NFKB2 and primary cutaneous T-cell non-Hodgkin lymphoma: Complex chromosomal rearrangements or fusion events are rare and also highly heterogeneous (TYK2-UPF1, COL25A1-NFKB2, FASN-SGMS1, SGMS1-ZEB1, SPATA21-RASA2, PITRM1-HK1, or BCR-NDUFAF6, among others) but they represent interesting candidates as potential biomarkers or therapeutic targets in CTCL.