ACTG1 and Hodgkins lymphoma: To be included in the review, studies had to meet the following PICOS criteria: (1) population: patients affected by ACTB or ACTG1 variants; (2) intervention: description of clinical characteristics in subjects with ACTB or ACTG1 variants; (3) control: subject without ACTB and ACTG1 variants or studies/subjects without clinical description; (4) outcomes: presence of HL; and (5) study design: clinical studies with clinical characteristic description.