While mice of all genotypes developed a similar frequency of sarcoma, it was interesting that Ptprd−/−Cdkn2a−/− mice developed significantly more histiocytic sarcomas than soft tissue sarcomas, suggesting that loss of both copies of Ptprd can preferentially promote the development of cancers with hematopoietic origin (Figure 3B, p<0.05). This evidence concerns the gene PTPRD and histiocytic sarcoma.