Oligometastatic head and neck cancer: Navigating patient trajectories and broader implications

Oligometastatic head and neck squamous cell carcinoma is a distinct clinical state inadequately addressed in current metastatic disease trials. This narrative review is based on historical literature and recently published data of the Omet trial. The Gortec 2014-04 Omet phase II randomized trial investigated whether genuine metachronous oligometastases in head and neck squamous cell carcinoma, characterized by a limited number (up to three) of lesions not induced by prior systemic therapy, may benefit from a “de-escalation strategy” using curative-intent stereotactic ablative radiotherapy alone rather than strategies relying on systemic treatments upfront. Randomized phase II-III trials are scarce on head and neck squamous cell carcinoma. In the Omet trial, survival at 1 year exceeded 85 % in both arms. Progression-free survival was, as anticipated, slightly longer in the group chemotherapy and stereotactic ablative radiotherapy (10 months versus 7.5 months) but without deleterious impact upon metastatic relapse. Stereotactic ablative radiotherapy alone showed significantly lower grade 3–4 toxicity (8.8 % versus 60 %). Quality of life declined less with stereotactic ablative radiotherapy alone. Poor prognostic factors included male sex and multiple metastases. Major protocol deviations correlated with worse outcomes. Stereotactic ablative radiotherapy offers a viable, less toxic alternative to systemic therapy for genuine oligometastatic head and neck squamous cell carcinoma, warranting refined patient selection and further research. Despite its role as a new standard-of-care, the role of immunotherapy remains uncertain in the oligometastatic setting and requires specific studies in oligometastatic head and neck squamous cell carcinoma to challenge this new option.