KITneg. AdvSM can be subdivided into (i) patients with other mutations at codon 816 such as KIT D816H/N/Y, most frequently associated with an MCL phenotype, (ii) KITneg. MCL with a very poor prognosis despite the absence of C-findings and HRM (iii) KITneg. SM-AHN with low MC burden and dominating AHN, making SM-specific treatment dispensable and prognosis mainly triggered by AHN. Here, KIT is linked to mantle cell lymphoma.