Figure 4. MIFS with BRAF amplification.
(A) Alternating myxoid and solid areas of histiocytoid tumor cells, accompanied by lymphocytic infiltrate and vascular proliferation. (B) Tumor cells with round to ovoid nuclei and occasionally prominent nucleoli (arrow). Reed-Sternberg-like tumor cells are not seen in this case. (C) BRAF amplification without rearrangement was identified by FISH.