South-Asian women more likely to be diagnosed with later stage breast cancer: Study

A new study confirms a strong link between ethnicity and breast cancer stage at diagnosis for Canadian women

South Asian women are more likely to be diagnosed with later stage breast cancer compared to the general population, while Chinese women are more likely to be diagnosed with early stage cancer, according to a new study by Women's College Hospital and the Institute for Clinical Evaluative Sciences (ICES).

The findings, published in the journal Current Oncology, confirm a strong link between ethnicity and breast cancer stage at diagnosis for Canadian women. An editorial by Dr. Aisha Lofters accompanies the paper and indicates that the study's findings illustrate a health inequality for South Asian women in Ontario that is potentially unnecessary and avoidable.

"Research has long suggested minority groups are among the least likely to be screened for breast cancer, impacting their survival rates and outcomes," said Dr. Ophira Ginsburg, a scientist at Women's College Research Institute. "For many reasons, including ethno-cultural factors, women in these groups are not receiving the screening they need when they need it most. Our findings suggest we have to find better ways to educate and screen these groups so that they can live longer, healthier lives."

In the study, Dr. Ginsburg and colleagues at ICES compared breast cancer stage at diagnosis between Chinese women and the general population (women with breast cancer in Ontario who were not identified as either Chinese or South Asian) and between South Asian women and the general population.

From an analysis of more than 41,000 patients diagnosed with breast cancer between 2005 and 2010, the researchers found:

• South Asian women were more likely to be diagnosed with breast cancer at stages II to IV compared to the general population.
• Chinese women were more likely to be diagnosed at stage I versus stage II and were less likely to be diagnosed with a higher stage of cancer than the general population.
• Fewer South Asian women had a history of breast cancer screening in the past three years, prior to diagnosis.

"Chinese-Canadian communities have been among the first ethno-cultural groups to be offered tailored health promotion information on breast cancer, which may explain the difference between the two groups in our study. Cultural factors, cancer fears and stigma may pose barriers for these women when seeking care for breast problems. Underserved ethno-cultural minority populations, particularly South Asian women living in Ontario, could benefit from carefully developed health promotion and access programs," Dr. Ginsburg said.

The researchers add a more detailed analysis of factors influencing screening uptake is necessary to help tailor health promotion programs to benefit minority populations.