Severance Hospital researchers have found that 15 separate sessions of volumetric modulated arc therapies (VMAT) can significantly reduce complications for breast cancer patients who have undergone breast mastectomy and reconstruction surgery.
About 50 percent of breast cancer patients who had breast reconstruction have so far experienced complications during the course of radiation therapy, such as rigid and thickening of the surrounding tissue, tissue necrosis, and infection. In some severe cases, the patients had to give up their breast reconstruction.
|From left, Professors Kim Yong-bae, Jang Ji-seok, Lee Dong-won and Song Seung-yong|
“Although the radiation beam is a straight line, the breast is a curve, and the size, shape, and angle of the breast are different for each patient,” Severance said. “This limits the ability to shoot a uniform dose of radiation.”
To solve such limitations, the team, led by Professors Kim Yong-bae, Jang Ji-seok, Lee Dong-won and Song Seung-yong at the hospital, analyzed the breast reconstruction complications and prognosis of 75 breast cancer patients treated from January 2012 to December 2016.
The researchers removed the patients’ breasts and primarily expanded the scar tissue using a tissue expander. Afterward, the team shaped the patient’s breasts in the form of water droplets and gave them 15 separate VMAT sessions in the course of three weeks. After six months, the team removed the tissue expander and inserted a prosthetic breast implant.
Follow-up of 75 patients revealed only 14.3 percent of the patients who underwent VMAT therapy showed side effects compared to the 38.5 percent of patients who showed breast reconstructive side effects in conventional radiotherapy.
The follow-up of the reconstruction complications and prognosis of 75 patients showed that the complication risk increased by 12 percent with an increased radiation dose of 1 gray (Gy) and showed a significant correlation between complications of breast reconstruction and radiation dose.
“An indirect comparison with other studies also showed that 15 separate sessions of VMAT therapy had similar complications as those without radiation therapy,” Professor Kim said.
Frontiers in Oncology published the study in its April edition.