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P Strax

Publications and source records attributed to P Strax.

At least 19 recordsLinked to original sources
PubMed1995

A prospective study of endogenous estrogens and breast cancer in postmenopausal women.

BACKGROUND: Circumstantial evidence links endogenous estrogens to increased risk of breast cancer in women, but direct epidemiologic support is limited. In particular, only a few small prospective studies have addressed this issue. PURPOSE: Our purpose was to assess breast cancer risk in relation to circulating levels of the two major endogenous estrogens, estrone and estradiol, measured before the clinical onset of the disease. METHODS: The association between serum levels of estrogens and the risk of breast cancer was examined in a prospective cohort study of 14,291 New York City women, 35-65 years of age, who received screening for breast cancer at the time of blood sampling and who had not been diagnosed with breast cancer. During the first 5 1/2 years of study, we identified 130 breast cancers among the postmenopausal group (7063 women, 35,509 person-years). The case subjects and twice as many postmenopausal control subjects were included in a case-control study nested within the cohort. Biochemical analyses for percent free estradiol, percent estradiol bound to sex hormone-binding globulin (SHBG), total estradiol, estrone, and follicle-stimulating hormone were performed on sera that had been kept at -80 degrees C since sampling. RESULTS: For increasing quartiles of total estradiol, the odds ratio (ORs) of breast cancer, as adjusted for Quetelet index (weight in kilograms divided by the square of the height in meters), were 1.0, 0.9, 1.8, and 1.8 (P value for trend = .06); the ORs for increasing quartiles of estrone were 1.0, 2.2, 3.7, and 2.5 (P value for trend = .06). For increasing quartiles of free estradiol, defined as the fraction of estradiol that is not bound to proteins, the Quetelet index-adjusted ORs of breast cancer were 1.0, 1.4, 3.0, and 2.9 (P value for trend < .01). When we considered the percent of estradiol bound to SHBG, the Quetelet index-adjusted ORs were 1.0, 0.70, 0.40, and 0.32 (P value for trend < .01), thus suggesting a strong protective effect. These associations persisted or became even stronger when analyses were restricted to women whose samples had been drawn 2 or more years before breast cancer diagnosis. CONCLUSIONS: These data represent the first confirmation in a large prospective epidemiologic study of a link between circulating estrogens and breast cancer risk. Although estrogen levels appeared to fall within the conventional limits of normality in all women under study, those who subsequently developed breast cancer tended to show higher levels of estrone, total estradiol, and free estradiol, and a lower percent of estradiol bound to SHBG than women who remained free of cancer. IMPLICATIONS: Factors that increase endogenous estrogen production or reduce the binding of estradiol to SHBG may increase a woman's risk of developing breast cancer later in life.

Breast Neoplasms↗
PubMed1995

Endogenous estrogens and risk of breast cancer by estrogen receptor status: a prospective study in postmenopausal women.

A positive association between postmenopausal serum levels of total estradiol, percentage of free estradiol, and percentage of estradiol not bound to sex hormone-binding globulin (SHBG) and breast cancer risk was recently reported by the New York University Women's Health Study (P. Toniolo et al., J. Natl. Cancer Inst., 87: 190-197, 1995). Data from this prospective study are used to assess whether the observed associations differ according to estrogen receptor (ER) status of the tumor. Between 1985 and 1991, 7063 postmenopausal women donated blood and completed questionnaires at a large breast cancer screening clinic in New York City. Before 1991, 130 cases of first primary breast cancer were identified by active follow-up of the cohort. For each case, two controls were selected, matching the case on age at first blood donation and length of storage of specimens. Biochemical analyses were performed on sera that had been stored at -80 degrees since sampling. ER information was abstracted from pathology reports. Separate statistical analyses were conducted of ER-positive, ER-negative, and ER-unknown groups (53, 23, and 54 matched sets, respectively). In each of the 3 groups, the mean estradiol and the mean percentage of free estradiol were greater (21-28% and 6-7%, respectively) in cases than in controls. Conversely, the mean percentage of estradiol bound to SHBG was 9-12% lower in cases than in controls. The logistic regression coefficients measuring the strength of the association between estradiol and its free and SHBG-bound fractions and breast cancer risk were similar in the ER-positive, ER-negative, and ER-unknown groups. These data suggest that in postmenopausal women, the association of endogenous estrogens with breast cancer risk is independent of the ER status of the tumor. This result is more compatible with the hypothesis of a progression from ER-positive to ER negative tumors than with the hypothesis that ER status identifies two distinct types of breast cancer.

Aged↗
PubMed1991

Imaging. Follow-up of breast cancer reconstruction cases.

Imaging a breast that has had cancer and been reconstructed has inherent problems, mostly because the reconstruction and the implant may be obscuring recurrence. It should, therefore, be emphasized that such patients require frequent follow-up. Perhaps every 6 months they also need skillful palpation as well as mammography with proper techniques that image as much of breast tissue as possible with the implant displaced as much as possible.

Aftercare↗
PubMed1991

Hair dye use and breast cancer: a case-control study among screening participants.

To investigate whether hair dye use increases the risk of breast cancer, a case-control study was conducted among patients attending a screening center in New York City. The study group consisted of 398 breast cancer cases identified at the screening center between 1977 and 1981, and 790 randomly selected controls screened during the same period. Subjects were interviewed by telephone to obtain information on known risk factors for breast cancer, along with a complete history of hair dye use detailing type of dye, color, duration, frequency, and temporal periods of use. Most subjects (77%) had used hair dye at least once, 38% of the subjects at least 100 times. However, little increased risk of breast cancer was found among hair dye users. The adjusted odds ratio for ever having used hair dye was 0.8 (95% confidence interval 0.6-1.1), and there was no evidence of a trend in risk with increasing number of hair dye uses. The results were the same whether all past exposures were considered or only exposures more than 10 years before disease. Breast cancer risk did not increase with increasing intensity of exposure, as measured by frequency of use or darkness of color. No effect was seen for different types or colors of dye, or for use during different periods of reproductive life. Although personal hair dye use was unrelated to breast cancer risk, there was an adjusted odds ratio of 3.0 (95% confidence interval 1.1-7.8) for 5 or more years of work as a beautician. Overall, the results of this study, taken in conjunction with the findings of other epidemiologic studies, do not implicate hair dye use as an important cause of human breast cancer.

Adult↗
PubMed1991

Endogenous hormones and breast cancer: a prospective cohort study.

A cohort study is under way in New York City to evaluate how levels of endogenous reproductive hormones influence the risk of breast cancer. The study, in which approximately 15,000 women are being recruited, utilizes a prospective design in which volunteers are asked to provide repeated specimens of serum during the period 1985-1992. A case-control study nested within the cohort is planned by which specimens from all cases arising in the population and from a randomly selected sample of time-matched controls will be analyzed and compared. As of December 31, 1989, 13,609 volunteers had donated blood specimens, about 50% of whom had already donated more than once. Of the 187 incident breast cancer cases who are expected to arise in the cohort before the end of 1992, 77 have been detected thus far.

Adult↗
PubMed1990

Detection of breast cancer.

We do not know the cause of breast cancer, nor do we have any way of preventing the disease. All we have is conclusive evidence, based on an 18-year follow-up of the HIP data, that detection of the disease at an earlier than usual stage leads to substantial saving of lives. Our only means for accomplishing this end is through complete breast examination when a woman is apparently well. The examination must include modern mammography with the latest techniques as well as a thorough, competent clinical examination. We must perform periodic mass screening of all women who may be subject to breast cancer--all women older than age 35. Such mass screening procedures will reduce the death rate from the disease by up to 30%. Mass screening is the only means we have to save the lives of many women with breast cancer.

Adult↗
PubMed1988

Mass screening to reduce mortality from breast cancer.

It is generally agreed that the best and possibly the only means to reduce mortality in breast cancer is to detect the disease in its early, most curable stage. This usually means detection when nodes are negative and often when the lesion is nonpalpable. The best method with which to achieve this goal is periodic examination including clinical study and mammography when the woman is apparently well, as is done in mass screening. This applies today to all women over 40 yr old. A baseline examination at age 35 yr is helpful. Radiation risk is today considered to be minimal, if any, and probably is not even measurable. Cost is important. The dedication of the screening institution is most important in this regard. The chief stumbling block is a lack of motivation on the part of subjects to accept or even demand the examination. This needs to be stimulated through contacts with women directly and with their physicians.

Adult↗
PubMed1987

Principles in mass screening for breast cancer.

The only proven means to reduce mortality from breast cancer is detection of the disease when it is still localized to the breast. Such a cancer is usually without signs or symptoms and often not even palpable and can be detected only through mass screening. The H.I.P. study has demonstrated a 30% reduction in mortality in a randomized study group compared to a matched control. The reduction has persisted over 14 years of follow up. Questions of potential hazard from x-ray radiation, questionable significant benefit in women under 50 years, cost and motivation are discussed.

Breast Neoplasms↗
PubMed1985

Selection, follow-up, and analysis in the Health Insurance Plan Study: a randomized trial with breast cancer screening.

Critical decisions made 20 years ago by those who planned the randomized trial at the Health Insurance Plan (HIP) of Greater New York to determine the efficacy of periodic screening for breast cancer are detailed. These decisions affected the age group to be screened, screening modalities, frequency of screening, sample size, primary measures for testing efficacy, and period of follow-up (long term). Results of follow-up, 16 years after entry, indicate that mortality due to breast cancer continues to be lower among study women than controls. Numerically, the differential has been stable; relatively, it has decreased. It is estimated that the study group would have experienced about a 30% reduction in breast cancer mortality if screening had been maintained. Relative case survival rates over a 14-year period after diagnosis show changes in contours of trend lines that result from screening. The study group's trend is slightly concave in contrast to the usual convex curve for the controls. The contour of the curve is more decidedly concave among subjects detected through mammography alone than for other subgroups detected through screening, although the relative survival rate remains highest in the mammography only group. Uncertainty persists about effects of screening in the HIP study on breast cancer mortality among women aged 40-49 years at entry.

Adult↗
PubMed1984

Mass screening for control of breast cancer.

The serious import of breast cancer lies in its potential for metastatic spread, which probably starts early in the course of the disease. Detection of the lesion when immunocompetence can control the metastases leads to long-term survival. This usually involves detection of unsuspected, preclinical disease. This is the important lesson learned from the large screening program of the Health Insurance Plan of New York, where they used palpation and mammography. The substantial reduction in mortality over a matched control group has continued in a 15-year follow-up. Improved mammography techniques at the Guttman Institute, a mass screening project in New York, New York, conducted in cooperation with the American Cancer Society and in the Breast Cancer Detection Demonstration Project, which used the Guttman Institute program as a prototype, have led to substantially improved yield from mammography in screening. Three important factors in mass screening are discussed: (1) benefits versus hazards in mammography, (2) correct age to start screening, and (3) costs of screening.

Adult↗
PubMed1984

Imaging of the breast. A perspective.

It is generally agreed that inspection and palpation of the breast are often inadequate for detection and diagnosis of breast abnormalities. Imaging of the breast, using physical modalities in addition to clinical examination, is important for several reasons, which are discussed in this article.

Adult↗
PubMed1984

Epidemiology of minimal breast cancer among women screened in New York City.

A case-control study based on a screened population in New York City examined epidemiologic risk factor differences between minimal breast cancer (in situ and small invasive carcinomas) and all other breast carcinomas, referred to as clinical breast cancer. Histopathologic re-review of the original slides identified 113 minimal and 792 clinical breast cancers among 1,290 eligible cases; 2,173 randomly selected screenees served as controls. Among those who developed cancer, black women were twice as likely to develop minimal, as compared to clinical, breast cancer. Women who were less than 20 years of age at first live birth had more than double the probability of being diagnosed with minimal breast cancer, whereas women with first live birth at age 30 years or greater and nulliparous women were at 1.5 times the risk of clinical breast cancer. The relative proportion of minimal breast cancer increased with increasing number of children breast fed, being twofold among women who nursed 2 children or more. Unlike clinical breast cancer, minimal breast cancer was not associated with either family history of breast cancer or obesity. Meaningful histologic differences were not apparent between the case subgroups. Except possibly for obesity, these results could not be explained by any plausible diagnostic bias.

Adult↗