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Breast Cancer Risk Factors
IN THIS ISSUE
ERT Affects Mammography
Previous studies have shown that
mammographic breast density increases
with estrogen replacement therapy
(ERT). The present study indicates that
current use of ERT is associated with
lower specificity (more false-positive
readings) and lower sensitivity (more
false-negative readings) of screening
mammography. These factors could increase the biopsy rate and cost and decrease the effectiveness of breast cancer
screening, the researchers say.
Laya et al. (p. 643) studied 8779 postmenopausal women aged 50 years or
older who underwent screening mammography and filled out questionnaires
about ERT use and personal health histories. One year later, cancers had been diagnosed in 63 women, of whom 56 had
true-positive readings and seven had falsenegative readings on their screening
mammograms.
Results showed that mammographic
specificities for never users, former users,
and current users of ERT were 86%, 86%,
and 82%, respectively; mammographic
sensitivities were 94%, 94%, and 69%,
respectively.
In an editorial, Black and Fletcher
(p. 627) say the findings by Laya et al.
provide direct evidence that ERT lowers
mammographic specificity and sensitivity. Lower specificity, they suggest, could
substantially increase false-positive rates
and the resulting costs; lower sensitivity
may also substantially decrease the ability of screening to reduce breast cancer
mortality. Nevertheless, the benefits of
ERT in reducing mortality from heart disease and osteoporosis may still outweigh
these drawbacks, the editorial writers say.
They also suggest that the findings of
Laya et al. be replicated because 1) the
statistically significant differences in
specificity were small and 2) although the
differences in sensitivity were larger, the
confidence intervals were wide.
They conclude that women should be
informed of the multiple effects of ERT
so they can make decisions based on facts
and personal preference.
Height, recent adiposity (weight/
height1-5), and recent weight change (between current and preceding decades of
life) are predictors of breast cancer risk in
Asian-American women, a study suggests. Increased adiposity and weight
gain in the decade preceding diagnosis
may be especially predictive of increased
risk, Ziegler et al. (p. 650) report. While
these findings need confirmation in other
studies, the researchers suggest that
weight maintenance and/or loss might
have a substantial and relatively rapid
impact—possibly within a decade—on
breast cancer risk. Whether specific
changes in diet and physical activity must
accompany the weight loss needs further
investigation, they say.
The researchers used interviews to
collect information about height, usual
adult weight, and usual weight in each
decade of life from 597 Asian-American
women with breast cancer, aged 20-55
years, and from 966 control subjects.
They found that women who were 66
inches or more in height had twice the
breast cancer risk (relative risk = 2.01) of
women 59 inches or less in height. Except
for a reduced risk in the heavy, younger
women, risk was positively associated with
usual adult adiposity. Trends inriskbecame
more striking as adiposity in each succeeding decade of adult life was considered.
Psychological Predictors
Previous studies have found that psychological factors, like depression or hostility, might predict length of survival. The
present study by Tross et al. (p. 661) finds
no evidence that psychological distress —
as measured by the Symptom Check List90-Revised questionnaire (SCL-90-R)
covering depression, hostility, and other
psychological symptom areas—predicted
disease-free or overall survival in women
with stage II breast cancer. The investigators recommend that, rather than focusing
on general psychological symptoms, future research should concentrate on specific theory-driven constructs as potential
predictors of survival.
Using the SCL-90-R, Tross et al. identified low, medium, and high levels of
distress in 280 women with stage II breast
cancer who were taking part in a larger
trial of adjuvant therapy regimens involv-
Journal of the National Cancer Institute, Vol. 88, No. 10, May 15, 1996
ing cyclophosphamide-methotrexatefluorouracil-vincristine-prednisone for
two 6-week cycles or six 4-week cycles
with or without vinblastine-doxorubicinthiotepa-fluoxymesterone.
Stepwise Cox statistical regressions
that controlled for sociodemographic and
medical variables found no significant
predictive effect of level of distress on
disease-free and overall survival.
In an editorial, Spiegel (p. 629) says
the study by Tross et al. is an exceptionally fine investigation of the relationship
between psychological distress and cancer survival. The study, however, may be
limited by sample bias, he says: For example, women may have chosen to participate (self-selected) because they
lacked the depression that might predict
poorer outcome or the feistiness (uncooperativeness) that might predict better
outcome. Spiegel reviews current knowledge about the effects of the mind on
cancer, concluding that research on more
specific constructs, such as suppression
of distress, active coping strategies, and
psychosocial intervention, should provide
a more definitive test of the mind-body
hypothesis.
5-FU and Colorectal Cancer
Hansen et al. (p. 668) found no statistically significant difference in overall
survival in patients with previously untreated metastatic colorectal cancer who
were treated with continuous-infusion
fluorouracil (5-FU) compared with bolus
5-FU. Continuous-infusion 5-FU, however, produced better response rates with
less toxicity and longer time to disease
progression, and the researchers suggest
that it be considered as initial therapy for
advanced colorectal cancer.
Brain Lymphoma and AIDS
The incidence of brain lymphoma appears to be several thousand times higher
in persons with acquired immunodeficiency syndrome (AIDS) than in the general population, Cote et al. (p. 675) report.
The increased brain lymphoma incidence
in the AIDS population helped raise the
overall incidence ninefold between 1980
and 1989, they say. But the researchers
also detected a significant increase in
brain lymphoma among persons without
AIDS that remains unexplained.
IN THIS ISSUE
625
The Surgery Branch
of The National Cancer Institute Is Seeking
Patients with the Following Malignancies for
Combined Modality or Innovative
Immunotherapy Programs:
• METASTATIC MELANOMA AND KIDNEY CANCER •
• STAGE II OR LOCALLY ADVANCED BREAST CANCER •
• METASTATIC COLORECTAL CANCER TO THE LIVER •
• LOCOREGIONAL GASTRIC OR PANCREATIC CANCER •
• MESOTHELIOMA, PULMONARY METASTASES, STAGE III A
AND B LUNG CANCER OR ESOPHAGEAL CANCER •
• LOCALIZED SOFT TISSUE SARCOMAS •
• PERITONEAL CARCINOMATOSIS •
Care for all patients is provided at the clinical center at the
National Institutes of Health in Bethesda, Maryland.
For more information on cancer programs, please call
(301) 496-1533
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