Risk Factors for Benign Breast Disease and their Relation with Breast Cancer Risk. Pooled Information from Epidemiologic Studies

Family History, Reproductive, and Lifestyle Risk Factors for Fibroadenoma and Breast Cancer

Background

To understand which breast cancer (BC) risk factors also increase the risk of fibroadenoma and investigate whether these factors have the same effect in BC patients with previous fibroadenoma.

Methods

Using multistate survival analysis on a large dataset (n = 58 322), we examined the effects of BC risk factors on transitions between three states: event-free, biopsy-confirmed fibroadenoma, and BC. Hazard ratios and corresponding 95% confidence intervals associated with covariate effects were estimated. Median follow-up time was 25.3 years.

Results

The mean ages at diagnosis of fibroadenoma and BC were 42.6 and 48.3 years, respectively. Participant characteristics known to increase the risk of BC were found to increase the risk of fibroadenoma (family history of BC and higher education). Participant characteristics known to confer protective effects for BC (older age at menarche, more children, and larger childhood body size) were found to reduce fibroadenoma risk. The effect sizes associated with the direct transitions from event-free to fibroadenoma and BC were generally not different for the covariates tested. Age at fibroadenoma diagnosis was associated with the transition from fibroadenoma to BC (hazard ratio_{per year increase} = 1.07 [95% confidence interval = 1.03 to 1.12]).

Conclusion

We showed that biopsy-confirmed fibroadenomas shared many risk factors with BC. More work is needed to understand the relationships between fibroadenoma and BC to identify women who are at high risk of developing BC after a fibroadenoma diagnosis.

Benign Breast Diseases: Evaluation and Management

Benign breast disease is a spectrum of common disorders. The majority of patients with a clinical breast lesion will have benign process. Management involves symptom control when present, pathologic-based and imaging-based evaluation to distinguish from a malignant process, and counseling for patients that have an increased breast cancer risk due to the benign disorder.

In vivo non-invasive optical imaging of temperature-sensitive co-polymeric nanohydrogel

Assessment of hyperthermia in pathological tissue is a promising strategy for earlier diagnosis of malignant tumors. In this study, temperature-sensitive co-polymeric nanohydrogel poly(N-isopropylacrylamide-co-acrylic acid) (PNIPA-co-AA) was successfully synthesized by the precipitation polymerization method. The diameters of nanohydrogels were controlled to be less than 100 nm. Also the lower critical solution temperature (LCST, 40 °C) was manipulated above physiological temperature after integration of near-infrared (NIR) organic dye (heptamethine cyanine dye, HMCD) within its interior cores. NIR laser light (765 nm), together with sensitive charge coupled device (CCD) cameras, were designed to construct an NIR imaging system. The dynamic behaviors of PNIPA-co-AA-HMCD composites in denuded mice with or without local hyperthermia treatment were real-time monitored by an NIR imager. The results showed that the PNIPA-co-AA-HMCD composites accumulated in the leg treated with local heating and diffused much slower than that in the other leg without heating. The results demonstrated that the temperature-responsive PNIPA-co-AA-HMCD composites combining with an NIR imaging system could be an effective temperature mapping technique, which provides a promising prospect for earlier tumor diagnosis and thermally related therapeutic assessment.

Benign breast diseases: classification, diagnosis, and management

Benign breast diseases constitute a heterogeneous group of lesions including developmental abnormalities, inflammatory lesions, epithelial and stromal proliferations, and neoplasms. In this review, common benign lesions are summarized and their relationship to the development of subsequent breast cancer is emphasized.

The potential role of dynamic thermal analysis in breast cancer detection

BACKGROUND

It is presently well accepted that the breast exhibits a circadian rhythm reflective of its physiology. There is increasing evidence that rhythms associated with malignant cells proliferation are largely non-circadian. Cancer development appears to generate its own thermal signatures and the complexity of these signatures may be a reflection of its degree of development. The limitations of mammography as a screening modality especially in young women with dense breasts necessitated the development of novel and more effective screening strategies with a high sensitivity and specificity. The aim of this prospective study was to evaluate the feasibility of dynamic thermal analysis (DTA) as a potential breast cancer screening tool.

METHODS

173 women undergoing mammography as part of clinical assessment of their breast symptoms were recruited prior to having a biopsy. Thermal data from the breast surface were collected every five minutes for a period of 48 hours using eight thermal sensors placed on each breast surface [First Warning System (FWS), Lifeline Biotechnologies, Florida, USA]. Thermal data were recorded by microprocessors during the test period and analysed using specially developed statistical software. Temperature points from each contra-lateral sensor are plotted against each other to form a thermal motion picture of a lesion's physiological activity. DTA interpretations [positive (abnormal thermal signature) and negative (normal thermal signature)] were compared with mammography and final histology findings.

RESULTS

118 (68%) of participating patients, were found to have breast cancer on final histology. Mammography was diagnostic of malignancy (M5) in 55 (47%), indeterminate (M3, M4) in 54 (46%) and normal/benign (M1, M2) in 9 (8%) patients. DTA data was available on 160 (92.5%) participants. Using our initial algorithm, DTA was interpreted as positive in 113 patients and negative in 47 patients. Abnormal thermal signatures were found in 76 (72%) out of 105 breast cancer patients and 37 of the 55 benign cases. Then we developed a new algorithm using multiple-layer perception and SoftMax output artificial neural networks (ANN) on a subgroup (n = 38) of recorded files. The sensitivity improved to 76% (16/21) and false positives decreased to 26% (7/27)

CONCLUSION

DTA of the breast is a feasible, non invasive approach that seems to be sensitive for the detection of breast cancer. However, the test has a limited specificity that can be improved further using ANN. Prospective multi-centre trials are required to validate this promising modality as an adjunct to screening mammography especially in young women with dense breasts.

The evolving role of the dynamic thermal analysis in the early detection of breast cancer

It is now recognised that the breast exhibits a circadian rhythm which reflects its physiology. There is increasing evidence that rhythms associated with malignant cells proliferation are largely non-circadian and that a circadian to ultradian shift may be a general correlation to neoplasia.Cancer development appears to generate its own thermal signatures and the complexity of these signatures may be a reflection of its degree of development.The limitations of mammography as a screening modality especially in young women with dense breasts necessitated the development of novel and more effective screening strategies with a high sensitivity and specificity. Dynamic thermal analysis of the breast is a safe, non invasive approach that seems to be sensitive for the early detection of breast cancer.This article focuses on dynamic thermal analysis as an evolving method in breast cancer detection in pre-menopausal women with dense breast tissue. Prospective multi-centre trials are required to validate this promising modality in screening.The issue of false positives require further investigation using molecular genetic markers of malignancy and novel techniques such as mammary ductoscopy.

Comparison of age at first full-term pregnancy between women with breast cancer and women with benign breast diseases

Benign breast diseases have a broadly similar risk profile to that of breast cancer, possibly reflecting a similar underlying endocrine milieu. We have hypothesized that a crucial distinction between breast cancer and benign breast diseases is that mammary gland terminal differentiation has not been successfully accomplished among women who tend to develop breast cancer. From October 2001 to December 2002, information concerning breast cancer risk factors and sociodemographic characteristics was collected from 174 women with breast cancer and 116 women with benign breast diseases, all 30 years old or older, who were histologically diagnosed at a major prevention center in Athens, Greece. Among the examined breast cancer risk factors, only age at first full-term pregnancy was significantly associated with the odds of having breast cancer rather than benign breast disease, and the association was evident among premenopausal [odds ratio (OR) per 5 years = 1.76, 95% confidence interval (CI) 1.10-2.93] and postmenopausal (OR = 2.10, 95% CI 1.16-3.71) women, as well as among all women (OR = 1.93, 95% CI 1.34-2.70). There was no evidence that any of the remaining breast cancer risk factors could discriminate between breast cancer and benign breast diseases. We conclude that early age at first pregnancy may convey substantial protection against breast cancer risk among women with benign breast diseases, probably operating through induction of terminal differentiation of mammary gland cells. The finding is accentuated by the fact that women with benign breast diseases are already at a relatively high risk for breast cancer.

Trends in benign breast tumors in Japanese women, 1973-1995: experience of Hiroshima Tumor Tissue Registry

Although some benign breast lesions such as multiple intraductal papilloma have been pointed out as a risk factor for breast cancer, there is little documentation about trends in the incidence of benign tumors of the breast in Japanese women. The author conducted an epidemiological study using data abstracted from the Hiroshima Tumor Tissue Registry file, which includes cases of malignant and benign neoplasms in Hiroshima prefecture between 1973 and 1995. A total of 17064 cases of female breast tumor were registered in the file between 1973 and 1995. The registration rate for fibroadenoma of the female breast was 19.5 among females and peaked during the 5-year period 1983 - 1987, while the fibroadenoma registration rate in Hiroshima gradually decreased between 1988 and 1995. The registration rate for intraductal papilloma has risen substantially in Hiroshima, with about a 5-fold increase among females between 1973 and 1995. The mean proportion of fibroadenoma cases accompanied by malignant tumors of the breast was 1.85%, and there was no significant change in the mean proportion between 1973 and 1995 (P = 0.17). On the other hand, the mean proportion of intraductal papilloma cases accompanied by malignant tumors of the breast gradually rose with about a 14-fold increase among females between 1973 and 1995. The significance of intraductal papilloma as a risk factor for breast cancer may have increased.

Risk factors for histologically confirmed benign breast tumors

A case-control study of 156 cases of various types of benign breast disease (BBD) and 156 population controls was conducted to investigate the role of various behavioral, reproductive, and hormonal factors in the etiology of these breast disorders. Our results indicate that the distinct histological groups of BBD differ from each other in respect to possible risk factors. Small sample size poses severe restrictions on the conclusiveness of the results and thus they should be considered as preliminary and suggestive. Our results do not support the notion that BBD could be considered as a uniform entity with common risk factors.