Study Explores Immunotherapy Combination for Metastatic Cervical Cancer

Metastatic cervical cancer occurs when cervical cancer spreads beyond the cervix to other parts of the body, such as the lungs or liver. 

Moffitt Cancer Center experts, including Kamran Ahmed, MD, a radiation oncologist and principal investigator of the study, launched a trial evaluating the combination of stereotactic body radiation therapy (SBRT) and atezolizumab, an immunotherapy drug, for patients with advanced cervical cancer.  

New Treatment Strategy

Kamran Ahmed, MD

Sterotactic body radiation therapy is a technique in which a carefully programmed system of coordinates is used to deliver narrowly focused, high-dose radiation beams to a solid tumor. As with other types of radiation therapy, the goal of stereotactic body radiation therapy is to prevent tumor growth and ultimately shrink a tumor by damaging the DNA of the cancerous cells. 

The study enrolled 21 patients from Moffitt and Ohio State University. Patients were eligible if they had metastatic, recurrent or persistent cervical cancer with at least two tumor sites.  

Most patients enrolled had adenocarcinoma, and 71% had tumors that were PD-L1 negative, a tumor marker that signals response to anti-PD-1 therapy. 

Patients were followed for an average of about 45 months. First, they received stereotactic body radiation to at least one metastatic site, followed by atezolizumab.  

A Promising Approach  

Overall, 24% of patients experienced partial tumor shrinkage, while 57% had stable disease, meaning their cancer did not significantly grow or shrink. Among patients who responded to treatment, the response lasted an average of 8.6 months.

Researchers also found that patients with PD-L1-negative tumors still responded to treatment. 

“Currently, in the U.S., approval for anti-PD-1 therapy for patients with metastatic cervical cancer is only for those who have PD-L1-positive tumors, but in this study, we found that there were responses in patients regardless of whether they were PD-L1 positive or negative,” Ahmed said. 

Additionally, 38% of patients had a response in tumor lesions that were not directly treated with radiation, meeting the study endpoint for success.  

“Potentially, this study could open avenues for patients to be treated with immunotherapy who are not PD-L1 positive with metastatic cervical cancer,” Ahmed said. “It also shows us the potential of combining focal radiation therapy with immunotherapy for other tumor types that are not responsive to immunotherapy alone.”