(HealthDay News) – For Chinese women, consumption of cruciferous vegetables after breast cancer diagnosis is associated with improved survival in a dose-response pattern.
To evaluate the impact of cruciferous vegetable consumption on outcomes after breast cancer diagnosis, Sarah J. Nechuta, MPH, PhD, from Vanderbilt University in Nashville, TN, and colleagues recruited 4,886 Chinese women aged 20–75 years with incident stage I–IV breast cancer, within six months of diagnosis, during 2002–2006. Data were collected on clinical characteristics, sociodemographics, and lifestyle factors. At 18 months and at 36 months, intake of cruciferous vegetables was reassessed.
After a median follow-up of 5.2 years, the researchers identified 587 deaths (496 breast cancer-related) and 615 cases of recurrence. At six and 36 months after diagnosis there was an increase in cruciferous vegetable intake. Intake correlated with improved survival in a dose-response pattern, following adjustment for sociodemographic, clinical, and lifestyle factors. Compared with the lowest quartile of intake, across increasing quartiles, the multivariable hazard ratios were 0.73, 0.51, and 0.38 for total mortality; 0.78, 0.53, and 0.38 for breast cancer-specific mortality; and 0.79, 0.71, and 0.65 for recurrence. After exclusion of the first year of observation, the associations persisted, although the correlation for recurrence was no longer significant.
“Commonly consumed cruciferous vegetables in China include turnips, Chinese cabbage/bok choy, and greens, while broccoli and brussels sprouts are the more commonly consumed cruciferous vegetables in the United States and other Western countries,” Nechuta said in a statement. “Second, the amount of intake among Chinese women is much higher than that of US women. The level of bioactive compounds such as isothiocyanates and indoles, proposed to play a role in the anticancer effects of cruciferous vegetables, depend on both the amount and type of cruciferous vegetables consumed.”