traditionally, GCTB was believed to only affect the epiphyseal portion of bones, as seen in adults. Thus, when skeletally immature patients presented with lesions at metaphyseal sites, the differential diagnosis excluded GCTB. However, by reviewing the radiographs and case histories of Duke patients, the team found GCTB at metaphyseal sites of skeletally immature patients with open growth plates.

Properly diagnosing GCTB is important for many reasons. “Some other types of benign lesions in metaphyses don’t need intervention,” says Visgauss. “Although GCTB is considered benign, it is locally aggressive and can even metastasize to the lungs. These patients need to be treated surgically and surveilled with chest imaging because of the risk of pulmonary spread of the disease.”

Ignoring GCTB as a possible diagnosis also affects the patient’s treatment going forward. The study showed that metaphyseal GCTB recurred in up to 80% of patients with open growth plates. “It’s important to weigh the benefits and risks of protecting the growth plate versus how aggressive the surgery must be to address the tumor and lower the risk of recurrence,” Visgauss says. “Patients with suspected GCTB should be treated by orthopaedic oncologists who keep up with the rapid pace of treatment and management changes.”

Research like this study continues to move the field of orthopaedic oncology forward. Duke offers an expanding number of tests conducted on-site to find the right diagnosis. These include tests to identify molecular and genetic markers that increase diagnostic accuracy. These tests are important because giant cells can be found in several diagnoses, including aneurysmal bone cysts, chondroblastoma, and even giant cell-rich osteosarcoma.

Duke physicians work hard to find correct diagnoses and treatments, Visgauss says. “Our multidisciplinary teams meet regularly to review imaging and potential differential diagnoses for our cases, with pathology, radiology, medical oncology, radiation oncology, and surgical oncology reviewing cases together. In complex cases, it also gives us the opportunity to confer with multiple surgeons to make sure our treatment plan is the most appropriate, offering the best chance for a cure and minimizing morbidity.”