THE RELATIONSHIP OF BRAF MUTATION STATUS TO FDG PET/CT AVIDITY IN THYROID CANCER: A REVIEW AND META-ANALYSIS.

Objective: Papillary thyroid cancer (PTC) harboring a BRAF gene mutation has been shown to exhibit aggressive tumor behavior and carries higher risks of recurrence and disease-specific death. In this systematic review and meta-analysis, we examined published evidence related to the accuracy of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in detection of residual disease in patients with BRAF mutated thyroid cancer.

Methods: We extracted data from PUBMED/MEDLINE and EMBASE published between January 1995 and March 2017. We included studies that compared FDG PET standardized uptake values (SUVs) between BRAF-positive and BRAF-negative subjects, as well as those that evaluated the odds of having FDG avidity between BRAF-positive and -negative patients with thyroid cancer.

Results: There were a total of 12 studies in the systematic review. Seven studies qualified for the analysis for calculating the pooled odds ratio (OR). The pooled cohort with binary data had 1,144 patients out of which 843 were BRAF positive and 301 were BRAF negative. Those with a BRAF mutation had a significantly greater likelihood of having FDG-avid lesions. The pooled OR was 2.12 (confidence interval [CI] 1.53-3.00, P<.01). The pooled mean SUV (cohort of 315 patients) was significantly higher in BRAF-positive compared to BRAF negative patients, with a pooled mean difference of 5.1 (CI 4.3-5.8).

Conclusion: Our meta-analysis shows that presence of BRAF mutation in PTC confers a higher likelihood of FDG PET avidity and is associated with higher SUV uptake values compared to BRAF-mutation negative status.

Abbreviations: BRAF = B-Raf proto-oncogene, serine/threonine kinase; CI = confidence interval; CT = computed tomography; DTC = differentiated thyroid cancer; FDG = fluorodeoxyglucose; PET = positron emission tomography; PTC = papillary thyroid cancer; SUV = standardized uptake value.