The FROST trial’s recruitment goal is 200 women, but only a handful of patients have been enrolled since recruitment began in December last year. Yet overall, Dr Holmes estimates that 60% of women diagnosed with mammogram, ultrasound, or MRI screening have stage I breast cancer, and might be suitable candidates for this approach.5
But, without randomized results and head-to-head comparisons to lumpectomy, some physicians say they prefer to stay with the known surgical approach, for now. Cryosurgery’s disadvantages, in general — not just in the breast— include missed microscopic disease, while surgery offers more cancer control.
There’s also a lack of long-term outcomes and too few patients, said Julio Pow-Sang, MD, chairman of genitourinary oncology at the Moffitt Cancer Center in Tampa, Florida.
At Moffitt, physicians use cryosurgery primarily for prostate cancer patients as salvage therapy, when other treatments fail, Dr Pow-Sang said, or as “focal therapy” if the cancer occurs on only one side of the gland.
But no clinical trials currently involve cryosurgery in the breast, according to an institute spokesman.
Similarly, at the National Institutes of Health (NIH)’s Center for Interventional Oncology in Bethesda, Maryland, Bradford Wood, MD, the center’s director, took a nuanced view of cryotherapy in the breast, acknowledging, however, that breast pathology is not his area of expertise.
Cryosurgery’s use in other organs appears more promising, Dr Wood said, though it’s just “one tool within an arsenal of tool kits for the minimally invasive, image-guided destruction of neoplasms.” Some involve heat instead of cold.
Most promising, however, and under intense investigation, are therapies combining cryosurgery and other ablative techniques with immunotherapy — specifically checkpoint inhibitors, according to Dr Wood.
“Immunotherapy has changed the whole paradigm,” for treating cancer, Dr Wood said. Research suggests in the liver, for example, that combining cryoablation with chemotherapy and checkpoint inhibitors may “release a storm of cytokines” a highly desirable systemic effect, which enhances checkpoint inhibitors’ effectiveness.6
“This is an emerging early direction for cryoablation for investigators,” he said. “If it takes off, we may be able to vaccinate with ablation.”
Meanwhile, as for cryosurgery’s future in breast cancer, Dr Holmes acknowledged the scarcity of long-term results. But in Japan, where more than 200 patients have been followed for at least a decade, he said, recurrence rates are low. Nor is he discouraged by the tentative embrace by some in the medical community.
“It took 80 years for radical mastectomy to fall out of favor,” Dr Holmes said. “The medical community has always been slow to adopt to new therapies.”
- Simmons RM, Ballman KV, Cox C, et al. A phase II trial exploring the success of cryoablation therapy in the treatment of breast carcinoma: results from ACOSOG (Alliance) Z1072. Ann Surg Oncol. 2016;23(8):2438-45. doi: 10.1245/s10434-016-5275-3
- FROST clinical study. Sanarus website. http://www.sanarus.com/clinical-info/frost-clinical-study. Accessed May 2017.
- Sanarus V2 Treatment System premarket submission. US Food and Drug Administration website. https://www.accessdata.fda.gov/cdrh_docs/pdf6/K062896.pdf. Accessed May 2017.
- Cryosurgery in cancer treatment. National Cancer Institute website. https://www.cancer.gov/about-cancer/treatment/types/surgery/cryosurgery-fact-sheet. Accessed May 2017.
- Cancer facts & figured 2015. American Cancer Society website. https://www.cancer.org/research/cancer-facts-statistics/all-cancer-facts-figures/cancer-facts-figures-2015.html. Accessed May 2017.
- Duffy AG, Ulahannan SV, Makorova-Rusher O, et al. Tremelimumab in combination with ablation in patients with advanced hepatocellular carcinoma. J Hepatol. 2017;66(3):545-51. doi: 10.1016/j.jhep.2016.10.029