What is the role of radiation in a patient with stage IV DLBCL with bilateral testicular involvement?

I tend to loosely recommend consolidation RT to the testicles in this situation if in CR. This recommendation is based on pattern-of-failure studies in primary testicular lymphoma where prophylactic contralateral testes RT is usually recommended, and the principle that the testicles are a sanctuary site, recognizing that a patient with Stage IV DLBCL likely has additional competing risks for relapse elsewhere (as compared to someone with more localized testicular lymphoma).

Zucca et al., PMID 125...