Open AccessOutcomes after primary intensity‐modulated radiation therapy for oropharyngeal squamous cell carcinoma at a New Zealand regional cancer centre: Impact of p16 status
Author(s) -
Maqsood Saad,
Jameson Michael B.,
De Groot Charles,
Hartopeanu Cristian,
Yasin Nur Azri Bin Haji Mohd,
Thotathil Ziad
Publication year - 2018
Publication title -
cancer reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.261
H-Index - 5
ISSN - 2573-8348
DOI - 10.1002/cnr2.1001
Subject(s) - medicine , radiation therapy , oncology , chemotherapy , cancer , stage (stratigraphy) , head and neck cancer , retrospective cohort study , paleontology , biology
The rising incidence of oropharyngeal squamous cell carcinoma (OPSCC) in New Zealand is due to an increase in the numbers of human papilloma virus (HPV)–associated OPSCC. We evaluated the impact of positive p16 immunohistochemistry, as a surrogate for HPV positivity, on OPSCC outcomes after primary intensity‐modulated radiotherapy (IMRT) with or without concurrent chemotherapy. Methods Retrospective review was undertaken of electronic medical records of 90 patients with OPSCC who received primary IMRT with or without chemotherapy between 2008 and mid‐2015 at the Regional Cancer Centre, Waikato Hospital, Hamilton, New Zealand. Results Median age was 57.5 years. Immunohistochemistry for p16 was positive in 53 (59%) OPSCC while 37 (41%) had negative or unknown p16 status. Median radiotherapy dose was 70 Gy. Chemotherapy was administered to 78 (87%) patients, most receiving high‐dose cisplatin. Nine patients had residual disease following treatment completion. Seven patients relapsed, and 26 died during the study period. Five patients with p16‐positive OPSCC had persistent or recurrent disease. Actuarial 3‐year locoregional control, disease‐free survival, and overall survival for all patients were 80.7%, 74.7%, and 77.1%, respectively. Among p16‐positive OPSCC patients, 3‐year locoregional control, disease‐free survival, and overall survival were 89.5%, 80.8%, and 90.9%, respectively. Conclusion Outcomes after IMRT for OPSCC at Waikato Hospital are in line with the reported literature. Human papilloma virus–related OPSCC has better outcomes compared with patients with unknown or HPV‐unrelated OPSCC. Trials are underway evaluating reduced intensity of treatment for HPV‐related OPSCC.