FISH: EWING SARCOMA (EWS), 22q12 (EWSR1) REARRANGEMENT

EWING SARCOMA IS THE SECOND MOST COMMON MALIGNANT BONE TUMOR IN CHILDREN AND YOUNG ADULTS. THIS TUMOR IS CHARACTERIZED BY SPECIFIC GENE REARRANGEMENTS OF WHICH THE MOST COMMON IS THE FUSION BETWEEN EWSR1 GENE ON CHROMOSOME 22 & THE ETS FAMILY OF TRANSCRIPTION FACTORS OR RARELY FUS SUBSTITUTES EWSR1. FISH ANALYSIS TO IDENTIFY A COMMON TRANSLOCATION T(11;22)(Q23;Q12) OR LESS FREQUENTLY T(21;22)(Q22;Q12) OR T(7;22)(P22;Q12), PLAYS AN IMPORTANT ROLE IN THE CONFIRMATION OF CLINICAL DIAGNOSIS OF EWING SARCOMA FAMILY OF TUMORS (ESFT). THIS GENETIC ABNORMALITY IS FOUND IN 90 95% PATIENTS WITH EWING SARCOMA.