INTRODUCTION: Currently, the detection of pathogens or mutations associated with intraocular lymphomas heavily relies on prespecified, directed PCRs. With metagenomic deep sequencing (MDS), an unbiased high-throughput sequencing approach, all pathogens as well as all mutations present in the host's genome can be detected in the same small amount of ocular fluid.

METHODS: In this cross-sectional case series, aqueous fluid samples from two patients were submitted to MDS to identify pathogens as well as common and rare cancer mutations.

RESULTS: MDS of aqueous fluid from the first patient with vitreal lymphoma revealed the presence of both Epstein-Barr virus (HHV-4/EBV) and human herpes virus 8 (HHV-8) RNA. Aqueous fluid from the second patient with intraocular B-cell lymphoma demonstrated a less common mutation in the gene associated with B-cell lymphoma.

CONCLUSION: MDS detects pathogens that, in some instances, may drive the development of intraocular lymphomas. Moreover, MDS is able to identify both common and rare mutations associated with lymphomas.