Early PET/CT response after first‑line pembrolizumab in recurrent or metastatic head and neck cancer

Prospective Observational Study On The Impact Of Early Response To First-line Anti-PD-1 Therapy In Patients With Recurrent And/Or Metastatic (R/M) Head And Neck Squamous Cell Carcinoma, Assessed By 18F-FDG PET/CT

University of Rome Tor Vergata · NCT07448727

This project will see if an 18F‑FDG PET/CT scan after two doses of pembrolizumab can tell who is responding among patients with recurrent or metastatic PD‑L1 CPS ≥1 head and neck cancer.

Quick facts

Study typeObservational
Enrollment25 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Rome Tor Vergata (other)
Drugs / interventionspembrolizumab
Locations1 site (Rome, Italy)
Trial IDNCT07448727 on ClinicalTrials.gov

What this trial studies

This observational study follows patients with recurrent or metastatic head and neck squamous cell carcinoma and PD‑L1 CPS ≥1 who receive two administrations of pembrolizumab as first‑line monotherapy. An 18F‑FDG PET/CT is done at baseline (within 30 days before treatment) and again after two cycles (about 6 weeks) to measure changes in tumor FDG uptake. Responders are defined as complete resolution of FDG uptake in target lesions or a ≥30% decrease in target tumor FDG SULpeak, while progressive disease is a ≥30% increase in SULpeak or new FDG‑avid lesions. Any subsequent treatment changes are made by the treating physician according to routine clinical practice.

Who should consider this trial

Good fit: Ideal candidates are adults with histologically confirmed recurrent or metastatic HNSCC not amenable to curative local therapy, eligible for first‑line pembrolizumab monotherapy, and with PD‑L1 CPS ≥1 who can undergo PET/CT imaging.

Not a fit: Patients with PD‑L1 CPS <1, contraindications to immune checkpoint inhibitors, or those unable to have the required PET/CT scans are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, the approach could identify responders early so clinicians can continue effective therapy or switch nonresponders sooner to other options.

How similar studies have performed: Prior small and exploratory studies have suggested that early PET/CT changes can correlate with immunotherapy outcomes, but findings are mixed and the approach is not yet standard practice.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Histological diagnosis of recurrent and/or metastatic HNSCC, not amenable for curative locoregional treatment (either surgery or radiotherapy), and amenable for first line systemic treatment
* CPS PD-L1 \>=1

Exclusion Criteria:

* Any controindication to immune checkpoint inhibitors

Where this trial is running

Rome, Italy

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Head & Neck Cancer, Head & Neck Squamous Cell Carcinoma

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.