Risk factors for breast cancer in a cohort of mammographic screening program: a nested case-control study within the FRiCaM study

Unraveling the causal links and novel molecular classification of Crohn's disease in breast Cancer: a two-sample mendelian randomization and transcriptome analysis with prognostic modeling

BACKGROUND

Crohn's disease (CD), a prominent manifestation of chronic gastrointestinal inflammation, and breast cancer (BC), seemingly disparate in the medical domain, exhibit a shared characteristic. This convergence arises from their involvement in chronic inflammation and immune responses, an aspect that has progressively captivated the attention of investigators but remain controversial.

METHODS

We used two-sample Mendelian Randomization (MR) and transcriptomics to explore the relationship between CD and BC. MR assessed causality of CD on different BC subtypes and reverse causality of BC on CD. We identified CD-related differentially expressed genes and their prognostic impact on BC, and developed a new molecular BC classification based on these key genes.

RESULTS

MR revealed a causal link between CD and increased BC risk, especially in estrogen receptor-positive (ER+) patients, but not in ER-negative (ER-) cases. BC showed no causal effect on CD. Transcriptomics pinpointed genes like B4GALNT2 and FGF19 that affected BC prognosis in CD patients. A nomogram based on these genes predicted BC outcomes with high accuracy. Using these genes, a new molecular classification of BC patients was proposed.

CONCLUSIONS

CD is a risk factor for ER + BC but not for ER- BC. BC does not causally affect CD. Our prognostic model and new BC molecular classifications offer insights for personalized treatment strategies.

Healthy Lifestyle and Cancer Risk: Modifiable Risk Factors to Prevent Cancer

Cancer has become a serious problem worldwide, as it represents the main cause of death, and its incidence has increased over the years. A potential strategy to counter the growing spread of various forms of cancer is the adoption of prevention strategies, in particular, the use of healthy lifestyles, such as maintaining a healthy weight, following a healthy diet; being physically active; avoiding smoking, alcohol consumption, and sun exposure; and vitamin D supplementation. These modifiable risk factors are associated with this disease, contributing to its development, progression, and severity. This review evaluates the relationship between potentially modifiable risk factors and overall cancer development, specifically breast, colorectal, and prostate cancer, and highlights updated recommendations on cancer prevention. The results of numerous clinical and epidemiological studies clearly show the influence of lifestyles on the development and prevention of cancer. An incorrect diet, composed mainly of saturated fats and processed products, resulting in increased body weight, combined with physical inactivity, alcohol consumption, and smoking, has induced an increase in the incidence of all three types of cancer under study. Given the importance of adopting correct and healthy lifestyles to prevent cancer, global institutions should develop strategies and environments that encourage individuals to adopt healthy and regular behaviors.

Long Follow-Up Times Weaken Observational Diet-Cancer Study Outcomes: Evidence from Studies of Meat and Cancer Risk

For years, prospective cohort studies of diet and cancer incidence have reported smaller effects than do retrospective case-control (CC) studies. The differences have been attributed to problems with CC studies, including dietary recall bias, poor matching of cases and controls, and confounding. The hypothesis evaluated here is that long follow-up periods between ascertainment of diet and cancer incidence weaken the findings. Prospective studies of cancer incidence with respect to serum 25-hydroxyvitamin D concentration have already shown reduced benefit of higher concentrations for longer follow-up periods. Evaluating that hypothesis for dietary factors involved searching the journal literature for meta-analyses of red meat and processed meat and cancer incidence. I used findings from observational studies for bladder, breast, colorectal, and gastric cancers. To evaluate the effect of duration of follow-up time, I used two approaches. First, I plotted the relative risks for CC studies for gastric cancer with respect to consumption of 100 g/day of red meat and for bladder cancer for 50 g/day of processed meat against the interval between the dietary data and cancer incidence. Second, I compared nested CC studies of meat and cancer incidence for five breast cancer studies and one colorectal cancer study. Both approaches yielded an inverse correlation between interval or follow-up time and relative risk. My findings strongly suggest that diet near time of cancer diagnosis is more important than for longer intervals, that results from meta-analyses should be revised when possible with appropriate adjustments for duration of follow-up, and that dietary guidelines be revised accordingly.

Crohn's disease and breast cancer: a literature review of the mechanisms and treatment

This is a literature review describes Crohn's disease (CD) concomitant with breast cancer and summarizes possible common pathogenic mechanisms shared by the two diseases involving the IL-17 and NF-κB signaling pathways. Inflammatory cytokines including TNF-α and Th17 cells in CD patients can induce activation of the ERK1/2, NF-κB and Bcl-2 pathways. Hub genes are involved in the generation of cancer stem cells (CSCs) and are related to inflammatory mediators, including CXCL8, IL1-β and PTGS2, which promote inflammation and breast cancer growth, metastasis, and development. CD activity is highly associated with altered intestinal microbiota processes, including secretion of complex glucose polysaccharides by Ruminococcus gnavus colonies; furthermore, γ-proteobacteria and Clostridium are associated with CD recurrence and active CD, while Ruminococcaceae, Faecococcus and Vibrio desulfuris are associated with CD remission. Intestinal microbiota disorder promotes breast cancer occurrence and development. Bacteroides fragilis can produce toxins that induce breast epithelial hyperplasia and breast cancer growth and metastasis. Gut microbiota regulation can also improve chemotherapy and immunotherapy efficacy in breast cancer treatment. Intestinal inflammation can affects the brain through the brain-gut axis, which activates the hypothalamic‒pituitary‒adrenal (HPA) axis to induce anxiety and depression in patients; these effects can inhibit the antitumor immune responses of the immune system and promote breast cancer occurrence in patients with CD. There are few studies on the treatment of patients with CD concomitant with breast cancer, but published studies show three main strategies: new biological agents combined with breast cancer treatment methods, intestinal fecal bacteria transplantation, and dietary treatment.

Cross-attention multi-branch CNN using DCE-MRI to classify breast cancer molecular subtypes

Purpose

The aim of this study is to improve the accuracy of classifying luminal or non-luminal subtypes of breast cancer by using computer algorithms based on DCE-MRI, and to validate the diagnostic efficacy of the model by considering the patient's age of menarche and nodule size.

Methods

DCE-MRI images of patients with non-specific invasive breast cancer admitted to the Second Affiliated Hospital of Dalian Medical University were collected. There were 160 cases in total, with 84 cases of luminal type (luminal A and luminal B and 76 cases of non-luminal type (HER 2 overexpressing and triple negative). Patients were grouped according to thresholds of nodule sizes of 20 mm and age at menarche of 14 years. A cross-attention multi-branch net CAMBNET) was proposed based on the dataset to predict the molecular subtypes of breast cancer. Diagnostic performance was assessed by accuracy, sensitivity, specificity, F1 and area under the ROC curve (AUC). And the model is visualized with Grad-CAM.

Results

Several classical deep learning models were included for diagnostic performance comparison. Using 5-fold cross-validation on the test dataset, all the results of CAMBNET are significantly higher than the compared deep learning models. The average prediction recall, accuracy, precision, and AUC for luminal and non-luminal types of the dataset were 89.11%, 88.44%, 88.52%, and 96.10%, respectively. For patients with tumor size <20 mm, the CAMBNET had AUC of 83.45% and ACC of 90.29% for detecting triple-negative breast cancer. When classifying luminal from non-luminal subtypes for patients with age at menarche years, our CAMBNET model achieved an ACC of 92.37%, precision of 92.42%, recall of 93.33%, F1of 92.33%, and AUC of 99.95%.

Conclusions

The CAMBNET can be applied in molecular subtype classification of breasts. For patients with menarche at 14 years old, our model can yield more accurate results when classifying luminal and non-luminal subtypes. For patients with tumor sizes ≤20 mm, our model can yield more accurate result in detecting triple-negative breast cancer to improve patient prognosis and survival.

Cellular and molecular insights into the roles of visfatin in breast cancer cells plasticity programs

Obesity has reached a pandemic proportion and is responsible for the augmentation of multimorbidity including certain cancers. With the rise in obesity amongst the female population globally, a concomitant increase in breast cancer (BC) incidence and related mortality has been observed. In the present review, we have elucidated the cellular and molecular insight into the visfatin-mediated cellular plasticity programs such as Epithelial to mesenchymal transition (EMT) and Endothelial to mesenchymal transition (EndoMT), and stemness-associated changes in BC cells. EMT and EndoMT are responsible for inducing metastasis in cancer cells and conferring chemotherapy resistance, immune escape, and infinite growth potential. Visfatin, an obesity-associated adipokine implicated in metabolic syndrome, has emerged as a central player in BC pathogenesis. Several studies have indicated the presence of visfatin in the tumor microenvironment (TME) where it augments EMT and EndoMT of BC cells. Further, Visfatin also modulates the TME by acting on the tumor stroma cells such as adipocytes, infiltrated immune cells, and adipose-associated stem cells that secrete factors such as cytokines, and extracellular vesicles responsible for augmenting cellular plasticity program. Visfatin induced altered metabolism of the cancer cells and molecular determinants such as non-coding RNAs involved in EMT and EndoMT have been discussed. We have also highlighted specific therapeutic targets that can be exploited for the development of effective BC treatment. Taken together, these advanced understandings of cellular and molecular insight into the visfatin-mediated cellular plasticity programs may stimulate the development of better approaches for the prevention and therapy of BC, especially in obese patients.

Divide and Conquer: Isolating Cell Populations to Investigate How Breast Cancer Risk Factors Alter the Breast Microenvironment

Breast cancer is a multifactorial disease with risk factors that are fixed or modifiable. Understanding how these risk factors interact within breast tissue may provide insight into how to improve interventions or chemoprevention strategies to reduce breast cancer incidence. Here we describe methods to utilize breast tissue from patients with defined risk factors undergoing reduction mammoplasty or prophylactic mastectomy to isolate epithelial cells, stromal cells, adipocytes, and macrophages to investigate how risk factors impact distinct cell populations within breast tissue. Following enzymatic digestion of breast tissue, adipocyte-enriched, stromal cell, and epithelial organoid fractions can be isolated. Using antibody-conjugated beads, further cell populations, such as macrophages, can be isolated for molecular analysis. These methods can be adapted to sequentially isolate other cell populations based on specific cell surface markers and are useful for small-sized breast tissue specimens.

Gestational breast cancer in a patient with Crohn's disease: two case reports

Background

Diagnosis of breast cancer during gestation is a rare occurrence. In addition, the diagnosis of breast cancer in a patient with Crohn’s disease is not common. We present a rare case of gestational breast cancer in a patient with Crohn’s disease, with a concurrent breast cancer diagnosis in her sister.

Case presentation

A 31-year-old Syrian woman with Crohn’s disease was diagnosed with breast cancer at 30 weeks gestation; she received neoadjuvant chemotherapy during gestation. Incidentally, her 37-year-old sister was also diagnosed concomitantly with breast cancer. Both sisters underwent and successfully completed surgery and adjuvant therapy. At a 5-year review, both patients showed no signs of recurrence. The Crohn’s disease symptoms have also improved after chemotherapy, and the baby born after gestational chemotherapy is currently 5 years old with normal psychomotor development and without any congenital malformations.

Conclusions

This case report highlights the impact of gestation on breast cancer outcomes, the possibility of giving chemotherapy during gestation, and the effect of chemotherapy on the symptoms of Crohn’s disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13256-021-03224-3.

Breast cancer glycan biomarkers: their link to tumour cell metabolism and their perspectives in clinical practice

INTRODUCTION

Breast cancer (BCa) is the most common cancer type diagnosed in women and 5^th most common cause of deaths among all cancer deaths despite the fact that screening program is at place. This is why novel diagnostics approaches are needed in order to decrease number of BCa cases and disease mortality.

AREAS COVERED

In this review paper, we aim to cover some basic aspects regarding cellular metabolism and signalling in BCa behind altered glycosylation. We also discuss novel exciting discoveries regarding glycan-based analysis, which can provide useful information for better understanding of the disease. The final part deals with clinical usefulness of glycan-based biomarkers and the clinical performance of such biomarkers is compared to already approved BCa biomarkers and diagnostic tools based on imaging.

EXPERT OPINION

Recent discoveries suggest that glycan-based biomarkers offer high accuracy for possible BCa diagnostics in blood, but also for better monitoring and management of BCa patients. The review article was written using Web of Science search engine to include articles published between 2019 and 2021.

Identification of women at risk of hereditary breast-ovarian cancer among participants in a population-based breast cancer screening

Women attending mammography screening may benefit from family history (FH) assessment for the identification of Hereditary Breast Ovarian Cancer (HBOC). Few studies explored the efficacy of tailored educational interventions in driving the attention on FH-associated risk among these women. To compare the efficacy of two educational tools in increasing attention towards FH, 6.802 women with a negative mammography were randomized to receive a note on FH of breast/ovarian cancer (letter A, n = 3.402) or a note with details on possible implication of FH patterns (letter B, n = 3.200). Upon women's request, a brief questionnaire was administered on phone at the Screening Unit (S.U.) to select those eligible for an in-depth FH evaluation at the Genetic Unit (G.U.). Each affected relative was scored 1-3 according to type of cancer, age at diagnosis, gender, position in the family tree. In all, 401 women contacted the S.U.: 244 (6.6%) in group A and 177 (5.2%) in group B (adjOR 1.27; 95%CI 1.03-1.56). FH scored ≥ 3 for 164 women: 177 (47.5%) in group B and 224 (35.7%) in group A, (adjOR 1.59, 95%CI 1.06-2.38). The G.U. traced and interviewed 148 women, 65 (43.9%) were offered an in-person consultation: 38 attended and 30 were eligible for testing. A test was performed for 24 women: no BRCA pathogenic variant was found. Among mammographic screening attendees, educational material with a simple description of FH may improve self-referral of women deserving an in-depth evaluation for HBOC identification. Additional educational efforts are needed to enhance the efficiency of the intervention.

Consumption of red meat and processed meat and cancer incidence: a systematic review and meta-analysis of prospective studies

Red meat and processed meat consumption has been hypothesized to increase risk of cancer, but the evidence is inconsistent. We performed a systematic review and meta-analysis of prospective studies to summarize the evidence of associations between consumption of red meat (unprocessed), processed meat, and total red and processed meat with the incidence of various cancer types. We searched in MEDLINE and EMBASE databases through December 2020. Using a random-effect meta-analysis, we calculated the pooled relative risk (RR) and 95% confidence intervals (CI) of the highest versus the lowest category of red meat, processed meat, and total red and processed meat consumption in relation to incidence of various cancers. We identified 148 published articles. Red meat consumption was significantly associated with greater risk of breast cancer (RR = 1.09; 95% CI = 1.03-1.15), endometrial cancer (RR = 1.25; 95% CI = 1.01-1.56), colorectal cancer (RR = 1.10; 95% CI = 1.03-1.17), colon cancer (RR = 1.17; 95% CI = 1.09-1.25), rectal cancer (RR = 1.22; 95% CI = 1.01-1.46), lung cancer (RR = 1.26; 95% CI = 1.09-1.44), and hepatocellular carcinoma (RR = 1.22; 95% CI = 1.01-1.46). Processed meat consumption was significantly associated with a 6% greater breast cancer risk, an 18% greater colorectal cancer risk, a 21% greater colon cancer risk, a 22% greater rectal cancer risk, and a 12% greater lung cancer risk. Total red and processed meat consumption was significantly associated with greater risk of colorectal cancer (RR = 1.17; 95% CI = 1.08-1.26), colon cancer (RR = 1.21; 95% CI = 1.09-1.34), rectal cancer (RR = 1.26; 95% CI = 1.09-1.45), lung cancer (RR = 1.20; 95% CI = 1.09-1.33), and renal cell cancer (RR = 1.19; 95% CI = 1.04-1.37). This comprehensive systematic review and meta-analysis study showed that high red meat intake was positively associated with risk of breast cancer, endometrial cancer, colorectal cancer, colon cancer, rectal cancer, lung cancer, and hepatocellular carcinoma, and high processed meat intake was positively associated with risk of breast, colorectal, colon, rectal, and lung cancers. Higher risk of colorectal, colon, rectal, lung, and renal cell cancers were also observed with high total red and processed meat consumption.

Fruit and vegetable consumption and incident breast cancer: a systematic review and meta-analysis of prospective studies

BACKGROUND

We conducted a systematic review and meta-analysis of prospective studies to clarify the relation of fruit and vegetable consumption with incident breast cancer.

METHODS

We searched systematically PubMed and EMBASE databases up to November 2020 to include prospective studies that reported the association of fruit and vegetable consumption with incident breast cancer. The pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated for the highest versus the lowest category of total fruit and vegetable, total fruit and total vegetable consumption, as well as fruit juice and subgroups of vegetables in relation to breast cancer incidence, using a random-effect model.

RESULTS

Total fruit and vegetable consumption was associated with lower overall (RR = 0.91, 95% CI = 0.87-0.95) and postmenopausal breast cancer risk (RR = 0.88, 95% CI = 0.79-0.99). Total fruit consumption was associated with lower overall (RR = 0.93, 95% CI = 0.88-0.99) and postmenopausal breast cancer risk (RR = 0.93, 95% CI = 0.87-0.99). Total fruit and vegetable intake were associated with 11% and 26% lower risk of oestrogen- and progesterone-receptor-positive (ER+/PR+) and -negative (ER-/PR-) breast cancer, respectively. Total vegetable consumption was associated with 27% lower risk of ER-/PR- breast cancer. Fruit juice consumption was associated with increased overall breast cancer risk (RR = 1.04, 95% CI = 1.01-1.07). We did not find significant associations for subgroups of vegetable intake and breast cancer risk.

CONCLUSIONS

These findings suggest that high total fruit and vegetable consumption are associated with reduced risk of overall, postmenopausal, ER+/PR+ and ER-/PR- breast cancer.

Association Between Smoking And Cancers Among Women: Results From The FRiCaM Multisite Cohort Study

Background: Smoking is one of the leading causes of death worldwide, and it is strongly associated with several human cancers. However, the differential effects of cigarette smoke on the development and progression of different types of cancer remain unclear, and related data are limited.

Methods: In this longitudinal cohort study conducted among 75,324 women aged 41-76 years, we aimed to evaluate the effect of exposure to tobacco smoke on cancer development. The participants completed a questionnaire assessing socio-demographic characteristics, anthropometric measures, health status, and lifestyle habits, including smoking and dietary habits; Cox proportional hazards regression modelling was used to evaluate the association between smoking and 21 different types of cancer.

Results: After a 15-year follow-up, we identified 9,487 cases of cancer through record linkage with the Cancer Registry of Milan. Smoking was found to be positively associated with all neoplasms, with a Hazard Ratio (HR) of 1.10 (95% Confidence Interval (CI), 1.04-1.16). Regarding the specific types, we found the following associations: cancer of the oral cavity HR = 2.63 ( 95% CI 1.72-4.01]), oesophagus HR = 3.09 (95% CI 1.37-6.96), stomach HR = 1.52 (95% CI 1.10-2.11), pancreas HR = 1.69 (95% CI 1.29-2.21), larynx HR= 34.81 (95% CI 8.07-150.14), lung HR = 8.48 (95% CI 7.09-10.14), cervix uteri HR = 2.51 (95% CI 1.38-4.57), and bladder and urinary tract HR = 5.67 ( 95% CI 3.96-8.14); lymphoma HR = 1.37 (95% CI 1.03-1.83); and colorectal cancer HR = 1.30 (95% CI 1.11-1.51).

Conclusions: Our results thus demonstrate how smoke exposure increases the risk of several types of cancer. Considering the increasing prevalence of smoking among women, our results highlight the need to prioritize the development of anti-smoking campaigns targeted at women in order to contrast the evident gender inequality with respect to healthcare.

Relationship between formulaic breast volume and risk of breast cancer based on linear measurements

BACKGROUND

Whether breast volume is a risk factor for breast cancer is controversial. This study aimed to evaluate whether a significant association between breast volume and risk of breast cancer, based on linear measurements, was present by applying propensity score matching (PSM).

METHODS

The study was designed as a hospital-based case-control study. Between March 2018 and May 2019, 208 cases and 340 controls were retrospectively reviewed. Information on menarche, smoking, feeding mode, oral contraceptives, reproductive history and family history was obtained through a structured questionnaire. Breast volume was calculated using a formula based on linear measurements of breast parameters. Cox regression and PSM were used to estimate odds ratios and 95% confidence intervals for breast cancer using risk factors adjusted for potential confounders.

RESULTS

There was a significant difference in breast volume between the two groups before propensity score matching (P = 0.014). Binary logistic regression showed that the risk of breast cancer was slightly higher in the case group with larger breast volumes than in the control group(P = 0.009, OR = 1.002, 95%CI:1.000 ~ 1.003). However, there was no significant statistical difference between the two groups using an independent sample Mann-Whitney U test (P = 0.438) or conditional logistic regression (P = 0.446).

CONCLUSIONS

After PSM for potential confounding factors, there is no significant difference in breast volume estimated by BREAST-V formula between the case group and the control group. The risk of breast cancer may not be related to breast volume in Chinese women.

Distribution and predictors associated with the use of breast cancer screening services among women in 14 low-resource countries

BACKGROUND

Breast cancer is one of the leading public health problem globally, especially in low-resource countries (LRCs). Breast cancer screening (BCS) services are an effective strategy for early determining of breast cancer. Hence, it is imperative to understand the utilisation of BCS services and their correlated predictors in LRCs. This study aims to determine the distribution of predictors that significantly influence the utilisation of BCS services among women in LRCs.

METHODS

The present study used data on 140,974 women aged 40 years or over from 14 LRCs. The data came from country Demographic and Health Surveys (DHS) between 2008 and 2016. Multivariate logistic regression analysis was employed to investigate the significant predictors that influence the use of BCS services.

RESULTS

The utilisation of BCS services was 15.41%, varying from 81.10% (95% CI: 76.85-84.73%) in one European country, to 18.61% (95% CI: 18.16 to 19.06%) in Asian countries, 14.30% (95% CI: 13.67-14.96%) in American countries, and 14.29% (95% CI: 13.87-14.74%). Factors that were significantly associated to increase the use of BCS services include a higher level of education (OR = 2.48), advanced age at first birth (> 25 years) (OR = 1.65), female-headed households (OR = 1.65), access to mass media communication (OR = 1.84), health insurance coverage (OR = 1.09), urban residence (OR = 1.20) and highest socio-economic status (OR = 2.01). However, obese women shown a significantly 11% (OR = 0.89) lower use of BSC services compared to health weight women.

CONCLUSION

The utilisation of BCS services is low in many LRCs. The findings of this study will assist policymakers in identifying the factors that influence the use of BCS services. To increase the national BCS rate, more attention should be essential to under-represented clusters; in particular women who have a poor socioeconomic clusters, live in a rural community, have limited access to mass media communication, and are have a low level educational background. These factors highlight the necessity for a new country-specific emphasis of promotional campaigns, health education, and policy targeting these underrepresented groups in LRCs.

Preliminary study on identification of estrogen receptor-positive breast cancer subtypes based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) texture analysis

Background

Currently, breast cancer is divided into Luminal A, Luminal B, HER-2 overexpression (HER-2) and basal cell at genetic level. However, the differential diagnosis of estrogen receptor (ER)-positive breast cancer subtypes is rare. Therefore, we aimed to investigate the feasibility of identifying the ER-positive breast cancer subtypes based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) texture analysis.

Methods

A retrospective analysis was performed for clinical data of 51 patients with ER-positive breast invasive ductal carcinoma confirmed by surgery and pathology from January 20 to October 2018. FireVoxel texture analysis software was used to delineate the tumor boundary layer by layer. The differences in the above characteristics between Luminal A and Luminal B breast cancer were compared, and the diagnostic efficacy of statistically significant texture parameters for ER-positive breast cancer subtypes was analyzed.

Results

There were no significant differences in mean, standard deviation (SD), skewness and tumor size between Luminal A and Luminal B groups (P>0.05). The kurtosis, inhomogeneity and entropy could effectively distinguish between the two groups with statistically significant difference (P=0.001, P=0.000, and P=0.000). The area under the receiver operating characteristic (ROC) curve (AUC) of kurtosis, inhomogeneity and entropy diagnosed with malignant mass were 0.832, 0.859 and 0.891, respectively (P<0.01). In addition, the entropy was the best among the three indicators. When the entropy was ≤4.22, the sensitivity of the diagnosis Luminal B was 90.62% and the specificity was 78.95%.

Conclusions

The texture analysis features based on DCE-MRI can help to identify ER-positive breast cancer subtypes. Entropy can be the best single texture indicator.

Epidemiological characteristics of and risk factors for breast cancer in the world

AIM

Breast cancer is the most common cancer among women and one of the most important causes of death among them. This review aimed to investigate the incidence and mortality rates of breast cancer and to identify the risk factors for breast cancer in the world.

MATERIALS AND METHODS

A search was performed in PubMed, Web of Science, and Scopus databases without any time restrictions. The search keywords included the following terms: breast cancer, risk factors, incidence, and mortality and a combination of these terms. Studies published in English that referred to various aspects of breast cancer including epidemiology and risk factors were included in the study. Overall, 142 articles published in English were included in the study.

RESULTS

Based on the published studies, the incidence rate of breast cancer varies greatly with race and ethnicity and is higher in developed countries. Results of this study show that mortality rate of breast cancer is higher in less developed regions. The findings of this study demonstrated that various risk factors including demographic, reproductive, hormonal, hereditary, breast related, and lifestyle contribute to the incidence of breast cancer.

CONCLUSION

The results of this study indicated that incidence and mortality rates of breast cancer is rising, so design and implementation of screening programs and the control of risk factors seem essential.

Variability of breast surgery in women participating in breast cancer screening programs

INTRODUCTION

Currently, variability in surgical practice is a problem to be solved. The aim of this study is to describe the variability in the surgical treatment of breast cancer and to analyze the factors associated with it.

METHODS

The study population included 1057 women diagnosed with breast cancer and surgically treated. Our data were from the CaMISS retrospective cohort.

RESULTS

The mean age at diagnosis was 59.3 ± 5 years. A total of 732 patients were diagnosed through screening mammograms and 325 patients as interval cancers. The mastectomy surgery was more frequent in the tumors detected between intervals (OR=2.5; [95%CI: 1.8-3.4]), although this effect disappeared when we adjusted for the rest of the variables. The most important factor associated with performing a mastectomy was TNM: tumors in stage III-IV had an OR of 7.4 [95%CI: 3.9-13.8], increasing in adjusted OR to 21.7 [95%CI: 11.4-41.8]. Histologically, infiltrating lobular carcinoma maintains significance in adjusted OR (OR=2.5; [95%CI: 1.4-4.7]). According to the screening program, there were significant differences in surgical treatment. Program 3 presented an OR of non-conservative surgery of 4.0 [95%CI: 1.8-8.9]. This program coincided with the highest percentage of reconstruction (58.3%).

CONCLUSIONS

This study shows that, despite taking into account patient and tumor characteristics, there is great variability in the type of surgery depending on the place of diagnosis.