Pathologic fractures in myeloma patients undergoing bisphosphonate therapy do not indicate disease progression, according to a recent article published in the American Journal of Roentgenology.

Pathologic fractures are bone breaks in an area already weakened by another disease process. Myeloma tumors weaken bone, and pathologic fractures are frequent complications for myeloma patients. In fact, thirty percent of patients are diagnosed with myeloma after developing this type of fracture.

Bisphosphonates, given in conjunction with chemotherapy drugs, are the most common treatment for myeloma bone disease. Bisphosphonates inhibit the activity of osteoclasts, which are cells that break down bone. This class of drugs does not directly treat myeloma tumors, but it helps reduce the pain and bone fractures caused by the cancer.

The current study observed 191 myeloma patients receiving bisphosphonate therapy. Researchers followed the patients for an average of 23 months. During this time the study participants underwent at least two whole-body, low-dose multi-detector computed tomography (MDCT) examinations. MDCT is a form of medical imaging used to identify pathologic fractures.

Pathologic fractures were detected in 19 percent of patients. However, the fractures discovered in MDCT images were found to be unrelated to disease progression. Fractures were found in 12.4 percent of MDCT scans of patients with progressive disease, in 8.2 percent of MDCT scans in patients with disease remission, and in 5.3 percent of MDCT scans in patients with stable disease. As a result, the researchers concluded that pathologic fractures should not be considered a sign of disease progression.

For more information, please see the original article in the American Journal of Roentgenology (abstract).