Delayed Onset ICANS Leading to Bilateral Cranial Neuropathies: Two Case Reports
Kelsey Beck1, Shemonti Hasan2, Shyamal Mehta2, Cristina Valencia Sanchez2
1Mayo Clinic Alix School of Medicine, 2Mayo Clinic Arizona, Department of Neurology
Objective:
To describe two cases of bilateral facial nerve neuropathy from late onset immune effector cell-associated neurotoxicity syndrome (ICANS) after chimeric antigen receptor T-cell (CAR-T) therapy for treatment of Multiple Myeloma.
Background:
ICANS is a complication of CAR-T therapy which typically occurs within the first week of treatment. Manifestations can include encephalopathy with confusion and behavioral changes, headache, agraphia, tremors, seizures, cerebral edema, or death. Isolated cranial neuropathies, particularly after this period, have not been reported.
Results:
Two patients, a 69-year-old male (case 1) and a 67-year-old female (case 2), presented with facial nerve palsy 3 weeks (20 and 21 days respectively) after CAR-T therapy for multiple myeloma. Neither of the patients had developed symptoms of neurotoxicity immediately after CAR-T treatment. Case 1 experienced gradual onset of decreased taste, facial numbness, inability to smile or move his eyebrows, and drooling. Exam showed bilateral facial weakness in a lower motor neuron pattern, worse on the left as compared to the right. Case 2 experienced right-sided facial droop with inability to move her right eyebrow or symmetrically smile, right ear fullness, and right-sided drooling. Exam revealed right-sided facial weakness in a lower motor neuron pattern. MRI of the brain in both patients demonstrated bilateral contrast enhancement of the facial nerves. Cerebrospinal fluid analysis in case 1 showed mildly elevated protein (67 mg/dL), with negative infectious studies, and no evidence of malignancy. Case 2 did not have lumbar puncture, but respiratory viral and bacterial pathogen panel was negative. Both patients were treated with a short course of oral dexamethasone with complete resolution in case 1, and partial improvement of symptoms in case 2.
Conclusions:
Delayed ICANS should be considered in CAR-T patients presenting with isolated cranial neuropathies after ruling out infection and malignancy. Treatment with steroids can lead to recovery.