Menstrual cycle and surgical treatment of breast cancer: findings from the NCCTG N9431 study

Timing of breast cancer surgery during the menstrual cycle-is there an optimal time of the month?

An intriguing relationship between menstrual cycle phase at the time of breast cancer surgery and clinical outcomes was first proposed in the late 1980s. Despite a number of clinical studies conducted to address this, as well as meta-analyses and systematic reviews, there remains significant controversy surrounding the effect of menstrual cycle phase at time of surgery on the prognosis of premenopausal breast cancer. While some studies have suggested that surgery performed during the luteal phase results in the most favourable outcome, other studies report the follicular phase is more favourable, and others show no association. Given the conflicting results, there remains insufficient evidence to determine whether there is an optimal time of the month to perform surgery. This issue has dogged breast cancer surgery for decades; knowledge of an optimal time of the month to conduct surgery would be a simple approach to improving patient outcomes. This review explores the potential biological mechanisms through which the hormonal milieu might contribute to differences in prognosis, and why clinical findings are so variable. It is concluded that a significant problem with current clinical research is the lack of insight from mechanistic studies. While there are a number of plausible biological mechanisms that could lead to altered survival, supporting evidence is limited. There are also variable approaches to defining the menstrual cycle phase and hormone receptor status of the tumour and few studies controlled for prognostic factors such as tumour size and stage, or addressed the impact of adjuvant treatments. Elucidation of the specific confounding factors, as well as biological mechanistic pathways that could explain the potential relationship between timing of surgery and survival, will greatly assist in designing robust well-controlled prospective clinical studies to evaluate this paradigm.

Luteal versus follicular phase surgical oophorectomy plus tamoxifen in premenopausal women with metastatic hormone receptor-positive breast cancer

PURPOSE

In premenopausal women with metastatic hormone receptor-positive breast cancer, hormonal therapy is the first-line therapy. Gonadotropin-releasing hormone analogue + tamoxifen therapies have been found to be more effective. The pattern of recurrence risk over time after primary surgery suggests that peri-operative factors impact recurrence. Secondary analyses of an adjuvant trial suggested that the luteal phase timing of surgical oophorectomy in the menstrual cycle simultaneous with primary breast surgery favourably influenced long-term outcomes.

METHODS

Two hundred forty-nine premenopausal women with incurable or metastatic hormone receptor-positive breast cancer entered a trial in which they were randomised to historical mid-luteal or mid-follicular phase surgical oophorectomy followed by oral tamoxifen treatment. Kaplan-Meier methods, the log-rank test, and multivariable Cox regression models were used to assess overall and progression-free survival (PFS) in the two randomised groups and by hormone-confirmed menstrual cycle phase.

RESULTS

Overall survival (OS) and PFS were not demonstrated to be different in the two randomised groups. In a secondary analysis, OS appeared worse in luteal phase surgery patients with progesterone levels <2 ng/ml (anovulatory patients; adjusted hazard ratio 1.46, 95% confidence interval [CI]: 0.89-2.41, p = 0.14) compared with those in luteal phase with progesterone level of 2 ng/ml or higher. Median OS was 2 years (95% CI: 1.7-2.3) and OS at 4 years was 26%.

CONCLUSIONS

The history-based timing of surgical oophorectomy in the menstrual cycle did not influence outcomes in this trial of metastatic patients. ClinicalTrials.gov number NCT00293540.

Adjuvant Surgical Oophorectomy Plus Tamoxifen in Premenopausal Women With Operable Hormone Receptor-Positive Breast Cancer: A Global Treatment Option

One third of annual new cases of breast cancer globally are now hormone receptor-positive tumors in premenopausal women from low- and middle-income countries. For this subgroup of women with breast cancer, high-income country guidelines suggest impractical and unaffordable adjuvant treatments. The balance of clinical trial evidence now suggests that surgical oophorectomy plus tamoxifen is a safe and practical treatment for these women in low- and middle-income countries. Additionally, new randomized trial data suggest that women in the second half of an anovulatory cycle benefit minimally from surgical oophorectomy done at this time, which implies that regularly cycling women will benefit more than has been shown from this procedure. Allred scoring of levels of hormone receptors is a practical and inexpensive approach to the assessment of magnitudes of response to oophorectomy plus tamoxifen. These circumstances suggest that more detailed consideration of this option should characterize clinical practice guidelines in high-income countries because of their global impact.

Peri-operative biology in primary breast cancer: a credible therapeutic target

Over the last 25 years, there has been a growing body of basic science, modeling, and clinical data suggesting that the peri-operative period in the treatment of primary breast cancer is dynamic and can be manipulated to improve long-term outcomes. Clinical data have demonstrated early peaks of hazards for recurrence and emphasized the relationship of these to peri-operative events. More recently, clinical trial data with surgical oophorectomy at different times in the menstrual cycle, peri-operative progesterone, and anti-inflammatory drugs suggest that interventional studies are particularly well justified, given the increasing recognition of the costs both financially and clinically of current systemic regimens.

Timing of breast cancer surgery, menstrual phase, and prognosis: Systematic review and meta-analysis

BACKGROUND

For over 25 years, there has been a debate revolving around the timing of breast cancer surgery, menstrual cycle, and prognosis.

METHODS

This systematic review synthesizes and evaluates the body of evidence in an effort to inform evidence-based practice. A keyword and reference search was performed in PubMed and Web of Science to identify human studies that met the inclusion criteria. A total of 58 studies (48 international and 10 U.S.-based) were identified. We provided a narrative summary on study findings and conducted a meta-analysis on a subset of studies where quantitative information was available.

RESULTS

Findings from both qualitative and quantitative analyses were inconclusive regarding performing breast cancer surgery around a specific phase of the menstrual cycle.

CONCLUSION

Based on the Institute of Medicine criteria, evidence is insufficient to recommend a change in current primary breast cancer surgery practice based on menstrual phase.

An interferon signature identified by RNA-sequencing of mammary tissues varies across the estrous cycle and is predictive of metastasis-free survival

The concept that a breast cancer patient's menstrual stage at the time of tumor surgery influences risk of metastases remains controversial. The scarcity of comprehensive molecular studies of menstrual stage-dependent fluctuations in the breast provides little insight. To gain a deeper understanding of the biological changes in mammary tissue and blood during the menstrual cycle and to determine the influence of environmental exposures, such as low-dose ionizing radiation (LDIR), we used the mouse to characterize estrous-cycle variations in mammary gene transcripts by RNA-sequencing, peripheral white blood cell (WBC) counts and plasma cytokine levels. We identified an estrous-variable and hormone-dependent gene cluster enriched for Type-1 interferon genes. Cox regression identified a 117-gene signature of interferon-associated genes, which correlated with lower frequencies of metastasis in breast cancer patients. LDIR (10cGy) exposure had no detectable effect on mammary transcripts. However, peripheral WBC counts varied across the estrous cycle and LDIR exposure reduced lymphocyte counts and cytokine levels in tumor-susceptible mice. Our finding of variations in mammary Type-1 interferon and immune functions across the estrous cycle provides a mechanism by which timing of breast tumor surgery during the menstrual cycle may have clinical relevance to a patient's risk for distant metastases.

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.

Exploiting the critical perioperative period to improve long-term cancer outcomes

Evidence suggests that the perioperative period and the excision of the primary tumour can promote the development of metastases—the main cause of cancer-related mortality. This Review first presents the assertion that the perioperative timeframe is pivotal in determining long-term cancer outcomes, disproportionally to its short duration (days to weeks). We then analyse the various aspects of surgery, and their consequent paracrine and neuroendocrine responses, which could facilitate the metastatic process by directly affecting malignant tissues, and/or through indirect pathways, such as immunological perturbations. We address the influences of surgery-related anxiety and stress, nutritional status, anaesthetics and analgesics, hypothermia, blood transfusion, tissue damage, and levels of sex hormones, and point at some as probable deleterious factors. Through understanding these processes and reviewing empirical evidence, we provide suggestions for potential new perioperative approaches and interventions aimed at attenuating deleterious processes and ultimately improving treatment outcomes. Specifically, we highlight excess perioperative release of catecholamines and prostaglandins as key deleterious mediators of surgery, and we recommend blockade of these responses during the perioperative period, as well as other low-risk, low-cost interventions. The measures described in this Review could transform the perioperative timeframe from a prominent facilitator of metastatic progression, to a window of opportunity for arresting and/or eliminating residual disease, potentially improving long-term survival rates in patients with cancer.

Expression of key oestrogen-regulated genes differs substantially across the menstrual cycle in oestrogen receptor-positive primary breast cancer

Plasma estradiol (E2) and progesterone vary markedly through the menstrual cycle. Data on whether these differences in hormone levels affect gene expression in oestrogen receptor-positive (ER+) tumours are inconsistent. We wished to determine whether there are substantial changes in the expression of oestrogen-regulated genes (ERGs) in ER+ breast cancer through the menstrual cycle. One hundred and seventy five paraffin-embedded ER+ breast carcinomas from premenopausal patients were analysed. Timing of the ovarian cycle was confirmed using serum progesterone levels. Patients were ascribed to one of three pre-defined menstrual cycle windows: 1 (days 27-35 + 1-6), 2 (days 7-16) and 3 (days 17-26). The RNA expression of ESR1, four ERGs (PGR, GREB1, TFF1 and PDZK1), and three proliferation genes (MKI67, TOP2A and CDC20) were compared between the windows. Gene expression of the four ERGs was 53-129 % higher in window 2 than window 1 (p = 0.0013, 0.0006, 0.022 and 0.066 for PGR, GREB1, TFF1 and PDZK1, respectively) and lower (9-41 %) in window 3 compared to window 2 (p = 0.079, 0.31, 0.031 and 0.065 for PGR, GREB1, TFF1 and PDZK1, respectively). Their average expression (AvERG) was 64 % higher in window 2 than window 1 (p < 0.0001) and 21 % lower in window 3 than window 2 (p = 0.0043). There were no significant differences between the windows for ESR1 and proliferation genes. In agreement with the gene expression data, progesterone receptor protein levels measured by immunohistochemistry (IHC) were 164 and 227 % higher in windows 2 and 3, respectively, compared to window 1 (30.7 and 37.9 % cells positive vs. 11.6 %; p = 0.0003 and 0.0004, respectively), while no difference in ER IHC score was observed. In conclusion, we observed significant differences in the expression of ERGs in ER+ breast tumours across the menstrual cycle. This variability may affect the interpretation of gene expression profiles incorporating ERGs and may be exploitable as an endogenous test of endocrine responsiveness.

Promising development from translational or perhaps anti-translational research in breast cancer

Background

A great deal of the public’s money has been spent on cancer research but demonstrable benefits to patients have not been proportionate. We are a group of scientists and physicians who several decades ago were confronted with bimodal relapse patterns among early stage breast cancer patients who were treated by mastectomy. Since the bimodal pattern was not explainable with the then well-accepted continuous growth model, we proposed that metastatic disease was mostly inactive before surgery but was driven into growth somehow by surgery. Most relapses in breast cancer would fall into the surgery-induced growth category thus it was highly important to understand the ramifications of this process and how it may be curtailed. With this hypothesis, we have been able to explain a wide variety of clinical observations including why mammography is less effective for women age 40–49 than it is for women age 50–59, why adjuvant chemotherapy is most effective for premenopausal women with positive lymph nodes, and why there is a racial disparity in outcome.

Methods

We have been diligently looking for new clinical or laboratory information that could provide a connection or correlation between the bimodal relapse pattern and some clinical factor or interventional action and perhaps lead us towards methods to prevent surgery-initiated tumor activity.

Results

A recent development occurred when a retrospective study appeared in an anesthesiology journal that suggested the perioperative NSAID analgesic ketorolac seems to reduce early relapses following mastectomy. Collaborating with these anesthesiologists to understand this effect, we independently re-examined and updated their data and, in search of a mechanism, focused in on the transient systemic inflammation that follows surgery to remove a primary tumor. We have arrived at several possible explanations ranging from mechanical to biological that suggest the relapses avoided in the early years do not show up later.

Conclusions

We present the possibility that a nontoxic and low cost intervention could prevent early relapses. It may be that preventing systemic inflammation post surgery will prevent early relapses. This could be controlled by the surgical anesthesiologist’s choice of analgesic drugs. This development needs to be confirmed in a randomized controlled clinical trial and we have identified triple negative breast cancer as the ideal subset with which to test this. If successful, this would be relatively easy to implement in developing as well as developed countries and would be an important translational result.

Chains of evidence, mosaics of data: does estrogen 'cause' breast cancer? How would we know?

There appears to be a broad consensus that estrogen is a cause of breast cancer. Proof of cause and effect in clinical medicine requires a different approach for an epidemiological exposure (a 'mosaic' approach) than for an infectious agent suspected of causing a particular disease (a 'chain of evidence' approach). This paper discusses the differences between these two approaches in determining the relationship between a risk factor and a disease, and assesses the strength of the data linking estrogen with breast cancer. Analysis of existing data, including findings from the Women's Health Initiative, finds that all nine of the criteria necessary for confirming the epidemiological strength of a risk factor are not met in the case of estrogen, raising serious questions about the validity of this widespread assumption.

Single-injection depot progesterone before surgery and survival in women with operable breast cancer: a randomized controlled trial

PURPOSE

Many nonrandomized studies have suggested better outcome for patients with breast cancer who undergo surgery during the luteal (progestogenic) phase of their menstrual cycle, but this is controversial. We investigated the effect of a single preoperative injection of hydroxyprogesterone in women with operable breast cancer (OBC) in a randomized controlled trial (ClinicalTrials.gov identifier, NCT00123669).

PATIENTS AND METHODS

One thousand patients with OBC were randomly assigned to receive surgery or an intramuscular injection of depot hydroxyprogesterone 500 mg 5 to 14 days before surgery. Primary and secondary end points were disease-free survival (DFS) and overall survival (OS), respectively. An analysis by axillary lymph node status was preplanned.

RESULTS

At a median follow-up of 65 months among 976 eligible patients, 273 recurrences and 202 deaths were recorded. In the progesterone group versus control group, 5-year DFS and OS rates were 73.9% v 70.2% (hazard ratio [HR], 0.87; 95% CI, 0.68 to 1.09; P = .23) and 80.2% v 78.4% (HR, 0.92; 95% CI, 0.69 to 1.21; P = .53), respectively. In 471 node-positive patients, the 5-year DFS and OS rates in the progesterone group versus control group were 65.3% v 54.7% (HR, 0.72; 95% CI, 0.54 to 0.97; P = .02) and 75.7% v 66.8% (HR, 0.70; 95% CI, 0.49 to 0.99; P = .04), respectively. In multivariate analysis, DFS was significantly improved with progesterone in node-positive patients (adjusted HR, 0.71; 95% CI, 0.53 to 0.95; P = .02), whereas there was no significant effect in node-negative patients (P for interaction = .04).

CONCLUSION

A single injection of hydroxyprogesterone before surgery did not improve outcomes in all women with OBC. This intervention showed significant improvement in node-positive women that may be considered hypothesis generating. If replicated in other studies, this could be a simple and inexpensive intervention, especially in developing countries where the incidence of lymph node metastasis is high.

Timing of breast surgery in premenopausal breast cancer patients

BACKGROUND

The majority of women diagnosed with breast cancer undergo a multidisciplinary treatment with surgical intervention and radiotherapy or chemotherapy, or both. The importance of timing of tumour removal in relation to the menstrual cycle and its influence on disease-free survival and overall survival has been studied by researchers since 1989 but still remains speculative.

OBJECTIVES

To determine if surgery performed either during the follicular or luteal phase of the menstrual cycle affects the overall and disease-free survival of premenopausal breast cancer patients.

SEARCH STRATEGY

We searched the Cochrane Breast Cancer Group Trials Register (January 2009), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, Issue 1), MEDLINE (1966 to January 2009), EMBASE (1974 to September 2006) and the WHO International Clinical Trials Registry Platform (ICTRP) search portal (July 2010). We checked references of articles and communicated with authors.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing breast surgery during the follicular phase of the menstrual cycle with the luteal phase in premenopausal women. Prospective non-RCTs or observational studies were considered if randomised studies were lacking.

DATA COLLECTION AND ANALYSIS

Three authors independently extracted data and assessed trial quality.

MAIN RESULTS

Completed randomised trials were not found. There is one trial that is currently ongoing in Italy; the results have yet to be published.Two prospective observational studies had data on recurrence-free survival. One study reported an odds ratio for recurrence rate at one year (where > 1 favours the luteal phase) of 0.86 (95% confidence interval (CI) 0.69 to 1.08); 0.87 at two years (95% CI 0.69 to 1.09); 0.95 at three years (95% CI 0.75 to 1.21); 1.12 at four years (95% CI 0.87 to 1.43); and 1.12 at five years (95% CI 0.87 to 1.43). Another study reported a hazard ratio for overall survival of 1.02 (95% CI 0.995 to 1.04, P = 0.14) and for disease-free survival of 1.00 (95% CI 0.98 to 1.02, P = 0.92) at three years based on the last and first menstrual period. The results were not significant. There was no difference in the recurrence rate whether the surgery was done during the follicular or luteal phase of the menstrual cycle.

AUTHORS' CONCLUSIONS

In the absence of RCTs, this review provides evidence from large prospective observational studies that timing of surgery does not show a significant effect on survival.

Surgery as a double-edged sword: a clinically feasible approach to overcome the metastasis-promoting effects of surgery by blunting stress and prostaglandin responses

Surgery remains an essential therapeutic approach for most solid malignancies, including breast cancer. However, surgery also constitutes a risk factor for promotion of pre-existing micrometastases and the initiation of new metastases through several mechanisms, including the release of prostaglandins and stress hormones (e.g., catecholamines and glucocorticoids). However, the perioperative period also presents an opportunity for cell mediated immunity (CMI) and other mechanisms to eradicate or control minimal residual disease, provided that the deleterious effects of surgery are minimized. Here, we discuss the key role of endogenous stress hormones and prostaglandins in promoting the metastatic process through their direct impact on malignant cells, and through their deleterious impact on anti-cancer CMI. We further discuss the effects of anesthetic techniques, the extent of surgery, pain alleviation, and timing within the menstrual cycle with respect to their impact on tumor recurrence and physiological stress responses. Last, we suggest an attractive perioperative drug regimen, based on a combination of a cyclooxygenase (COX)-2 inhibitor and a β-adrenergic blocker, which we found effective in attenuating immune suppression and the metastasis-promoting effects of surgery in several tumor models. This regimen is clinically applicable, and could potentially promote disease free survival in patients operated for breast and other types of cancer.