Overlap of Afferent Baroreflex Failure and Lower Cranial Neuropathies in Long-term Oropharyngeal Cancer Survivors Postradiation Therapy: Secondary Analysis of a Prospective Registry Cohort.

Purpose: Afferent baroreflex failure (ABF) is an underrecognized late complication of radiation therapy (RT) in oropharyngeal cancer (OPC) survivors. Patients with ABF present with labile blood pressure, palpitations, lightheadedness, and syncope. ABF is attributed to fibrotic injury of the carotid sinus nerve and shares pathophysiology with lower cranial neuropathies (LCNP), which are routinely screened as part of head and neck physical examination in OPC survivorship. We evaluated the prevalence of ABF in patients with LCNPs and prior history of OPC treated with RT. Methods and Materials: This is a secondary analysis of a prospective cohort of OPC survivors treated with RT at a tertiary cancer center (2016-2019). ABF manifestations included new or worsening hypertension, hypotension requiring intervention, arrhythmias, or syncope. LCNP was defined as motor signs of neuropathy of the glossopharyngeal, vagus, or hypoglossal cranial nerves ≥3 months after therapy documented in the electronic health record. Results: Among 414 patients, 87% were men and 91% white with a median age of 60 (54-67) years at cancer diagnosis. During a median follow-up of 6.3 years (Interquartile range, 5.2-7), LCNP was diagnosed in 23 patients (5.8%). ABF manifestations were reported in 82 patients (19.6%) in the whole cohort (labile hypertension in 9.2%, hypotension in 7%, arrhythmias in 3.9%, syncope in 3.9%). ABF manifestations were present among 39% of patients with LCNP compared with 18.3% without LCNP (OR = 2.93; 95% CI, 1.22-7.06; Conclusions: In this cohort of long-term OPC survivors treated with RT, over one-third of patients with LCNP had manifestations linked to ABF. A low threshold for dedicated ABF evaluation may be warranted in this high-risk subgroup.