PQA 04 - Breast Cancer, Patient Reported Outcomes/QoL/Survivorship, Functional Radiation Medicine, Hematologic Malignancies, Palliative Care, and International/Global Oncology
Presenter(s)
V. Shankar1, S. Ghosh2, H. S. Vangipuram3, D. Arjundas4, S. Paramasivan5, S. Cholayil6, and V. R. Anand7; 1Division of Radiosurgery, Apollo Cancer Centers, Chennai, India, 2Dept. of Neurosurgery, Apollo Proton Cancer Center, Chennai, India, 3Department of Undergradute Education, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India, 4Chief Neurologist, Mercury Hospital, Chennai, India, 5Dept. of Neurosurgery, Apollo Hospitals, Greams Unit, Chennai, India, 6Apollo Cancer Centers, Chennai, India, 7Sai Neuro Hospital, Chennai, India
Purpose/Objective(s):
Outcomes after stereotactic radiosurgery (SRS) for trigeminal neuralgia (TN) are commonly summarized using coarse ordinal scales that do not distinguish neuromodulatory benefit from destructive sensory injury, limiting phenotypic resolution. We aimed to develop and preliminarily validate the Trigeminal Neuralgia Radiosurgery Neuromodulation Score (TN-RNS), a domain-based composite outcome instrument characterizing the balance between pain relief and sensory cost after SRS for primary TN.
Materials/Methods:
We performed a retrospective validation study using a prospectively maintained radiosurgery database (2005–2025). Of 478 patients treated with SRS, 418 with primary TN undergoing first-time CyberKnife SRS were identified; 355 with complete domain-level documentation comprised the validation cohort (median follow-up 60 months). TN-RNS independently scores paroxysmal burden, triggerability, background dysesthesia, and sensory change on 0–4 ordinal scales (composite 0–16; lower scores indicate more favorable neuromodulation). Scores were abstracted longitudinally alongside Barrow Neurological Institute (BNI) pain and numbness grades. Psychometric evaluation included inter-rater reliability, internal consistency, construct validity, and responsiveness using standardized response means and mixed-effects modeling.
Results:
Median age was 62 years and median disease duration 6 years; 68% had BNI pain grades IV–V despite optimized medication. Inter-rater agreement was substantial to almost perfect (? = 0.75–0.82), with excellent composite reliability (ICC = 0.90) and good internal consistency (Cronbach’s a = 0.81). Pain-related domains correlated strongly with BNI pain grades and the sensory domain with BNI numbness, while cross-domain correlations were modest, supporting discriminant validity. Root entry zone targeting and higher prescription doses were associated with greater paroxysmal reduction but higher sensory change, demonstrating a dose- and target-dependent trade-off. Median composite TN-RNS improved from 11 at baseline to 4 by 12 months (standardized response mean 1.10), with sustained benefit on longitudinal modeling over extended follow-up and greatest responsiveness in paroxysmal and triggerability domains. TN-RNS identified neuromodulatory success (61%), destructive success (18%), and mixed response (21%), despite 78% meeting conventional BNI criteria for a “good” outcome.
Conclusion:
TN-RNS is a practical, reliable, and responsive domain-based outcome instrument that complements BNI scales by delineating multidimensional radiosurgical effects in primary TN. By explicitly capturing neuromodulatory benefit and sensory cost, TN-RNS supports refined outcome assessment, patient counseling, and biologically informed dose–target strategies, while enabling phenotypic stratification beyond conventional pain metrics. Prospective multicenter validation is warranted.
