Women with breast cancer who consume soy food have lower risk of cancer recurrence - includes challenge

[Guest guest]

Public release date: 8-Dec-2009

http://www.eurekalert.org/pub_releases/2009-12/jaaj-wwb120309.php

Contact: Craig Boerner

craig.boerner@...

JAMA and Archives Journals

Women with breast cancer who consume soy food have lower risk of cancer

recurrence

This release is available in Chinese.

Although there is a concern regarding the safety of soy food consumption

among breast cancer survivors, researchers have found that women in

China who had breast cancer and a higher intake of soy food had an

associated lower risk of death and breast cancer recurrence, according

to a study in the December 9 issue of JAMA.

" Soy foods are rich in isoflavones, a major group of phytoestrogens that

have been hypothesized to reduce the risk of breast cancer. However, the

estrogen-like effect of isoflavones and the potential interaction

between isoflavones and tamoxifen have led to concern about soy food

consumption among breast cancer patients, " the authors write.

Xiao Ou Shu, M.D., Ph.D., of Vanderbilt University Medical Center,

Nashville, Tenn., and colleagues examined the association between soy

isoflavone intake with breast cancer recurrence and survival. The

researchers analyzed data from the Shanghai Breast Cancer Survival

Study, a large, population-based study of 5,042 female breast cancer

survivors in China. Women ages 20 to 75 years with diagnoses of breast

cancer between March 2002 and April 2006 were recruited and followed up

through June 2009. Information on cancer diagnosis and treatment,

lifestyle exposures after cancer diagnosis, and disease progression was

collected at approximately 6 months after cancer diagnosis and was

reassessed at three follow-up interviews conducted at 18, 36, and 60

months after diagnosis. A Shanghai Vital Statistics Registry database

was used to obtain survival information for participants who were lost

to follow-up.

After a median (midpoint) follow-up of 3.9 years, 444 total deaths and

534 recurrences or breast cancer-related deaths were documented among

the group of 5,033 surgically-treated breast cancer patients. Soy food

intake, as measured by either soy protein or soy isoflavone intake, was

inversely associated with mortality and recurrence. Patients in the

group with the highest intake of soy protein had a 29 percent lower risk

of death during the study period, and a 32 percent lower risk of breast

cancer recurrence compared to patients with the lowest intake of soy

protein. The adjusted 4-year mortality rates were 10.3 percent and 7.4

percent and the 4-year recurrence rates were 11.2 percent and 8.0

percent, respectively, for women with the lowest and highest groups of

soy protein intake.

" The inverse association was evident among women with either estrogen

receptor–positive or –negative breast cancer and was present in both

users and nonusers of tamoxifen, " the researchers write.

" In summary, in this population-based prospective study, we found that

soy food intake is safe and was associated with lower mortality and

recurrence among breast cancer patients. The association of soy food

intake with mortality and recurrence appears to follow a linear

dose-response pattern until soy food intake reached 11 grams/day of soy

protein; no additional benefits on mortality and recurrence were

observed with higher intakes of soy food. This study suggests that

moderate soy food intake is safe and potentially beneficial for women

with breast cancer. "

(JAMA. 2009;302[22]:2437-2443. Available pre-embargo to the media at

www.jamamedia.org)

Editor's Note: Please see the article for additional information,

including other authors, author contributions and affiliations,

financial disclosures, funding and support, etc.

Editorial: Challenges in Design and Interpretation of Observational

Research on Health Behaviors and Cancer Survival

Ballard-Barbash, M.D., M.P.H., of the National Cancer Institute,

Bethesda, Md., and n L. Neuhouser, Ph.D., of the Fred Hutchinson

Cancer Research Center, Seattle, write in an accompanying editorial that

while this study provides important information, there are several

concerns, including differences in the quality, type and quantity of soy

food intake between China and the U.S. (47 mg/d vs. 1 to 6 mg/d,

respectively, average isoflavone intake). Also, they point out the

relatively short median follow-up time of the study (4 years); that

there likely are differences in screening rates in China compared with

the U.S.; and a number of factors may make it difficult to compare

stage- and treatment-specific results in China with outcomes in the U.S.

" Even though the findings by Shu et al suggest that consumption of soy

foods among breast cancer patients is probably safe, studies in larger

cohorts are required to understand the effects of these foods among

diverse clinical subgroups of breast cancer patients and survivors. In

the meantime, clinicians can advise their patients with breast cancer

that soy foods are safe to eat and that these foods may offer some

protective benefit for long-term health. Moreover, the potential

benefits are confined to soy foods, and inferences should not be made

about the risks or benefits of soy-containing dietary supplements.

Patients with breast cancer can be assured that enjoying a soy latte or

indulging in pad thai with tofu causes no harm and, when consumed in

plentiful amounts, may reduce risk of disease recurrence. "

(JAMA. 2009;302[22]:2483-2484. Available pre-embargo to the media at

www.jamamedia.org)

Editor's Note: Please see the article for additional information,

including financial disclosures, funding and support, etc.

[Guest guest]

I think it should be noted that the research was done in CHINA; chineese have

been eating soy for a very long time as opposed to us Westerners.

Subject: Women with breast cancer who consume soy food have lower risk

of cancer recurrence - includes challenge

To: Nutrition_Reports

Date: Wednesday, December 9, 2009, 7:23 AM

Public release date: 8-Dec-2009

http://www.eurekalert.org/pub_releases/2009-12/jaaj-wwb120309.php

Contact: Craig Boerner

craig.boerner@...

JAMA and Archives Journals

Women with breast cancer who consume soy food have lower risk of cancer

recurrence

This release is available in Chinese.

Although there is a concern regarding the safety of soy food consumption

among breast cancer survivors, researchers have found that women in

China who had breast cancer and a higher intake of soy food had an

associated lower risk of death and breast cancer recurrence, according

to a study in the December 9 issue of JAMA.

" Soy foods are rich in isoflavones, a major group of phytoestrogens that

have been hypothesized to reduce the risk of breast cancer. However, the

estrogen-like effect of isoflavones and the potential interaction

between isoflavones and tamoxifen have led to concern about soy food

consumption among breast cancer patients, " the authors write.

Xiao Ou Shu, M.D., Ph.D., of Vanderbilt University Medical Center,

Nashville, Tenn., and colleagues examined the association between soy

isoflavone intake with breast cancer recurrence and survival. The

researchers analyzed data from the Shanghai Breast Cancer Survival

Study, a large, population-based study of 5,042 female breast cancer

survivors in China. Women ages 20 to 75 years with diagnoses of breast

cancer between March 2002 and April 2006 were recruited and followed up

through June 2009. Information on cancer diagnosis and treatment,

lifestyle exposures after cancer diagnosis, and disease progression was

collected at approximately 6 months after cancer diagnosis and was

reassessed at three follow-up interviews conducted at 18, 36, and 60

months after diagnosis. A Shanghai Vital Statistics Registry database

was used to obtain survival information for participants who were lost

to follow-up.

After a median (midpoint) follow-up of 3.9 years, 444 total deaths and

534 recurrences or breast cancer-related deaths were documented among

the group of 5,033 surgically-treated breast cancer patients. Soy food

intake, as measured by either soy protein or soy isoflavone intake, was

inversely associated with mortality and recurrence. Patients in the

group with the highest intake of soy protein had a 29 percent lower risk

of death during the study period, and a 32 percent lower risk of breast

cancer recurrence compared to patients with the lowest intake of soy

protein. The adjusted 4-year mortality rates were 10.3 percent and 7.4

percent and the 4-year recurrence rates were 11.2 percent and 8.0

percent, respectively, for women with the lowest and highest groups of

soy protein intake.

" The inverse association was evident among women with either estrogen

receptor–positive or –negative breast cancer and was present in both

users and nonusers of tamoxifen, " the researchers write.

" In summary, in this population-based prospective study, we found that

soy food intake is safe and was associated with lower mortality and

recurrence among breast cancer patients. The association of soy food

intake with mortality and recurrence appears to follow a linear

dose-response pattern until soy food intake reached 11 grams/day of soy

protein; no additional benefits on mortality and recurrence were

observed with higher intakes of soy food. This study suggests that

moderate soy food intake is safe and potentially beneficial for women

with breast cancer. "

(JAMA. 2009;302[22]:2437-2443. Available pre-embargo to the media at

www.jamamedia.org)

Editor's Note: Please see the article for additional information,

including other authors, author contributions and affiliations,

financial disclosures, funding and support, etc.

Editorial: Challenges in Design and Interpretation of Observational

Research on Health Behaviors and Cancer Survival

Ballard-Barbash, M.D., M.P.H., of the National Cancer Institute,

Bethesda, Md., and n L. Neuhouser, Ph.D., of the Fred Hutchinson

Cancer Research Center, Seattle, write in an accompanying editorial that

while this study provides important information, there are several

concerns, including differences in the quality, type and quantity of soy

food intake between China and the U.S. (47 mg/d vs. 1 to 6 mg/d,

respectively, average isoflavone intake). Also, they point out the

relatively short median follow-up time of the study (4 years); that

there likely are differences in screening rates in China compared with

the U.S.; and a number of factors may make it difficult to compare

stage- and treatment-specific results in China with outcomes in the U.S.

" Even though the findings by Shu et al suggest that consumption of soy

foods among breast cancer patients is probably safe, studies in larger

cohorts are required to understand the effects of these foods among

diverse clinical subgroups of breast cancer patients and survivors. In

the meantime, clinicians can advise their patients with breast cancer

that soy foods are safe to eat and that these foods may offer some

protective benefit for long-term health. Moreover, the potential

benefits are confined to soy foods, and inferences should not be made

about the risks or benefits of soy-containing dietary supplements.

Patients with breast cancer can be assured that enjoying a soy latte or

indulging in pad thai with tofu causes no harm and, when consumed in

plentiful amounts, may reduce risk of disease recurrence. "

(JAMA. 2009;302[22]:2483-2484. Available pre-embargo to the media at

www.jamamedia.org)

Editor's Note: Please see the article for additional information,

including financial disclosures, funding and support, etc.

------------------------------------

[Guest guest]

They also eat soy differently and start at a much younger age. The research I

read from the Shanghai Study was that soy was protective if eaten early in life

but not if eaten later in life. The Shanghai Study also found that exercise was

important. Not such a good idea to report each little variable separately!

Sharon Salomon, MS, RD

1924 East Flynn Lane

Phoenix, AZ 85016

http://diaryofadietingdietitian.blogspot.com

Follow me on twitter at eatingagain

In a message dated 12/09/09 14:29:35 US Mountain Standard Time,

anradmand@... writes:

I think it should be noted that the research was done in CHINA; chineese have

been eating soy for a very long time as opposed to us Westerners.

Subject: Women with breast cancer who consume soy food have lower risk

of cancer recurrence - includes challenge

To: Nutrition_Reports

Date: Wednesday, December 9, 2009, 7:23 AM

Public release date: 8-Dec-2009

http://www.eurekalert.org/pub_releases/2009-12/jaaj-wwb120309.php

Contact: Craig Boerner

craig.boerner@...

JAMA and Archives Journals

Women with breast cancer who consume soy food have lower risk of cancer

recurrence

This release is available in Chinese.

Although there is a concern regarding the safety of soy food consumption

among breast cancer survivors, researchers have found that women in

China who had breast cancer and a higher intake of soy food had an

associated lower risk of death and breast cancer recurrence, according

to a study in the December 9 issue of JAMA.

" Soy foods are rich in isoflavones, a major group of phytoestrogens that

have been hypothesized to reduce the risk of breast cancer. However, the

estrogen-like effect of isoflavones and the potential interaction

between isoflavones and tamoxifen have led to concern about soy food

consumption among breast cancer patients, " the authors write.

Xiao Ou Shu, M.D., Ph.D., of Vanderbilt University Medical Center,

Nashville, Tenn., and colleagues examined the association between soy

isoflavone intake with breast cancer recurrence and survival. The

researchers analyzed data from the Shanghai Breast Cancer Survival

Study, a large, population-based study of 5,042 female breast cancer

survivors in China. Women ages 20 to 75 years with diagnoses of breast

cancer between March 2002 and April 2006 were recruited and followed up

through June 2009. Information on cancer diagnosis and treatment,

lifestyle exposures after cancer diagnosis, and disease progression was

collected at approximately 6 months after cancer diagnosis and was

reassessed at three follow-up interviews conducted at 18, 36, and 60

months after diagnosis. A Shanghai Vital Statistics Registry database

was used to obtain survival information for participants who were lost

to follow-up.

After a median (midpoint) follow-up of 3.9 years, 444 total deaths and

534 recurrences or breast cancer-related deaths were documented among

the group of 5,033 surgically-treated breast cancer patients. Soy food

intake, as measured by either soy protein or soy isoflavone intake, was

inversely associated with mortality and recurrence. Patients in the

group with the highest intake of soy protein had a 29 percent lower risk

of death during the study period, and a 32 percent lower risk of breast

cancer recurrence compared to patients with the lowest intake of soy

protein. The adjusted 4-year mortality rates were 10.3 percent and 7.4

percent and the 4-year recurrence rates were 11.2 percent and 8.0

percent, respectively, for women with the lowest and highest groups of

soy protein intake.

" The inverse association was evident among women with either estrogen

receptor–positive or –negative breast cancer and was present in both

users and nonusers of tamoxifen, " the researchers write.

" In summary, in this population-based prospective study, we found that

soy food intake is safe and was associated with lower mortality and

recurrence among breast cancer patients. The association of soy food

intake with mortality and recurrence appears to follow a linear

dose-response pattern until soy food intake reached 11 grams/day of soy

protein; no additional benefits on mortality and recurrence were

observed with higher intakes of soy food. This study suggests that

moderate soy food intake is safe and potentially beneficial for women

with breast cancer. "

(JAMA. 2009;302[22]:2437-2443. Available pre-embargo to the media at

www.jamamedia.org)

Editor's Note: Please see the article for additional information,

including other authors, author contributions and affiliations,

financial disclosures, funding and support, etc.

Editorial: Challenges in Design and Interpretation of Observational

Research on Health Behaviors and Cancer Survival

Ballard-Barbash, M.D., M.P.H., of the National Cancer Institute,

Bethesda, Md., and n L. Neuhouser, Ph.D., of the Fred Hutchinson

Cancer Research Center, Seattle, write in an accompanying editorial that

while this study provides important information, there are several

concerns, including differences in the quality, type and quantity of soy

food intake between China and the U.S. (47 mg/d vs. 1 to 6 mg/d,

respectively, average isoflavone intake). Also, they point out the

relatively short median follow-up time of the study (4 years); that

there likely are differences in screening rates in China compared with

the U.S.; and a number of factors may make it difficult to compare

stage- and treatment-specific results in China with outcomes in the U.S.

" Even though the findings by Shu et al suggest that consumption of soy

foods among breast cancer patients is probably safe, studies in larger

cohorts are required to understand the effects of these foods among

diverse clinical subgroups of breast cancer patients and survivors. In

the meantime, clinicians can advise their patients with breast cancer

that soy foods are safe to eat and that these foods may offer some

protective benefit for long-term health. Moreover, the potential

benefits are confined to soy foods, and inferences should not be made

about the risks or benefits of soy-containing dietary supplements.

Patients with breast cancer can be assured that enjoying a soy latte or

indulging in pad thai with tofu causes no harm and, when consumed in

plentiful amounts, may reduce risk of disease recurrence. "

(JAMA. 2009;302[22]:2483-2484. Available pre-embargo to the media at

www.jamamedia.org)

Editor's Note: Please see the article for additional information,

including financial disclosures, funding and support, etc.

------------------------------------