Related Experiment Video
Updated: Sep 6, 2025

Author Spotlight: Advancing VRL Diagnosis Using Cell-Free DNA Extraction from Vitreous Humor
Published on: January 12, 2024
Central Nervous System Progression in Primary Vitreoretinal Lymphoma with Bilateral and Unilateral Involvement: A
Josephus L M van Rooij1, Klaudia A Tokarska1, Ninette H Ten Dam-van Loon2
1Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands.
Background:
Primary vitreoretinal lymphoma (PVRL) is either unilateral or bilateral at initial presentation. Progression to a central nervous system (CNS) lymphoma is regularly observed and these patients seem to have an inferior survival. Knowledge of the predictive value of laterality for CNS progression may facilitate risk stratification and the development of more effective treatment strategies, and eventually, improve outcomes. The objective of this analysis is to estimate the risk of CNS progression for patients with bilateral versus unilateral involvement of PVRL.
Methods:
Systematic literature search for studies on CNS progression in PVRL with bilateral and unilateral involvement according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We assessed the risk of bias and the methodological quality of studies using the Quality in Prognosis Studies (QUIPS) tool. Risk ratios of CNS progression in PVRL with bilateral and unilateral involvement were calculated and combined via a meta-analysis.
Results:
Twenty-five small-sized (total n = 371 cases) studies were included. The majority of the studies were at medium to high risk of bias. Results suggest no significant difference in CNS progression between bilateral and unilateral PVRL, with a pooled relative risk ratio of 1.12 (95% confidence interval 0.89-1.41).
Conclusions:
CNS progression is common in PVRL. From the limited available evidence, there is no significant difference in CNS progression between bilateral and unilateral PVRL.
Related Concept Videos
Primary Lymphoid Organs
The red bone marrow is a soft, spongy tissue nestled in the interior of long bones such as the humerus and femur. It is the site...
Secondary Lymphoid Organs
The spleen is a vital organ in the lymphatic system, nestled in the upper left side of the abdomen. It is composed of two primary regions: the red pulp and the white pulp, each having distinct functions. The red pulp performs a significant role in blood filtration. It efficiently purges the blood of old or damaged red blood cells and...
Tumor Progression
Colon cancer is one of the best-documented examples of tumor progression. Early mutation in the APC gene in colon cells causes a small growth on the colon wall called a polyp. With time, this polyp grows into a benign, pre-cancerous tumor. Further...

