Carbon Dioxide-Based Cancer Cryoablation Probe for Low-Resource Regions

Undergraduate researchers at John Hopkins University have developed a cryoablation probe for breast cancer, which uses carbon dioxide instead of argon, making it more affordable and accessible for use in low resource regions.

Treatments for women with breast cancer are scarce in poorer places. In fact, survival rates can be as low as 12% for breast cancer patients in places such as The Gambia, compared with 90% in the United States. Treatments that are commonly used in wealthier countries, such as surgery or chemotherapy, are either too expensive or impractical in poorer and more remote regions, where women frequently have to travel long distances to find a regional hospital that can offer help.

There is a clear need for an inexpensive solution, which can be applied in local clinics in such regions. To address this, a group of undergraduate researchers set out to adapt an existing cancer treatment, cryotherapy, to make it more suitable for a low resource context. Cryoablation does not require a sterile surgical suite or anesthesia, meaning that it would be suitable for use in local clinics, but traditional cryoablation can be very expensive, often costing upward of $10,000 for one treatment. Moreover, it typically requires a source of argon gas, which is difficult to find in low-resource areas.

The John Hopkins researchers turned to a readily available and inexpensive gas to power their new cryoablation system. Carbon dioxide is widely available, as it is used in carbonated soft drinks and as a cheap way of keeping things frozen worldwide. “When we started the project, experts in the area told us it was impossible to ablate meaningful tissue volumes with carbon dioxide,” said Nicholas Durr, a researcher involved in the project. “This mindset may have come from both the momentum of the field and also from not thinking about the importance of driving down the cost of this treatment.”

The researchers tested their carbon dioxide-powered cryoablation device in rats with mammary tumors, and found that it could kill a minimum of 85% of the tumor tissue, suggesting that it has significant potential in treating human breast cancers. While these initial results are promising, the device will need to be optimized further before it can proceed to clinical use.