Predictive factors of survival time of breast cancer in kurdistan province of Iran between 2006-2014: a cox regression approach

Predictors of survival rates among breast cancer patients in Ethiopia: a systematic review and meta-analysis 2024

INTRODUCTION

Breast cancer remains the most common cancer and a leading cause of cancer-related deaths among women worldwide. In Ethiopia, the survival rate of breast cancer patients is influenced by various socio-demographic, clinical, and health system factors. This systematic review and meta-analysis aimed to identify and synthesize the predictors of survival rates among breast cancer patients in Ethiopia.

METHODS

We conducted a systematic review of observational cohort studies. The literature search was performed between August 1 and 30, 2024, using PubMed, Hinari, EMBASE, Google, Google Scholar, and Web of Science. The Newcastle Ottawa 2016 Critical Appraisal Checklist assessed methodological quality. Publication bias was evaluated using a funnel plot and Egger's test, and heterogeneity was examined with the I-squared test. Data were extracted with Microsoft Excel and analyzed using Stata 11.

RESULTS

A total of 15 articles with 6,375 study participants from six regions were included. We found that significant predictors of decreased survival rate among breast cancer patients were age (aHR 1.05, 95% CI 1.02-1.08), illiteracy (aHR 7.34, 95% CI 4.38-10.3), married (aHR 1.21, 95% CI 1.03-1.40), rural residence (aHR 1.71, 95% CI 1.06-2.36), two or more lymph node involvement (aHR 3.57, 95% CI 1.02-6.13), histological grade two or more (aHR 1.44, 95% CI 1.12-2.77), overweight (aHR 0.56, 95% CI 0.24-0.87), and having comorbidity (aHR 1.86, 95% CI 1.04-2.68).

CONCLUSION

This systematic review and meta-analysis identified several key predictors of reduced survival rates among breast cancer patients in Ethiopia, including older age, illiteracy, rural residence, involvement of two or more lymph nodes, higher histological grade, marital status, and the presence of comorbidities. Interestingly, being overweight was associated with improved survival. Health stakeholders and policymakers emphasizing public health education, managing comorbidities, and expanding access to early detection and treatment, especially in rural areas, are critical.

Population Based Survival Analysis of Females Diagnosed with Breast Cancer and Its Related Factors in Kerman Province from 2001 to 2015, Using Parametric Log-Logistic Models

Background: Breast cancer is the most common cancer among women worldwide and 14.2% of deaths in Iranian women were due to breast cancer. Objectives: The present study aimed at investigating the survival of females with breast cancer diagnosed over 14 years and its related factors in Kerman Province. Methods: This is a longitudinal study. Information about 2851 females diagnosed with breast cancer was inquired from the Cancer Registry of Kerman University of Medical Sciences from March 2001 to March 2015. Data analysis was performed by Stata 14 and SPSS 22. Results: Totally, 8511 women diagnosed with breast cancer were enrolled in this study. The median survival time among patients with grade 3 at diagnosis was 0.51 of patients with grade 1 (P = 0.016). The median survival time among patients with stage 4 at diagnosis was 0.11 of patients with stages 0 and 1 (P < 0.001). The median survival time among post-menopause patients at diagnosis was 0.65 of pre-menopause patients (P = 0.014). The median survival time among patients with secondary metastasis was 0.22 of patients without it (P < 0.001) and the median survival time among patients with hormonotherapy was 1.52 of patients without this treatment (P = 0.013). Conclusions: Early diagnosis can improve the survival of patients with breast cancer. Periodic checkups especially in menopause ages are recommended. Hormone therapy has been successful in increasing patients’ survival.

A Signature of Four Circulating microRNAs as Potential Biomarkers for Diagnosing Early-Stage Breast Cancer

Breast cancer (BC) is the most predominant type of cancer among women. The aim of this study is to find new biomarkers that can help in early detection of BC, especially for those who are too young to be screened using mammography as per guidelines. Using microRNA microarray, we previously showed dysregulation of 74 microRNAs in tumors from early BC patients as compared with normal adjacent tissues, which we were interested in studying in blood circulation. In this study, we investigated the expression of 12 microRNA (miR-21/miR-155/miR-23a/miR-130a/miR-145/miR-425-5p/miR-139-5p/miR-451/miR-195/miR-125b/miR-100, and miR-182) in the plasma of 41 newly diagnosed Lebanese BC patients with early invasive ductal carcinoma as compared with 32 healthy controls. Total RNA was extracted from plasma, and expression levels of miRNA of interest were measured using RT-qPCR followed by statistical analysis; miR-21, miR-155, miR-23a, miR-130a, miR-145, miR-425-5p, and miR-139-5p were significantly upregulated and miR-451 was significantly downregulated, in the plasma of BC patients as compared with healthy controls. The positively correlated miR-23a, miR-21, and miR-130a had a high diagnostic accuracy (86%). Importantly, the combination of miR-145/miR-425-5p/miR-139-5p/miR-130a scored the highest diagnostic accuracy of 95% with AUC = 0.97 (sensitivity 97% and specificity 91%). MicroRNAs are promising non-invasive diagnostic biomarkers for early-stage BC with the panel of miR-145/miR-425-5p/miR-139-5p/miR-130a having the highest diagnostic accuracy.

A Conditional Probability Model to Predict the Mortality in Patients With Breast Cancer: A Bayesian Network Analysis

BACKGROUND

The aim of this study was to compute the event rate of patients with breast cancer (BC) using Bayesian network (BN) structure.

METHOD

Data for 1,154 patients newly diagnosed with BC were recruited in this study during 2007 and 2016 in Iran. The database was linked to the regional death registration system and active follow-up was performed by referring to hospital information system or calling the patients. BN structure with inverse probability of censoring weighting (IPCW) approach was used to assess the relationship between event rate and underlying risk factors.

RESULTS

The median (25th, 75th percentiles) of patients' survival time was 46.8 (32.6, 69.3) months. There were 217 (18.8%) deaths from BC by the end of the study. The optimal BN structure (Akaike Information Criteria = -8743.66 and Bayesian Information Criteria = -8790.80) indicated that being male (conditional probability [CP] = 0.316), age >50 (CP = 0.215), higher grades (CP = 0.301) and lower survival times (CP = 0.566) had higher event rate. Also lobular carcinoma (CP = 0.157) and ductal carcinoma (CP = 0.178) type of morphology had lower event rate while other types (CP = 0.316) had higher.

CONCLUSIONS

The BN structure in which time was as a mediator of predictors-event relationship could be presented as the optimal tool to compute the event rate of BC. The findings could be used to identify the high risk patients and recommend for health policy making, prevention and planning for decrease the mortality in patients with BC.

Parametric survival model to identify the predictors of breast cancer mortality: An accelerated failure time approach

Background:

Breast cancer (BC) was the fifth cause of mortality worldwide in 2015 and second cause of mortality in Iran in 2012. This study aimed to explore factors associated with survival of patients with BC using parametric survival models.

Materials and Methods:

Data of 1154 patients that diagnosed with BC recorded in the East Azerbaijan population-based cancer registry database between March 2007 and March 2016. The parametric survival model with an accelerated failure time (AFT) approach was used to assess the association between sex, age, grade, and morphology with time to death.

Results:

A total of 217 (18.8%) individuals experienced death due to BC by the end of the study. Among the fitted parametric survival models including exponential, Weibull, log logistic, and log-normal models, the log-normal model was the best model with the Akaike information criterion = 1441.47 and Bayesian information criterion = 1486.93 where patients with higher ages (time ratio [TR] =0.693; 95% confidence interval [CI] = [0.531, 0.904]) and higher grades (TR = 0.350; 95% CI = [0.201, 0.608]) had significantly lower survival while the lobular carcinoma type of morphology (TR = 1.975; 95% CI = [1.049, 3.720]) had significantly higher survival.

Conclusion:

Log-normal model showed to be an optimal tool to model the survival of patients with BC in the current study. Age, grade, and morphology showed significant association with time to death in patients with BC using AFT model. This finding could be recommended for planning and health policymaking in patients with BC. However, the impact of the models used for analysis on the significance and magnitude of estimated effects should be acknowledged.

Breast Cancer Survival and Incidence: 10 Years Cancer Registry Data in the Northwest, Iran

Methods

Data were obtained from East Azerbaijan cancer registry database for the 10-year period between 2007 and 2016. Survival analysis was performed to calculate the breast cancer-specific survival proportions and mortality rates. Joinpoint trend analysis was performed to estimate the incidence trend of the cancer.

Results

A total number of 4989 patients were recorded with primary diagnosis of breast cancer. Of them, we collected follow-up data for 1335 (1309 female and 26 male). The 10-year crude mortality rate was 3.34 (per 100,000). The one-, two-, three-, five-, and ten-year breast cancer-specific survival proportions were 0.92 (95% CI 0.91-0.93), 0.88 (95% CI 0.86-0.90), 0.84 (95% CI 0.83-0.86), 0.77 (95% CI 0.74-0.80), and 0.65 (95% CI 0.60-0.70), respectively. Over the study period, the age-standardized incidence rates increased from 21.68 to 36.99 (per 100,000) with an annual percentage change of 5.5 percent. Older individuals and males patients had significantly worse survival, and patients with high-grade tumors had significantly higher risk of mortality.

Conclusion

A relatively better survival for breast cancer in East Azerbaijan, Iran, was observed compared to the overall breast cancer-specific survival proportions and mortality rates in the country. However, it is still poor compared to the developed countries indicating that inappropriate treatment modalities might have played a role on this.

Factors Affecting Long-Survival of Patients with Breast Cancer by Non-Mixture and Mixture Cure Models Using the Weibull, Log-logistic and Dagum Distributions: A Bayesian Approach

BACKGROUND

Breast cancer is a top biomedical research priority, and it is a major health problem. Therefore, the present study aimed to determine the prognostic factors of breast cancer survival using cure models.

METHODS

In this retrospective cohort analytic study, data of 140 breast cancer patients were collected from Ali Ibn Abi Taleb hospital, Rafsanjan, Southeastern Iran. Since in this study, a part of the population had long-term survival, cure models were used and evaluated using DIC index. The data were analyzed using Openbugs Software.

RESULTS

In this study, of 140 breast cancer patients, 23 (16.4%) cases died of breast cancer. Based on the findings, the Bayesian nonmixture cure model, with type I Dagum distribution, was the best fitted model. The variables of BMI, number of children, number of natural deliveries, tumor size, metastasis, consumption of canned food, tobacco use, and breastfeeding affected patients' survival based on type I Dagum distribution.

CONCLUSION

The results of the present study demonstrated that the Bayesian nonmixture cure model, with type I Dagum distribution, can be a good model to determine factors affecting the survival of patients when there is the possibility of a fraction of cure. In this study, it was found that adapting a healthy lifestyle (eg, avoiding canned foods and smoking) can improve the survival of breast cancer patients.

The Global and Regional Survival Rate of Women With Breast Cancer: A Systematic Review and Meta-analysis

Breast cancer is the most common cancer among women in the world. The aim of this study was to measure the global and regional survival rates of women with breast cancer. We searched Medline/PubMed, Web of Science, Scopus, and Google Scholar to identify cohort studies on the survival rate of women with primary invasive breast cancer until the end of June 2017. We used random effect models to estimate the pooled 1-, 3-, 5-, and 10-year survival rates. Subgroup analysis and meta-regression models were used to investigate the potential sources of heterogeneity. One hundred twenty-six studies were included in the meta-analysis. Between-study heterogeneities in the 1-, 3-, 5-, and 10-year survival rates were significantly high (all I²s > 50%; P = .001). The global 1-, 3-, 5-, and 10-year pooled survival rates in women with breast cancer were 0.92 (95% confidence interval [CI], 0.90-0.94), 0.75 (95% CI, 0.71-0.79), 0.73 (95% CI, 0.71-0.75), and 0.61% (95% CI, 0.54-0.67), respectively. Subgroup analysis revealed that survival rates varied in different World Health Organization regions, age and stage at diagnosis, year of the studies, and degree of development of countries. Meta-regression indicated that year of the study (β = 0.07; P = .002) and development of country (β = -0.1; P = .0001) were potential sources of heterogeneity. The survival rate was improved in recent decades; however, it is lower in developing regions than developed ones.

Age at diagnosis predicted survival outcome of female patients with breast cancer at a tertiary hospital in Yogyakarta, Indonesia

Introduction

Breast cancer is the most common cancer in women in Indonesia. Patients' survival depends on various factors, namely patient-, tumor-, and treatment-related factors. Survival analysis on Indonesian patients has only been reported in a few studies. This study aimed to identify the factors that are associated with five-year overall survival (OS) among patients with breast cancer at a local tertiary hospital in Indonesia.

Methods

A retrospective cohort study was conducted at Dr Sardjito Hospital, Yogyakarta. Female patients diagnosed with breast cancer between January and December 2009 were studied. Socio-demographic and clinicopathological data were collected from the medical and pathological records. The five-year OS rate was assessed using Kaplan Meier method and prognostic factors were analyzed using Cox regression.

Results

A total of 213 eligible patients with breast cancer were recruited. The five-year OS probability of the breast cancer patient was 51.07%. The majority of the patients (151, 70.9%) presented an advanced stage at the time of diagnosis. In the bi-variable analysis, cases who were younger, of a lower educational status, at a more advanced stage, with a bigger tumor size, and a central tumor location showed a worse five-year OS compared to their counterparts (p = 0.005, 0.001, 0.004, 0.011 and 0.023, respectively). In the multivariable analysis, age was an independent predictor for the OS (HR = 3.73; 95% CI = 1.0-13.6, p = 0.046).

Conclusion

The five-year OS of breast cancer patients in the local tertiary hospital was 51.07%. The patients' age at diagnosis was the only significant prognostic factor for the patients' survival.

Survival Time and Prognostic Factors for Breast Cancer among Women in North-East Peninsular Malaysia

Background:

Breast cancer is the most common malignant disease and the leading cause of cancer death among women globally. This study aimed to determine the median survival time and prognostic factors for breast cancer patients in a North-East State of Malaysia.

Methods:

This retrospective cohort study was conducted from January till April 2017 using secondary data obtained from the state’s cancer registry. All 549 cases of breast cancer diagnosed from 1st January 2007 until 31st December 2011 were selected and retrospectively followed-up until 31st December 2016. Sociodemographic and clinical information was collected to determine prognostic factors.

Results:

The average (SD) age at diagnosis was 50.4 (11.2) years, the majority of patients having Malay ethnicity (85.8%) and a histology of ductal carcinoma (81.5%). Median survival times for those presenting at stages III and IV were 50.8 (95% CI:25.34, 76.19) and 6.9 (95% CI:3.21, 10.61) months, respectively. Ethnicity (Adj. HR for Malay vs non-Malay ethnicity=2.52; 95% CI: 1.54, 4.13; p<0.001), stage at presentation (Adj. HR for Stage III vs Stage I=2.31; 95% CI: 1.57, 3.39; p<0.001 and Adj. HR for Stage IV vs Stage I=6.20; 95%CI: 4.45, 8.65; p<0.001), and history of surgical treatment (Adj. HR for patients with no surgical intervention=1.95; 95%CI: 1.52, 2.52; p<0.001) were observed to be the statistically significant prognostic factors associated with death caused by breast cancer.

Conclusion:

The median survival time among breast cancer patients in North-East State of Malaysia was short as compared to other studies. Primary and secondary prevention aimed at early diagnosis and surgical management of breast cancer, particularly among the Malay ethnic group, could improve treatment outcome.

HPK1 positive expression associated with longer overall survival in patients with estrogen receptor-positive invasive ductal carcinoma‑not otherwise specified

Hematopoietic progenitor kinase 1 (HPK1) belongs to the mitogen activated protein kinase kinase kinase kinase (MAP4K) family of serine/threonine kinases, which have been associated with the incidence and progression of a variety of gastrointestinal malignant tumors in humans. However, the potential association between HPK1 expression and breast cancer, particularly invasive ductal carcinoma-not otherwise specified (IDC-NOS) development, has not yet been examined. To address this gap, the present study aimed to evaluate HPK1 expression in IDC-NOS samples and to determine a relationship with clinical prognostic indicators, such as the expression levels of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2), as well as overall survival of the patients with IDC-NOS. HPK1 mRNA and protein expression in samples from 148 patients with IDC-NOS were detected using immunohistochemistry, western blotting and reverse transcription-quantitative polymerase chain reaction. A total of 54 out of 148 (36.5%) samples were HPK1-positive, and 100 out of 148 (67.6%) were ER-positive. Of the latter, 28% (28/100) were HPK1-positive, and a significant negative association of HPK1 expression with ER positivity was observed (P=0.002; r=−0.254). In addition, 43.2% (64/148) and 32.4% (48/100) of IDC-NOS tissues were PR- or HER2-positive, respectively; however, neither indicator correlated with HPK1 (P=0.109 and P=0.558, respectively). HPK1 expression, axillary lymph node metastasis and tumor-node-metastasis (TNM) stage were identified as independent factors of overall survival (OS) in the ER-positive group (P<0.05), and HPK1 positivity was associated with increased OS (P=0.048). HPK1 mRNA levels did not differ between IDC-NOS and normal adjacent breast tissues, whereas HPK1 protein levels were lower in IDC-NOS (P<0.05). These results suggested that HPK1 protein may be a potentially effective IDC-NOS therapeutic target.

The overall 5-year survival rate of breast cancer among Iranian women: A systematic review and meta-analysis of published studies

INTRODUCTION

Breast Cancer (BC) is the most prevalent cancer and the second leading cause of cancer-related death among Iranian women. A valid estimation of the 5-year survival rate can improve the current BC treatment programs. The present study aimed to assess the 5-year survival rate through a systematic review of published studies.

METHODS

A systematic search of Medline/PubMed, Scopus, and Science direct as well as Iranian databases was conducted to identify the original articles evaluating the 5-year survival rate of BC among women in Iran. Random effects model was used to estimate the pooled 5-year survival rate. The eligible articles were analyzed using the Stata software.

RESULTS

Our comprehensive literature search identified 11 eligible articles 2 of which were excluded due to reporting the results of a single study. The remaining 9 articles that contained 4815 women diagnosed with BC during 1991-2014 were included in the meta-analysis. The combined 5-year survival rate of BC was estimated to be 67.60%.

DISCUSSION/CONCLUSION

The survival rate of BC was relatively low in Iran compared to developed countries. Hence, more effective measures have to be taken to increase these patients' survival.

A Portal Vein Injection Model to Study Liver Metastasis of Breast Cancer

Breast cancer is the leading cause of cancer-related mortality in women worldwide. Liver metastasis is involved in upwards of 30% of cases with breast cancer metastasis, and results in poor outcomes with median survival rates of only 4.8 - 15 months. Current rodent models of breast cancer metastasis, including primary tumor cell xenograft and spontaneous tumor models, rarely metastasize to the liver. Intracardiac and intrasplenic injection models do result in liver metastases, however these models can be confounded by concomitant secondary-site metastasis, or by compromised immunity due to removal of the spleen to avoid tumor growth at the injection site. To address the need for improved liver metastasis models, a murine portal vein injection method that delivers tumor cells firstly and directly to the liver was developed. This model delivers tumor cells to the liver without complications of concurrent metastases in other organs or removal of the spleen. The optimized portal vein protocol employs small injection volumes of 5 - 10 μl, ≥ 32 gauge needles, and hemostatic gauze at the injection site to control for blood loss. The portal vein injection approach in Balb/c female mice using three syngeneic mammary tumor lines of varying metastatic potential was tested; high-metastatic 4T1 cells, moderate-metastatic D2A1 cells, and low-metastatic D2.OR cells. Concentrations of ≤ 10,000 cells/injection results in a latency of ~ 20 - 40 days for development of liver metastases with the higher metastatic 4T1 and D2A1 lines, and > 55 days for the less aggressive D2.OR line. This model represents an important tool to study breast cancer metastasis to the liver, and may be applicable to other cancers that frequently metastasize to the liver including colorectal and pancreatic adenocarcinomas.

Survival Prediction and Feature Selection in Patients with Breast Cancer Using Support Vector Regression

The Support Vector Regression (SVR) model has been broadly used for response prediction. However, few researchers have used SVR for survival analysis. In this study, a new SVR model is proposed and SVR with different kernels and the traditional Cox model are trained. The models are compared based on different performance measures. We also select the best subset of features using three feature selection methods: combination of SVR and statistical tests, univariate feature selection based on concordance index, and recursive feature elimination. The evaluations are performed using available medical datasets and also a Breast Cancer (BC) dataset consisting of 573 patients who visited the Oncology Clinic of Hamadan province in Iran. Results show that, for the BC dataset, survival time can be predicted more accurately by linear SVR than nonlinear SVR. Based on the three feature selection methods, metastasis status, progesterone receptor status, and human epidermal growth factor receptor 2 status are the best features associated to survival. Also, according to the obtained results, performance of linear and nonlinear kernels is comparable. The proposed SVR model performs similar to or slightly better than other models. Also, SVR performs similar to or better than Cox when all features are included in model.

Survival Rate of Breast Cancer in Iran: A Meta-Analysis

Background:

There has not been a general estimation about survival rates of breast cancer cases in Iran. Therefore, the present study aimed to assess survival using a meta-analysis.

Materials and Methods:

International credible databases such as Scopus, Web of Science, PubMed, Science direct and Google Scholar and Iranian databases such as Magiran, Irandoc and SID, from 1997 to 2015 were searched. All articles covering survival rate of breast cancer were entered into the study without any limits. Quality assessment of the articles and data extraction were performed by two researchers using the modified STROBE checklist, which includes 12 questions. Articles with scores greater than 8 were included in the analysis. A limitation of this meta-analysis was different methods for presenting of results in the papers surveyed.

Results:

A total of 21 articles with a sample of 12,195 people were analyzed. The one-year, three-year, five-year and ten-year survival rates of breast cancer in Iran were estimated to be 95.8% (94.6-97.0), 82.4% (79.0-85.8), 69.5% (64.5-74.5), 58.1% (39.6-76.6), respectively. The most important factors affecting survival of breast cancer were age, number of lymph nodes involved, size of the tumor and the stage of the disease.

Conclusion:

The five- and ten- year survival rates in Iran are lower than in developed countries. Conducting breast cancer screening plan support (including regular clinical examination, mammography), public training and raising awareness should be helpful in facilitating early diagnosis and increasing survival rates for Iranian women.

Survival Rates for Breast Cancer in Iranian Patients: a Meta- Analysis

BACKGROUND

Breast cancer is the most common cancer among Iranian women. Since development of the disease in Iranian women occurs relatively early, the survival rate matters considerably. In different countries, survival of breast cancer patients varies considerably. Therefore, the one-year, three-year, five-year, and ten- year survival rates for breast cancer in Iran were assessed using a meta-analysis.

MATERIALS AND METHODS

This systematic review and meta-analysis was based on valid Iranian sources including SID, MAGIRAN and IRANMEDEX, along with reliable English databases, namely, PUBMED and SCOPUS. In domestic databases, a search was conducted based on key words of breast cancer and survival rate, and in international databases, with "breast cancer" and the equivalent of "neoplasm" of Mesh Word, "survival rate" and "Iran. " Then all reviewed papers and theses which met the inclusion criteria were selected for investigation. To conduct the analysis STATA 11.2 software and random-effects models were used.

RESULTS

In 24 studies, 22,745 participants were included. The one-year, three-year, five-year and ten-year survival rates were 0.956, 0.808, 0.695 and 0.559, respectively. The minimum and maximum survival rates for 5-years were 0.48 and 0.87. The average age of the onset of the disease was 48.3.

CONCLUSIONS

As in Iran, since the onset of the disease is at low age, in spite of the relatively high survival rate as compared to other cancers, prevention and screening programs at early age for early stage diagnosis seems necessary.

Correlation between mammograghic findings and clinical/ pathologic features in women with small invasive breast carcinomas

BACKGROUND

To study the relationship between mammographic findings and clinical/pathologic features in women with 1-15mm sized invasive breast cancer.

MATERIALS AND METHODS

We investigated a consecutive series of 134 cases diagnosed in Tianjin Medical University Cancer Institute and Hospital in 2007. Mammographic findings were classified into five groups as follows :1) stellate mass without calcification; 2) non-stellate mass without calcification; 3) intermediate suspicious calcification with or without associated mass; 4) higher probability malignant calcification with or without associated mass; 5) focal asymmetry/distortion without associated calcification. Associations between mammographic and clinical/pathological features (menopause status/family history/histologic grade/lymph node status and ER/PR/HER2 status) was analyzed through logistic regression and chi square tests.

RESULTS

Compared to the stellate mass without calcification group, higher probability malignant calcification patients were associated significantly with a positive lymph node status, always presenting in patients who were non-menopausal and with a family history of carcinoma.

CONCLUSIONS

Higher probability malignant calcifications with or without associated tumor masses are associated with clinical/pathologic features of poor prognosis.

Survival time and molecular subtypes of breast cancer after radiotherapy in Thailand

BACKGROUND

Breast cancer is an important cause of death among women. One way of classifying different forms of breast cancer is by molecular features, usually in terms of the four subtypes: luminal A, luminal B, HER2-enriched, and triple negative.

OBJECTIVES

This study aimed to investigate the association between molecular subtypes and survival among breast cancer patients treated with radiotherapy.

MATERIALS AND METHODS

A retrospective cohort study was conducted. The subjects were 272 breast cancer patients who had received treatment in the radiotherapy unit at Srinagarind Hospital, Thailand, between 1 January, 1999, and 31 May, 2009. The end of the study was 1 June, 2014. Overall survival was defined as the time elapsing between initial registration at the radiotherapy unit and death or the end of the study. Survival curves were estimated by the Kaplan-Meier method, and a multivariate analysis was performed using Cox's proportional hazard regression model.

RESULTS

The patient mean age was 47.5±10.4 at the time of diagnosis. Of the 272 patients, 146 (53.7%) were classified as luminal A, 12 (4.4%) as luminal B, 30 (11.0%) as HER2-enriched, and 84 (30.9%) as triple negative. The overall survival rates at 1, 3 and 5 years were 87.1%, 68.4% and 59.2%, respectively. According to molecular subtypes, HER2-enriched patients had the lowest 5-year survival rate (30.0 %, 95%CI: 15.02-46.55). The median follow-up time was 8.37 years. In the Cox model analysis a higher risk of death was found for patients with HER2-enriched (HRadj=3.34, 95%CI:1.96-5.67), triple negative (HRadj=2.17, 95%CI: 1.44-3.27), and stage IIlB (HRadj=2.20, 95%CI: 1.16-4.17) cancers.

CONCLUSIONS

The worst survival rates were among patients classified as HER2-enriched, triple negative and at stage IIIB. Early detection and an advanced treatment modality are needed to help these patients.