[Diagnostic approaches and clinical relevance of hereditary hematological malignancies].

Hereditary hematological malignancies (HHM) are characterized by genetic heterogeneity, variable penetrance, and expressivity. Although individual gene involvement is rare, germline pathogenic variants are estimated to be present in at least 5-10% of hematological malignancies. In cases diagnosed at young age, with positive family history, or with multiple malignancies (including myeloid neoplasms after cytotoxic treatments), the prevalence rises, reaching 13-21%. Germline-focused tumor analysis may suggest genetic predisposition even without clinical suspicion. Using larger gene panels or whole-exome sequencing can further increase the detection rate of pathogenic germline variants to over 20%. In HHM, peripheral blood/bone marrow samples may contain somatic and germline variants. Germline confirmation requires non-hematopoietic samples, such as hair follicles or fibroblast cultures. Identifying HHM has clinical implications, especially in the timing of allogeneic stem cell transplantation, donor selection, conditioning, and follow-up. Genetic screening and counseling are essential for predisposed patients and family members to provide interdisciplinary care.