Assessment of Minimal Residual Disease in Ewing Sarcoma
Figure 3
Use of FISH to detect Ewing sarcoma cells. (a) Fluorescence in situ hybridization (FISH) signal pattern for normal cells using the EWSR1 break-apart probe (Abbott Molecular) showing two fusion signals (red and green signal next to each other with little to no gap in between the signals), which is the normal pattern. (b) FISH signal pattern from normal cells with an occasional false-positive signal pattern (separation of one of the red and green signal pairs with a gap between the two signals wider than the size of one signal alone; see arrows) for EWSR1 rearrangement. (c) In a sample containing Ewing sarcoma, there is widespread separation of one signal pair in multiple tumor cells (labeled as 1R1G1F), compared to normal cells (labeled as 2F).
