Breast size and breast cancer: a systematic review

Breast volume in non-obese females is related to breast adipose cell hypertrophy, inflammation, and COX2 expression

BACKGROUND

Breast hypertrophy seems to be a risk factor for breast cancer and the amount and characteristics of breast adipose tissue may play important roles. The main aim of this study was to investigate associations between breast volume in normal weight women and hypertrophic adipose tissue and inflammation.

METHODS

Fifteen non-obese women undergoing breast reduction surgery were examined. Breast volume was measured with plastic cups and surgery was indicated if the breast was 800 ml or larger according to Swedish guidelines. We isolated adipose cells from the breasts and ambient subcutaneous tissue to measure cell size, cell inflammation and other known markers of risk of developing breast cancer including COX2 gene activation and MAPK, a cell proliferation regulator.

RESULTS

Breast adipose cell size was characterized by cell hypertrophy and closely related to breast volume. The breast adipose cells were also characterized by being pro-inflammatory with increased IL-6, IL-8, IL-1β, CCL-2, TNF-a and an increased marker of cell senescence GLB1/β-galactosidase, commonly increased in hypertrophic adipose tissue. The prostaglandin synthetic marker COX2 was also increased in the hypertrophic cells and COX2 has previously been shown to be an important marker of risk of developing breast cancer. Interestingly, the phosphorylation of the proliferation marker MAPK was also increased in the hypertrophic adipose cells.

CONCLUSION

Taken together, these findings show that increased breast volume in non-obese women is associated with adipose cell hypertrophy and dysfunction and characterized by increased inflammation and other markers of increased risk for developing breast cancer.

TRIAL REGISTRATION

Projektdatabasen FoU i VGR, project number: 249191 (https://www.researchweb.org/is/vgr/project/249191).

Causes and Risk Factors of Breast Cancer, What Do We Know for Sure? An Evidence Synthesis of Systematic Reviews and Meta-Analyses

Breast cancer affected more than 2.3 million women in 2022 and is the most diagnosed cancer among women worldwide. The incidence rates are greater in developed regions and are significantly higher among women with higher education and socioeconomic status. Therefore, it is reasonable to assume that the way women live their lives may impact their risk of being diagnosed with breast cancer. This systematic review aimed to identify what is known about the causes and risk factors of breast cancer, excluding genetic causes. A comprehensive systematic search identified 2387 systematic reviews, 122 were included and six overall themes identified. In our "top list" with the 36 most important findings, a study of breast density had the highest effect size for increasing the risk of breast cancer, and a high sex-hormone-binding globulin level was the most protective factor. Many of the included studies investigating the same topics had conflicting results. The conclusion from this evidence synthesis reveals a lack of consensus of factors associated with the causes and risk of breast cancer. These findings suggest that recommendations about lifestyle and breast cancer should be made with caution.

Obesity bias: How can this underestimated problem affect medical decisions in healthcare? A systematic review

INTRODUCTION

Obesity is often labeled as a physical characteristic of a patient rather than a disease and it is subject to obesity bias by health providers, which harms the equality of healthcare in this population.

OBJECTIVE

Identifying whether obesity bias interferes in clinical decision-making in the treatment of patients with obesity.

METHODS

A systematic review of observational studies published between 1993 and 2023 in MEDLINE, Embase, and Cochrane Library on obesity bias and therapeutic decisions was carried out. The last search was conducted on June 30, 2023. The main outcome was the difference between clinical decisions in the treatment of individuals with and without obesity. The Newcastle-Ottawa scale for observational studies was used to assess for quality. After the selection process, articles were presented in narrative and thematic synthesis categories to better organize the descriptive analysis.

RESULTS

Of the 2546 records identified, 13 were included. The findings showed fewer screening exams for cancer in patients with obesity, who were also susceptible to less frequent pharmacological treatment intensification in the management of diabetes. Women with obesity received fewer pelvic exams and evidence of diminished visual contact and physician confidence in treatment adherence was reported. Some studies found no disparities in treatment for abdominal pain and tension headaches between patients presented with and without obesity.

CONCLUSION

The presence of obesity bias has negative effects on medical decision-making and on the quality of care provided to patients with obesity. These findings reveal the urgent necessity for reflection and development of strategies to mitigate its adverse impacts. (The protocol was registered with the international prospective register of systematic reviews, PROSPERO, under the number CRD42022307567).

Oncogenic BRCA1,2 Mutations in the Human Lineage-A By-Product of Sexual Selection?

In this review, we discuss the long-known problem of tissue-specific carcinogenesis in BRCA1 and BRCA2 mutation carriers: while the genes are expressed ubiquitously, increased cancer risk is observed mostly in the breast and ovaries, and to a much lesser extent, in some other tissues such as the prostate or pancreas. We reevaluate hypotheses on the evolutionary origin of these mutations in humans. Also, we align together the reports that at least some great apes have much lower risks of epithelial cancers in general and breast cancer in particular with the fact that humans have more voluminous breast tissue as compared to their closest extant relatives, particularly chimpanzees and bonobos. We conjecture that this disparity may be a consequence of sexual selection, augmented via selection for enhanced lactation. Further, we argue that there is an organ-specific enigma similar to the Peto paradox: breast cancer risk in humans is only minimally correlated with breast size. These considerations lead to the hypothesis that, along with the evolutionary development of larger breasts in humans, additional changes have played a balancing role in suppressing breast cancer. These yet-to-be-discovered mechanisms, while purely speculative, may be valuable to understanding human breast cancer, though they may not be exclusive to the mammary gland epithelial cells. Combining these themes, we review some anti-carcinogenesis preventive strategies and prospects of new interventions against breast cancer.

A Review of Anthropometric Measurements for Saudi Adults and Elderly, Directions for Future Work and Recommendations to Establish Saudi Guidelines in Line with the Saudi 2030 Vision

Body weight is a significant risk factor for the disease burden of noncommunicable diseases (NCDs). Anthropometric measurements are the first step in determining NCDs risk, and clinicians must have access to valid cutoffs. This study aims to review the literature of Saudi national guidelines and studies previously conducted in Saudi Arabia (SA) and to provide insights and recommendations to establish national guidelines in anthropometric measurements for Saudi adults/elderly in line with the Saudi 2030 Vision. In total, 163 studies were included, and 12 of them contributed to the development of specific anthropometric cutoffs. Cutoffs for metabolic syndrome, waist circumference, and body mass index were established in Saudi adults. However, limited studies were conducted in the elderly. This review warrants establishing standard cutoffs of Saudi adult anthropometrics to avoid over/underreporting of malnutrition and adiposity. This review will help policymakers and the Ministry of Health to establish national guidelines and standard cutoffs to be used in SA for anthropometric measurements that may assist in detecting malnutrition and NCDs.

Progesterone from ovulatory menstrual cycles is an important cause of breast cancer

Many factors, including reproductive hormones, have been linked to a woman's risk of developing breast cancer (BC). We reviewed the literature regarding the relationship between ovulatory menstrual cycles (MCs) and BC risk. Physiological variations in the frequency of MCs and interference with MCs through genetic variations, pathological conditions and or pharmaceutical interventions revealed a strong link between BC risk and the lifetime number of MCs. A substantial reduction in BC risk is observed in situations without MCs. In genetic or transgender situations with normal female breasts and estrogens, but no progesterone (P4), the incidence of BC is very low, suggesting an essential role of P4. During the MC, P4 has a strong proliferative effect on normal breast epithelium, whereas estradiol (E2) has only a minimal effect. The origin of BC has been strongly linked to proliferation associated DNA replication errors, and the repeated stimulation of the breast epithelium by P4 with each MC is likely to impact the epithelial mutational burden. Long-lived cells, such as stem cells, present in the breast epithelium, can carry mutations forward for an extended period of time, and studies show that breast tumors tend to take decades to develop before detection. We therefore postulate that P4 is an important factor in a woman's lifetime risk of developing BC, and that breast tumors arising during hormonal contraception or after menopause, with or without menopausal hormone therapy, are the consequence of the outgrowth of pre-existing neoplastic lesions, eventually stimulated by estrogens and some progestins.

A propensity score-matched analysis of breast-conserving surgery plus whole-breast irradiation versus mastectomy in breast cancer

PURPOSE

Recent observations regarding long-term outcomes among patients with early-stage breast cancer (BC) who underwent breast-conserving surgery (BCS) plus whole-breast irradiation (WBI) or mastectomy are from a small number of registry-based studies. Therefore, these findings may overestimate differences in survival between the two groups, compared with randomized controlled trials conducted in the 1980s. The aim of this study is to compare long-term outcomes and clinicopathologic characteristics between patients treated with BCS + WBI or mastectomy for BC.

METHODS

We performed a propensity score-matched analysis in a cohort of 9710 patients aged < 70 years who underwent BCS + WBI or mastectomy without external radiotherapy for a first primary BC (pT1-2, N0-3a) at the European Institute of Oncology between 2000 and 2008. Patients were matched by propensity score.

RESULTS

Median follow-up was 8.4 years (interquartile range 6.5-10.2). The cumulative incidence of axillary lymph node recurrence at 10 years was lower in the BCS + WBI group [2.4% (95% CI, 1.7-3.3%)] than in the mastectomy group [4.4% (95% CI, 3.5-5.5%)] (P = .0005), and the cumulative incidence of contralateral BC was higher in the BCS + WBI group [3.9% (95% CI, 2.8-5.1%)] than in the mastectomy group [2.5% (95% CI, 1.7-3.4%)] (P = .01). Among the 366 patients with HER2 subtype BC, BCS + WBI was associated with a fivefold higher risk [hazard ratio 4.97 (95% CI, 2.28-10.8)] of  ipsilateral breast tumor recurrence (IBTR), compared with mastectomy (P < .0001); however, among patients with other BC subtypes, the rates of IBTR were not statistically significantly different.

CONCLUSION

Patients with HER2 subtype BC (T1-2, N0-3) who underwent BCS + WBI had a statistically significantly higher risk of IBTR than patients who underwent mastectomy. Survival was not statistically significantly different between the groups.

The evolution of perennially enlarged breasts in women: a critical review and a novel hypothesis

The possession of permanent, adipose breasts in women is a uniquely human trait that develops during puberty, well in advance of the first pregnancy. The adaptive role and developmental pattern of this breast morphology, unusual among primates, remains an unresolved conundrum. The evolutionary origins of this trait have been the focus of many hypotheses, which variously suggest that breasts are a product of sexual selection or of natural selection due to their putative role in assisting in nursing or as a thermoregulatory organ. Alternative hypotheses assume that permanent breasts are a by-product of other evolutionary changes. We review and evaluate these hypotheses in the light of recent literature on breast morphology, physiology, phylogeny, ontogeny, sex differences, and genetics in order to highlight their strengths and flaws and to propose a coherent perspective and a new hypothesis on the evolutionary origins of perennially enlarged breasts in women. We propose that breasts appeared as early as Homo ergaster, originally as a by-product of other coincident evolutionary processes of adaptive significance. These included an increase in subcutaneous fat tissue (SFT) in response to the demands of thermoregulatory and energy storage, and of the ontogenetic development of the evolving brain. An increase in SFT triggered an increase in oestradiol levels (E2). An increase in meat in the diet of early Homo allowed for further hormonal changes, such as greater dehydroepiandrosterone (DHEA/S) synthesis, which were crucial for brain evolution. DHEA/S is also easily converted to E2 in E2-sensitive body parts, such as breasts and gluteofemoral regions, causing fat accumulation in these regions, enabling the evolution of perennially enlarged breasts. Furthermore, it is also plausible that after enlarged breasts appeared, they were co-opted for other functions, such as attracting mates and indicating biological condition. Finally, we argue that the multifold adaptive benefits of SFT increase and hormonal changes outweighed the possible costs of perennially enlarged breasts, enabling their further development.

Controllable Factors to Reduce the Rate of Complications in Primary Breast Augmentation: A Review of the Literature

BACKGROUND

Aesthetic augmentation mammoplasties are one of the most demanded procedures performed in the aesthetic surgical sector. Because of the high epidemiological impact, the evaluation of measures to reduce the risk of complications is highly needed. The goal of this review is to evaluate the current literature for successful actions to reduce the risk of complications in aesthetic breast augmentation.

METHODS

We searched Medline-listed journals for "complications primary breast augmentation" and defined surgeon-dependent and patient-dependent factors within those.

RESULTS

Most of the strategies to reduce the risk of any complication are based on meticulous hygienic precautions and adequate training of the surgeon. The current literature suggests complications such as capsular contracture, infection and BIA-ALCL are closely linked with bacterial contamination and therefore can be avoided with different hygienic measures.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Breast Cancer and Major Deviations of Genetic and Gender-related Structures and Function

We have searched the literature for information on the risk of breast cancer (BC) in relation to gender, breast development, and gonadal function in the following 8 populations: 1) females with the Turner syndrome (45, XO); 2) females and males with congenital hypogonadotropic hypogonadism and the Kallmann syndrome; 3) pure gonadal dysgenesis (PGD) in genotypic and phenotypic females and genotypic males (Swyer syndrome); 4) males with the Klinefelter syndrome (47, XXY); 5) male-to-female transgender individuals; 6) female-to-male transgender individuals; 7) genotypic males, but phenotypic females with the complete androgen insensitivity syndrome, and 8) females with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome (müllerian agenesis). Based on this search, we have drawn 3 major conclusions. First, the presence of a Y chromosome protects against the development of BC, even when female-size breasts and female-level estrogens are present. Second, without menstrual cycles, BC hardly occurs with an incidence comparable to males. There is a strong correlation between the lifetime number of menstrual cycles and the risk of BC. In our populations the BC risk in genetic females not exposed to progesterone (P4) is very low and comparable to males. Third, BC has been reported only once in genetic females with MRKH syndrome who have normal breasts and ovulating ovaries with normal levels of estrogens and P4. We hypothesize that the oncogenic glycoprotein WNT family member 4 is the link between the genetic cause of MRKH and the absence of BC women with MRKH syndrome.

Stereotypical and Actual Associations of Breast Size with Mating-Relevant Traits

Breast size varies substantially among women and influences perception of the woman by other people with regard to her attractiveness and other characteristics that are important in social contexts, including mating. The theory of sexual selection predicts that physical criteria of partner selection should be markers of the candidate's desirable properties, mainly biological quality. Few studies, however, have examined whether breast size really signals biological quality or its components and whether observers accurately interpret these signals. Our first study encompassed 163 young women and aimed to establish actual correlates of breast size. The aim of the second study was to determine preferences and stereotypes related to breast size: 252-265 women and men evaluated female digital figures varying in, among other characteristics, breast size. Breast size (breast circumference minus chest circumference) was negatively associated with body asymmetry and positively associated with infections of the respiratory system, but did not correlate with infections of the digestive system, openness to casual sex, and testosterone and estradiol level. Women and men perceived breasts in a similar way to each other: the bigger the breasts the higher the reproductive efficiency, lactational efficiency, sexual desire, and promiscuity attributed to the woman. Nevertheless, large breasts were not regarded more attractive than average ones, though small breasts were the least attractive. In addition, big-breasted women were perceived as less faithful and less intelligent than women with average or small breasts. We discuss our results from the perspectives of evolutionary psychology, perceptual biases, and social stereotypes.

Does risk of brain cancer increase with intracranial volume? A population-based case control study

Background

Glioma is the most common primary brain tumor and is believed to arise from glial stem cells. Despite large efforts, there are limited established risk factors. It has been suggested that tissue with more stem cell divisions may exhibit higher risk of cancer due to chance alone. Assuming a positive correlation between the number of stem cell divisions in an organ and size of the same organ, we hypothesized that variation in intracranial volume, as a proxy for brain size, may be linked to risk of high-grade glioma.

Methods

Intracranial volume was calculated from pretreatment 3D T1-weighted MRI brain scans from 124 patients with high-grade glioma and 995 general population-based controls. Binomial logistic regression analyses were performed to ascertain the effect of intracranial volume and sex on the likelihood that participants had high-grade glioma.

Results

An increase in intracranial volume of 100 mL was associated with an odds ratio of high-grade glioma of 1.69 (95% CI: 1.44‒1.98; P < 0.001). After adjusting for intracranial volume, female sex emerged as a risk factor for high-grade glioma (odds ratio for male sex = 0.56, 95% CI: 0.33‒0.93; P = 0.026).

Conclusions

Intracranial volume is strongly associated with risk of high-grade glioma. After correcting for intracranial volume, risk of high-grade glioma was higher in women. The development of glioma is correlated to brain size and may to a large extent be a stochastic event related to the number of cells at risk.

Anthropometric Breast Measurement: Analysis of the Average Breast in Young Nulliparous Saudi Female Population

Anthropometric measurements and proportions of the female body play a significant role in plastic and reconstructive surgery. This study is aimed to identify the descriptive measurements of the breast in a sample population of young nulliparous Saudi women.

A Novel Level I Oncoplastic Surgery Technique for Tumors Located in UIQ of the Breast Far from the Nipple: The "Cross" Technique

Breast surgery was revolutionized with the use of oncoplastic reshaping techniques minimizing breast deformities and esthetic complications. However, the application of the current oncoplastic techniques becomes challenging in some situations such as small-size breasts and when the tumors are located in special locations of the breast, for example, upper inner quadrant. In this article, an optimized oncoplastic technique named the "Cross" technique is introduced to overcome the abovementioned problems in the surgery of breast tumors located in the upper inner quadrant far from the center of the breast. Nineteen oncoplastic surgeries were performed by the same breast surgeon. The mean diameter and weight of the excised specimens were 20 mm and 74 g. The mean age of the patients was 51 years. Clear surgical margins were obtained in all patients. There was no marked deformity in the breast after surgery. The optimized technique produced promising results in our hands when applied to a selected group of patients. Moreover, the technique was found to reduce the need for revision surgery in ptotic breasts, as the alteration in the shape of the breast undergoing surgery is not significant enough to introduce asymmetry to the breasts.

The genetic interplay between body mass index, breast size and breast cancer risk: a Mendelian randomization analysis

BACKGROUND

Evidence linking breast size to breast cancer risk has been inconsistent, and its interpretation is often hampered by confounding factors such as body mass index (BMI). Here, we used linkage disequilibrium score regression and two-sample Mendelian randomization (MR) to examine the genetic associations between BMI, breast size and breast cancer risk.

METHODS

Summary-level genotype data from 23andMe, Inc (breast size, n = 33 790), the Breast Cancer Association Consortium (breast cancer risk, n = 228 951) and the Genetic Investigation of ANthropometric Traits (BMI, n = 183 507) were used for our analyses. In assessing causal relationships, four complementary MR techniques [inverse variance weighted (IVW), weighted median, weighted mode and MR-Egger regression] were used to test the robustness of the results.

RESULTS

The genetic correlation (rg) estimated between BMI and breast size was high (rg = 0.50, P = 3.89x10-43). All MR methods provided consistent evidence that higher genetically predicted BMI was associated with larger breast size [odds ratio (ORIVW): 2.06 (1.80-2.35), P = 1.38x10-26] and lower overall breast cancer risk [ORIVW: 0.81 (0.74-0.89), P = 9.44x10-6]. No evidence of a relationship between genetically predicted breast size and breast cancer risk was found except when using the weighted median and weighted mode methods, and only with oestrogen receptor (ER)-negative risk. There was no evidence of reverse causality in any of the analyses conducted (P > 0.050).

CONCLUSION

Our findings indicate a potential positive causal association between BMI and breast size and a potential negative causal association between BMI and breast cancer risk. We found no clear evidence for a direct relationship between breast size and breast cancer risk.

Combined Breast Reduction Augmentation

BACKGROUND

Numerous methods have been designed to reduce breasts size and weight. The goal today is to not only to reduce size but also to create a pleasing shape. Breast reduction techniques do not obtain the desired upper pole fullness, and commonly recurrent ptosis develops. To improve and maintain breast shape in the late postoperative period, we combine breast reduction with implants.

METHODS

Three hundred and sixty-six patients who underwent combined breast reduction or mastopexy with implants from January 2014 to November 2017 at IM Clinic were retrospectively reviewed. We present the indications, surgical technique, and outcomes of these patients to determine the safety and efficacy of our technique.

RESULTS

No major complications were noted in an average of 2 years of follow-up (range 2 months to 4 years). Minor complications occurred in 61 patients, of whom 46 required revision surgery (12.6%). The most common tissue-related complications were dog ears (7.6%) and poor scarring (4.9%). The most common implant-related complication was capsular contracture (0.8%).

CONCLUSIONS

Breast reduction with implants is a reliable option to provide additional volume to the upper pole of the breast to improve long-term breast shape and avoid ptosis recurrence. Our study indicates that the procedure is safe and has complication and revision rates comparable to traditional breast reduction or augmentation mastopexy techniques.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Size matters: height, cell number and a person's risk of cancer

The multistage model of carcinogenesis predicts cancer risk will increase with tissue size, since more cells provide more targets for oncogenic somatic mutation. However, this increase is not seen among mammal species of different sizes (Peto's paradox), a paradox argued to be due to larger species evolving added cancer suppression. If this explanation is correct, the cell number effect is still expected within species. Consistent with this, the hazard ratio for overall cancer risk per 10 cm increase in human height (HR₁₀) is about 1.1, indicating a 10% increase in cancer risk per 10 cm; however, an alternative explanation invokes an indirect effect of height, with factors that increase cancer risk independently increasing adult height. The data from four large-scale surveillance projects on 23 cancer categories were tested against quantitative predictions of the cell-number hypothesis, predictions that were accurately supported. For overall cancer risk the HR₁₀ predicted versus observed was 1.13 versus 1.12 for women and 1.11 versus 1.09 for men, suggesting that cell number variation provides a null hypothesis for assessing height effects. Melanoma showed an unexpectedly strong relationship to height, indicating an additional effect, perhaps due to an increasing cell division rate mediated through increasing IGF-I with height. Similarly, only about one-third of the higher incidence of non-reproductive cancers in men versus women can be explained by cell number. The cancer risks of obesity are not correlated with effects of height, consistent with different primary causation. The direct effect of height on cancer risk suggests caution in identifying height-related SNPs as cancer causing.

Everolimus inhibits breast cancer cell growth through PI3K/AKT/mTOR signaling pathway

Breast cancer is one of the most prevalent malignancies and the leading cause of cancer‑associated mortality in women worldwide and in China. Everolimus (C53H83NO14) is an efficient anti-cancer drug for breast cancer which targets mammalian target of rapamycin (mTOR). The present study investigated the inhibitory effects of everolimus on breast cancer cells and an MCF‑7‑bearing mouse model. The potential mechanism of the everolimus‑mediated decrease in growth and aggressiveness of breast cancer cells was reported. Results demonstrated that everolimus significantly inhibited breast cancer cell growth, migration and invasion. It was demonstrated that everolimus induced apoptosis through decreasing B cell lymphoma (Bcl)‑2 and Bcl‑w and increasing caspase‑3 and caspase‑8 expression levels in breast cancer cells. It was observed that everolimus decreased phosphoinositide 3‑kinase (PI3K), protein kinase B (AKT) and mTOR expression levels in breast cancer cells. Results additionally demonstrated that PI3 K overexpression prevented that everolimus‑mediated inhibition of growth and aggressiveness in MCF‑7 cells. In vivo assays demonstrated that everolimus treatment markedly inhibited tumor growth in the MCF‑7 bearing mouse model. Overall, these data indicate that everolimus inhibits growth and aggressiveness of breast cancer cells through the PI3K/AKT/mTOR signaling pathways, suggesting the PI3K/AKT/mTOR signaling pathway may act as a therapeutic target for the treatment of human cancer.

Determinants of breast size in Asian women

Breast size as a risk factor of breast cancer has been studied extensively with inconclusive results. Here we examined the associations between breast size and breast cancer risk factors in 24,353 Asian women aged 50 to 64 years old enrolled in a nationwide mammography screening project conducted between October 1994 and February 1997. Information on demographic and reproductive factors was obtained via a questionnaire. Breast size was ascertained as bust line measured at study recruitment and total breast area measured from a mammogram. The average bust line and total breast area was 91.2 cm and 102.3 cm², respectively. The two breast measurements were moderately correlated (Spearman correlation coefficient = 0.65). Age, BMI, marital and working status were independently associated with bust line and total breast area. In the multivariable analyses, the most pronounced effects were observed for BMI (24.2 cm difference in bust line and 39.4 cm² in breast area comparing women with BMI ≥30 kg/m² to BMI <20 kg/m²). Ethnicity was a positive predictor for total breast area, but not bust line.

Non-randomness of the anatomical distribution of tumors

Background

Why does a tumor start where it does within an organ? Location is traditionally viewed as a random event, yet the statistics of the location of tumors argues against this being a random occurrence. There are numerous examples including that of breast cancer. More than half of invasive breast cancer tumors start in the upper outer quadrant of the breast near the armpit, even though it is estimated that only 35 to 40% of breast tissue is in this quadrant. This suggests that there is an unknown microenvironmental factor that significantly increases the risk of cancer in a spatial manner and that is not solely due to genes or toxins. We hypothesize that tumors are more prone to form in healthy tissue at microvascular ‘hot spots’ where there is a high local concentration of microvessels providing an increased blood flow that ensures an ample supply of oxygen, nutrients, and receptors for growth factors that promote the generation of new blood vessels.

Results

To show the plausibility of our hypothesis, we calculated the fractional probability that there is at least one microvascular hot spot in each region of the breast assuming a Poisson distribution of microvessels in two-dimensional cross sections of breast tissue. We modulated the microvessel density in various regions of the breast according to the total hemoglobin concentration measured by near infrared diffuse optical spectroscopy in different regions of the breast. Defining a hot spot to be a circle of radius 200 μm with at least 5 microvessels, and using a previously measured mean microvessel density of 1 microvessel/mm², we find good agreement of the fractional probability of at least one hot spot in different regions of the breast with the observed invasive tumor occurrence. However, there is no reason to believe that the microvascular distribution obeys a Poisson distribution.

Conclusions

The spatial location of a tumor in an organ is not entirely random, indicating an unknown risk factor. Much work needs to be done to understand why a tumor occurs where it does.

Electronic supplementary material

The online version of this article (10.1186/s41236-017-0006-7) contains supplementary material, which is available to authorized users.

Adipocytes promote malignant growth of breast tumours with monocarboxylate transporter 2 expression via β-hydroxybutyrate

Adipocytes are the most abundant stromal partners in breast tissue. However, the crosstalk between breast cancer cells and adipocytes has been given less attention compared to cancer-associated fibroblasts. Here we find, through systematic screening, that primary mammary gland-derived adipocytes (MGDAs) promote growth of breast cancer cells that express monocarboxylate transporter 2 (MCT2) both in vitro and in vivo. We show that β-hydroxybutyrate is secreted by MGDAs and is required to enhance breast cancer cells malignancy in vitro. Consistently, β-hydroxybutyrate is sufficient to promote tumorigenesis of a mouse xenograft model of MCT2-expressing breast cancer cells. Mechanistically we observe that upon co-culturing with MGDAs or treatment with β-hydroxybutyrate, breast cancer cells expressing MCT2 increase the global histone H3K9 acetylation and upregulate several tumour-promoting genes. These results suggest that adipocytes promote malignancy of MCT2-expressing breast cancer via β-hydroxybutyrate potentially by inducing the epigenetic upregulation of tumour-promoting genes.

Invasion of the adipose tissue correlates with poor prognosis in breast cancer. Here, the authors show that mammary gland adipocytes promote malignancy via β-hydroxybutyrate, which acts on cancer cells through the monocarboxylate transporter MCT2 resulting in tumour-promoting epigenetic modifications.

Establishment and Clinical Application of an Electronic Database for Breast Cancer in China

PURPOSE

To establish a database for breast cancer patients to save and manage clinical data and to preliminarily investigate its clinical application.

MATERIALS AND METHODS

Information on breast cancer patients hospitalized in our department from 2008.01 to 2013.01 were input into our breast cancer management system. SPSS 16.0 software was used as a convenient reference to evaluate the accuracy of the newly built database.

RESULTS

A database of 2403 breast cancer patients was successfully established. Information in the database clearly displayed capabilities of storage, addition, retrieval, statistical analysis and other functions. As the continuously updated database showed, the distribution of age, sex, nationality, allergy history, pausimenia and marriage of patients was identical to that achieved by SPSS analysis, indicating reliable and accurate data analysis.

CONCLUSIONS

The described database is easy and convenient to operate and manage, and should prove suitable for application in clinical research and treatment.

The tumor-to-breast volume ratio (TBR) predicts cancer-specific survival in breast cancer patients who underwent modified radical mastectomy

Breast cancer is the most common cancer in women globally, and tumor size measured as the largest diameter of the tumor focus is currently used in tumor-lymph node-metastasis (TNM) staging for prognosis and treatment decisions. The present study utilized the tumor-to-breast volume ratio (TBR) to evaluate the relative tumor size and determined the prognostic impact of TBR on survival in patients with breast cancer. Two thousand twenty-five consecutive breast cancer patients who underwent modified radical mastectomy between January 2002 and December 2008 at Sun Yat-Sen University Cancer Center were enrolled in this retrospective study. Kaplan-Meier analysis was used to assess the prognostic effect of TBR on cancer-specific survival (CSS), and univariate log-rank test and multivariate Cox proportional hazards regression model were performed to identify independent prognostic factors. The optimal cutoff value of TBR was determined to be 1.70 %, and 1473 and 552 patients were categorized to low-TBR and high-TBR groups, respectively. In the whole patient cohort, CSS was significantly shorter in the high-TBR group (110.2 vs 128.5 months, P < 0.001). Univariate and multivariate analyses revealed that TBR was an independent prognostic factor of CSS in breast cancer patients (hazard ratio (HR) 1.489, 95 % CI 1.130-1.961, P = 0.005). High TBR was independently associated with poor prognosis in breast cancer patients. This variable may serve as a valuable parameter to predict the outcomes of breast cancer.

Breast Volume Asymmetry Value, Ratio, and Cancer Risk

AIM

The aim of this study was to investigate the criteria for determining the cancer risk of the breast asymmetry by comparing breast volume asymmetry levels between healthy women and women with cancer.

MATERIALS AND METHODS

Two hundred and one women with breast cancer (group 1) were compared with 446 healthy women (group 2) who had no pathologic findings in breast sonography and mammograpy repeated with one-year interval. Data were evaluated retrospectively. Each breast volume was measured twice by Grossman-Roudner Discs. The mean value has been recorded. The amounts of volume difference between two breasts (asymmetry value) and the rates of the volume difference to the breast volume of the smaller side (asymmetry ratio) were compared in both groups.

RESULTS

There was a statistically significant difference between two groups with regard to average age and body mass index (P < 0.01). This significance was decreased but not disappeared, when the comparison was made within the 40-69 age group (P > 0.01). The rate of cases with asymmetry value over 50 mL was significantly higher in the cancer group (P = 0.029). Unfortunately, it disappeared in the 40-69 age group (P = 0.201). The breast volume asymmetry ratio over 20% was significantly higher in the cancer group both in all ages and in the 40-69 age group (P < 0.01). Odds ratio was 2.18 in the entire (all) series and 2.01 in the 40-69 age group. Moreover, there was no significant difference with regard to the rate of tumor location between the smaller or larger side of breast.

CONCLUSION

Our data show that there is a positive correlation between breast asymmetry ratio over 20% and breast cancer risk. These results need to be confirmed by prospective randomized controlled trials.

Anthropometric Measurements Usage in Medical Sciences

Morphometry is introduced as quantitative approach to seek information concerning variations and changes in the forms of organisms that described the relationship between the human body and disease. Scientists of all civilization, who existed until today, examined the human body using anthropometric methods. For these reasons, anthropometric data are used in many contexts to screen for or monitor disease. Anthropometry, a branch of morphometry, is the study of the size and shape of the components of biological forms and their variations in populations. Morphometrics can also be defined as the quantitative analysis of biological forms. The field has developed rapidly over the last two decades to the extent that we now distinguish between traditional morphometrics and the more recent geometric morphometrics. Advances in imaging technology have resulted in the protection of a greater amount of morphological information and have permitted the analysis of this information. The oldest and most commonly used of these methods is radiography. With developments in this area, CT and MRI have also been started to be used in screening of the internal organs. Morphometric measurements that are used in medicine, are widely used in the diagnosis and the follow-up and the treatment of the disease, today. In addition, in cosmetology use of these new measurements is increasing every day.