Among them, ARID1A, ATM, ATR, POLD1 and POT1 genes, all involved in genome maintenance and DNA repair (20), showed, with exception of POT1, a high frequency of mutation according to RNA-seq (ranging from 14% to 23%), suggesting a transcriptional active role in SS cells potentially favoring the onset of this lymphoma. Here, POLD1 is linked to synovial sarcoma.