Pancerebellitis Under Immunotherapy With Pembrolizumab

Figure

Cranial magnetic resonance imaging in a 52-year-old male patient with pulmonary adenocarcinoma revealed new signal hyperintensities diffusely distributed over the cerebellum with spots of enhancement (arrow) without a space-occupying effect (Figure). At the time of imaging, the patient had been receiving immunotherapy with the PD-1 inhibitor pembrolizumab for 8 months. The patient suffered from ataxia. The patient reported having no headaches, double vision, or vomiting. Thus, based on radiology and symptoms, pancerebellitis was suspected. This is a very rare disorder that can occur due to infection, in the context of a neoplasm, and as an autoimmune-mediated side effect of an immune checkpoint inhibitor. To date, only isolated cases have been described in conjunction with checkpoint inhibitors. Differential diagnoses were excluded by means of lumbar puncture (physiological cell count, no evidence of malignant cells and antibodies) and serum chemistry (normal inflammatory parameters, no antibodies detected). The patient received high-dose glucocorticoid treatment over a 5-day period. This treatment resulted in symptom improvement. Cerebellitis has not been included as yet in the product information for pembrolizumab.

Dr. med. Myriam Koch, Prof. Dr. med. Janine Rennert, Prof. Dr. med. Christian Schulz
Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg (Koch, Schulz), [e-mail]
Institut für Röntgendiagnostik, Universitätsklinikum Regensburg Institut (Rennert)

Conflict of interest statement: The authors declare that no conflict of interest exists.

Translated from the original German by Christine Rye.

Cite this as: Koch M, Rennert J, Schulz C: Pancerebellitis under immunotherapy with pembrolizumab. Dtsch Arztebl Int 2022; 119: 820b. DOI: 10.3238/arztebl.m2022.0228