“…Pediatric series from Argentina exhibited a profile compatible with early cHL (i.e., younger ages, EBV positivity of ~50% and HL-MC as the predominant subtype) [ 20 , 25 , 26 , 27 ], while adult HL displayed a 31% of EBV-association, with similar frequencies of both NS and MC subtypes [ 22 ]. On the other hand, in the Southeast of Brazil, EBV positivity was 40–50%, HL-NS was the predominant subtype, and there was a smooth peak between adolescents and young adults [ 38 , 41 , 42 , 43 , 44 , 45 , 47 , 52 , 58 , 60 , 66 , 67 , 68 , 69 , 70 , 73 ], which may suggest a transition state in the epidemiology of the disease presentation between the ones observed in developing and developed areas. Indeed, one study in the most affluent Brazilian State (Sao Paulo) reviewed 817 cases of cHL over 54 years (1954–2008), describing that EBV-positive cases showed a decrease from 87% to 46% during the time of the study, with a remarkable decrease in young adults (85% to 32%) [ 32 ].…”