Delayed Gemcitabine-Induced Posterior Reversible Encephalopathy Syndrome.

INTRODUCTION: Posterior reversible encephalopathy syndrome (PRES) is a rare clinical-radiographic syndrome that has been expanding rapidly in the world of clinical medical oncology and hematology. In this article, we provide a unique patient case of delayed gemcitabine-induced PRES. BRIEF CASE REPORT: A 60-year-old African American female with significant past medical history of ER+/PR+/HER2- invasive ductal carcinoma of the left breast is seen in the medical oncology clinic with vague, mild complaints of lightheadedness. She had progressed on multiple lines of chemotherapy and was ultimately switched to gemcitabine. One month after her third dose of gemcitabine, she developed acute vision loss and soon developed generalized tonic-clonic seizure. Extensive workup was unrevealing other than PRES and she slowly improved with supportive care and withdrawal of the medication. DISCUSSION: Multiple case reports have described PRES in the context of combination chemotherapy with gemcitabine and a platinum agent in the treatment of gastrointestinal malignancies. With growing evidence, this case is consistent with the hypothesis that gemcitabine as monotherapy has a direct association with PRES. This case highlights a unique aspect in that PRES can occur at a delayed time interval, much further than the expected hours to days after the previous treatment.