A randomized clinical trial of adjuvant chemotherapy for radically resected locoregional relapse of breast cancer: IBCSG 27-02, BIG 1-02, and NSABP B-37

Long-Term Survival Outcomes and Risk Factors for Axillary and Locoregional Recurrence in Japanese Patients with Sentinel Node-Positive Breast Cancer Treated in Accordance with the ACOSOG Z0011 Strategy

INTRODUCTION

In 2018, we reported the results of a study to assess the feasibility of applying the ACOSOG Z0011 criteria to Japanese patients with early-stage breast cancer (median follow-up, 3 years). Their results over the longer term can now be presented. Risk factors for axillary and locoregional recurrence in Z0011-eligible patients are unknown.

METHODS

Long-term survival outcomes were investigated by analyzing data from patients enrolled in the feasibility study. Data from the feasibility study patients, and from patients eligible for the Z0011 strategy after its introduction into clinical practice, were subjected to multivariate logistic regression analysis to identify risk factors for axillary and locoregional recurrence.

RESULTS

Regarding long-term outcomes for the feasibility study patients (n = 189), distant disease-free survival rates at 5 and 7 years were 90.4 ± 2.1% and 85.9 ± 2.6%, respectively, and overall survival rates at 5 and 7 years were 97.3 ± 1.2% and 95.3 ± 1.7%, respectively. Analysis of data from these patients plus the 93 who received Z0011 in clinical practice (total, n = 282) identified the following independent risk factors for axillary recurrence: absence of high axillary tangential irradiation (OR, 5.87 [95% CI, 1.09-31.35], p = 0.04) and number of positive sentinel lymph nodes (OR, 4.65 [95% CI, 1.11-19.48], p = 0.04). Only high Ki67 labeling index (OR, 5.92 [95% CI, 1.31-26.70], p = 0.02) was identified as an independent risk factor for locoregional recurrence.

CONCLUSION

Long-term survival outcome results of the feasibility study show that the Z0011 strategy can be used to treat Japanese patients with early-stage breast cancer. Our findings regarding risk factors suggest that high axillary tangent irradiation is necessary for the prevention of axillary recurrence and that irradiation, including of the regional lymph nodes, should be considered, especially in patients with high Ki67 index values.

Does post mastectomy radiotherapy reduce loco-regional recurrence rates in all clinical stages of breast cancer following a complete pathological response to neoadjuvant chemotherapy? A systematic review and meta-analysis of the literature

The role of post-mastectomy radiotherapy (PMRT) has not been qualified in contemporary cohorts that have achieved complete pathological response (pCR) following neoadjuvant chemotherapy (NAC). This systematic review evaluated loco-regional recurrence (LRR) rates following PMRT for patients with pCR or pathologically lymph node negative disease (ypN0) after NAC. We identified seven papers that described LRR in 415 patients with pCR following NAC. Pooled analysis demonstrated clear benefit of PMRT on LRR (OR: 0.2 [95% CI: 0.06–0.58; p = 0.003]) and this was most pronounced in stage III/IV disease (OR: 0.12 [95% CI: 0.04–0.44; p = 0.0012]), as well as of benefit in ypN0 disease. PMRT appears to be effective in reducing LRR following pCR or ypN0 in advanced breast cancer but requires further investigation.

Dynamics of breast-cancer relapse reveal late-recurring ER-positive genomic subgroups

The rates and routes of lethal systemic spread in breast cancer are poorly understood owing to a lack of molecularly characterized patient cohorts with long-term, detailed follow-up data. Long-term follow-up is especially important for those with oestrogen-receptor (ER)-positive breast cancers, which can recur up to two decades after initial diagnosis1-6. It is therefore essential to identify patients who have a high risk of late relapse7-9. Here we present a statistical framework that models distinct disease stages (locoregional recurrence, distant recurrence, breast-cancer-related death and death from other causes) and competing risks of mortality from breast cancer, while yielding individual risk-of-recurrence predictions. We apply this model to 3,240 patients with breast cancer, including 1,980 for whom molecular data are available, and delineate spatiotemporal patterns of relapse across different categories of molecular information (namely immunohistochemical subtypes; PAM50 subtypes, which are based on gene-expression patterns10,11; and integrative or IntClust subtypes, which are based on patterns of genomic copy-number alterations and gene expression12,13). We identify four late-recurring integrative subtypes, comprising about one quarter (26%) of tumours that are both positive for ER and negative for human epidermal growth factor receptor 2, each with characteristic tumour-driving alterations in genomic copy number and a high risk of recurrence (mean 47-62%) up to 20 years after diagnosis. We also define a subgroup of triple-negative breast cancers in which cancer rarely recurs after five years, and a separate subgroup in which patients remain at risk. Use of the integrative subtypes improves the prediction of late, distant relapse beyond what is possible with clinical covariates (nodal status, tumour size, tumour grade and immunohistochemical subtype). These findings highlight opportunities for improved patient stratification and biomarker-driven clinical trials.

Prognosis in patients diagnosed with loco-regional failure of breast cancer: 34 years longitudinal data from the Stockholm-Gotland cancer registry

RATIONALE

Survival after loco-regional failure (LRF) of breast cancer was investigated at the population level.

METHODS

Using the Stockholm cancer registry, 2698 patients diagnosed with LRF between 1980 and 2014 were identified and divided into three cohorts by year of LRF diagnosis. Post-relapse event-free survival (EFS) and overall survival (OS) were analyzed separately in local and loco-regional relapses and compared across the cohorts by Kaplan-Meier method. Relative survival was estimated and Poisson regression models, adjusted for clinically relevant prognostic factors, were fitted for excess mortality ratio calculation. Age-related survival trends were also explored.

RESULTS

Among 1922 patients diagnosed with local relapse, 1032 (54%) EFS events and 931 (48%) deaths were registered. A significant improvement in EFS (p < 0.001) and OS (p < 0.001) was demonstrated in tumors that recurred locally in the years 1990-1999 and 2000-2014 compared with 1980-1989, regardless of age at relapse (≤ 60 years; > 60 years). In women with loco-regional relapse, 557 out of 776 (72%) experienced a post-relapse event and 522 (67%) died. Significantly longer EFS and OS were seen over time in the whole group (p < 0.001 and p = 0.003, respectively) and in younger (p < 0.001; p < 0.001) but not in older women (p = 0.55; p = 0.80). Relative survival was consistent with OS and a statistically significant decrease in mortality after loco-regional recurrence over time was seen only in women aged ≤ 60 years.

CONCLUSIONS

Survival after loco-regional failure of breast cancer has improved over time, especially in younger women.

Clinicopathological Features and Prognostic Factors Affecting Survival Outcomes in Isolated Locoregional Recurrence of Breast Cancer: Single-Institutional Series

Purpose

The purpose of this study was to investigate the clinicopathologic features and prognostic factors affecting outcome in patients with isolated locoregional recurrence of breast cancer (ILRR).

Methods

We retrospectively analyzed the medical records of 104 patients who were diagnosed with ILRR and underwent curative surgery from January 2000 to December 2010 at Samsung Medical Center.

Results

Among 104 patients, 43 (41%) underwent total mastectomy and 61 (59%) underwent breast-conserving surgery for primary breast cancer. The median time from initial operation to ILRR was 35.7 months (4.5–132.3 months). After diagnosis of ILRR, 45 (43%) patients were treated with mastectomy, 41 (39%) with excision of recurred lesion, and 18 (17%) with node dissection. During a median follow-up of 8.9 years, the 5-year overall survival was 77% and 5-year distant metastasis-free survival (DMFS) was 54%. On multivariate analysis, younger age (< 35 years), higher stage, early onset of elapse (≤ 24 months), lymph node recurrences, and subtype of triple negative breast cancer (TNBC) were found to be independently associated with DMFS. Patients in the no chemotherapy group showed a longer DMFS after surgery for ILRR than those treated with chemotherapy (median 101.5 vs. 48.0 months, p = 0.072) but without statistical significance.

Conclusion

Our analysis showed that younger age (< 35 years), higher stage, early onset of relapse (≤ 24 months), lymph node recurrence, and subtype of TNBC are the worst prognostic factors for ILRR.

Prognostic Impact of Time to Ipsilateral Breast Tumor Recurrence after Breast Conserving Surgery

Background

The poor prognosis of patients who experience ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery (BCS) is established. A short time between primary cancer and IBTR is a prognostic factor but no clinically relevant threshold was determined. Classification of IBTR may help tailor treatment strategies.

Purpose

We determined a specific time frame, which differentiates IBTR into early and late recurrence, and identified prognostic factors for patients with IBTR at time of the recurrence.

Methods

We analyzed 2209 patients with IBTR after BCS. We applied the optimal cut-points method for survival data to determine the cut-off times to IBTR. A subgroup analysis was performed by hormone receptor (HR) status. Survival analyses were performed using a Cox proportional hazard model to determine clinical features associated with distant-disease-free survival (DDFS) after IBTR. We therefor built decision trees.

Results

On the 828 metastatic events observed, the majority occurred within the first 3 months after IBTR: 157 in the HR positive group, 98 in the HR negative group. We found different prognostic times to IBTR: 49 months in the HR positive group, 33 in the HR negative group. After multivariate analysis, time to IBTR was the first discriminant prognostic factor in both groups (HR 0.65 CI95% [0.54–0.79] and 0.42 [0.30–0.57] respectively). The other following variables were significantly correlated with the DDFS: the initial number of positive lymph nodes for both groups, the initial tumor size and grade for HR positive tumors.

Conclusion

A short interval time to IBTR is the strongest factor of poor prognosis and reflects occult distant disease. It would appear that prognosis after IBTR depends more on clinical and histological parameters than on surgical treatment. A prospective trial in a low-risk group of patients to validate the safety of salvage BCS instead of mastectomy in IBTR is needed.

The Globalization of Cooperative Groups

The National Cancer Institute (NCI)-supported adult cooperative oncology research groups (now officially Network groups) have a longstanding history of participating in international collaborations throughout the world. Most frequently, the US-based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the United States, and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the United States or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the United States and Canada, such as those frequently associated with infections in Latin America, Asia, and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to US policies that restrict drug distribution outside the United States. This article serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future.

Chemotherapy for isolated locoregional recurrence of breast cancer (CALOR): a randomised trial

BACKGROUND

Patients with isolated locoregional recurrences (ILRR) of breast cancer have a high risk of distant metastasis and death from breast cancer. We aimed to establish whether adjuvant chemotherapy improves the outcome of such patients.

METHODS

The CALOR trial was a pragmatic, open-label, randomised trial that accrued patients with histologically proven and completely excised ILRR after unilateral breast cancer who had undergone a mastectomy or lumpectomy with clear surgical margins. Eligible patients were enrolled from hospitals worldwide and were centrally randomised (1:1) to chemotherapy (type selected by the investigator; multidrug for at least four courses recommended) or no chemotherapy, using permuted blocks, and stratified by previous chemotherapy, oestrogen-receptor and progesterone-receptor status, and location of ILRR. Patients with oestrogen-receptor-positive ILRR received adjuvant endocrine therapy, radiation therapy was mandated for patients with microscopically involved surgical margins, and anti-HER2 therapy was optional. The primary endpoint was disease-free survival. All analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00074152.

FINDINGS

From Aug 22, 2003, to Jan 31, 2010, 85 patients were randomly assigned to receive chemotherapy and 77 were assigned to no chemotherapy. At a median follow-up of 4·9 years (IQR 3·6-6 ·0), 24 (28%) patients had disease-free survival events in the chemotherapy group compared with 34 (44%) in the no chemotherapy group. 5-year disease-free survival was 69% (95% CI 56-79) with chemotherapy versus 57% (44-67) without chemotherapy (hazard ratio 0·59 [95% CI 0·35-0·99]; p=0·046). Adjuvant chemotherapy was significantly more effective for women with oestrogen-receptor-negative ILRR (pinteraction=0·046), but analyses of disease-free survival according to the oestrogen-receptor status of the primary tumour were not statistically significant (pinteraction=0·43). Of the 81 patients who received chemotherapy, 12 (15%) had serious adverse events. The most common adverse events were neutropenia, febrile neutropenia, and intestinal infection.

INTERPRETATION

Adjuvant chemotherapy should be recommended for patients with completely resected ILRR of breast cancer, especially if the recurrence is oestrogen-receptor negative.

FUNDING

US Department of Health and Human Services, Swiss Group for Clinical Cancer Research (SAKK), Frontier Science and Technology Research Foundation, Australian and New Zealand Breast Cancer Trials Group, Swedish Cancer Society, Oncosuisse, Cancer Association of South Africa, Foundation for Clinical Research of Eastern Switzerland (OSKK), Grupo Español de Investigación en Cáncer de Mama (GEICAM), and the Dutch Breast Cancer Trialists' Group (BOOG).

Possible clinical cure of metastatic breast cancer: lessons from our 30-year experience with oligometastatic breast cancer patients and literature review

BACKGROUND

Metastatic breast cancer (MBC) is generally incurable. However, 10-20-year relapse-free survival of MBC is approximately 2%, implying that at least a small subset of MBC patients achieve prolonged survival. We therefore analyzed long-term outcome in a particular subset, i.e., oligometastatic breast cancer (OMBC).

METHODS

Data of OMBC subjects (N = 75) treated in our institution from April 1980 to March 2010 were retrospectively analyzed. OMBC was identified as: one or 2 organs involved with metastatic lesions (excluding the primary lesion resectable by surgery), fewer than 5 lesions per metastasized organ, and lesion diameter less than 5 cm. Patients were generally treated with systemic chemotherapy first, and those who achieved complete response (CR) or partial response (PR) were further treated, if applicable, with local therapy (surgical or radiation therapy) to maintain CR or to induce no evidence of clinical disease (NED), with additional systemic therapy.

RESULTS

Median follow-up duration was 103 (6-329) months. Single or 2 organs were involved in, respectively, 44 (59%) and 31 (41%) cases with metastatic lesions, 48% of which were visceral. In cases where effects of systemic therapy, possibly in combination with other treatments, were evaluated (N = 68), CR or PR was achieved in 33 (48.5%) or 32 (47.1%), respectively, with overall response rate (ORR: CR + PR) of 95.6% (N = 65). In cases receiving multidisciplinary treatment (N = 75), CR or NED (CR/NED), or PR was induced in 48 (64.0%) or 23 (30.7%) cases, respectively, with ORR (CR/NED + PR) of 94.7% (N = 71). CR rates (60.5%) with systemic therapy and CR/NED rates (79.5%) with multidisciplinary treatment were significantly better in subjects with a single involved organ than in those with two involved organs (P = 0.047 and 0.002, systemic only or multidisciplinary treatments, respectively). Medians estimated by Kaplan-Meier method were: overall survival (OS) of 185.0 months and relapse-free interval (RFI) of 48.0 months. Estimated outcomes were: OS rates (OSR) of 59.2% at 10 years and 34.1% at 20 years, and relapse-free rates (RFR) of 27.4% at 10 years and 20 years. No disease progression was observed after 101.0 months as RFR. Cases with single organ involvement (N = 44) showed significantly better outcomes (OSR of 73% at 10 years and 52% at 20 years, RFR of 42% at 10 years and 20 years). Those who received local therapies (N = 35) also showed better prognosis: OSR of 82% at 10 years and 53% at 20 years, RFR of 38% at 10 years and 20 years. Three cases (4%) survived for their lifetime without relapse after achieving CR or NED, our definition of clinical cure. Multivariate analysis revealed factors favoring better prognosis as: none for OS, and single organ involvement with metastasis, administration of local treatment, and shorter disease-free interval (DFI) (P = 0.030, 0.039, and 0.042, respectively) for RFR. Outcomes in OMBC in literature were OSR of 35-73% at 10 years and 26-52% at 20 years, and RFR of 27-42% at 10 years and 26-42% at 20 years.

CONCLUSIONS

The present analyses clearly indicate that OMBC is a distinct subgroup with long-term prognosis superior to MBC, with reasonable provability for clinical cure. Further prospective studies to better characterize OMBC are warranted to improve prognosis in MBC.

Prognostic factors affecting the outcome of salvage radiotherapy for isolated locoregional recurrence after mastectomy

OBJECTIVES

To evaluate the prognostic factors affecting the outcome of salvage radiotherapy for isolated locoregional recurrence after mastectomy.

METHODS

Between May 1988 and April 2002, 65 breast cancer patients underwent radiotherapy as a component of salvage treatment for isolated locoregional recurrence after mastectomy. The sites of failure were as follows: chest wall in 37 patients, regional lymph nodes (LNs) in 23 patients, and combined chest wall and LNs in 5 patients. None of the patients had previously been treated with radiation. Thirty-nine patients had surgical resection, and 55 patients received systemic chemotherapy and/or hormonal therapy for recurrent disease. In 51 cases (78.5%), the chest wall and ipsilateral regional lymphatics including supraclavicular, axillary, and internal mammary LNs were irradiated. Median dose was 50.4 Gy (range: 50-71.5). Median duration of follow-up was 52 months (range: 2-206).

RESULTS

The 5-year overall survival rate was 48.1%. On multivariate analysis, patients without initial nodal involvement had better overall survival (P = 0.0118). The 5-year locoregional progression-free survival rate was 69.8%, and time to recurrence (>36 months vs. < or =36 months) had an influence on the outcome with borderline significance (P = 0.0775). The 5-year distant metastasis-free survival rate was 42.1%. Lack of systemic therapy after recurrence (P = 0.0089) and age <50 years at recurrence (P = 0.0145) were significant prognostic factors predicting poor distant metastasis-free survival.

CONCLUSIONS

Radiotherapy for isolated locoregional relapse after mastectomy achieved locoregional control in about two-thirds of patients. Major pattern of failure was distant relapse, and systemic therapy is warranted to prevent secondary dissemination.

Recurrent breast cancer: treatment strategies for maintaining and prolonging good quality of life

BACKGROUND

Recurrent breast cancer remains a challenge for interdisciplinary treatment even though new therapeutic options are available.

METHODS

The PubMed database was selectively searched for articles that appeared from 1999 to 2009 and contained the key words "breast cancer," "recurrence," "metastatic," "advanced," and "treatment". Further sources consulted for this review included the German S3 guideline, the treatment recommendations of the German AGO-Mamma group, the NCCN guidelines, and the Cochrane database.

RESULTS

Locoregional recurrences are treated with curative intent. Metastatic breast cancer must be treated on an individualized basis: The treatment should be continued as long as its benefits for the individual patient outweigh its adverse side effects. Endocrine treatment is indicated for all patients whose tumors are hormone-receptor positive or of unknown receptor status and who have enough time for a response to be seen. Chemotherapy should be given if the tumor is hormone-receptor negative, if a rapid response is urgently needed, or if endocrine treatment has failed to produce a response. Combination chemotherapy improves response rates and prolongs progression-free survival, yet it does not prolong overall survival in comparison to monochemotherapy. In HER2-positive patients, first-line treatment with trastuzumab and monochemotherapy prolongs overall survival. Other treatment options include angiogenesis inhibitors, various tyrosine kinases inhibitors, radiotherapy, bisphosphonates, surgical or other ablative treatment of metastases, or a combination of these approaches, applied either simultaneously or consecutively.

CONCLUSIONS

While locoregional recurrences of breast cancer should be treated with curative intent, breast cancer with distant metastases is currently not curable. It is treated with the intention of restoring and maintaining good quality of life and relieving symptoms due to the metastases, rather than prolonging survival.

Prognosis after ipsilateral breast tumor recurrence and locoregional recurrences in patients treated by breast-conserving therapy in five National Surgical Adjuvant Breast and Bowel Project protocols of node-negative breast cancer

PURPOSE

Locoregional failure (LRF) after breast-conserving therapy (BCT) is associated with increased risk of distant disease and death. The magnitude of this risk has not been adequately characterized in patients with lymph node-negative disease.

PATIENTS AND METHODS

Our study population included 3,799 women randomly assigned to five National Surgical Adjuvant Breast and Bowel Project protocols of node-negative disease (ie, B-13, B-14, B-19, B-20, and B-23) who underwent lumpectomy and whole breast irradiation with or without adjuvant systemic therapy. Cumulative incidences of ipsilateral breast tumor recurrence (IBTR) and other locoregional recurrence (oLRR) were calculated, along with distant-disease-free interval (DDFI) and overall survival (OS) after these events. Cox models were employed to model mortality by using clinical and pathologic factors jointly with these events.

RESULTS

Four hundred nineteen patients (11.0%) experienced LRF: 342 (9.0%) experienced IBTR, and 77 (2.0%) experienced oLRR. The 12-year cumulative incidences of IBTR and oLRR in patients treated with adjuvant systemic therapy were 6.6% and 1.8%, respectively. Overall, 37.1% of IBTRs and 72.7% of oLRRs occurred within 5 years of diagnosis. Older age, black race, higher body mass index (BMI), larger tumors, and occurrence of IBTR or oLRR were significantly associated with increased mortality. The 5-year OS after IBTR and oLRR were 76.6% and 34.9%, respectively. Adjusted hazard ratios for mortality associated with IBTR and oLRR were significantly higher in estrogen receptor (ER)-negative patients than in ER-positive patients (P = .002 and P < .0001, respectively). Patients with early LRF had worse OS and DDFI than those with later-occurring LRF.

CONCLUSION

Although LRF is uncommon in patients with node-negative breast cancer who are treated with lumpectomy, radiation, and adjuvant systemic therapy, those who do develop LRF have substantially worse OS and DDFI.

Progress on BIG 1-02/IBCSG 27-02/NSABP B-37, a prospective randomized trial evaluating chemotherapy after local therapy for isolated locoregional recurrences of breast cancer

BACKGROUND

The utility of chemotherapy for women who experience a locoregional recurrence after primary treatment of early breast cancer remains an open question. An international collaborative trial is being conducted by the Breast International Group (BIG), the International Breast Cancer Study Group (IBCSG), and the National Surgical Adjuvant Breast and Bowel Project (NSABP) to determine the effectiveness of cytotoxic therapy for these patients, either alone or in addition to selective use of hormonal therapy and trastuzumab.

METHODS

The trial population includes women who have had a previous diagnosis of invasive breast cancer treated by mastectomy or breast-conserving surgery, but subsequently develop an isolated local and/or regional ipsilateral invasive recurrence. Excision of all macroscopic tumor without evidence of systemic disease is required for study entry. Patients are randomized to receive chemotherapy or no chemotherapy; type of chemotherapy is not protocol-specified. Radiation, hormonal therapy, and trastuzumab are given as appropriate. The primary endpoint is disease-free survival (DFS). Quality-of-life measurements are collected at baseline, and then at 9 and 12 months. The accrual goal is 977 patients.

RESULTS

This report describes the characteristics of the first 99 patients. Sites of recurrence at study entry were: breast (56%), mastectomy scar/chest wall (35%), and regional lymph nodes (9%). Two-thirds of patients have estrogen-receptor-positive recurrences.

CONCLUSION

This is the only trial actively investigating the question of "adjuvant" chemotherapy in locally recurrent breast cancer. The case mix of accrual to date indicates a broad representation of this patient population.