Diagnostic and prognostic markers of cutaneous lymphomas

This thesis comprises immunophenotypic and molecular studies in several types of cutaneous lymphomas. These studies provide a better definition of the clinicopathologic entities and provide adjunctive diagnostic markers that may aid in diagnosis of these patients in routine diagnostics, including TOX expression in cutaneous T-cell lymphomas and MYC expression and MYC rearrangements in cutaneous B-cell lymphomas (CBCLs). Also, the results demonstrate that adverse prognostic factors in systemic lymphomas are not directly transferrable to cutaneous lymphoma patients, including TP63 rearrangements in primary cutaneous CD30+ lymphoproliferative disorders and double hit status in CBCL, underlining the importance of a separate classification system for cutaneous lymphomas. Finally, these studies may have consequences for the management and treatment of patients with cutaneous lymphomas, because of the identification of recurrent molecular alterations that could provide attractive targets for novel therapeutics, including MYD88 and CD79B mutations in patients with intravascular large B-cell lymphomas.