Allen M Chen1, Jessica Meshman1, Sophia Hsu1, Taeko Yoshizaki1, Elliot Abemayor2, Maie St John2. 1. Department of Radiation Oncology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California. 2. Department of Otolaryngology - Head and Neck Surgery, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California.
Abstract
BACKGROUND: The purpose of this study was to present our findings on the use of limited-field, oropharynx-directed ipsilateral irradiation for p16-positive squamous cell carcinoma of unknown primary origin. METHODS: Between April 2011 and January 2016, 25 patients with a histological diagnosis of p16-positive squamous cell carcinoma were selectively irradiated to the ipsilateral oropharynx and cervical neck for tumors of unknown primary origin. The dose to the oropharynx ranged from 54-60 Gy (median 60 Gy) in 30-33 fractions. Concurrent cisplatin-based chemotherapy was administered to 8 patients (32%). RESULTS: The actuarial 2-year estimates of locoregional control, progression-free survival, and overall survival were 91%, 87%, and 92%, respectively. One patient failed in the contralateral neck. There was no grade 3 + toxicity in either the acute or late setting. CONCLUSION: Oropharynx-directed, ipsilateral radiation results in disease control that compares favorably with historical controls treated by comprehensive mucosal and bilateral neck radiation.
BACKGROUND: The purpose of this study was to present our findings on the use of limited-field, oropharynx-directed ipsilateral irradiation for p16-positive squamous cell carcinoma of unknown primary origin. METHODS: Between April 2011 and January 2016, 25 patients with a histological diagnosis of p16-positive squamous cell carcinoma were selectively irradiated to the ipsilateral oropharynx and cervical neck for tumors of unknown primary origin. The dose to the oropharynx ranged from 54-60 Gy (median 60 Gy) in 30-33 fractions. Concurrent cisplatin-based chemotherapy was administered to 8 patients (32%). RESULTS: The actuarial 2-year estimates of locoregional control, progression-free survival, and overall survival were 91%, 87%, and 92%, respectively. One patient failed in the contralateral neck. There was no grade 3 + toxicity in either the acute or late setting. CONCLUSION: Oropharynx-directed, ipsilateral radiation results in disease control that compares favorably with historical controls treated by comprehensive mucosal and bilateral neck radiation.