Survival after adjuvant oophorectomy and tamoxifen in operable breast cancer in premenopausal women

Fertility preservation in patients undergoing gonadotoxic treatments: a Canadian Fertility and Andrology Society clinical practice guideline

The management of young patients with cancer presents several unique challenges. In general, these patients are ill prepared for the diagnosis and the impact on their fertility. With the improved survival for all tumour types and stages, the need for adequate fertility counselling and a multidisciplinary approach in the reproductive care of these patients is paramount. Recent advances in cryopreservation techniques allow for the banking of spermatozoa, oocytes, embryos and ovarian tissue without compromising survival. This Canadian Fertility and Andrology Society (CFAS) guideline outlines the current understanding of social and medical issues associated with oncofertility, and the medical and surgical technologies available to optimize future fertility.

Oophorectomy in Premenopausal Patients with Estrogen Receptor-Positive Breast Cancer: New Insights into Long-Term Effects

Approximately 80% of breast cancers are estrogen receptor-positive (ER+), and 68-80% of those occur in premenopausal or perimenopausal women. Since the introduction of tamoxifen for adjuvant endocrine therapy in women with non-metastatic ER+ breast cancer, subsequent trials have demonstrated an oncologic benefit with the addition of ovarian function suppression (OFS) to adjuvant endocrine therapy. Subsequently, therapies to either suppress or ablate ovarian function may be included in the treatment plan for patients that remain premenopausal or perimenopausal after upfront or adjuvant chemotherapy and primary surgery. One strategy for OFS, bilateral salpingo-oophorectomy (BSO), has lasting implications, and the routine recommendation for this strategy warrants a critical analysis in this population. The following is a narrative review of the utility of ovarian suppression or ablation (through either bilateral oophorectomy or radiation) in the context of adjuvant endocrine therapy, including selective estrogen receptor modulators (SERMs) and aromatase inhibitors (AIs). The long-term sequelae of bilateral oophorectomy include cardiovascular and bone density morbidity along with sexual dysfunction, negatively impacting overall quality of life. As gynecologists are the providers consulted to perform bilateral oophorectomies in this population, careful consideration of each patient's oncologic prognosis, cardiovascular risk, and psychosocial factors should be included in the preoperative assessment to assist in shared decision-making and prevent the lifelong adverse effects that may result from overtreatment.

Breast Cancer Survival Defined by Biological Receptor and Menopausal Status in Vietnamese Women

Little is known about breast cancer in Vietnamese women. Previous studies have reported the frequencies of prognostic factors of breast cancer in this population. The aim of this study was to examine the prognostic factors associated with the survival rates of patients with breast cancer treated at the National Cancer Hospital, Hanoi, Vietnam. We recruited 248 women with operable breast cancer treated with surgery and adjuvant therapy. Tumor tissue samples were stained by many immunohistochemical approaches and analyzed for estrogen receptor, progesterone receptor, and HER2 gene amplification status. A Cox model was used to determine the relationship between survival and the prognostic factors. The disease-free survival rate, overall survival rate, and cancer-specific survival rate were 75.8%, 80.6%, and 86.4%, respectively, at 5 years and 62.3%, 68.1%, and 78.9%, respectively, at 10 years. The lung was the most common metastatic site. Women with factors associated with a poor prognosis (eg, advanced clinical stage, high tumor grade, progesterone receptor [PR] negativity, HER2 amplification) had significantly lower survival rates. Patients with PR-negative breast cancer had significantly worse survival rates compared to those who were PR positive, according to multivariate analysis (hazard ratio = 1.77, 95% confidence interval: 1.01-3.11, P = .045); however, there was only a statistically significant difference in postmenopausal patients. The PR was a prognostic factor in postmenopausal women with breast cancer, but not in premenopausal women.

Follow up after sample size re-estimation in a breast cancer randomized trial for disease-free survival

BACKGROUND

While the clinical trials and statistical methodology literature on sample size re-estimation (SSRE) is robust, evaluation of SSRE procedures following the completion of a clinical trial has been sparsely reported. In blinded sample size re-estimation, only nuisance parameters are re-estimated, and the blinding of the current trial treatment effect is preserved. Blinded re-estimation procedures are well-accepted by regulatory agencies and funders. We review our experience of sample size re-estimation in a large international, National Institutes of Health funded clinical trial for adjuvant breast cancer treatment, and evaluate our blinded sample size re-estimation procedure for this time-to-event trial. We evaluated the SSRE procedure by examining assumptions made during the re-estimation process, estimates resulting from re-estimation, and the impact on final trial results with and without the addition of participants, following sample size re-estimation.

METHODS

We compared the control group failure probabilities estimated at the time of SSRE to estimates used in the original planning, to the final un-blinded control group failure probability estimates for those included in the SSRE procedure (SSRE cohort), and to the final total control group failure probability estimates. The impact of re-estimation on the final comparison between randomized treatment groups is evaluated for those in the originally planned cohort (n = 340) and for the combination of those recruited in the originally planned cohort and those added after re-estimation (n = 509).

RESULTS

Very little difference is observed between the originally planned cohort and all randomized patients in the control group failure probabilities over time or in the overall hazard ratio estimating treatment effect (originally planned cohort HR 1.25 (0.86, 1.79); all randomized cohort HR 1.24 95% CI (0.91, 1.68)). At the time of blinded SSRE, the estimated control group failure probabilities at 3 years (0.24) and 5 years (0.40) were similar to those for the SSRE cohort once un-blinded (3 years, 0.22 (0.16, 0.30); 5 years, 0.33 (0.26, 0.41)).

CONCLUSIONS

We found that our re-estimation procedure performed reasonably well in estimating the control group failure probabilities at the time of re-estimation. Particularly for time-to-event outcomes, pre-planned blinded SSRE procedures may be the best option to aid in maintaining power.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT00201851 . Registered on 9 September 2005. Retrospectively registered.

Molecular changes in premenopausal oestrogen receptor-positive primary breast cancer in Vietnamese women after oophorectomy

For premenopausal women with primary ER + breast cancer, oophorectomy (OvX) is an evidence-based cost-effective option and is standard treatment in many countries. However, there is virtually no data describing the effects of OvX on breast tumour biology. We therefore, characterised the endocrine and genome-wide transcriptional impact of OvX in 56 premenopausal women with ER + breast cancer for 2 weeks prior to mastectomy. Plasma estradiol concentrations decreased from 406 ± 41 to 20.7 ± 2.6 pmol/l (mean ± sem) 24 h after OvX, and to 8.1 ± 0.8 pmol/l 2 weeks later at mastectomy. Ki67 decreased in 33/36 (91.7%) tumours. The expression of 655 genes changed significantly (FDR < 1%) with an absolute mean fold-change (FC) ≥ 1.25 (257 up, 398 down). Archetypal oestrogen-regulated genes (TFF1, GREB1, PGR and PDZK1) showed large decreases in expression (FC = 0.20–0.69; p < 1e-6-1e-7). Proliferation-associated genes (e.g. TOP2A, AURKA and UBE2C) were also strongly downregulated (FC = 0.38–0.56; p < 1e-7) along with putative progesterone-regulated genes (e.g. FKBP4, MYB; FC = 0.64–0.68; p < 1e-4-1e-7). The gene expression changes did not differ according to HER2 status and correlated strongly with the changes reported previously after aromatase inhibitor (AI) treatment in postmenopausal women (rho = 0.55, p < 1e-04). However, after OvX the mean FC was significantly higher compared to AI (p < 1e-04). In conclusion, changes in tumoural gene expression after OvX were largely similar, but of a greater magnitude to those observed after AI in postmenopausal patients; however, OvX appeared to have a greater effect on progesterone-regulated genes than AI.

Surgical removal of the ovaries alters the expression of hundreds of genes in the tumour cells of premenopausal women with breast cancer. Ben Haynes from Royal Marsden Hospital in London, UK and colleagues characterised molecular changes in 56 premenopausal women from Vietnam with oestrogen receptor-positive breast cancer who underwent oophorectomies, a standard treatment for this patient population. They showed that blood levels of the hormone estradiol dropped precipitously following ovary-removal surgery. Levels of a protein that was indicative of tumour growth also went down, as did genes involved in regulating hormone signalling and cell proliferation. The results are consistent with those seen in postmenopausal women following treatment with an oestrogen-blocking drug, but oophorectomy had a more dramatic effect. The data could aid the search for predictive biomarkers of who stands to benefit most from ovary removal.

Is Estradiol Monitoring Necessary in Women Receiving Ovarian Suppression for Breast Cancer?

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors’ suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

A 36-year-old premenopausal woman had been diagnosed with stage III breast cancer. After an initial biopsy confirmed breast cancer, she underwent mastectomy and axillary node dissection for a left-sided breast cancer, measuring 7 cm. The tumor had lobular histology and was considered grade 2 of 3. Metastatic carcinoma was identified in 10 of 13 axillary nodes. Immunohistochemical studies showed that the tumor was strongly positive for estrogen and progesterone receptor expression and had a Ki-67 score of 15% (> 20% is considered high according to a Swedish quality control study and the St Gallen Expert Consensus). 1 , 2 There was no amplification of the HER2/neu gene. Staging scans were negative for metastatic disease. In the adjuvant setting, she received three cycles of anthracycline-cyclophosphamide combination chemotherapy followed by three cycles of taxane chemotherapy and then locoregional radiotherapy. After completion of chemotherapy, she developed amenorrhea. As adjuvant endocrine therapy, she began monthly goserelin administration to achieve ovarian function suppression (OFS), in combination with the aromatase inhibitor (AI) exemestane. She experienced menopausal symptoms including hot flashes, vaginal dryness, and sexual dysfunction. After two monthly treatments with goserelin and exemestane, a sensitive assay for serum estradiol was checked and returned at 16 pg/mL (61 pmol/L); postmenopausal range for sensitive assay is less than 15 pg/mL (< 50 pmol/L). The patient has now been referred to our unit to discuss further management.

Fertility preservation in reproductive-age women facing gonadotoxic treatments

BACKGROUND

Advancements in the treatments for cancer and autoimmune and other hematologic conditions continue to improve survival and cure rates. Despite those changes, various gonadotoxic agents and other treatments can still compromise the future fertility of many women. Progress in medical and surgical reproductive technologies has helped to offset the reproductive consequences of the use of gonadotoxic therapies, and allows for future fertility and normal pregnancy.

METHODS

A review of the literature was performed to outline the pathophysiology of gonadotoxicity from various treatments. The success of fertility preservation, fertility sparing, and cryopreservation options are reviewed. Barriers and facilitators to referral and oncofertility treatment in Canada are also outlined.

RESULTS

According to the quality of the evidence, recommendations are made for fertility assessment, patient referral, cryopreservation, and other assisted reproductive technologies.

CONCLUSIONS

To ensure ongoing fertility in women undergoing gonadotoxic treatments, assisted reproductive technologies can be combined with a multidisciplinary approach to patient assessment and referral.

Timing of adjuvant surgical oophorectomy in the menstrual cycle and disease-free and overall survival in premenopausal women with operable breast cancer

BACKGROUND

For women with hormone receptor-positive, operable breast cancer, surgical oophorectomy plus tamoxifen is an effective adjuvant therapy. We conducted a phase III randomized clinical trial to test the hypothesis that oophorectomy surgery performed during the luteal phase of the menstrual cycle was associated with better outcomes.

METHODS

Seven hundred forty premenopausal women entered a clinical trial in which those women estimated not to be in the luteal phase of their menstrual cycle for the next one to six days (n = 509) were randomly assigned to receive treatment with surgical oophorectomy either delayed to be during a five-day window in the history-estimated midluteal phase of the menstrual cycles, or in the next one to six days. Women who were estimated to be in the luteal phase of the menstrual cycle for the next one to six days (n = 231) were excluded from random assignment and received immediate surgical treatments. All patients began tamoxifen within 6 days of surgery and continued this for 5 years. Kaplan-Meier methods, the log-rank test, and multivariable Cox regression models were used to assess differences in five-year disease-free survival (DFS) between the groups. All statistical tests were two-sided.

RESULTS

The randomized midluteal phase surgery group had a five-year DFS of 64%, compared with 71% for the immediate surgery random assignment group (hazard ratio [HR] = 1.24, 95% confidence interval [CI] = 0.91 to 1.68, P = .18). Multivariable Cox regression models, which included important prognostic variables, gave similar results (aHR = 1.28, 95% CI = 0.94 to 1.76, P = .12). For overall survival, the univariate hazard ratio was 1.33 (95% CI = 0.94 to 1.89, P = .11) and the multivariable aHR was 1.43 (95% CI = 1.00 to 2.06, P = .05). Better DFS for follicular phase surgery, which was unanticipated, proved consistent across multiple exploratory analyses.

CONCLUSIONS

The hypothesized benefit of adjuvant luteal phase oophorectomy was not shown in this large trial.

[Muscle invasive bladder cancer after radical cystectomy. Prognostic factors of adjuvant chemotherapy]

BACKGROUND

The indications to administer adjuvant systemic chemotherapy to patients with urothelial carcinoma of the bladder who underwent radical cystectomy is discussed controversially and all international guidelines are very restrictive with regard to its recommendation for routine daily practice due to the low scientific evidence concerning its therapeutic benefit. Currently, adjuvant systemic chemotherapy should be preferably administered within clinical trials. In the daily routine adjuvant treatment might be given in patients with lymph node positive disease. Clinical, pathohistological and molecular biomarkers which might be associated with a positive or negative treatment response have been evaluated sparsely in the past.

RESULTS

The presence of hemangiosis/lymphangiosis carcinomatosa and/or extranodal expansion in patients with lymph node metastases appears to be associated with a poor outcome. The markers ERCC-1, XAF and anti-apoptotic proteins of the Bcl-2 family seem to represent the most promising biomarkers associated with response to adjuvant cisplatin-based chemotherapy.

Using decision aids to improve treatment choices for women with breast cancer

SUMMARY Breast cancer is the most frequently diagnosed cancer in women worldwide and decision-making regarding treatment options can be complex; however, patients often desire to be involved in health-related decisions. There has been a growing body of research into decision-support tools such as decision aids (DAs). Generally, DAs outperform standard care over a range of decision-making outcomes and there are some that have been developed for use with breast cancer patients across the treatment trajectory, which have been evaluated for use in practice. There is scope for developing additional DAs for cancer patients, however, there are some limitations and barriers that need to be overcome as part of the implementation process. Consideration for the mechanisms for maintaining relevancy of materials and ease of accessibility is also needed.

Comparison of absolute benefits of anticancer therapies determined by snapshot and area methods

BACKGROUND

Reporting of relative risk reduction as the measure of treatment effect in randomized clinical trials (RCTs) may be difficult to understand. Here, we compare two methods for assessing absolute benefits of anticancer therapies.

MATERIALS AND METHODS

We searched PubMed for RCTs comparing therapies for breast and colorectal cancers published 1975-2009 (adjuvant setting) and 2000-2010 (metastatic setting). Eligible trials reported statistically significant differences. Kaplan-Meier curves were assessed for absolute differences in time-to-event end points at a single point (snapshot method) and as the area between curves (area method). Pooled absolute benefits determined by both methods were compared by the Pitman-Morgan test.

RESULTS

Eighty-three and 39 paired curves were assessed in the adjuvant and metastatic settings, respectively. In trials of adjuvant therapy, absolute benefits were larger and more variable when assessed at different time points by the snapshot compared with the area method (median and ranges for 60-month difference in overall survival: 7.6% [2.5%-28.4%] and 4.5% [1.8%-13.6%]; P = 0.002, respectively). For metastatic disease, both methods were within 0.5 month of each other in 62% of trials.

CONCLUSIONS

The area method provides an alternative measure of absolute treatment effect, which uses all of the available data and is less dependent on the shape of survival curves.

Effects on survival of menstrual cycle phase of adjuvant surgical oophorectomy in premenopausal women with breast cancer

Adjuvant surgical oophorectomy is an effective and remarkably cost effective treatment for premenopausal women with hormone receptor positive operable breast cancer. Previously published secondary analyses indicated a survival benefit for patients whose surgery was performed in the luteal phase of the menstrual cycle as opposed to the follicular. This study utilizes additional follow-up and more fully examines this hypothesis and the general implications of long-term follow-up on trial design. Beginning in 1993 we recruited women to a multicenter randomized clinical trial of adjuvant surgical oophorectomy and tamoxifen for 5 years. We recorded the reported day 1 of the patients' last menstrual cycle on the day of their adjuvant surgery. We conducted secondary analyses of the association of history-estimated luteal or follicular phase oophorectomy surgery with disease-free and overall survival. In multivariable Cox analyses, disease-free survival (DFS) exhibited a positive trend and overall survival (OS) showed a significant improvement in patients whose surgery was estimated to have occurred in the luteal phase of the menstrual cycle compared to the follicular (HR for DFS: 0.66, 95% CI: 0.37-1.16; HR for OS: 0.49, 95% CI: 0.27-0.88). From the hazard function plots, it appears that the luteal phase surgery effect on DFS diminishes after 6 years of follow-up. In conclusion, adjuvant surgical oophorectomy during the luteal phase of the menstrual cycle resulted in a reduced hazard of recurrence as compared to oophorectomy in the follicular phase during the first 5.5 years of follow-up. The practical and biological implications of these findings deserve rigorous evaluation in clinical trials.

Benefits and adverse effects of endocrine therapy

Endocrine-responsive tumors that are small and without nodal involvement (i.e. tumors classified as pT1 pN0) are a heterogeneous group of tumors that are associated with a low risk of relapse in the majority of the cases. Therefore, the costs and benefits of adjuvant endocrine therapy should be carefully considered within this subgroup of patients. Treatment decisions should take into consideration co-morbidities as well as the presence of other classical risk factors such as HER2 overexpression or extensive peritumoral vascular invasion. Tamoxifen or tamoxifen plus ovarian function suppression should be considered as proper endocrine therapies in premenopausal patients. Ovarian function suppression alone or ovarian ablation might also be considered adequate in selected patients (e.g. very low-risk patients, in the presence of co-morbidities or patient preference). An aromatase inhibitor should form part of standard endocrine therapy for most postmenopausal women with receptor-positive breast cancer, although patients at low risk or with co-morbid musculoskeletal or cardiovascular risk factors may be considered suitable for tamoxifen alone. Tailored endocrine treatments should be considered in patients with endocrine-responsive tumors classified as pT1 pN0. Issues focusing on safety, quality of life and subjective side effects should be routinely discussed.

Adjuvant hormonal therapy for early-stage breast cancer

Adjuvant endocrine treatment is an essential component in therapy for hormone receptor-positive breast cancer. Among postmenopausal patients, options include tamoxifen, aromatase inhibitors, or a sequence of these agents. Tamoxifen and aromatase inhibitors have distinctive side-effect profiles. Among premenopausal women, tamoxifen remains the standard treatment. The role of ovarian suppression in addition to tamoxifen is under investigation. Questions about the duration of adjuvant endocrine therapy, the use of biomarkers for treatment selection and prognosis, and the management of side effects of adjuvant endocrine therapy remain key areas of investigation.

Adjuvant endocrine therapy for premenopausal women with breast cancer

AIMS

Endocrine therapy is a pivotal treatment for women with hormone-receptor positive breast cancer. In premenopausal women, endocrine therapy primarily consists of tamoxifen and ovarian suppressive strategies. Younger women experience improvements in the risks of relapse or death from breast cancer with the use of chemotherapy as well, with part of this benefit explained by resultant premature amenorrhea. Unfortunately despite a centuries worth of clinical trials, the most efficacious combination of hormonal therapies and chemotherapy has yet to be determined. This paper serves as a comprehensive review of the substantial data in the adjuvant treatment of premenopausal, hormone receptor-positive women with breast cancer.

METHODS AND RESULTS

PubMed and American Society of Clinical Oncology (ASCO) Proceedings searches from 1896 to present were performed. All of the trials examining the role of ovarian suppression and tamoxifen with and without chemotherapy in premenopausal women were included. The current data suggests that endocrine therapy can be an important alternative to chemotherapy in select patient populations, and improvements in outcome are also seen with the combination of hormonal and chemotherapy strategies in other populations. A majority of the trials examined did not use what is considered to be current standards of care regarding chemotherapy regimens and durations of adjuvant hormonal therapy. Many unanswered questions remain particularly regarding the combined use of ovarian suppression and tamoxifen in women who are also receiving chemotherapy.

CONCLUSION

There is a persistent need to define optimal endocrine therapy in premenopasusal women with hormone-receptor positive breast cancer. Contemporaneous trials, such as the SOFT trial will provide direction, and additional biomarker and pharmacogenomic data will further supplement individualized patient decision making.

Sample size re-estimation in a breast cancer trial

BACKGROUND

During the recruitment phase of a randomized breast cancer trial, investigating the time to recurrence, we found a strong suggestion that the failure probabilities used at the design stage were too high. Since most of the methodological research involving sample size re-estimation has focused on normal or binary outcomes, we developed a method which preserves blinding to re-estimate sample size in our time to event trial.

PURPOSE

A mistakenly high estimate of the failure rate at the design stage may reduce the power unacceptably for a clinically important hazard ratio. We describe an ongoing trial and an application of a sample size re-estimation method that combines current trial data with prior trial data or assumes a parametric model to re-estimate failure probabilities in a blinded fashion.

METHODS

Using our current blinded trial data and additional information from prior studies, we re-estimate the failure probabilities to be used in sample size re-calculation. We employ bootstrap re-sampling to quantify uncertainty in the re-estimated sample sizes.

RESULTS

At the time of re-estimation data from 278 patients were available, averaging 1.2 years of follow up. Using either method, we estimated a sample size increase of zero for the hazard ratio because the estimated failure probabilities at the time of re-estimation differed little from what was expected. We show that our method of blinded sample size re-estimation preserves the type I error rate. We show that when the initial guess of the failure probabilities are correct, the median increase in sample size is zero.

LIMITATIONS

Either some prior knowledge of an appropriate survival distribution shape or prior data is needed for re-estimation.

CONCLUSIONS

In trials when the accrual period is lengthy, blinded sample size re-estimation near the end of the planned accrual period should be considered. In our examples, when assumptions about failure probabilities and HRs are correct the methods usually do not increase sample size or otherwise increase it by very little. Clinical Trials 2010; 7: 219. http://ctj.sagepub.com.

Breast cancer in young women and its impact on reproductive function

BACKGROUND

Breast cancer is the most common cancer in women in developed countries, and 12% of breast cancer occurs in women 20-34 years. Survival from breast cancer has significantly improved, and the potential late effects of treatment and the impact on quality of life have become increasingly important. Young women constitute a minority of breast cancer patients, but commonly have distinct concerns and issues compared with older women, including queries regarding fertility, contraception and pregnancy. Further, they are more likely than older women to have questions regarding potential side effects of therapy and risk of relapse or a new primary. In addition, many will have symptoms associated with treatment and they present a management challenge. Reproductive medicine specialists and gynaecologists commonly see these women either shortly after initial diagnosis or following adjuvant therapy and should be aware of current management of breast cancer, the options for women at increased genetic risk, the prognosis of patients with early stage breast cancer and how adjuvant systemic treatments may impact reproductive function.

METHODS

No systematic literature search was done. The review focuses on the current management of breast cancer in young women and the impact of treatment on reproductive function and subsequent management. With reference to key studies and meta-analyses, we highlight controversies and current unanswered questions regarding patient management.

RESULTS

Chemotherapy for breast cancer is likely to negatively impact on reproductive function. A number of interventions are available which may increase the likelihood of future successful pregnancy, but the relative safety of these interventions is not well established. For those who do conceive following breast cancer, there is no good evidence that pregnancy is detrimental to survival. We review current treatment; effects on reproductive function; preservation of fertility; contraception; pregnancy; breastfeeding and management of menopausal symptoms following breast cancer.

CONCLUSION

This paper provides an update on the management of breast cancer in young women and is targeted at reproductive medicine specialists and gynaecologists.

Role of biologic therapy and chemotherapy in hormone receptor- and HER2-positive breast cancer

BACKGROUND

To review the efficacy of chemotherapy and human epidermal growth factor receptor 2 (HER2)-targeted therapy when used in addition to hormonal therapy for the optimal management of estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-positive (HER2+) breast cancer.

DESIGN

Literature published from January 2003 to March 2008 was reviewed to assess the use of chemotherapy and biologic therapy in addition to hormonal agents.

RESULTS

Aromatase inhibitors (AIs) demonstrated greater effectiveness in the adjuvant setting than tamoxifen for the management of ER+ and HER2+ breast cancer. Evidence of cross talk between HER2- and ER-signaling pathways suggests that combined treatment with HER2 blockade and hormonal therapy may offer clinical advantages beyond those provided by hormonal therapy alone in ER+/HER2+ disease. Combined therapy with trastuzumab plus an aromatase AI significantly improves progression-free survival, response rates, and clinical benefits when compared with AI monotherapy in postmenopausal women. Several large studies demonstrated that trastuzumab significantly improves disease-free and overall survival when given in combination with, or following, chemotherapy, regardless of hormone receptor status.

CONCLUSIONS

HER2-targeted therapy maybe combined with AIs for the treatment of ER+/HER2+ metastatic breast cancer in postmenopausal women. HER2-targeted therapy in combination with AIs for treatment of ER+/HER2+ early breast cancer needs to be prospectively evaluated.

Surgical oophorectomy for breast cancer: back to the future

While the preponderance of current scientific presentations on breast cancer therapies has focused on chemotherapeutic strategies, targeted therapy with tyrosine kinase inhibitors and hormonal therapies for postmenopausal women, the majority of worldwide cases of breast cancer occur in premenopausal women, for whom practical inexpensive hormonal therapy, surgical oophorectomy, is the most common attainable treatment. In hormone-receptor-positive breast cancer, meta-analysis data from older trials, and more specific recent trial data have made clearer the chronic natural history of this broad subtype of disease and the central role of hormonal therapy in its control. Greater understanding of the critical variables in pathology procedures for breast tumor tissue hormonal receptor testing is leading to better definitions of the specific patients for whom hormonal therapies are indicated. Closer examination of outcomes following surgical oophorectomy has suggested that more than just downregulation of estrogen stimulated breast cancer growth; the reduction of systemic estrogen levels also occurs with this procedure. When combined with antiestrogen treatment using tamoxifen in patients who are active metabolizers of this drug, surgical oophorectomy is a remarkably effective and cost-effective treatment. This combination of circumstances suggests that this first hormonal therapy for breast cancer may once again, have a much greater role globally.

Defining a global research agenda for breast cancer

In contrast to western high-income nations, the incidence and mortality from breast cancer are increasing in most low and middle-income countries worldwide. Current approaches to breast cancer control developed for populations of high-income societies should not be directly transferred without evaluation. A relevant research agenda includes population differences in tumor biology and metabolization of systemic therapies, cultural and psychosocial issues, and operations in healthcare systems. Highest priority should be given to assessments of clinical downstaging and basic systemic treatment effectiveness in low and middle-income populations. Partnerships of existing organizations in high-income nations with those in low and middle-income countries are currently the most feasible sources of research support.