HONG KONG -?A study by the Hong Kong Breast Cancer Foundation has found that chemotherapy before surgery can help some breast cancer patients with more aggressive types of tumors and may lead to a higher survival rate, the foundation told Xinhua on Thursday.

The Hong Kong Breast Cancer Registry (HKBCR) of the foundation did the survey by comparing data of over 12,700 Hong Kong women diagnosed with invasive breast cancers during two five-year periods, respectively from 2006 and from 2011.

Carol Kwok, who led the study, said that pre-surgery chemotherapy may bring "new hopes" for breast cancer patients as a higher pathological complete response (PCR) rate was observed in some aggressive tumor types such as the HER2-positive and the triple-negative breast cancers.

"Pathological complete response rate means complete disappearance of invasive cancers in the breast and the axillary lymph nodes," she said, "And the study has demonstrated that, with increase in the PCR rate, those patients with PCR rate showed a higher chance of disease-free survival."