Cancer therapy
raises hope

A Kuakini study shows women
do surprisingly well after breast
lump surgery and radiation

Kuakini Medical Center has attracted international interest with a study showing remarkably low recurrence of cancer and high survival rates after breast lumpectomy and radiation for 896 women, findings possibly related to Japanese ethnicity.

Three-fourths of the patients were Japanese. All had first-stage breast cancer and were treated at Kuakini with local incision of a tumor followed by radiation between January 1990 and December 2001.

Dr. Mark Kanemori, Kuakini radiation oncologist, oncology committee chair and lead author of the study, said Kuakini Medical Center has the best results reported in medical literature for so-called breast conservation therapy, which involves removing the tumor while preserving the breast.

Only six, or 0.67 percent, of the patients experienced recurrence of the same type of cancer in the same breast in the first six years after treatment, Kanemori said. Twelve others developed second breast cancers that were in different parts of the breast or were different types than the initial cancer.

"This is an amazingly low number," Kanemori said. "It is the lowest ever reported in the medical literature."

According to published medical accounts, he said, chances of the same cancer recurring in the same breast range from 2 to 16 percent within five years after lumpectomy and radiation.

Kanemori and Maria Prygrocki, with Kuakini's Oncology Data Registry, did the study primarily to assess the results of early detection and treatment of patients with breast conservation therapy. None had cancer spreading to other organs.

They also compared Kuakini's five-year breast cancer survival rates with national rates and "overall our survival rates were superior," Kanemori said.

The study reports a 90 percent five-year breast cancer survival rate at Kuakini Medical Center from 1992 to 1997 compared with 86 percent reported by the national Surveillance, Epidemiology and End Results Program.

"These remarkable findings are consistent with data here and in Japan reporting superior outcomes in Japanese patients with breast cancer compared to other ethnic groups," Kanemori said.

Hawaii State Tumor Registry data also show the Japanese have the lowest breast cancer mortality compared to other ethnic groups, Kanemori said.

He credits Kuakini's oncology team of physicians, nurses and therapists for the "excellent results" of breast conservation therapy there.

Kanemori said he and Prygrocki looked at the patient population, treatments, environmental conditions and other factors that might explain the low recurrence rates. He believes one answer is Kuakini's "outstanding" surgery.

He attributes much of the success of Kuakini's breast cancer program to Dr. Robert Oishi, who started the Kuakini Oncology Data Registry in 1965 and was the surgeon involved with the largest number of patients in the study.

The study was published in the May issue of the International Journal of Radiation Oncology, Biology and Physics, the official journal of ASTRO, the American Society for therapeutic Radiology and Oncology.

"This evaluation of outcome data at the Kuakini Medical Center was performed as a quality assurance measure of proper cancer care," the authors wrote.

"However, the extraordinary results of this patient population are unique. The findings are consistent with other studies reporting unusually low rates of breast cancer recurrence in patients of Japanese ancestry. The biologic factors associated with this population of patients should be explored in future studies."

Kanemori said he's amazed at how much international interest the study has generated. It was featured in the Lancet, one of Britain's top medical journals, and "has been picked up all over the world in major medical health news," he said.