Ancillary Tools for the Diagnosis of CIC -Rearranged Sarcoma: A Comprehensive Review.

This comprehensive analysis included 36 studies, encompassing 436 CIC-rearranged sarcomas.

The immunohistochemical markers, CD99 (typically non-diffuse), nuclear WT1, ETV4, and DUX4, were found to be relatively highly sensitive for CIC-rearranged sarcoma (CD99: 87%, WT1: 83%, ETV4: 85%, DUX4: 97%).

CIC break-apart FISH can be a helpful and cost-effective assay for detection of CIC-rearrangements, but has a false-negative rate that ranges from 26% to 43%.

Next-generation sequence RNA fusion analysis also carries a risk of false negatives, which may be partly mitigated through manual data review.