Synchronous versus asynchronous delivery of concurrent chemotherapy and radiation for head and neck cancer: Does timing matter?

Abstract

Purpose

To evaluate the impact of variations in the timing of chemotherapy and radiation on clinical outcome for patients treated with concurrent chemoradiation for head and neck cancer.

Methods and materials

The medical records of 264 consecutive adult patients treated with concurrent cisplatin-based chemoradiation for squamous cell carcinoma of the head and neck were reviewed. Among these 187 patients (71 %) had chemotherapy and radiation commencing on the same day (“synchronous delivery”) and 87 patients had chemotherapy and radiation commencing on different days (“asynchronous delivery”).

Results

The 3-year actuarial estimates of overall survival (74 % vs. 76 %), progression-free survival (75 % vs. 75 %), and local-regional control (71 % vs. 73 %) were not significantly different between concurrent chemoradiation patients treated by synchronous and asynchronous delivery methods, respectively (p > 0.05, for all). Exploratory subset analysis using the 1, 3, 7, 10, and 14 day cutoffs as thresholds for starting chemotherapy and radiation together demonstrated that patients who had greater than a 7 day gap between chemotherapy and radiation had significantly worse 3-year overall survival (63 % vs. 78 %, p = 0.01), progression-free survival (59 % vs. 77 %, p = 0.01), and local-regional control (65 % vs. 74 %, p = 0.02) compared to those whose treatment commencement occurred within 7 days, respectively.

Conclusion

While the clinical repercussions of not starting concurrent chemotherapy and radiation on the same day are likely of minimal consequence for patients with head and neck cancer, efforts to start treatments within 7 days of one another are recommended.