XPO1 and classic Hodgkin lymphoma: Finding the mutation XPO1 E571K in plasma ctDNA should be investigatedfurther in prospective research as it could be a potential biomarkerfor HL.61 Nevertheless, only 10–20%of individuals have XPO1 E571K, the only recurrent single mutation.Most HL lack a uniform biomarker for monitoring due to the lack ofextremely widespread mutations.61 In aretrospective analysis, the XPO1 E571K mutation was found in ctDNAfrom patients with cHL harboring the reporter using NGS techniquesand digital polymerase chain reaction (dPCR).