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Using radiation-emitting capsules to treat cervical cancer

Brachytherapy involves putting radiation-emitting capsules inside tumors to spare surrounding tissues. Researchers found that it successfully increases the overall survival rate for patients with cervical cancer that has not spread.


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Image Credit: Brachytherapy via Flickr

Brachytherapy is a type of radiation therapy used to treat cancer, where small capsules containing a radiation source are placed inside the body, in or near a tumor. It allows doctors to focus on specific areas inside the body and deliver a high and concentrated dosage of   radiation. This is different from external radiation therapy, where doses of radiation are delivered from beams that originate outside of the body and treat large areas. 

Brachytherapy treatments are usually shorter than other cancer treatments (one or two sessions a day over a course of a few days or weeks), which is a plus when it comes to cancer, since some cancers spread and worsen fast. For quickly progressing cancers, such as cervical cancer, quick action can save a patient’s life.

Brachytherapy is part of the “standard of care,” or the recommended treatment plan for locally advanced cervical cancer, as recommended by the National Comprehensive Cancer Network. However, the use of brachytherapy has been declining from 83% in 1988 to 43% in 2003 due to increasing popularity of external beam radiotherapy. However, brachytherapy does still increase overall survival rates for cervical cancer patients. 

Recently a group of physician-scientists within the University of California system completed a study to answer two questions. First, they asked how many cervical cancer patients receive the recommended standard treatment. Second they wondered if there was an association between receiving brachytherapy and completing care within eight weeks with survival. The standard treatment defined included external beam radiation therapy, chemotherapy, and brachytherapy, all completed within 8 weeks.

Historical data from the National Cancer Database were collected from across multiple hospitals to answer the study questions. They collected medical records from the years 2004 to 2015 for 10,172  patients between the ages of 18 and 79 who were diagnosed with cancer in the cervix only, which means that the cancer has not spread to other parts of the body.

To study the treatment, the patients were divided into four groups based on the treatment they had received. One group received an 8-week course of brachytherapy and one received a longer course. While the other two groups received no  brachytherapy, one of them received an 8-week course and the other received a longer course. Different characteristics such as race, age, sex, and income were also studied.

The medical dataset showed that 59.5% of the 10,172 patients received brachytherapy. Among that group, 29.3% finished treatment within 8 weeks while 30.3% had a longer course. The other 40.6% of the 10,172 patients did not receive brachytherapy, but 23.6% finished treatment within 8 weeks and 17% took longer.

Patients who had received brachytherapy within 8 weeks survived 131 months (about 10 years) after the diagnosis. This was higher than patients who had the longer brachytherapy course, who survived 95.5 months (about 8 years) after diagnosis. Patients whose treatment protocol did not include brachytherapy survived 78 months (6 years) if treatment took 8 weeks and 49 months (4 years) if it took more than 8 weeks.

Unsurprisingly, overall survival decreases if the cervical cancer is more advanced. Non-Hispanic black races are less likely to receive standard of care treatment. Low income and no health insurance were also associated with inadequate or no treatment. However, the researchers speculated from the data that living in urban areas may improve access to treatment, leading to a higher survival rate for these groups.

In conclusion, it was shown that brachytherapy was associated with a higher overall survival rate compared to the other forms of treatment mentioned before. Completing treatment in 8-weeks, regardless of what it was, was also associated with better survival. It is not known if shorter treatments cause better survival or if it just means that the patients who receive shorter treatments had another characteristic in common that caused better survival. 

This study shows that there is an immediate need to improve training and maintenance of brachytherapy skills so more patients have access to brachytherapy as part of standard care, rather than no care or ineffective care. The authors state that cancer patients will also benefit if more resources are available for those with cancer, especially those in groups shown to have lower survival, such as low-income patients and those without insurance. This will help ensure that the disadvantaged groups identified in this study receive standard treatment and therefore have a greater chance of survival. 

Study Information

Original study: Better late than never: Brachytherapy is more important than timing in treatment of locally advanced cervical cancer

Study was published on: 3 December 2021

Study author(s): Travis-Riley K. Korenaga, Emi J.Yoshida, Will Pierson, Jenny Chang, Argyrios Ziogas, Megan L.Swanson, Jocelyn S.Chapman, Sumi Sinha, and Lee-may Chenc

The study was done at: University of California (USA)

The study was funded by: Unknown

Raw data availability: Unknown

Featured image credit: Brachytherapy via Flickr

This summary was edited by: Gina Misra