CT data help predict survival in metastatic melanoma
Computerized tomography (CT) imaging findings enhance the effectiveness of baseline serum lactate dehydrogenase (LDH) levels in predicting survival among persons with metastatic melanoma who are undergoing treatment with the angiogenesis inhibitor bevacizumab.
Andrew D. Smith, MD, PhD, of the University of Mississippi Medical Center in Jackson, Mississippi, and colleagues presented data from their exploratory study yielding this finding at the annual meeting of the American Roentgen Ray Society (ARRS), held in Washington, DC, April 14-19, 2013. Describing metastatic melanoma survival as “devastatingly low” in their meeting abstract, the investigators noted that a predictive biomarker could be used to guide therapy, reduce unnecessary drug-related toxicity, and improve patient counseling.
In an effort to identify clinical and CT parameters that are predictive of progression-free survival (PFS) and overall survival (OS) in persons with metastatic melanoma on bevacizumab therapy, Smith's team analyzed CT images and clinical data from 46 such patients in a phase II prospective trial. As Smith explained in an ARRS statement, persons with metastatic melanoma who have high baseline levels of serum LDH tend to have poor overall survival compared with patients with low levels, but LDH levels are only weakly associated with survival when considered alone.
The researchers were surprised to discover that the accuracy of predicting both PFS and OS substantially increased when data from serum LDH levels were combined with information from initial post-therapy CT imaging changes in tumor morphology, attenuation, size, and structure (MASS criteria).
The study demonstrated that an index combining baseline LDH and MASS criteria response on the first post-therapy CT has a high degree of predicting PFS of more than 9 months and OS of more than 2 years in patients who have metastatic melanoma and who are on bevacizumab therapy.