Factors associated with late recurrence after completion of 5-year adjuvant tamoxifen in estrogen receptor positive breast cancer

Risk factors for late recurrence and postrelapse survival in estrogen receptor (ER)-positive, human epidermal growth factor receptor (HER) 2-negative breast cancer after 5 years of endocrine therapy

It is unclear which patients with ER-positive, HER2-negative breast cancer benefit from extended endocrine therapy beyond 5 years. Prognostic factors for late-recurring breast cancer postrelapse survival have been reported. We retrospectively analyzed data from 892 patients with ER-positive and HER2-negative invasive breast cancer who were disease-free after completing a 5-year adjuvant endocrine therapy. Patients were then classified as high-risk (positive lymph nodes, large tumor size, high tumor grade) or low-risk. High-risk patients were divided into extended endocrine therapy and stop groups. Comparisons were made using propensity score matching, and the benefits of extended endocrine therapy for high-risk patients and prognostic factors for postrelapse survival were assessed. The high- and low-risk groups comprised 444 and 448 patients, respectively. The 10-year distant disease-free survival (DDFS) rates were 96.3 % (95 % confidence interval [CI] 0.912-0.985) and 86.5 % (95 % CI 0.798-0911) in the extended and stop groups, respectively (P = 0.00382). Cox proportional hazards model revealed that extended endocrine therapy promoted greater reduction in distant metastasis risk than 5-year endocrine therapy in high-risk populations (hazard ratio [HR] 0.27; 95 % CI 0.11-0.68; P = 0.0054). Postrelapse survival was significantly different in patients with DDFS ≥7 years (HR 0.24; 95 % CI 0.072-0.81; P = 0.021) and those with better response to first-line treatment (HR 0.072; 95 % CI, 0.058-0.90; P = 0.041). Patients with risk factors for late recurrence should be considered for extended endocrine therapy. Longer DDFS and response to first-line treatment may be a prognostic factor for postrelapse survival after late recurrence.

Matrix Metalloproteinase-1 (MMP1) Upregulation through Promoter Hypomethylation Enhances Tamoxifen Resistance in Breast Cancer

Simple Summary

Cancer recurrence caused by tamoxifen resistance hampers chemotherapy in breast cancer patients. The reasons behind the resistance were investigated by screening epigenetically regulated genes through analysis of methylation data from tamoxifen-resistant MCF-7 cells. MMP1 locus was found to be hypomethylated at a promoter CpG site and its expression was upregulated in the cell line, which was verified by the drug-resistant tumor tissues from breast cancer patients (n = 28). Downregulating MMP1 using a short hairpin RNA inhibited the growth of resistant cells and increased sensitivity to tamoxifen in vitro as well as in a xenografted mouse model in vivo. This study suggests that MMP1 is potentially a target gene to control tamoxifen resistance in breast cancer.

Abstract

Background: Tamoxifen (tam) is widely used to treat estrogen-positive breast cancer. However, cancer recurrence after chemotherapy remains a major obstacle to achieve good patient prognoses. In this study, we aimed to identify genes responsible for epigenetic regulation of tam resistance in breast cancer. Methods: Methylation microarray data were analyzed to screen highly hypomethylated genes in tam resistant (tamR) breast cancer cells. Quantitative RT-PCR, Western blot analysis, and immunohistochemical staining were used to quantify expression levels of genes in cultured cells and cancer tissues. Effects of matrix metalloproteinase-1 (MMP1) expression on cancer cell growth and drug resistance were examined through colony formation assays and flow cytometry. Xenografted mice were generated to investigate the effects of MMP1 on drug resistance in vivo. Results: MMP1 was found to be hypomethylated and overexpressed in tamR MCF-7 (MCF-7/tamR) cells and in tamR breast cancer tissues. Methylation was found to be inversely associated with MMP1 expression level in breast cancer tissues, and patients with lower MMP1 expression exhibited a better prognosis for survival. Downregulating MMP1 using shRNA induced tam sensitivity in MCF-7/tamR cells along with increased apoptosis. The xenografted MCF-7/tamR cells that stably expressed short hairpin RNA (shRNA) against MMP1 exhibited retarded tumor growth compared to that in cells expressing the control shRNA, which was further suppressed by tam. Conclusions: MMP1 can be upregulated through promoter hypomethylation in tamR breast cancer, functioning as a resistance driver gene. MMP1 can be a potential target to suppress tamR to achieve better prognoses of breast cancer patients.

Evaluation of the ability of the Clinical Treatment Score at 5 years (CTS5) compared to other risk stratification methods to predict the response to an extended endocrine therapy in breast cancer patients

PURPOSE

Extension of adjuvant endocrine therapy (ET) reduces the risk of recurrence in women diagnosed with ER-positive breast cancers, but a significant benefit is unlikely to happen to all individual patients. This study is aimed at evaluating the ability of different clinical late distant recurrence (LDR) risk stratification methods and in particular the clinical treatment score at 5 years (CTS5) to predict the response to extended adjuvant ET.

METHODS

783 patients diagnosed with ER+ BC between 1988 and 2014 at Umberto I Hospital of Turin, of which 180 received an extended adjuvant ET, were retrospectively selected. They were stratified according to pT, pN, disease stage, tumor grade, Ki67 level, progesterone receptor status and CTS5. The primary endpoint was LDR rate. LDR rates according to ET duration were confronted in each subgroup.

RESULT

The median duration of extended ET was 7 years (6-10). Median follow-up from diagnosis was 9 years (6-26). Retrospective risk stratification according to tumor size, nodal status, disease stage, tumor grade, Ki67 level, and progesterone receptor status did not appear to be able to predict the response to extended ET. In the CTS5 high-risk subgroup instead, the risk of developing an LDR was significantly lower in the patients who underwent extended ET compared to standard ET (HR 0.37, 95% CI 0.15-0.91), while no significant benefit was demonstrated for low and intermediate-risk patients.

CONCLUSIONS

Risk stratification according to CTS5 appeared to be predictive of the response to extended endocrine therapy in our population of real-life pre and postmenopausal patients.

Clinical Implications of Serum 25-Hydroxyvitamin D Status after 5-Year Adjuvant Endocrine Therapy for Late Recurrence of Hormone Receptor-positive Breast Cancer

Purpose

The prognostic implications of serum vitamin D status after a 5-year adjuvant endocrine therapy on the risk of late recurrence among hormone receptor (HR)-positive breast cancer patients remain unclear. Hence, we investigated this among Korean HR-positive breast cancer patients.

Methods

A total of 455 patients with HR-positive stage I–III invasive breast cancer who underwent curative surgery at St. Vincent's Hospital between February 2004 and April 2012 were included in this retrospective study. Patients were categorized based on their serum 25-hydroxyvitamin D (25(OH)D) levels after the 5-year adjuvant endocrine therapy. Initial recurrence sites were categorized. The primary clinical outcome was late recurrence-free survival (LRFS).

Results

Among the 455 patients, 242 and 213 were included in the 25(OH)D-deficient group and 25(OH)D-sufficient group, respectively. Forty-eight patients experienced late recurrence. Across all recurrence sites, the 25(OH)D-deficient group showed significantly worse LRFS rates than the 25(OH)D-sufficient group (hazard ratio [HR], 2.284; 95% confidence interval [CI], 1.155–4.515; p = 0.018). After patient subgrouping based on recurrence site, the 25(OH)D-deficient group also showed significantly worse LRFS rates in terms of regional lymph node (LN) (HR, 17.453; 95% CI, 2.46–128.83; p = 0.005), bone (HR, 2.394; 95% CI, 1.024–5.599; p = 0.044), and visceral (HR, 2.735; 95% CI, 1.182–6.328; p = 0.019) recurrence. However, there was no significant difference between the 2 groups in terms of local recurrence (p = 0.611).

Conclusions

We found that 25(OH)D deficiency after the 5-year adjuvant endocrine therapy was associated with worse LRFS among HR-positive breast cancer patients, particularly with respect to regional LN, bone, and visceral recurrence.

CYP2D6 does not impact on breast cancer-free survival in Southeast Mexican patients under tamoxifen treatment

Aim: We conducted a retrospective analysis in 71 Mexican Mestizo patients to evaluate the breast cancer-free survival (BCFS) among the inferred genetic phenotypes (GP) of CYP2D6. Patients & methods: CYP2D6 was genotyped through Taqman-probe analysis; GP were inferred according to international guidelines. The BCFS was estimated through Kaplan–Meier method and analyzed with a log-rank test; hazard ratios were calculated with 95% CI and p < 0.05. Results: The BCFS did not differ among CYP2D6 GP (p = 0.45) and recurrence risk was similar between gNM + gUM and gPM + gIM groups (hazard ratio: 1.54, 95% CI: 0.37–6.38; p = 0.55). Conclusion: The findings do not support any impact of CYP2D6 on BCFS. Evaluation of other genetic/nongenetic biomarkers is needed in Mexican Mestizo patients under tamoxifen treatment.

Incidence and Predictors of Recurrence among Breast Cancer Patients in Black Lion Specialized Hospital Adult Oncology Unit, Addis Ababa, Ethiopia: Retrospective Follow-up Study with Survival Analysis

Currently, breast cancer is becoming a major public health problem for developing countries. In Ethiopia, breast cancer is the most prevalent cancer among women, and constitutes a major public health concern. Hence, this study was aimed to determine the incidence and predictor of recurrence among breast cancer clients at Black Lion Specialized Hospital, Ethiopia, in 2018. We analyzed 513 patients out of 835 women breast cancer patients treated at Black Lion Specialized Hospital. Recurrent-free survival was determined using the Kaplan-Meier method, with comparisons between groups through the log-rank test. The Cox proportional hazards model was used to identify predictors of recurrence among breast cancer clients. The incidence rate of recurrence among breast cancer was 6.5% per (95% CI = 6.49-12.47) follow-up. The median recurrent-free survival time was 60.33 months (95% CI = 54.46-62.30). Predictors of recurrence were negative estrogen receptor (hazard ratio [HR] = 1.8, 95% CI = 1.53-7.62), high histologic grade (HR = 2.8, 95% CI = 1.14-10.31), positive lymph node status (HR = 2.6, 95% CI = 1.14-10.31), clinical staging III (HR = 2.5, 95% CI = 1.26-9.42), and involved deep surgical margin (HR = 3.6, 95% CI = 2.14-8.61). This research showed that incidence of recurrence was high. Advanced clinical stage, positive nodal status, high histologic grade, negative estrogen receptor, and involved deep surgical margin were associated with higher recurrence rates. In contrast, hormonal therapy has a great role in decreasing the development of recurrence.

Validation of CTS5 on a Retrospective Cohort of Real-Life Pre- and Postmenopausal Patients Diagnosed With Estrogen Receptor-Positive Breast Cancers: Is It Prognostic?

BACKGROUND

More than 50% of estrogen receptor (ER)-positive breast cancer (BC) distant recurrences (DR) develop after the completion of 5 years of adjuvant endocrine therapy (ET). Its extension is beneficial on disease-free survival and overall survival but increases therapy-related side effects. Selecting patients who could benefit the most from an extended regimen has become an increasing need. Clinical Treatment Score at 5 Years (CTS5) is a prognostic tool using clinicopathologic data to estimate DR risk after 5 years of ET for ER⁺ BC. We sought to validate the prognostic value of CTS5 in a retrospective cohort of real-life pre- and postmenopausal patients diagnosed with ER⁺ BC.

PATIENTS AND METHODS

CTS5 was calculated for 603 patients diagnosed with ER⁺ BC at Umberto I Hospital of Turin and DR-free after 5 years of ET. Primary endpoint was late DR (LDR) rate.

RESULTS

Median follow-up was 8 years (range, 6-26 years). The 426 postmenopausal women were categorized by CTS5 as follows: 152 low risk, 139 intermediate risk, and 135 high risk. LDR rates were 3.9%, 7.2%, and 15.6%, respectively. CTS5 results were prognostic for LDR: patients with CTS5-high showed a fourfold risk of developing an LDR compared to patients with CTS5-low (hazard ratio, 4.48; 95% confidence interval, 1.80-11.1). The same analysis was conducted for the 177 premenopausal women: 88 low risk, 40 intermediate risk, and 49 high risk. LDR rate were 5.6%, 7.5%, and 20.4%, respectively, proving CTS5 to be prognostic for premenopausal patients as well (CTS5-high vs. CTS5-low: hazard ratio, 3.40; 95% confidence interval, 1.06-11.0).

CONCLUSION

CTS5 was shown to be prognostic of the risk of LDR in our population of real-life pre- and postmenopausal patients. Our results support its use in clinical practice to better tailor the prescription of extended ET.

Polypoid endometriosis: a mimic of malignancy

This an interesting case of an asymptomatic 60-year-old postmenopausal patient with an incidental pelvic mass mimicking a pelvic malignancy on imaging. Biopsy revealed findings consistent with polypoid endometriosis. After discontinuation of hormone replacement therapy, the mass showed decrease in size on follow-up imaging. Polypoid endometriosis is a rare but distinct variant of endometriosis with histopathologic features akin to an endometrial polyp. Clinical and imaging features of polypoid endometriosis differ from classic endometriosis. While classic endometriosis predominates in premenopausal women, polypoid endometriosis more commonly affects peri- to postmenopausal women and is associated with the exposure to Tamoxifen or hormone replacement therapy. Imaging features that aid in the diagnosis of polypoid endometriosis are a T2 hyperintense polypoid mass with signal characteristics similar to endometrium, a T2 hypointense peripheral rim, contrast enhancement pattern mirroring the enhancement of the endometrium, and lack of diffusion restriction. Radiologists should be familiar with polypoid endometriosis because this clinically and morphologically distinct variant may mimic malignant neoplasms on imaging.

Validation of CTS5 model in large-scale breast cancer population and the impact of menopausal and HER2 status on its prognostic value

Clinical Treatment Score post-5 years (CTS5) is a promising prognostic tool to evaluate late recurrence risk for breast cancer. Our study aimed to validate its prognostic value in large-scale population and explore the impact of menopausal and HER2 status on CTS5 model. We performed a retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER) database. Survival analyses were conducted to assess the prognostic value of CTS5 in different breast cancer subgroups in terms of overall survival (OS) and breast cancer specific survival (BCSS) after five years. A total of 23,168 breast cancer patients with positive hormone receptor (HoR) were enrolled. Postmenopausal and premenopausal patients were 13,686 and 9,482, respectively. Taking CTS5 score as a continuous variable, it had significant positive correlation with poor prognosis beyond five years in both postmenopausal and premenopausal subgroups. Nevertheless, for HER2+ postmenopausal patients, the model has less effective prognostic value on long-term BCSS [HR1.177 (95%CI 0.960-1.443), p = 0.117]. Using CTS5 score as a categorical variable, HER2- patients with high-risk level revealed significant poor survival in terms of both BCSS and OS, irrespective of menopausal status. Our study showed the CTS5 model could be a useful prognostic tool for predict long-term survival in HoR+/HER2- patients. And further large-scale studies are warranted to assess its prognostic value for HER2+ patients and develop novel prediction model for late recurrence risk estimation.

Prediction of Late Breast Cancer-Specific Mortality in Recurrence-Free Breast Cancer Survivors Treated for Five Years with Tamoxifen

Purpose

The extension of endocrine therapy beyond 5 years for recurrence-free survivors of breast cancer improves survival; however, the issue on how to clinically identify appropriate candidates remains controversial. This study aimed to identify prognostic factors for breast-cancer-specific mortality in patients who have had 5 years of tamoxifen treatment and categorize subgroups based on the risk of death using combinations of these prognostic factors to assist in the clinical decision to perform further endocrine therapy.

Methods

In total, 3,158 patients with breast cancer were enrolled. Breast cancer-specific survival rates after 5 years of tamoxifen treatment were calculated, and associated prognostic factors were analyzed using a Cox proportional-hazards model.

Results

An age extreme at diagnosis (i.e., < 40 or ≥ 60 years), tumor size > 2 cm, and positive lymphovascular invasion were robust independent prognostic factors for late breast cancer-specific death in tamoxifen-treated patients (hazard ratio [HR] = 2.162, 1.739, and 1.993; p = 0.001, 0.047, and 0.011, respectively). Lymph node metastasis and progesterone receptor negativity had borderline significance in this regard (HR = 1.741 and 1.638, p = 0.099 and 0.061). The study patients were classified into four groups according to the number of prognostic indicators, i.e., low, intermediate, high, and extremely high risk. The additional 5- and 10-year cumulative risks of breast cancer-specific death were 0.8% and 1.5% in the low-risk group, 0.9% and 3.9% in the intermediate-risk group, 1.3% and 7.3% in the high-risk group, and 4.8% and 13.8% in the extremely high-risk group, respectively.

Conclusion

This new risk stratification system for late mortality in breast cancer can be used to identify the right candidates for extended endocrine therapy after 5 years of tamoxifen treatment.

Preexisting Commensal Dysbiosis Is a Host-Intrinsic Regulator of Tissue Inflammation and Tumor Cell Dissemination in Hormone Receptor-Positive Breast Cancer

It is unknown why some patients with hormone receptor-positive (HR⁺) breast cancer present with more aggressive and invasive disease. Metastatic dissemination occurs early in disease and is facilitated by cross-talk between the tumor and tissue environment, suggesting that undefined host-intrinsic factors enhance early dissemination and the probability of developing metastatic disease. Here, we have identified commensal dysbiosis as a host-intrinsic factor associated with metastatic dissemination. Using a mouse model of HR⁺ mammary cancer, we demonstrate that a preestablished disruption of commensal homeostasis results in enhanced circulating tumor cells and subsequent dissemination to the tumor-draining lymph nodes and lungs. Commensal dysbiosis promoted early inflammation within the mammary gland that was sustained during HR⁺ mammary tumor progression. Furthermore, dysbiosis enhanced fibrosis and collagen deposition both systemically and locally within the tumor microenvironment and induced significant myeloid infiltration into the mammary gland and breast tumor. These effects were recapitulated both by directly targeting gut microbes using nonabsorbable antibiotics and by fecal microbiota transplantation of dysbiotic cecal contents, demonstrating the direct impact of gut dysbiosis on mammary tumor dissemination. This study identifies dysbiosis as a preexisting, host-intrinsic regulator of tissue inflammation, myeloid recruitment, fibrosis, and dissemination of tumor cells in HR⁺ breast cancer. SIGNIFICANCE: Identification of commensal dysbiosis as a host-intrinsic factor mediating evolution of metastatic breast cancer allows for development of interventions or diagnostic tools for patients at highest risk for developing metastatic disease.See related commentary by Ingman, p. 3539.

SET Overexpression is Associated with Worse Recurrence-Free Survival in Patients with Primary Breast Cancer Receiving Adjuvant Tamoxifen Treatment

Adjuvant tamoxifen reduces the recurrence rate of estrogen receptor (ER)-positive breast cancer. Previous in vitro studies have suggested that tamoxifen can affect the cancerous inhibitor of protein phosphatase 2A (CIP2A)/protein phosphatase 2A (PP2A)/phosphorylation Akt (pAkt) signaling in ER-negative breast cancer cells. In addition to CIP2A, SET nuclear proto-oncogene (SET) oncoprotein is another intrinsic inhibitor of PP2A, participating in cancer progression. In the current study, we explored the clinical significance of SET, CIP2A, PP2A, and Akt in patients with ER-positive breast cancer receiving adjuvant tamoxifen. A total of 218 primary breast cancer patients receiving adjuvant tamoxifen with a median follow-up of 106 months were analyzed, of which 17 (7.8%) experienced recurrence or metastasis. In an immunohistochemical (IHC) stain, SET overexpression was independently associated with worse recurrence-free survival (RFS) (hazard ratio = 3.72, 95% confidence interval 1.26–10.94, p = 0.017). In silico analysis revealed mRNA expressions of SET, PPP2CA, and AKT1 significantly correlated with worse RFS. In vitro, SET overexpression reduced tamoxifen-induced antitumor effects and drove luciferase activity in an Estrogen receptor element (ERE)-dependent manner. In conclusion, SET is a prognostic biomarker in patients with primary ER-positive breast cancer receiving adjuvant tamoxifen and may contribute to the failure of the tamoxifen treatment by modulating the ER signaling. Our study warrants further investigation into the potential role of SET in ER-positive breast cancer.