Main Session
Sep
30
QP 16 - Head and Neck 5: Quick Pitch: From Fraction to Function: Tailoring Head & Neck Radiotherapy
1091 - HYPCON 03 Pilot Study: A Study Exploring Delivery of 3Gy per Fraction in Post Operative Radiotherapy for Head and Neck Carcinomas
Presenter(s)
Aman Sharma, MD, DO, DSc - All India Institute of Medical Sciences, Healthcare, Practitioner and Technician, Delhi
A. Sharma1, A. Amariyil2, A. Ramadas3, A. Maiti1, K. Kamboj4, S. Mallick5, S. Panda6, J. Sharma1, N. Gupta1, R. Kumar6, S. Kumar7, A. Thakar8, and S. Bhasker4; 1National Cancer Institute, All India Institute of Medical Sciences, New Delhi, India, 2AIIMS New Delhi, New Delhi, Delhi, India, 3National Cancer Institute, AIIMS New Delhi, Delhi, India, 4All India Institute of Medical Sciences, New Delhi, India, 5National Cancer Institute, Jhajjar, Haryana, India, 6National Cancer Institute, AIIMS-Jhajjar, Jhajjar, India, 7All India Institute of Medical Sciences, New Delhi, Delhi, India, 8All India institute of Medical Sciences, New Delhi, India
Purpose/Objective(s):
Hypo-fractionation reduces treatment time and has potential to improve treatment outcomes by finishing delivery of PORT before accelerated repopulation sets in. The present study evaluated treatment compliance, acute morbidities, Ryles tube insertion during the course of RT and radiation treatment time (RTT) for HNC subjected of adjuvant hypo-fractionated radiotherapy.Materials/Methods:
The HYPCON-03 pilot study evaluated feasibility of 45Gy in 15 fractions over 3 weeks. Forty-six patients were enrolled in the study from May 2024 to November 2024. All patients were in intermediate risk group (margin positive disease & extracapsular excluded). Clinical target volume (CTV) included CTV_HR (primary tumor bed) & CTV_LN (regional lymphatics at risk). For well lateralised lesion & pN0 neck only ipsilateral regional lymphatics were included whereas for midline lesions or node positive disease bilateral lymphatics were irradiated. A 5mm margin generated the PTV. All critical adjoining organs & swallowing structures were delineated. Swallowing sparing double arc VMAT with 6 MV photons (dose rate 600MU/min) (Acuros-XB algorithm version 15.6.05) was delivered to all patients. Image guidance was done with onboard cone beam CBCT done for the first three fractions and then twice weekly. Compliance was defined as patients that were able to complete the stipulated course of RT course. RTT was calculated form date RT start to date of RT end. Acute toxicities were evaluated as per RTOOG criteria.Results:
Most of the patients in the study were oral cavity carcinomas 76%, majority of patents presented in stage IV (58.7%). Ipsilateral neck was irradiated in 37% of patients whereas 63% received PORT to bilateral neck. As regards to development of acute toxicities 26% of patients developed any grade 3 toxicities. Grade 3 pharyngitis was seen in 10.8% of patients, grade 3 mucositis in 15.2%, grade 3 dermatitis in 2%. None of patients developed = Grade 3 laryngeal/salivary toxicities & there were no grade 4/5 acute toxicities. Pre RT ryles tube was inserted in 8.7% (4/46) of patients where as 11.9% (5/42) of patients required Ryles tube insertion during the course of PORT. Adherence to hypo-fractionated PORT course was seen in 97.7%. Median RTT was 22 days (IQR 20 -24 days).Conclusion:
Hypo-fractionated PORT of 3Gy per fraction is associated with excellent treatment compliance (98%) & reduces radiation treatment time to 22 days. Nearly 1 out of every 4 patients developed any grade III toxicity. Delivery of 15 factions of PORT over 3 weeks is feasible, longer follow is required to confirm our findings. Our findings are particularly relevant to LMIC’s where cancer incidence has outnumbered the availability of resources.