Evaluation of risk-tailored individualized selection of radiation therapy target volume for head and neck carcinoma of unknown primary. (October 2022)

• Record Type: Journal Article
• Authors: Ghatasheh, Hamza; Huang, Shao Hui; Su, Jie; Xu, Wei; Bratman, Scott V.; Cho, John; Giuliani, Meredith; Hahn, Ezra; Hope, Andrew; Kim, John; O'Sullivan, Brian; Ringash, Jolie; Waldron, John; Chepeha, Douglas B.; Irish, Jonathan C.; Goldstein, David P.; Spreafico, Anna; Tong, Li; de Almeida, John R.; Hosni, Ali
• Is Part Of: Radiotherapy and oncology. Volume 175(2022)
• Page Start: 56
• Page End: 64
• Publication Date: 2022-10
• Subjects: Head and neck cancer -- Unknown primary -- Radiation therapy -- Volume de-escalation -- Outcomes -- IMRT; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2022.07.016
• Languages: English
• ISSNs: 0167-8140

Abstract

Highlights: Accurate prediction of hidden disease site is critical to allow RT volume de-escalation for HNCUP. Risk-stratified RT volume de-escalation resulted in favorable outcomes. Concurrent chemotherapy was associated with better DFS and OS in cN2-3 HNCUP. Abstract: Purpose: Intensity-modulated radiation therapy (IMRT) has enabled risk-tailored approach to elective mucosal and nodal clinical target volumes (CTVs) in treatment of head and neck carcinoma of unknown primary (HNCUP). This study report outcomes following such approach. Methods: HNCUP patients treated with definitive IMRT between 2005 and 2018 were reviewed. Local failure (LF), regional failure (RF), distant metastasis (DM), overall survival (OS) and grade ≥3 late toxicity (LT) were analyzed. Multivariable analysis (MVA) was used to identify OS predictors for entire cohort and cN2-3 subgroup. Results: A total of 203 patients were eligible: cN1 (7%), cN2a (14%), cN2b (46%), cN2c (14%) and cN3 (19%). Among 118 patients with known HPV status (by p16 staining), 81 (68%) were positive. IMRT target volume spared contralateral tonsil (55%), bilateral or contralateral sides of hypopharynx (72%), nasopharynx (72%), larynx (87%) and contralateral uninvolved neck (21%). Median follow-up was 5 years. Five-year LF, RF, DM, OS, and LT were 3%, 14%, 10%, 79%, and 7% respectively. Four patients developed mucosal recurrence: 3 within and 1 at the margin of the elective mucosal CTV. None of ipsilateral neck irradiation patients failed in the contralateral uninvolved neck. MVA identified cN2c-N3, HPV-negative status and older age as predictors for inferior OS. Within cN2-3 subgroup (n = 189): cN2c-N3, HPV-negative status and older age predicted lower OS, while concurrent chemotherapy was associated with better OS. Conclusion: Definitive IMRT with risk-adaptive radiation volume de-escalation for HNCUP resulted in high probability of tumor control with acceptable rate of late toxicity.