Selecting breast cancer patients with T1-T2 tumors and one to three positive axillary nodes at high postmastectomy locoregional recurrence risk for adjuvant radiotherapy

Post-Operative Radiation in Early Breast Cancer with N1 Disease: 10-Year Follow-Up

Post-operative radiotherapy for post-menopausal women with early breast cancer and N1 disease is controversial. Although locoregional control is improved, overall survival (OS) benefit is unclear. The clinical benefit of post-operative irradiation in this group of patients over 10 years was reviewed. We aimed to evaluate the OS, disease-free survival (DFS), and factors affecting OS and DFS. A retrospective review of 191 post-menopausal women with early breast cancer and N1 disease from 2004 to 2011 was performed. Demographics, post-operative histology, adjuvant treatment, OS, and DFS were evaluated. Post-operative radiation was given to 95 of 191 women (49.7%). Younger age at diagnosis (p < 0.001), a greater number of involved nodes (p = 0.004), lymphovascular invasion (LVI), and a higher tumor grade (p = 0.001) were more likely in women who received post-operative radiation. Nodal radiation did not improve 10-year DFS (p = 0.084) or OS (p = 0.203). Post-operative nodal radiation was associated with significant improvement in 10-year OS in women who received only hormonal therapy (p = 0.047) and no other systemic therapy. Women with unfavorable risk factors were more likely to receive post-operative radiation, likely due to a perceived higher risk of recurrence. Nodal radiation did not significantly improve 10-year DFS or OS in early breast cancer patients with N1 disease, and the benefit was not clearly demonstrated. However, in those who were on hormonal therapy, radiotherapy was beneficial in improving overall survival.

Assessment of Postmastectomy Radiation Therapy Receipt by Age and Association With Outcomes in Women With Breast Cancer

PURPOSE

Postmastectomy radiation therapy (PMRT) reduces locoregional recurrence (LRR) and improves overall survival (OS) in patients with breast cancer. Young age has been recognized as a risk factor for LRR. The primary objective of this study was to determine if recommendations for PMRT differed among patients younger than 50 years as compared to women aged 50 years or older.

METHODS

We reviewed medical records of patients with breast cancer who underwent mastectomy with or without PMRT from 2010 through 2018. Univariable and multivariable models were used to estimate the association of age with PMRT.

RESULTS

Of 2471 patients, 839 (34%) were <50 years; 1632 (66%) were ≥50 years. Patients <50 years had a higher percentage of grade 3 tumors, hormone receptor (HR) negative and/or Her-2/neu positive tumors, clinical stage T2/T3 tumors, and nodal involvement. Compared with patients ≥50 years, patients <50 years were more likely to undergo PMRT (OR 1.57; P = .001) and regional node irradiation (RNI) to the internal mammary nodes. Advanced clinical and pathologic stage, invasive tumor histology, the presence of lymphovascular invasion, and treatment with systemic chemotherapy were predictors of PMRT receipt for patients <50 years (P < .05). PMRT was associated with improved OS and recurrence free survival (RFS) among all patients (P < .01).

CONCLUSION

Patients <50 years were more likely to undergo PMRT and to receive RNI to the internal mammary nodes but were also more likely to have other risk factors for recurrence that would warrant a PMRT recommendation. PMRT improved OS and RFS for all patients.

Post-mastectomy radiotherapy for women with early breast cancer and one to three positive lymph nodes

BACKGROUND

Continual improvement in adjuvant therapies has resulted in a better prognosis for women diagnosed with breast cancer. A surrogate marker used to detect the spread of disease after treatment of breast cancer is local and regional recurrence. The risk of local and regional recurrence after mastectomy increases with the number of axillary lymph nodes affected by cancer. There is a consensus to use radiotherapy as an adjuvant treatment after mastectomy (postmastectomy radiotherapy (PMRT)) in women diagnosed with breast cancer and found to have disease in four or more positive axillary lymph nodes. Despite data showing almost double the risk of local and regional recurrence in women treated with mastectomy and found to have one to three positive lymph nodes, there is a lack of international consensus on the use of PMRT in this group.

OBJECTIVES

To assess the effects of PMRT in women diagnosed with early breast cancer and found to have one to three positive axillary lymph nodes.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov up to 24 September 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs). The inclusion criteria included women diagnosed with breast cancer treated with simple or modified radical mastectomy and axillary surgery (sentinel lymph node biopsy (SLNB) alone or those undergoing axillary lymph node clearance with or without prior SLNB). We included only women receiving PMRT using X-rays (electron and photon radiation), and we defined the radiotherapy dose to reflect what is currently being recommended (i.e. 40 Gray (Gy) to 50 Gy in 15 to 25/28 fractions in 3 to 5 weeks. The included studies did not administer any boost to the tumour bed. In this review, we excluded studies using neoadjuvant chemotherapy as a supportive treatment before surgery.

DATA COLLECTION AND ANALYSIS

We used Covidence to screen records. We collected data on tumour characteristics, adjuvant treatments and the outcomes of local and regional recurrence, overall survival, disease-free survival, time to progression, short- and long-term adverse events and quality of life. We reported on time-to-event outcome measures using the hazard ratio (HR) and subdistribution HR. We used Cochrane's risk of bias tool (RoB 1), and we presented overall certainty of the evidence using the GRADE approach.

MAIN RESULTS

The RCTs included in this review were subgroup analyses of original RCTs conducted in the 1980s to assess the effectiveness of PMRT. Hence, the type and duration of adjuvant systemic treatments used in the studies included in this review were suboptimal compared to the current standard of care. The review involved three RCTs with a total of 829 women diagnosed with breast cancer and low-volume axillary disease. Amongst the included studies, only a single study pertained to the modern-day radiotherapy practice. The results from this one study showed a reduction of local and regional recurrence (HR 0.20, 95% confidence interval (CI) 0.13 to 0.33, 1 study, 522 women; low-certainty evidence) and improvement in overall survival with PMRT (HR 0.76, 95% CI 0.60 to 0.97, 1 study, 522 women; moderate-certainty evidence). One of the other studies using radiotherapy techniques that do not reflect modern-day practice reported on disease-free survival in women with low-volume axillary disease (subdistribution HR 0.63, 95% CI 0.41 to 0.96, 1 study, 173 women). None of the included studies reported on PMRT side effects or quality-of-life outcome measures.

AUTHORS' CONCLUSIONS

Based on one study, the use of PMRT in women diagnosed with breast cancer and low-volume axillary disease indicated a reduction in locoregional recurrence and an improvement in survival. There is a need for more research to be conducted using modern-day radiotherapy equipment and methods to support and supplement the review findings.

Risk factors to identify the indication for regional nodal irradiation in T1-2N1M0 breast cancer: A joint analysis of 4,243 real-world cases from two institutions

Purpose

The aim of this study is to evaluate the role of regional nodal irradiation (RNI) in patients with T1-2N1M0 breast cancer and to identify the subgroup that could benefit from RNI.

Methods and materials

A total of 4,243 women with pT1-2N1M0 breast cancer treated at two institutions in China were retrospectively reviewed. Survival rates were calculated by the Kaplan-Meier method and compared by the log-rank test. The association of risk factors with survival outcomes was evaluated using multivariable proportional hazards regression.

Results

A total of 932 patients (22.0%) received RNI. At a median follow-up of 5.9 years, the 5-year locoregional recurrence (LRR), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS) rates were 4.0% and 7.2% (P = 0.001), 13.2% and 10.6% (P = 0.465), 85.0% and 84.7% (P = 0.131), and 93.9% and 92.8% (P = 0.004) in the RNI and non-RNI groups, respectively. Multivariate analysis revealed that RNI was an independent prognostic factor for lower LRR (P = 0.001) and longer DFS (P = 0.013). Patients were stratified into low-, intermediate-, and high-risk groups based on the eight non-therapeutic risk factors. RNI significantly decreased the 5-year LRR (2.2% vs. 7.0%, P = 0.001) and improved the 5-year DFS (88.8% vs. 84.9%, P = 0.015) and OS (95.8% vs. 93.9%, P = 0.010) in the intermediate-risk group. However, neither the low-risk group nor the high-risk group had survival benefit from RNI.

Conclusion

T1-2N1M0 breast cancer is a heterogeneous disease. We found that RNI only improved survival in the intermediate-risk group. It might be omitted in low-risk patients, and the role of RNI in high-risk patients needs further study.

Influence of age as a continuous variable on the prognosis of patients with pT1-2N1 breast cancer

PURPOSE

To assess the influence of age as a continuous variable on the prognosis of pT1-2N1 breast cancer and examine its decision-making value for postmastectomy radiotherapy (PMRT).

METHODS

We retrospectively evaluated 5438 patients with pT1-2N1 breast cancer after mastectomy in 11 hospitals. A multivariable Cox proportional hazards regression model with penalized splines was used to examine the relationship between age and oncologic outcomes.

RESULTS

The median follow-up was 67.0 months. After adjustments for confounding characteristics, nonsignificant downward trend in locoregional recurrence (LRR) risk was observed with increasing age (P-non-linear association = 0.640; P-linear association = 0.078). A significant non-linear association was found between age and disease-free survival (DFS) and overall survival (OS) (P-non-linear association <0.05; P-linear association >0.05, respectively). The DFS and OS exhibited U-shaped relationships, with the hazard ratios (HRs), reaching a nadir at 50 years old. A decreased risk of LRR with PMRT vs. no PMRT (HR = 0.304, 95% CI: 0.204-0.454) was maintained in all ages. The HR of PMRT vs. no PMRT for DFS and OS gradually increased with age. In patients ≤50 years old, PMRT was independently associated with favorable LRR, DFS, and OS, all P < 0.05). In patients >50 years old, PMRT was independently associated with reduced LRR (P = 0.004), but had no effect on DFS or OS.

CONCLUSIONS

Age was an independent prognostic factor for pT1-2N1 breast cancer; PMRT provided survival benefits for patients ≤50 years old, but not for patients >50 years old.

Validation of a prognostic scoring system for postmastectomy locoregional recurrence in breast cancer

Background

To date, it remains unclear which patients with breast cancer (BC) benefit from post-mastectomy radiotherapy (PMRT). Cheng et al. developed and validated a scoring system based on 4 prognostic factors for locoregional recurrence (LRR) to identify patients in need for PMRT. These factors include age, estrogen receptor status, lymphovascular status and number of affected axillary lymph nodes.

Purpose

To validate the scoring system for LRR in BC developed by Cheng et al. by using an independent BC database.

Methods and materials

We retrospectively identified 1989 BC cases, treated with mastectomy (ME) with or without PMRT at the University Hospitals Leuven between 2000 and 2007. The primary endpoint was 5-year locoregional control rate with and without PMRT, according to the LRR score.

Results

Median follow-up time was 11.4 years. After excluding patients with missing variables 1103 patients were classified using the LRR scoring system: 688 (62.38%) patients were at low risk of recurrence (LRR score 0–1), 335 (30.37%) patients were at intermediate risk of recurrence (LRR score 2–3) and 80 (7.25%) patients were at high risk of recurrence (LRR score ≥4). 5-year locoregional control rates with and without PMRT were 99.20% versus 99.21% (p = 0.43) in the low-risk group; 98.24% versus 85.74% (p < 0.0001) in the intermediate-risk group and 96.87% versus 85.71% (p = 0.10) in the high-risk group respectively.

Conclusion

Our validation of the LRR scoring system suggests it can be used to point out patients that would benefit from PMRT. We recommend further validation of this scoring system by other independent institutions before application in clinical practice.

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Post-mastectomy radiotherapy.

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Scoring system by Cheng et al.

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Based on 4 factors.

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Age, estrogen receptor, lymphovascular status, affected axillary lymph nodes.

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Intermediate and high-risk patients could benefit from post-mastectomy radiotherapy.

A multi-institutional prediction model to estimate the risk of recurrence and mortality after mastectomy for T1-2N1 breast cancer

Background

Post‐mastectomy radiation therapy (PMRT) in women with pathologic stage T1‐2N1M0 breast cancer is controversial.

Methods

Data from five North American institutions including women undergoing mastectomy without neoadjuvant therapy with pT1‐2N1M0 breast cancer treated from 2006 to 2015 were pooled for analysis. Competing‐risks regression was performed to identify factors associated with locoregional recurrence (LRR), distant metastasis (DM), overall recurrence (OR), and breast cancer mortality (BCM).

Results

A total of 3532 patients were included for analysis with a median follow‐up time among survivors of 6.8 years (interquartile range [IQR], 4.5–9.5 years). The 2154 (61%) patients who received PMRT had significantly more adverse risk factors than those patients not receiving PMRT: younger age, larger tumors, more positive lymph nodes, lymphovascular invasion, extracapsular extension, and positive margins (p < .05 for all). On competing risk regression analysis, receipt of PMRT was significantly associated with a decreased risk of LRR (hazard ratio [HR], 0.21; 95% confidence interval [CI], 0.14–0.31; p < .001) and OR (HR, 0.76; 95% CI, 0.62–0.94; p = .011). Model performance metrics for each end point showed good discrimination and calibration. An online prediction model to estimate predicted risks for each outcome based on individual patient and tumor characteristics was created from the model.

Conclusions

In a large multi‐institutional cohort of patients, PMRT for T1‐2N1 breast cancer was associated with a significant reduction in locoregional and overall recurrence after accounting for known prognostic factors. An online calculator was developed to aid in personalized decision‐making regarding PMRT in this population.

In a large multi‐institutional cohort of patients, post‐mastectomy radiation therapy (PMRT) for T1‐2N1 breast cancer was associated with a significant reduction in locoregional and overall recurrence after accounting for known prognostic factors. An online calculator was developed to aid in personalized decision‐making regarding PMRT in this population.

Postmastectomy radiotherapy for all node positive patients: The case against

Postmastectomy radiotherapy (PMRT) is accepted as the standard of care for women with early breast cancer with 4 or more involved axillary nodes. However the role of PMRT in women with 1-3 involved nodes remains controversial and guidelines vary. We present the arguments against advocating postmastectomy radiotherapy for all women with node positive breast cancer.

A Prognostic Risk Stratification Model to Identify Potential Population Benefiting From Postmastectomy Radiotherapy in T1-2 Breast Cancer With 1-3 Positive Axillary Lymph Nodes

Background and Objectives

To establish a prognostic stratification nomogram for T1–2 breast cancer with 1–3 positive lymph nodes to determine which patients can benefit from postmastectomy radiotherapy (PMRT).

Methods

A population-based study was conducted utilizing data collected from the Surveillance, Epidemiology, and End Results database. Chi-square test or Fisher exact test was used to compare the distribution of characteristics. Cox analysis identified significant prognostic factors for survival. A prognostic stratification model was constructed by R software. Propensity score matching was applied to balance characteristics between PMRT cohort and control cohort. Kaplan-Meier method was performed to evaluate the performance of stratification and the benefits of PMRT in the total population and three risk groups.

Results

The overall performance of the nomogram was good (3-year, 5-year, 10-year AUC were 0.75, 0.72 and 0.67, respectively). The nomogram was performed to excellently distinguish low-risk, moderate-risk, and high-risk groups with 10-year overall survival (OS) of 86.9%, 73.7%, and 62.7%, respectively (P<0.001). In the high-risk group, PMRT can significantly better OS with 10-year all-cause mortality reduced by 6.7% (P = 0.027). However, there was no significant survival difference between PMRT cohort and control cohort in low-risk (P=0.49) and moderate-risk groups (P = 0.35).

Conclusion

The current study developed the first prognostic stratification nomogram for T1–2 breast cancer with 1–3 positive axillary lymph nodes and found that patients in the high-risk group may be easier to benefit from PMRT.

Risk-Adapted Postmastectomy Radiotherapy Decision Based on Prognostic Nomogram for pT1-2N1M0 Breast Cancer: A Multicenter Study

PURPOSE

The aim of this study was to develop a widely accepted prognostic nomogram and establish a risk-adapted PMRT strategy based on locoregional recurrence for pT1-2N1M0 breast cancer.

METHODS AND MATERIALS

A total of 3,033 patients with pT1-2N1M0 breast cancer treated at 6 participating institutions between 2000 and 2016 were retrospectively reviewed. A nomogram was developed to predicted locoregional recurrence-free survival (LRFS). A propensity score-matched (PSM) analyses was performed in risk-adapted model.

RESULTS

With the median follow-up of 65.0 months, the 5-year overall survival (OS), disease free survival (DFS) and LRFS were 93.0, 84.8, and 93.6%, respectively. There was no significant difference between patients who received PMRT or not for the entire group. A nomogram was developed and validated to estimate the probability of 5-year LRFS based on five independent factors including age, primary tumor site, positive lymph nodes number, pathological T stage, and molecular subtype that were selected by a multivariate analysis of patients who did not receive PMRT in the primary cohort. According to the total nomogram risk scores, the entire patients were classified into low- (40.0%), moderate- (42.4%), and high-risk group (17.6%). The 5-year outcomes were significantly different among these three groups (P<0.001). In low-risk group, patients who received PMRT or not both achieved a favorable OS, DFS, and LRFS. In moderate-risk group, no differences in OS, DFS, and LRFS were observed between PMRT and no PMRT patients. In high-risk group, compared with no PMRT, PMRT resulted in significantly different OS (86.8 vs 83.9%, P = 0.050), DFS (77.2 vs 70.9%, P = 0.049), and LRFS (90.8 vs. 81.6%, P = 0.003). After PSM adjustment, there were no significant differences in OS, DFS, and LRFS in low-risk and moderate-risk groups. However, in the high-risk group, PMRT still resulted in significantly better OS, DFS and improved LRFS.

CONCLUSIONS

The proposed nomogram provides an individualized risk estimate of LRFS in patients with pT1-2N1M0 breast cancer. Risk-adapted PMRT for high-risk patients is a viable effective strategy.

Effectiveness of the AJCC 8th edition staging system for selecting patients with T1-2N1 breast cancer for post-mastectomy radiotherapy: a joint analysis of 1986 patients from two institutions

Background

The role of post-mastectomy radiotherapy (PMRT) in the treatment of patients with T1–2N1 breast cancer is controversial. This study’s purpose was to evaluate the risk of recurrence of T1–2N1 breast cancer and the efficacy of PMRT in low-, medium- and high-risk groups of patients.

Methods

Post-mastectomy patients with T1–2N1 breast cancer were restaged according to the American Joint Committee on Cancer Staging Manual, 8th edition (AJCC 8th ed.) staging system. Recurrence scores were generated using prognostic factors identified for loco-regional recurrence and distant metastasis in patients without PMRT, and three risk groups were identified. Rates of loco-regional recurrence and distant metastasis were calculated with a competing risk model and compared using Gray’s test. Disease-free survival and overall survival were calculated using the Kaplan-Meier method and compared using the log-rank test. The Cox proportional hazards regression model was used for the multivariate analysis.

Results

Data from 1986 patients (1521without PMRT; 465 with PMRT) were analyzed. Patients without PMRT were stratified into low-, intermediate- and high-risk groups by age, tumor location, AJCC 8th ed. stage, number of positive nodes and lympho-vascular invasion. The 5-year loco-regional recurrence rate and distant metastasis rates for the three risk groups were significant at 2.5, 5.4 and 16.2% (p <  0.001) respectively, and 4.9, 8.4 and 18.6% (p <  0.001) respectively. In the high-risk group, loco-regional recurrence (p <  0.001), and distant metastasis (p = 0.044) were significantly reduced, and disease free survival (p = 0.004), and overall survival (p = 0.029) were significantly improved after PMRT. In the low- and intermediate-risk groups, PMRT had no significant effect on loco-regional recurrence (p = 0.268), distant metastasis (p = 0.252), disease free survival (p = 0.608) or overall survival (p = 0.986).

Conclusion

Our results showed no benefits of PMRT in the low-risk group, and thus, omitting PMRT radiotherapy in this population could be considered.

Identifying factors impacting the efficacy of postmastectomy radiotherapy in patients with early-stage breast cancer and one to two positive lymph nodes

INTRODUCTION

In women with T1-2 breast cancer and one to two positive axillary lymph nodes (LN) at low risk for recurrence, postmastectomy radiation therapy (PMRT) may provide insufficient benefit to justify its toxicity. This study evaluated the interaction of factors associated with overall survival (OS) after PMRT in these patients.

METHODS

The National Cancer Database was queried for women with T1-2 breast cancer undergoing mastectomy with one to two positive LN identified on lymphadenectomy. Patients were grouped according to number of positive LN and then stratified by PMRT use. Differences in OS were evaluated.

RESULTS

Multivariable modeling demonstrated an interaction effect of age on the efficacy of PMRT. In patients more than or equal to 60 years old, PMRT was associated with improved survival when adjusting for age and tumor grade in patients with 1 to 2 positive LN (risk ratio = 0.62, 95% confidence interval = 0.40-0.93, P = .018). In patients less than 60 years old, tumor size and grade, but not PMRT, were associated with improved OS.

CONCLUSION

For women with T1-2 breast cancer and one to two positive LN, PMRT's association with OS is influenced by age, tumor grade, and number of positive LN. PMRT appears to be associated with improvements in OS in older patients, but not younger patients, regardless of tumor size or nodal status.

One-step prepectoral breast reconstruction with porcine dermal matrix-covered implant: a protective technique improving the outcome in post-mastectomy radiation therapy setting

Background

Post-mastectomy radiotherapy (PMRT) applied on implant-assisted immediate breast reconstruction (IBR) involves a marked increase in complication rate. The recent opportunity of performing an ADM-assisted prepectoral breast reconstruction (PPBR) raised the hypotesis of a protective interaction between ADM and periprosthetic tissues under PMRT.

Methods

We performed a retrospective monocentric analysis of a cohort of consecutively treated patients undergone one-step PPBR between January 2015 and September 2018. The aim is to examine complication rate and aesthetic satisfaction of patients, in order to evaluate if this reconstructive technique could be recommendable in PMRT setting. Group 1 comprised 158 patients not submitted to PMRT and Group 2 twenty-eight patients undergone PMRT.

Results

All post-operative complications were not statistically different between the two groups, except for capsular contracture (P=0.011). We obtained very high percentages in all BREAST-Q categories in Group 2 patients: satisfaction with breasts 86.8±13.9, satisfaction with implants 6.5±3.0, high satisfaction for no adverse effects of radiation 15.7±6.8. According to multivariate analysis no risk factor was significantly associated with complications.

Conclusions

We may conclude that one-step PPBR with porcine ADM followed by PMRT is well tolerated, with no significant risk of adverse outcomes, at least in the short-term follow-up. These promising outcomes warrant further studies to examine the existence of a protective effect due to ADM integration with subcutaneous tissue.

Post-mastectomy Radiotherapy in T1-2 Breast Cancer Patients With One to Three Lymph Node Metastases: A Propensity Score Matching Analysis

Background and Objectives: Whether post-mastectomy radiotherapy (PMRT) could improve prognosis for T1-2 breast cancer patients with one to three lymph node metastases remains controversial. The present study aimed to determine the significance of PMRT in patients with T1-2N1M0 breast cancer. Methods: Data of 45,646 patients from the Surveillance, Epidemiology, and End Results (SEER) database were analyzed; 12,585 matched patients were divided into a PMRT group and non-radiotherapy group (no-PMRT), respectively, using the propensity score matching method. Univariate and multivariate analyses were performed to determine the prognostic factors of breast cancer, and subgroup analysis was performed according to the number of lymph node metastases. Results: With the median follow-up of 62 months, 5-year cancer-specific survival was 91.48% in the PMRT group and 91.88% in the no-PMRT group (P = 0.405). PMRT did not improve the breast cancer-specific survival (BCSS) in patients with stage T1-2N1M0 (HR = 0.99, 95% CI = 0.92-1.06, P = 0.715). In subgroup analysis, radiotherapy improved the BCSS in patients with three nodes positive, with the 5-year BCSS at 88.5% in the radiation group and 86.6% in the no-radiation group (HR = 0.78, 95% CI = 0.65-0.90, P < 0.001). In patients with two nodes positive, 5-year BCSS was 90.3% in the PMRT group and 89.5% in the no-PMRT group, with no significant difference between the two groups (HR = 0.96, 95% CI = 0.85-1.09, P = 0.552). In patients with one node positive, 5-year BCSS was higher in the no-PMRT group (92.1%) than that in the PMRT group (90.8%); radiotherapy increased the cancer-related death compared with those who did not receive it (HR = 1.21, 95% CI = 1.08-1.36, P = 0.002). Conclusion: The benefit of PMRT in T1-2N1M0 patients was obviously different, and the recommendation of PMRT for this population should be individualized. PMRT should be considered for patients with three nodes positive, should be suggested cautiously in those with two nodes positive, and could be omitted in those with one node positive.

Axillary management for young women with breast cancer varies between patients electing breast-conservation therapy or mastectomy

PURPOSE

Axillary treatment strategies for the young woman with early-stage, clinically node-negative breast cancer undergoing upfront surgery found to have 1-3 positive sentinel lymph nodes (SLNs) differ significantly after BCT and mastectomy. Here we compare axillary lymph node dissection (ALND) and regional nodal irradiation (NRI) rates between women electing breast-conservation therapy (BCT) versus mastectomy.

METHODS

From 2010 to 2016, women age < 50 years with clinical T1-T2N0 breast cancer having upfront surgery and found to have a positive SLN were identified. ALND and/or NRI receipt were compared between groups.

RESULTS

192 women undergoing BCT and 165 undergoing mastectomy were identified (median age: 44 years). 5.2% (10/192) of women undergoing BCT had an ALND versus 87% (144/165) of women undergoing mastectomy (p < 0.01). NRI was given to 48% (78/165) of mastectomy patients compared to 30% (57/192) of BCT patients (p < 0.01). Of the 75 mastectomy patients with 1-2 total positive lymph nodes after completion ALND, 44% received NRI. Women undergoing mastectomy were significantly more likely to receive both ALND and NRI than women undergoing BCS (45% vs 6%, p < 0.01).

CONCLUSION

Young cT1-2N0 breast cancer patients found to have 1-3 SLN metastases received ALND, NRI, and combined ALND/NRI more frequently if they elected mastectomy over BCT. Use of both ALND and postmastectomy radiotherapy (PMRT) in this population could be reduced in the future by omitting ALND in patients for whom the need for PMRT is clear with the finding of 1-2 SLN metastases.

Late locoregional complications associated with adjuvant radiotherapy in the treatment of breast cancer: Systematic review and meta-analysis

This systematic review with meta-analysis addressed late locoregional complications associated with adjuvant radiotherapy (RT) in breast cancer. Among 2120 titles, ten comparative studies in patients undergoing surgery vs surgery and radiotherapy reporting complications were evaluated. RT was associated with an increased risk of capsular contracture and decreased the mobility of the upper limb. A borderline association of lymphedema risk using RT was noted in the random-effects model but was significant in the fixed-effects model.

Individualized Prediction of Survival Benefit from Postmastectomy Radiotherapy for Patients with Breast Cancer with One to Three Positive Axillary Lymph Nodes

PURPOSE

There still exist some arguments regarding the use of postmastectomy radiotherapy (PMRT) for patients with breast cancer carrying one to three positive axillary lymph nodes considering the heterogeneity of this cohort. Here, we developed a prognostic nomogram to estimate the probability of long-term outcome in patients receiving or not receiving PMRT in order to assist in making individually locoregional treatment decisions for this particular cohort.

METHODS

Altogether, 20,336 women, aged 18 to 80 years, diagnosed with breast cancer, and carrying one to three positive nodes were identified in the Surveillance, Epidemiology, and End Results (SEER) database. We applied multivariant Cox hazard model to determine the impact of covariates on disease-specific survival (DSS) and overall survival (OS). Then, the nomogram was built accordingly. Internal and external validations were performed to examine the accuracy of nomograms.

RESULTS

Age of diagnosis, tumor grade, size, estrogen and progesterone receptor status, and number of positive nodes were independent factors of DSS and OS in the multivariate analysis. Incorporating these factors into the constructed nomogram showed high accuracy when predicting 5- and 10-year survival, with internally and externally bootstrap-corrected concordance indexes in the range of 0.6 to 0.8.

CONCLUSION

Besides the number of involved nodes, extra variables existed as predictors of survival outcomes in this cohort; therefore, the recommendation of PMRT or no PMRT requires comprehensive consideration. This clinically validated nomogram provided a useful tool that could aid decision making by estimating DSS and OS benefits from PMRT, useful in predicting 5- and 10-year DSS and OS for patients with one to three positive nodes after mastectomy.

IMPLICATIONS FOR PRACTICE

This study evaluated population-based data to identify prognostic factors associated with patients with breast cancer with one to three lymph nodes and help clinicians to weigh the benefit of postmastectomy radiotherapy (PMRT). Surveillance, Epidemiology, and End Results (SEER) data were used to develop a prognostic nomogram to predict the likelihood of long-term survival with and without PMRT in order to optimize the individual locoregional control strategy for this particular cohort. This clinically validated nomogram provides a useful tool to predict 5- and 10-year disease-specific survival and overall survival for patients with one to three positive nodes and can aid tailored clinical decision making by estimating predicted benefit from PMRT.

Local and regional recurrence following mastectomy in breast cancer patients with 1-3 positive nodes: implications for postmastectomy radiotherapy volume

PURPOSE

To determine the necessity of postmastectomy radiotherapy (PMRT) and which regions would be at risk for recurrence, we evaluated local and regional recurrence in breast cancer patients with 1-3 positive nodes and a tumor size of <5 cm.

MATERIALS AND METHODS

We retrospectively analyzed data of 133 female breast cancer patients with 1-3 positive nodes, and a tumor size of <5 cm who were treated with mastectomy followed by adjuvant systemic therapy between 2007 and 2016. The median follow-up period was 57 months (range, 12 to 115 months). Most patients (82.7%) were treated with axillary lymph node dissection. Adjuvant chemotherapy, endocrine therapy, and trastuzumab therapy were administered to 124 patients (93.2%), 112 (84.2%), and 33 (24.8%), respectively. The most common chemotherapy regimen was anthracycline and cyclophosphamide followed by taxane (71.4%).

RESULTS

Three patients (2.3%), 8 (6.0%), and 12 (9.0%) experienced local, regional, and distant failures, respectively. The 5-year cumulative risk of local recurrence, regional recurrence, distant metastasis, and disease-free survival was 3.1%, 8.0%, 11.7%, and 83.4%, respectively. There were no statistically significant clinicopathologic factors associated with local recurrence. Lymphovascular invasion (univariate p = 0.015 and multivariate p = 0.054) was associated with an increased risk of regional recurrence.

CONCLUSION

Our study showed a very low local recurrence in patients with 1-3 positive nodes and tumor size of <5 cm who were treated with mastectomy and modern adjuvant systemic treatment. The PMRT volume need to be tailored for each patient's given risk for local and regional recurrence, and possible radiation-related toxicities.

Comparison of Immediate versus Delayed DIEP Flap Reconstruction in Women Who Require Postmastectomy Radiotherapy

BACKGROUND

The authors investigated aesthetic outcome and patient satisfaction in women who have undergone deep inferior epigastric artery perforator (DIEP) flap reconstruction in the setting of postmastectomy radiotherapy. Patients who underwent DIEP flap reconstruction without postmastectomy radiotherapy were the control group.

METHODS

Participants who had undergone DIEP flap reconstruction between September 1, 2009, and September 1, 2014, were recruited, answered the BREAST-Q, and underwent three-dimensional surface-imaging. A panel assessed the aesthetic outcome by reviewing these images.

RESULTS

One hundred sixty-seven women participated. Eighty women (48 percent) underwent immediate DIEP flap reconstruction and no postmastectomy radiotherapy; 28 (17 percent) underwent immediate DIEP flap reconstruction with postmastectomy radiotherapy; 38 (23 percent) underwent simple mastectomy, postmastectomy radiotherapy, and DIEP flap reconstruction; and 21 (13 percent) underwent mastectomy with temporizing implant, postmastectomy radiotherapy, and DIEP flap reconstruction. Median satisfaction scores were significantly different among the groups (p < 0.05). Post hoc comparison demonstrated that women who had an immediate DIEP flap reconstruction were significantly less satisfied if they had postmastectomy radiotherapy. In women requiring radiotherapy, those undergoing delayed reconstruction after a simple mastectomy were most satisfied, but there was no significant difference between the immediate DIEP flap and temporizing implant groups. Median panel scores differed among groups, being significantly higher if the immediate reconstruction was not subjected to radiotherapy. There was no significant difference in panel assessment among the three groups of women who had received radiotherapy.

CONCLUSIONS

Patients who avoid having their immediate DIEP flap reconstruction irradiated are more satisfied and have better aesthetic outcome than those who undergo postmastectomy radiotherapy. In women requiring radiotherapy and who wish to have an immediate or "delayed-immediate" reconstruction, there were no significant differences in panel or patient satisfaction. Therefore, immediate DIEP flap reconstruction or mastectomy with temporizing implant then DIEP flap surgery are acceptable treatment pathways in the context of post-mastectomy radiotherapy.

Impact of postmastectomy radiotherapy on the outcomes of breast cancer patients with T1-2 N1 disease : An individual patient data analysis of three clinical trials

PURPOSE

To assess the impact of postmastectomy radiotherapy (PMRT) on overall survival and relapse-free survival among breast cancer patients with T1-T2 N1 disease who received standard adjuvant systemic therapy.

METHODS

This is an individual patient data pooled analysis of 1053 breast cancer patients referred for adjuvant therapy in three clinical trials (BIG 02/98, BCIRG001, and BCIRG005). Overall survival was assessed according to whether or not patients received adjuvant radiotherapy through Kaplan-Meier analysis. Univariate and multivariate analyses of predictors of overall and relapse-free survival were conducted through Cox regression analysis.

RESULTS

Locoregional relapse rates (after a median follow up of 116 months) were 5.6% among patients who received adjuvant radiotherapy vs. 6.6% among patients who did not receive adjuvant radiotherapy. Actuarial 5‑ and 10-year locoregional relapse-free survival rates were 94 and 93%, respectively, among patients who did not receive adjuvant radiotherapy versus 95 and 92% among patients who received adjuvant radiotherapy. The following factors were associated with worse overall survival in multivariate Cox regression analysis: age < 40 years (P < 0.0001), T2 stage (P = 0.004), higher lymph node ratio (P < 0.0001), and negative hormone receptor status (P < 0.0001). Likewise, the following factors were predictive of shorter locoregional relapse-free survival: age ≤ 40 (P < 0.0001), no PMRT (P = 0.034), fluorouracil/adriamycin/cyclophosphamide (FAC) chemotherapy (P = 0.001), and higher T stage (P = 0.002).

CONCLUSION

The current analysis does not show a beneficial impact of PMRT on overall or relapse-free survival among patients with T1-T2 N1 disease who received standard adjuvant systemic therapy. There is, however, evidence of improvement in locoregional relapse-free survival with PMRT. These findings need to be prospectively validated.

Impact of Regional Nodal Irradiation on the Outcomes of N1 Breast Cancer Patients Referred for Adjuvant Treatment: A Patient-Level Pooled Analysis of 2 Clinical Trials

PURPOSE

To evaluate the impact of regional nodal irradiation (RNI) among N1 operable breast cancer patients who underwent adequate axillary dissection and received adjuvant chemotherapy.

PATIENTS AND METHODS

This is a pooled analysis of 812 breast cancer patients referred for adjuvant systemic therapy in 2 prospective randomized studies: NCT00174655 (BIG 02/98) and NCT00312208 (BCIRG005). Overall survival was assessed according to whether patients received supraclavicular and/or internal mammary radiotherapy through Kaplan-Meier estimates. Univariate and multivariate analyses of variables affecting overall and relapse-free survival were performed through Cox regression analysis. Additionally, recurrence rates were analyzed according to regional irradiation patterns.

RESULTS

Regional relapse rates (after a median follow-up of 76 months) were 1.5% in both groups of patients who received or did not receive supraclavicular radiotherapy. The risk of regional recurrence was 0.7% in patients who received internal mammary node radiotherapy versus 1.6% in patients who did not receive internal mammary node radiotherapy. The following factors were associated with worse overall survival in multivariate Cox regression analysis: age < 40 years (P < .0001), > T1 stage (P = .003), and negative hormone receptor status (P = .002). Neither supraclavicular nor internal mammary radiotherapy was associated with improvement in overall or relapse-free survival in Cox regression analysis.

CONCLUSION

The current analysis does not endorse the routine use of supraclavicular or internal mammary radiotherapy among N1 operable breast cancer patients who have undergone adequate dissection of axillary lymph nodes and who have received standard adjuvant systemic therapy. Given the limited power and potential selection bias of the current analysis, further prospective studies are needed to tackle this research question.

Multidisciplinary Management of the Axilla in Patients with cT1-T2 N0 Breast Cancer Undergoing Primary Mastectomy: Results from a Prospective Single-Institution Series

BACKGROUND

The after mapping of the axilla: radiotherapy or surgery (AMAROS) trial concluded that for patients with cT1-2 N0 breast cancer and one or two positive sentinel lymph nodes (SLNs), axillary radiotherapy (AxRT) provides equivalent locoregional control and a lower incidence of lymphedema compared with axillary lymph node dissection (ALND). The study prospectively assessed how often ALND could be replaced by AxRT in a consecutive cohort of patients undergoing mastectomy for cT1-2 N0 breast cancer.

METHODS

In November 2015, our multidisciplinary group agreed to omit routine intraoperative SLN evaluation for cT1-2 N0 patients undergoing upfront mastectomy and potentially eligible for postmastectomy radiation therapy (PMRT), including those 60 years of age or younger and those older than 60 years with high-risk features. Patients with one or two positive SLNs on final pathology were reviewed to determine whether PMRT including the full axilla was an appropriate alternative to ALND.

RESULTS

From November 2015 to December 2016, 154 patients met the study criteria, and 114 (74%) formed the final study cohort. Intraoperative SLN evaluation was omitted for 76 patients (67%). Of these patients, 20 (26%) had one or two positive SLNs, and 14 of these patients received PMRT + AxRT as an alternative to ALND. Three patients returned for ALND, and three patients were observed. On univariate analysis, tumor size, LVI, number of positive lymph nodes, and receipt of chemotherapy were associated with receipt of PMRT.

CONCLUSIONS

For the majority of patients with one or two positive SLNs, ALND was avoided in favor of PMRT + AxRT. With appropriate multidisciplinary strategies, intraoperative evaluation of the SLN and immediate ALND can be avoided for patients meeting the AMAROS criteria and eligible for PMRT.

Factors Influencing Axillary Node Metastasis in Breast Cancer

Aims and Background

The status of the axillary lymph nodes at the time of diagnosis has been accepted as one of the most important prognostic factors for the overall and disease-free survival of patients with breast cancer. The aim of our study was to determine which factors influence axillary node involvement in invasive breast cancer.

Methods

The data presented here were obtained from 344 patients who were treated for invasive breast cancer at the Department of Radiation Oncology, Uludag University Medical College, Bursa, Turkey. Possible prognostic factors were categorized as patient related and tumor related. The Mann-Whitney U test was used for univariate analysis and logistic regression was used for multivariate analysis.

Results

In univariate analysis, a familial cancer history (P = 0.0042), age <40 years (P = 0.0276), higher T stage (P <0.0000), nipple involvement (P = 0.0345), skin involvement (P = 0.0270), perineural invasion (P = 0.0231), and lymphatic vessel invasion (P <0.0000) were correlated with increased axillary node involvement. A higher incidence of ≥4 involved lymph nodes was associated with higher T stage (P = 0.0004), nipple involvement (P = 0.0292), presence of an extensive intraductal component (P = 0.0023), skin involvement (P = 0.0008), perineural invasion (P = 0.0523), and lymphatic vessel invasion (P <0.0000) in univariate analysis. In multivariate analysis, age <40 years (P = 0.0454), cancer history within the family (P = 0.0024), higher T stage (P = 0.0339), lymphatic vessel invasion (P = 0.0003), and perineural invasion (P = 0.0408) were found to be independent factors for axillary lymph node positivity. Age <40 years (P = 0.0221), perineural invasion (P = 0.0408), and an extensive intraductal component (P = 0.0132) were associated with an increased incidence of ≥4 involved nodes in the logistic regression analysis. In patients with breast cancer, the incidence of axillary lymph node involvement was independently influenced by age <40 years, presence of cancer history within the family, higher T stage, lymphatic vessel invasion, and perineural invasion.

Conclusions

In conclusion, absence of familial cancer history, presence of lymphatic vessel invasion, higher T stage, and age below 40 years independently increased the risk of axillary node involvement. Presence of perineural invasion and lymphatic vessel invasion, age below 40, and an extensive intraductal component of more than 25% independently affected the risk of having ≥4 nodes involved. Patients characterized by these factors may be classified into a higher risk group for nodal involvement, but more data are needed to define factors that can help in the decision-making regarding the omission of axillary treatment.

Most Breast Cancer Patients with T1-2 Tumors and One to Three Positive Lymph Nodes Do Not Need Postmastectomy Radiotherapy

BACKGROUND/OBJECTIVE

Guidelines concur that postmastectomy radiation therapy (PMRT) in T1-2 tumors with one to three positive (+) lymph nodes (LNs) decreases locoregional recurrence (LRR) but advise limiting PMRT to patients at highest risk to balance against potential harms. In this study, we identify the risks of LRR after mastectomy in patients with T1-2N1 disease, treated with modern chemotherapy, and identify predictors of LRR when omitting PMRT.

METHODS

Patients with T1-2N1 breast cancer undergoing mastectomy between 1995 and 2006 were categorized by receipt of PMRT. The Chi square test compared the clinicopathologic features between both groups, and Kaplan-Meier and Cox regression analysis was used to determine the rates of LRR, recurrence-free survival (RFS), and overall survival (OS).

RESULTS

Overall, 1087 patients (924 no PMRT, 163 PMRT) were included in the study, with a median follow-up of 10.8 years (range 0-21). We identified 63 LRRs (56 no PMRT, 7 PMRT), and 10-year rates of LRR with and without PMRT were 4.0% and 7.0%, respectively. Patients receiving PMRT were younger (p = 0.019), had larger tumors (p = 0.0013), higher histologic grade (p = 0.029), more positive LNs (p < 0.0001), lymphovascular invasion (LVI) (p < 0.0001), extracapsular nodal extension (p < 0.0001), and macroscopic LN metastases (p < 0.0001). There was no difference in LRR, RFS, or OS between groups. On multivariate analysis, age < 40 years (p < 0.0001) and LVI (p < 0.0001) were associated with LRR in those not receiving PMRT.

CONCLUSION

Consistent with the guidelines, 85% of patients with T1-2N1 were spared PMRT at our center, while maintaining low LRR. Age < 40 years and the presence of LVI are significantly associated with LRR in those not receiving PMRT.

Should all breast cancer patients with four or more positive lymph nodes who underwent modified radical mastectomy be treated with postoperative radiotherapy? A population-based study

Postmastectomy radiotherapy (PMRT) has become a standard adjuvant postoperative therapy for breast cancer patients with four or more positive lymph nodes. However, some studies have demonstrated that some subgroups of the breast cancer patients with four or more positive lymph nodes did not benefit substantially from PMRT. Therefore, it is of great necessity to identify whether all breast cancer patients with four or more positive lymph nodes who underwent modified radical mastectomy be treated with PMRT. In our study, we first established a prognostic model using the Surveillance Epidemiology and End Results (SEER) database between 1998 and 2001. Univariate and multivariate Cox models were used to assess the prognostic factors, and five risk factors individually associated with prognosis including AJCC stage, AJCC T, Grade, ER status, PR status. Prognostic index of PMRT were defined as the number of risk factor (NRF). The NRF scores correlated well with overall survival of PMRT even if the patients were in the sub-poor prognosis group. Then the prognostic model was validated using the SEER database between 2006 and 2009, and the same results were obtained. In conclusion, different from others studies, our study demonstrated that all patients with four or more positive lymph nodes after modified radical mastectomy need to be treated with PMRT ever if the patients belonged to AJCC T4 in a poor prognosis group.

Breast Conservation Therapy Versus Mastectomy in Patients with T1-2N1 Triple-Negative Breast Cancer: Pooled Analysis of KROG 14-18 and 14-23

Purpose

The aim of this study is to compare the treatment outcomes of breast conserving surgery (BCS) plus radiotherapy (RT) versus mastectomy for patients with pT1-2N1 triple-negative breast cancer (TNBC).

Materials and Methods

Using two multicenter retrospective studies on breast cancer, a pooled analysis was performed among 320 patients with pT1-2N1 TNBC. All patients who underwent BCS (n=212) receivedwhole breast RTwith orwithoutregional nodal RT,while nonewho underwent mastectomy (n=108)received it. All patients received taxane-based adjuvant chemotherapy. The median follow-up periods were 65 months in the BCS+RT group, and 74 months in the mastectomy group.

Results

The median age of all patients was 48 years (range, 24 to 70 years). Mastectomy group had more patients with multiple tumors (p < 0.001), no lymphovascular invasion (p=0.001), higher number of involved lymph node (p=0.028), and higher nodal ratio ≥ 0.2 (p=0.037). Other characteristics were not significantly different between the two groups. The 5-year locoregionalrecurrence-free, disease-free, and overall survivalrates of BCS+RT group versus mastectomy group were 94.6% versus 87.7%, 89.5% versus 80.4%, and 95.0% versus 87.8%, respectively, and the differences were statistically significant after adjusting for covariates (p=0.010, p=0.006, and p=0.005, respectively).

Conclusion

In pT1-2N1 TNBC, breast conservation therapy achieved better locoregional recurrencefree, disease-free, and overall survival rates compared with mastectomy.

A prognostic score model to determine which breast cancer patients with 1-3 positive lymph nodes after modified radical mastectomy should receive radiotherapy

There is no consensus on the indication for postmastectomy radiotherapy (PMRT) in breast cancer patients with one to three positive lymph nodes. To identify patients for whom PMRT may be indicated, we used a prognostic score model with the SEER database to retrospectively analyze 8049 patients with one to three positive lymph nodes who underwent mastectomy with or without PMRT between 2010 and 2013. Kaplan-Meier analysis showed that PMRT patients had better overall survival (OS) than no-PMRT patients (P < 0.001); however, there was no difference in cancer-specific survival (CSS) (P = 0.530). Multivariate analysis with Cox regression showed that grade (P < 0.001), tumor size (P < 0.001), and progesterone receptor status (P < 0.001) were independent prognostic factors for OS. To diminish bias, we used 1:1 propensity score matching analysis and prognosis score model, which revealed that PMRT patients had better OS and CSS than no-PMRT patients (P < 0.001). In a concrete subgroup analysis of PMRT patients, significant improvements in OS were observed in patients scoring 0, 1, or 2. PMRT patients scoring 2 also had improved CSS. The magnitude of the OS and CSS difference with PMRT correlated with the prognostic score (P < 0.001). These results suggest PMRT in breast cancer patients with one to three positive lymph nodes should be based on patient factors, tumor biology, and prognostic score.

Genomic alterations and radioresistance in breast cancer: an analysis of the ProfiLER protocol

BACKGROUND

Breast cancer (BC) patients with comparable prognostic features have heterogeneous outcomes, party related to a possible radiotherapy resistance leading to local-regional recurrences (LRR). The objective of the present study was to identify predictive molecular biomarkers of LRR of BC.

PATIENTS AND METHODS

Genetic profile of 146 BC patients' tumours included in the ProfiLER clinical trial (NC01774409) between 2013 and 2016 were analysed using next-generation-sequencing and comparative-genomic-hybridization tests. Patients and tumour characteristics were retrospectively collected and analysed for association with genomic rearrangements (mutations, amplification, deletions). Only gene alterations observed in >3% of the tumours were selected.

RESULTS

A total of 193 genomic rearrangements were identified, and 16 were observed in >3% of tumours. One was statistically correlated to the risk of local relapse. A median loco-regional progression-free survival (LRPFS) of 23.6 years was reported for PIK3CA mutation carriers (n = 31, 21.2%) versus 9.9 years for PIK3CA wild-type patients (HR 0.27, 95% CI 0.12-0.65, P = 0.002 in univariate analysis). PIK3CA mutation was identified as an independent protective factor on LRR using multivariate analysis (HR 0.29, 95% CI 0.09-0.99, P = 0.047). All other mutations, amplifications or deletions were not found associated with LRPFS.

CONCLUSION

PIK3CA mutation was associated with a lower risk of local relapse in this population of BCs. This is consistent with recent studies suggesting PIK3CA to be part of biological pathways impacting the radiosensitivity.

The curative effects of radiotherapy-based therapies for human epidermal growth factor receptor 2-positive breast cancer: A meta-analysis

AIM

This meta-analysis was designed to fully assess the curative effects of radiotherapy-based therapies for human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC).

METHODS

English articles were retrieved through searching Cochrane library, PubMed, and Embase databases updated to February 2017. Studies were selected based on the inclusion and exclusion criteria. The curative effects of radiotherapy-based therapies forHER2+ BC patients were assessed using hazard rates (HRs) or odds ratios (ORs), as well as their 95% confidence intervals (CIs). In addition, Egger test was used to assess publication bias, followed by sensitivity analysis. All statistic methods were conducted using R 3.12 software.

RESULTS

A total of 9 eligible studies were included into this meta-analysis, which involved 2236 HER2+ BC patients. Egger test showed that the eligible studies had no publication bias (t = 2.198, P = .05918). Sensitivity analysis demonstrated that the results were stable. HER2+ BC patients in radiotherapy group had lower locoregional recurrences than those in other groups. Moreover, meta-analysis showed that no significant difference was found between HER2+ BC patients in radiotherapy group and other groups on the 1-year overall survival (P = 0.5263, I = 65.4%), 3-year overall survival (P = 0.4591, I = 0), and 5-year overall survival (P = 0.06277, I = 0).

CONCLUSION

Radiotherapy-based therapies might have certain advantages in treating HER2+ BC patients.

Role of postmastectomy radiotherapy in early-stage (T1-2N0-1M0) triple-negative breast cancer: a systematic review

Triple-negative breast cancer (TNBC), which represents 15%–20% of all breast cancers, is defined by the absence of estrogen receptor (ER) and progesterone receptor (PR) and overexpression of human epidermal growth factor receptor 2 (HER2). Owing to the absence of specific therapeutic targets and its aggressive biologic characteristics, TNBC patients often experience a high risk of disease progression and poor overall survival. Furthermore, TNBC exhibits an early pattern of recurrence with a peak recurrence risk at 2–3 years after surgery. Currently, chemotherapy continues to be the mainstay in TNBC patients; however, such treatment leaves them associated with a high rate of local and systemic relapses even in early-stage (T1–2N0–1M0). Therefore, in early-stage disease, greater emphasis is placed on locoregional treatments, based on radiation therapy (RT) after surgery, to reduce local and systemic relapses. However, there are no specific treatment guidelines for early-stage (T1–2N0–1M0) TNBC patients. In this review, we discuss the type of surgery received and the relevant adverse clinicopathologic factors and underlying BRCA1 mutation status regarding the influence of tailing postmastectomy radiotherapy (PMRT). In addition, we assess the role of PMRT in early-stage (T1–2N0–1M0) TNBC patients.

Outcomes in Patients with pT1-T2, pN0-N1 Breast Cancer After Conservative Surgery and Whole-breast Radiotherapy

AIM

To evaluate locoregional recurrence, overall survival, disease-free survival and prognostic influence of the number of positive lymph nodes and other variables in breast cancer treatment.

PATIENTS AND METHODS

A total of 377 patients with pT1-T2, pN0-N1 invasive breast carcinoma treated from 2005 to 2013 were retrospectively evaluated. Patients underwent conservative surgery followed by whole-breast radiotherapy. Clavicular region irradiation was not performed.

RESULTS

With a median follow-up of 4 years, locoregional recurrence rate was 3.4% (nodal recurrence=1.06%). Expression of progesterone receptors was significantly associated with better disease-free survival, tumor size (T>2 cm) with poorer disease-free survival, locoregional recurrence and poorer overall survival; the presence of three nodal metastases was related to significantly poorer overall survival (p=0.024).

CONCLUSION

Whole-breast adjuvant radiotherapy without nodal irradiation after breast-conserving surgery led to low rate of locoregional recurrence and high rates of overall survival and disease-free survival in patients with pT1-T2 pN0-N1 breast cancer.

Postmastectomy Radiotherapy: An American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology Focused Guideline Update

PURPOSE

A joint American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology panel convened to develop a focused update of the American Society of Clinical Oncology guideline concerning use of postmastectomy radiotherapy (PMRT).

METHODS

A recent systematic literature review by Cancer Care Ontario provided the primary evidentiary basis. The joint panel also reviewed targeted literature searches to identify new, potentially practice-changing data.

RECOMMENDATIONS

The panel unanimously agreed that available evidence shows that PMRT reduces the risks of locoregional failure (LRF), any recurrence, and breast cancer mortality for patients with T1-2 breast cancer with one to three positive axillary nodes. However, some subsets of these patients are likely to have such a low risk of LRF that the absolute benefit of PMRT is outweighed by its potential toxicities. In addition, the acceptable ratio of benefit to toxicity varies among patients and physicians. Thus, the decision to recommend PMRT requires a great deal of clinical judgment. The panel agreed clinicians making such recommendations for individual patients should consider factors that may decrease the risk of LRF, attenuate the benefit of reduced breast cancer-specific mortality, and/or increase risk of complications resulting from PMRT. When clinicians and patients elect to omit axillary dissection after a positive sentinel node biopsy, the panel recommends that these patients receive PMRT only if there is already sufficient information to justify its use without needing to know additional axillary nodes are involved. Patients with axillary nodal involvement after neoadjuvant systemic therapy should receive PMRT. The panel recommends treatment generally be administered to both the internal mammary nodes and the supraclavicular-axillary apical nodes in addition to the chest wall or reconstructed breast.

Predictive Value of Primary Tumor Site for Loco-regional Recurrence in Early Breast Cancer Patients with One to Three Positive Axillary Lymphadenophy

Introduction: It remains controversial on high risks for early breast cancer patients with one to three axillary nodes after mastectomy who is predisposition to locoregional recurrence. The present study is to investigate the relationship between primary tumor site and loco-regional recurrence (LRR) and explore the predictive value of clinicopathological characteristics in LRR for early breast cancer patients with one to three positive axillary lymph nodes after mastectomy. Methods: We reviewed the clinical data of 656 consecutively diagnosed patients with pT_1-2N₁M₀ breast cancer who were treated in Sun Yat-sen University Cancer Center with radical operation without postoperative radiotherapy between March 1998 and December 2010. The primary tumor sites included outer quadrant in 455 patients (69.36%), inner quadrant in 156 patients (23.78%)and central quadrant in 45 patients (6.86%). LRR and LRR-free survival (LRFS) in combination with clinical and pathological features were analyzed to screen out patients with higher risk of LRR. Results: The median follow-up time was 64.9 months. The 5-, 10-year LRR for the cohort was 8.6% and 12.9%, respectively; the 5-, 10-year LRFS was 86.2% and 76.4%, respectively. Multivariate analyses showed that age of ≤35 years, inner quadrant tumor and non-luminal subtype were independent risk factors for LRR and LRFS. Patients with primary tumor in inner quadrant showed higher LRR and poorer LRFS when risk factors are ≥2 than those with tumors in other sites. Conclusions: Inner quadrant tumor was an independent predictor for LRR and LRFS in patients with early breast cancer and one to three positive axillary lymph nodes, which would be more accurate in combination with other prognostic indexes including patients' age, pathological T stage, Ki67 status, molecular subtypes.

Optimizing Breast Cancer Adjuvant Radiation and Integration of Breast and Reconstructive Surgery

Postmastectomy radiotherapy (PMRT) reduces the risk of locoregional and distant recurrence and improves overall survival in women with lymph node-positive breast cancer. Because of stage migration and improvements in systemic therapy and other aspects of breast cancer care, the absolute benefit of PMRT and regional nodal irradiation may be small in some favorable subsets of patients with very low nodal burden, and newer consensus guidelines do not mandate PMRT in all node-positive cases. The use and need for PMRT may considerably complicate breast reconstruction after mastectomy and therefore mandates multidisciplinary input that takes into account patient choice given potential risk of acute and long-term toxicities, benefits, life expectancy, the biology of the tumor, plans for systemic therapy, and actual tumor burden. Management of axillary lymph node metastases is changing with selective use of axillary lymph node dissection for advanced disease, sentinel lymph node biopsy alone for clinically and pathologic node-negative cases receiving mastectomy, and targeted axillary dissection alone among patients with eradication of initial biopsy-proven nodal metastases with neoadjuvant systemic therapy use. In general, when the need for PMRT is anticipated, autologous reconstruction should be delayed. This comprehensive article reviews the current indications and implications regarding integration of breast cancer surgery and timing of reconstruction with optimum radiation delivery to achieve the best possible patient outcomes.

Comparison of Treatment Outcomes between Breast Conserving Surgery Followed by Radiotherapy and Mastectomy Alone in Patients with T1-2 Stage and 1-3 Axillary Lymph Nodes in the Era of Modern Adjuvant Systemic Treatments

Purpose

The role of postmastectomy radiotherapy in the treatment of T1–2 primary tumor with 1–3 positive lymph nodes is controversial. We compared treatment outcomes between breast conserving surgery followed by radiotherapy (BCS+RT) and total mastectomy alone (TM) in the setting of modern adjuvant systemic treatments.

Methods

Patients with T1–2 primary breast cancer and 1–3 positive lymph nodes who were treated between 2001 and 2011 were divided into 2 groups based on the treatment approach: BCS+RT (n = 169) and TM (n = 117). All patients received adjuvant chemotherapy including taxanes. Adjuvant endocrine therapy was administered to patients with positive hormone receptors according to their menstrual status.

Results

During a median follow-up of 76.5 months, 21 patients (7.3%) experienced locoregional recurrence as the first event, including 7 patients (4.1%) in the BCS+RT group and 14 patients (12.0%) in the TM group. The 5-year cumulative incidence rate of locoregional recurrence was 2.5% for BCS+RT versus 9.5% for TM (p = 0.016). Competing risk regression analysis revealed that TM was associated with a relative risk for locoregional recurrence of 5.347 (p = 0.003). TM was also associated with a significantly lower 5-year disease-free survival rate compared with BCS+RT (hazard ratio, 2.024; 95% confidence interval, 1.090–3.759; p = 0.026).

Conclusion

To improve treatment outcomes for TM even after modern systemic treatments, postmastectomy radiotherapy might be required for patients with T1–2 primary breast cancer and 1–3 positive lymph nodes.

Postmastectomy Radiotherapy: An American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology Focused Guideline Update

Purpose A joint American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology panel convened to develop a focused update of the American Society of Clinical Oncology guideline concerning use of postmastectomy radiotherapy (PMRT). Methods A recent systematic literature review by Cancer Care Ontario provided the primary evidentiary basis. The joint panel also reviewed targeted literature searches to identify new, potentially practice-changing data. Recommendations The panel unanimously agreed that available evidence shows that PMRT reduces the risks of locoregional failure (LRF), any recurrence, and breast cancer mortality for patients with T1-2 breast cancer with one to three positive axillary nodes. However, some subsets of these patients are likely to have such a low risk of LRF that the absolute benefit of PMRT is outweighed by its potential toxicities. In addition, the acceptable ratio of benefit to toxicity varies among patients and physicians. Thus, the decision to recommend PMRT requires a great deal of clinical judgment. The panel agreed clinicians making such recommendations for individual patients should consider factors that may decrease the risk of LRF, attenuate the benefit of reduced breast cancer-specific mortality, and/or increase risk of complications resulting from PMRT. When clinicians and patients elect to omit axillary dissection after a positive sentinel node biopsy, the panel recommends that these patients receive PMRT only if there is already sufficient information to justify its use without needing to know additional axillary nodes are involved. Patients with axillary nodal involvement after neoadjuvant systemic therapy should receive PMRT. The panel recommends treatment generally be administered to both the internal mammary nodes and the supraclavicular-axillary apical nodes in addition to the chest wall or reconstructed breast.

Role of postmastectomy radiation therapy in breast cancer patients with T1-2 and 1-3 positive lymph nodes

Objective

To evaluate the role of radiotherapy (RT) in overall survival (OS) and disease-free survival in postmastectomy breast cancer patients with tumor size <5 cm, with 1–3 involved axillary lymph nodes (T1–2N1).

Patients and methods

We conducted a retrospective study of 89 postmastectomy patients with T1–2N1 disease between 2005 and 2015 at the Radiation Oncology Clinic of Kayseri Training and Research Hospital. Clinicopathologic, demographic, and laboratory findings, as well as treatment regimens were investigated. OS and disease-free survival as well as factors that can be valuable in the prognosis were evaluated.

Results

A total of 89 female patients with an average age of 53 years (range: 30–81 years) were included in the assessment. Five-year and 10-year local recurrence rates were found to be 6.6% in the RT group and 7.1% in the non-RT group. In the RT group, the mean OS was 110.3 months and progression-free survival was 104.4 months. In the non-RT group, the corresponding figures were 104.3 months and 92.1 months, respectively. Statistically significant correlation was observed between RT and the American Joint Committee on Cancer stage (P<0.001), histological type (P=0.013), tumor size (P<0.001), and lymph node metastasis (P<0.001). During the assessment, locoregional recurrence and/or distant metastasis occurred in nine patients (10%). Locoregional recurrence was observed mostly in patients with invasive ductal carcinoma, tumor >3.0 cm in size, grade II tumors, and perinodal invasion, and who were premenopausal at the time of diagnosis.

Conclusion

In T1–2N1 breast cancer patients who underwent modified radical mastectomy, when the effects of postmastectomy RT were evaluated, there were no differences in terms of OS and progression-free survival. In addition, when subgroup analysis was made, in patients with invasive ductal carcinoma, tumor diameter >2 cm, three lymph node metastasis, and stage 2b, postmastectomy RT was seen to be useful.

Postmastectomy Radiotherapy: An American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology Focused Guideline Update

A joint American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology panel convened to develop a focused update of the American Society of Clinical Oncology guideline concerning use of postmastectomy radiotherapy (PMRT).

METHODS

A recent systematic literature review by Cancer Care Ontario provided the primary evidentiary basis. The joint panel also reviewed targeted literature searches to identify new, potentially practice-changing data.

RECOMMENDATIONS

The panel unanimously agreed that available evidence shows that PMRT reduces the risks of locoregional failure (LRF), any recurrence, and breast cancer mortality for patients with T1-2 breast cancer with one to three positive axillary nodes. However, some subsets of these patients are likely to have such a low risk of LRF that the absolute benefit of PMRT is outweighed by its potential toxicities. In addition, the acceptable ratio of benefit to toxicity varies among patients and physicians. Thus, the decision to recommend PMRT requires a great deal of clinical judgment. The panel agreed clinicians making such recommendations for individual patients should consider factors that may decrease the risk of LRF, attenuate the benefit of reduced breast cancer-specific mortality, and/or increase risk of complications resulting from PMRT. When clinicians and patients elect to omit axillary dissection after a positive sentinel node biopsy, the panel recommends that these patients receive PMRT only if there is already sufficient information to justify its use without needing to know additional axillary nodes are involved. Patients with axillary nodal involvement after neoadjuvant systemic therapy should receive PMRT. The panel recommends treatment generally be administered to both the internal mammary nodes and the supraclavicular-axillary apical nodes in addition to the chest wall or reconstructed breast.

Predictive Value of Molecular Subtyping for Locoregional Recurrence in Early-Stage Breast Cancer with N1 without Postmastectomy Radiotherapy

Purpose

This study was designed to investigate the relationship between molecular subtype and locoregional recurrence (LRR) in patients with early-stage breast cancer with 1–3 positive axillary lymph nodes (ALNs) and improve the individualized indications for postmastectomy radiotherapy (PMRT).

Methods

The records of 701 patients with pT1-2N1M0 breast cancer who did not undergo PMRT were retrospectively analyzed. Tumors were subclassified as follows: luminal A, luminal B, human epidermal growth factor receptor 2 (HER2)-enriched, and basal-like subtypes. Multivariate Cox analysis was used to determine the risk of LRR associated with the different subtypes and to adjust for clinicopathologic factors.

Results

Luminal A, luminal B, HER2-enriched, and basal-like subtypes accounted for 51.2%, 28.0%, 8.1%, and 12.7% of cases, respectively. The median follow-up duration was 67 months (range, 9–156 months). Univariate analysis revealed that, compared with the luminal A subtype, the HER2-enriched and basal-like subtypes were associated with significantly higher 5-year LRR rates (5.6% vs. 21.6% and vs.15.7% respectively; p=0.002 each), lower 5-year LRR-free survival (LRFS) rates (90.6% vs. 73.8% and 78.5%, respectively; p=0.001 each), and poorer 5-year breast cancer-specific survival (BCSS) rates (93.7% vs. 82.2% [p=0.002] and 84.9% [p=0.001], respectively). Multivariate analysis revealed that the HER2-enriched and basal-like subtypes, age ≤35 years, a medial tumor, and pT2 stage were poor prognostic factors for LRR and LRFS; furthermore, 2 to 3 positive ALNs represented an independent prognostic factor affecting LRR. The 10-year LRR rates of patients with 0, 1, 2, 3, and 4 risk factors were 1.0%, 6.9%, 14.3%, 30.4%, and 54.3%, respectively (p<0.001); the 10-year BCSS rates were 86.6%, 88.5%, 84.4%, 79.7%, and 38.8%, respectively (p<0.001).

Conclusion

Molecular subtyping allows for individualized evaluation of LRR risk in patients with pT1-2N1M0 breast cancer. PMRT should be recommended for patients with ≥3 LRR risk factors.

Trends in the Application of Postmastectomy Radiotherapy for Breast Cancer With 1 to 3 Positive Axillary Nodes and Tumors ≤5 cm in the Modern Treatment Era: A Retrospective Korean Breast Cancer Society Report

Despite high-level evidence, the benefit of postmastectomy RT in these patients in recent years has not been fully elucidated. We investigated postmastectomy radiotherapy (RT) use and evaluated clinicopathologic and treatment factors influencing RT use in Korean women with pT1-2N1 breast cancer.We identified women diagnosed with pT1-2N1 breast cancer between 1994 and 2009 using the Korean Breast Cancer Registry. Factors associated with RT use were evaluated using logistic regression analysis. The median follow-up was 95 months.Of the 6196 women, 11.9% underwent postmastectomy RT. RT was applied more frequently in women with 3 positive lymph nodes (adjusted odds ratio [OR], 2.69) and larger tumors (OR per centimeter, 1.10). RT use was not significantly associated with well-established risk factors (e.g., tumor grade, hormone receptor status, and lymphovascular space invasion). Although RT utilization increased gradually during the study period (OR per year, 1.07), factors associated with RT were similar over time. The estimated 5-year overall survival increased significantly from 84.1% in 1994 to 2000 to 94.6% in 2005 to 2009.This population-based analysis revealed that the indications for postmastectomy RT in pT1-2N1 breast cancer in Korea are based solely on conventional anatomical factors, although their survival has increased significantly in the modern treatment era. There is a significant unmet need for better risk stratification in these patients and for tailored RT with the incorporation of tumor biology-associated factors.