Should myeloid and lymphoid neoplasms with PCM1-JAK2 and other rearrangements of JAK2 be recognized as specific entities? Since the publication of the 2001 and 2008 World Health Organization classifications of tumours of haematopoietic and lymphoid tissues, there has been an increasing move towards classification of haematological neoplasms on the basis of the underlying molecular genetic disorder.    ///    Should myeloid and lymphoid neoplasms with PCM1-JAK2 and other rearrangements of JAK2 be recognized as specific entities?.     ///    PCM1-JAK2 fusion should be recognized as an entity. 