Counseling Patients about Rare but Serious Harms: The Importance of Absolute as well as Relative Risks.

Systematic literature review of treatment efficacy of previously used protocols in treating patients with proven cancer-associated retinopathy (CAR).There is no universally accepted treatment algorithm for CAR and visual prognosis is very poor. We describe a patient with CAR with dramatic improvement in vision after treatment with high doses of corticosteroids followed by plasma exchange (PLEX) and present results of a systematic literature review of treatment efficacy of previously used protocols in treating patients with proven CAR.We describe a 70-year-old man with CAR who demonstrated dramatic improvement in vision after treatment with high doses of systemic corticosteroids followed by 7 sessions of PLEX. We then report the results of a systematic review of all previously published English literature discussing visual outcomes of various treatment regimens used for patients with antibody-proven CAR.The index patient is a rare case of CAR with sustained significant improvement in vision after treatment with high doses of corticosteroids followed by PLEX. The systematic review identified 28 antibody-proven cases of CAR, 27 of which were treated with steroids, which resulted in varying degrees of improvement in visual acuity in 59% (16 of 27). The time from symptom onset to initiation of treatment and the dose of steroids did not influence the visual outcome. Three patients were also treated with PLEX in addition to steroids, and 2 of 3 patients demonstrated improvement in vision; however, there was no difference in visual outcome in patients treated with steroids only versus those treated with steroids + PLEX.Treatment with steroids or steroids + PLEX resulted in some improvements in visual acuity in 59% of patients. Removal of antirecoverin antibodies with PLEX can arrest the immune attack on the photoreceptors and potentially improve visual function; thus, it should be considered in addition to steroids. Further studies with larger cohorts are needed to establish a treatment protocol and further determine the effectiveness of the different approaches.The author(s) have no proprietary or commercial interest in any materials discussed in this article.