Treatment Deescalation Strategies for Nasopharyngeal Cancer

Importance

Since the advent of modern radiotherapy techniques and incorporation of systemic chemotherapy for nasopharyngeal cancer, locoregional control has been excellent. However, the rate of treatment-related complications, many of which are irreversible, remains high. New approaches are being explored to determine whether the toxic effects of treatment can be relieved while maintaining disease control. This review presents the current state of deescalation strategies for nasopharyngeal cancer.

Observations

A review of the literature shows that deescalation approaches can be generally categorized into deescalating systemic therapy vs deescalating radiotherapy. This review discusses studies that have explored sparing chemotherapy in selected patients with stage II cancer as well as altering the chemotherapy scheduling, dosing, and agent from the current standard of care, cisplatin. Deescalating radiotherapy has involved decreasing the dose and the treatment volume. In many cases, these approaches are being guided by measuring Epstein-Barr virus DNA levels, which is a robust biomarker for screening, treatment monitoring, and surveillance. Ongoing work with various imaging modalities, such as fluorodeoxyglucose positron emission tomography and dynamic contrast-enhanced or diffusion-weighted magnetic resonance imaging sequences, have shown promise as another biomarker to safely guide practitioners toward deescalation.

Conclusions and Relevance

Various strategies to deescalate treatment in nasopharyngeal cancer have been explored, and outcomes have remained excellent in most approaches. Patient selection remains key, and long-term outcomes and late complications are still to be determined. Continued investigation with prospective, multi-institutional studies are needed to better elucidate how treatment for nasopharyngeal carcinoma can best be individualized and deescalated.