In the derivation sample (93 subjects with PNI available, 34 of which died), age, occurrence of an AIDS defining event within six months from date of NHL diagnosis, no cART assumption, CD4 cell count lower than 200 cells/mm3 and PNI equal to 1 were significantly associated with fatal outcome in univariate Cox regression analysis (Table 5). This evidence concerns the gene CD4 and non-Hodgkin lymphoma.