Adjuvant chemo-endocrine therapy or endocrine therapy alone for postmenopausal patients: Ludwig Studies III and IV

Personalized adjuvant therapies: lessons from the past: the opening address by the St. Gallen 2013 award recipient

For several decades, personalized adjuvant therapies have been prescribed based on features that predict response to specific types of treatment. In this summary four specific issues regarding adjuvant therapies are described. Each one developed using information from past experience and is ready to be challenged by future findings from clinical trials and maturation of follow-up data. 1) Accuracy of determination of steroid hormone receptors and of HER2-status was the key feature in International Breast Cancer Study Group (IBCSG) and Breast International Group (BIG) trials. 2) Investigations on ovarian function suppression in IBCSG clinical trials led to the design of two trials (SOFT and TEXT), which are likely to lead to improved adjuvant therapy for premenopausal women with breast cancer. 3) Data from the BIG 1-98 trial of letrozole vs tamoxifen for postmenopausal patients with endocrine-responsive breast cancer provided information on which patients might obtain increased benefit from aromatase inhibitors and which might achieve similar treatment outcome with tamoxifen alone. 4) Finally, low-dose, frequently administered cytotoxics (metronomic chemotherapy) were tested in advanced disease with surprisingly favorable disease control and very low incidence of side effects. Personalized treatments are likely to improve substantially with increasingly accurate determination of their targets and by using risk- and toxicity-modulated therapies.

Does treatment at the time of locoregional failure of breast cancer alter prognosis?

Locoregional recurrence (LRR) after therapy for early breast cancer is common. Patients with LRR can suffer local consequences such as bleeding, ulceration, pain and arm oedema or symptoms of metastases. Unlike existing treatment guidelines for primary tumours, both local (surgical and radiation) and systemic treatment recommendations are less well defined after LRR. The purpose of this review was to assess whether or not treatment at the time of locoregional failure ultimately alters a patient's prognosis. Unfortunately, the data from both retrospective and prospective studies are inconclusive and therefore the treatment of patients with LRR will continue to be recommended using guidelines similar to those for primary breast cancer. Future studies of factors predicting LRR and metastatic spread may allow better prognostication of patients with LRR which may in turn effect both local and systemic treatment decisions.

Locoregionally recurrent breast cancer: incidence, risk factors and survival

Locoregional recurrence (LRR) after therapy for early breast cancer is common. Patients with LRR can suffer both local consequences and symptoms of metastatic disease, as LRR is an independent predictor of subsequent distant metastases. Much of the available data on LRR is derived from small, single institution, retrospective studies, so marked differences in the incidence rates for LRR, it's risk factors and subsequent systemic recurrence are reported. The purpose of this review was to try and collate this data in a format that would be useful for both clinicians and their patients.

The Role of Hormonal Therapy in Breast Cancer

This review reassesses the role of hormonal therapy in breast cancer specifically the sequential or concurrent use of endocrine therapy and the combined use of chemotherapy with endocrine therapy. In advanced disease the sequential use of hormone therapies is generally recommended rather than the combined use of various hormonal agents, though combination hormonal therapy offers advantages in certain subsets of patients. The efficacy of combined chemo-endocrine therapy is questionable. Chemotherapy with estrogenic recruitment is an attractive but still experimental concept. However, in an adjuvant setting there is evidence that combined chemo-endocrine therapy causes a significant increase in disease-free and/or overall survival, particularly in postmenopausal patients with estrogen receptor(ER)-positive tumors. While hormonal treatment strategies have clearly benefitted from randomized studies, data regarding optimal endocrine therapy are still insufficient.

Combined chemo-endocrine adjuvant therapy for patients with operable breast cancer: still a question?

Adjuvant systemic treatment delays relapse and prolongs survival in patients with operable breast cancer. However, the relative wealth of available agents and the heterogeneity of the target population contribute to considerable uncertainty about the optimal approach to particular patient groups. Systematic review and meta-analysis of the results of trials testing polychemotherapy have clearly established the value of such treatment. Endocrine treatment with tamoxifen was to be especially useful in patients with hormone-receptor positive tumours. Research in recent years has therefore concentrated on secondary questions, such as scheduling, dose intensity and new combinations of chemotherapeutic agents. Combined chemo-endocrine treatments, using polychemotherapy plus tamoxifen, ovarian ablation or both, have been compared with either modality alone. Other endocrine agents such as fluoxymesterone acetate, medroxyprogesterone acetate and, recently, LH-RH analogues have also received attention. The systematic review presented here suggests that combined cytotoxic and endocrine therapies might be the most effective use of available treatments for most, if not all, patients, and highlights the unresolved questions requiring further research.

Postoperative adjuvant randomised trial comparing chemoendocrine therapy, chemotherapy and immunotherapy for patients with stage II breast cancer: 5-year results from the Nishinihon Cooperative Study Group of Adjuvant Chemoendocrine Therapy for Breast Cancer (ACETBC) of Japan

Between 1985 and 1988, the effect of using ftorafur (FT) or PSK (an immunotherapy agent) in combination with the conventional postoperative adjuvant therapy using mitomycin (MMC) plus tamoxifen (TAM) was assessed in stage II, oestrogen receptor-positive (ER+) breast cancer patients. Furthermore, in ER- breast cancer stage II patients, the effects of postoperative adjuvant therapy using MMC plus FT were compared with the effects of postoperative adjuvant therapy using MMC plus PSK. Patients had primary stage II breast cancer and had undergone total mastectomy plus axillary dissection or more radical surgery. On the day of surgery, MMC (13 mg/m2) was administered intravenously. Then, ER+ patients received one of three regimens of drug therapy, starting 2 weeks after surgery: regimen A (daily oral treatment with 30 mg of TAM), regimen B (daily oral treatment with 30 mg of TAM and 600 mg of FT) or regimen C (daily oral treatment with 30 mg of TAM and 3 g of PSK) [corrected]. ER- patients received either regimen D (daily oral treatment with 600 mg of FT) or regimen E (daily oral treatment with 3 g of PSK), starting 2 weeks after surgery. Of the 540 ER+ patients registered, 525 were evaluated. The 5-year overall survival rate for ER+ patients was higher for patients who received regimen B (94.2%) than for those who received regimen A (86.9%) or regimen C (89.9%) (P = 0.063). The 5-year relapse-free survival rate was higher for regimen B (88.9%) than for regimen A (78.6%) and regimen C (77.2%) (P = 0.010). Stratified analysis revealed better results with the FT-combined therapy in patients positive for lymph node metastasis and premenopausal patients. These results indicate the effectiveness of using FT in combination with TAM. Of the 376 ER- patients registered, 364 were evaluated. The 5-year overall and relapse-free survival rate for ER- patients did not differ significantly between patients who received regimen D and those who received regimen E.

Patterns of tumor relapse following mastectomy and adjuvant systemic therapy in patients with axillary lymph node-positive breast cancer. Impact of clinical, histopathologic, and flow cytometric factors

BACKGROUND

This analysis was conducted to evaluate the impact of selected clinical, histopathologic, and flow cytometric factors on sites of initial tumor relapse after postmastectomy adjuvant systemic therapy.

METHODS

Five hundred sixty-four patients with axillary node-positive breast cancer were entered in two prospectively randomized trials and received cyclophosphamide, 5-fluorouracil and prednisone with or without tamoxifen as sole adjuvant therapy. These patients were studied to assess the risk of locoregional recurrence and to identify factors that might predict tumor relapse site.

RESULTS

With a median follow-up of 9.3 years, the 8-year cumulative incidences of initial locoregional or distant relapse were 20% and 35%, respectively. Pathologic tumor stage, estrogen receptor content, and number of involved axillary nodes were independent predictive factors for an increased risk of locoregional recurrence. With the exception of tumor stage, these factors also were associated with an increased risk of distant relapse so that tumor stage (T3a) remained the sole factor predictive of increased relative risk for initial locoregional (versus distant) recurrence in patients with tumor progression. Clinical and flow cytometric factors were not predictive of initial locoregional or distant relapse.

CONCLUSIONS

Exploratory data analysis of two prospective trials of postmastectomy adjuvant systemic therapy has demonstrated a significant risk for initial isolated locoregional recurrence in certain patients with node-positive breast cancer. The benefit of improved locoregional tumor control in appropriately selected patients with axillary node-positive breast cancer who receive adjuvant systemic therapy requires additional investigation.

Adjuvant systemic therapy in breast cancer

Systemic adjuvant therapy has improved the prognosis of patients with primary breast cancer. Meta-analyses have demonstrated that approximately one fourth of deaths can be avoided among younger women treated with multiple cytotoxic drug regimens and among older women treated with tamoxifen. However, with the treatments available today many aspects related to the optimal therapy, taking into account the physical, psychological and socioeconomic consequences, are still open. This review discusses some of the major open questions related to the effectiveness of the adjuvant systemic therapy in terms of its ability to reduce recurrence rate and mortality.