Present-day locoregional control in patients with t1 or t2 breast cancer with 0 and 1 to 3 positive lymph nodes after mastectomy without radiotherapy

Does Post-Mastectomy Radiotherapy Confer Survival Benefits on Patients With 1-3 Clinically Positive Lymph Nodes Rendered Pathologically Negative After Neoadjuvant Systemic Chemotherapy: Consensus from A Pooled Analysis?

The advent of taxane-based chemotherapy has revolutionized breast cancer care. This advance has helped improve the response to downstaging tumors that might otherwise be inoperable. It has also helped in rendering clinically (cN+) positive lymph nodes (LNs) pathologically negative (ypN0). The standard of care for cN+ patients included post-mastectomy radiotherapy (PMRT), regardless of the response to neoadjuvant chemotherapy. However, PMRT in patients with 1-3 positive LNs still lacks definitive guidelines. Numerous retrospective results have been inconclusive about the benefit of PMRT on survival in patients with 1-3 positive LNs. This pooled analysis attempts to reach a consensus. The PubMed database was searched through October 2023. The search yielded 27 papers, of which 11 satisfied the inclusion criteria. The locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), and overall survival (OS) for each study were tabulated when given, and two groups were created, the PMRT and NO PMRT, respectively. The results were then pooled for analysis. The total number of patients was 8340, 4136 in the PMRT group, and 4204 in the NO PMRT group, respectively. The LRRFS, DFS, and OS were 96.9%, 82.1%, and 87.3% for the PMRT group and 93.2%, 79.6%, and 84.8% for the NO PMRT group, respectively. There was no statistical significance in LRRFS, DFS, or OS between the two groups (p = 0.61, p = 0.61, and p = 0.38, respectively). PMRT does not seem to confer survival benefits in patients with pN1 rendered ypN0 for stages T1-3. This pooled analysis's findings should be confirmed prospectively with a longer period of follow-up.

Long-term outcomes and predictors of recurrence in node-negative early stage breast cancer patients

BACKGROUND

We evaluated the outcomes, and risk factors for recurrence in patients with early stage node-negative breast cancer in this study.

METHOD

Retrospective data analysis was done on patient treatment records from 1988 to 2018. The patient's demographic, clinical, pathological, and therapeutic characteristics were noted. To evaluate survival analysis and predictors of recurrence, we employed Kaplan-Meier analysis with the log-rank test.

RESULTS

A total of 357 patients in all were enrolled in the research. At the time of diagnosis, the median age was 50 (with a range of 18-81). A total of 85.5% of patients had undergone a lumpectomy, while 14.5% had a mastectomy. 78.7% of patients had sentinel lymph node biopsy, and 21.3% had axillary lymph node dissection. In addition, the patients received adjuvant radiotherapy (88.7%), adjuvant endocrine therapy (82.1%), and adjuvant chemotherapy (48.5%). Recurrence of the tumor occurred in 31 (8.7%) patients (local recurrence 45.2% and metastatic disease 54.8%). Ten- and twenty-year recurrence-free survival rates were 92% and 77%. 19 (5.3%) patients had also developed contralateral breast cancer. Ten-year survival rates were 91.6%, and 20-year survival rates were 76.6%, respectively. Aged over 65 years (p = 0.004), necrosis (p = 0.002), mitosis (p = 0.003), and nuclear pleomorphism (p = 0.049) were found as statistically significant factors for recurrence in univariate analysis. In the ROC analysis, the largest size of the tumor (over 1.45 cm, p = 0.07) remained outside the statistical significance limit in terms of recurrence.

CONCLUSIONS

Thirty-year outcomes in individuals with early stage, node-negative breast cancer were shown in this study. We found that the recurrence ratios between 10 and 20 years were more frequent than the first 10 years during the follow-up. Despite the small number of patients who experienced a recurrence, we demonstrated that, in univariate analysis, being older than 65 and having some pathological characteristics (nuclear pleomorphism, mitosis, and necrosis) were statistically significant factors for disease recurrence.

Resemblance of the Recurrence Patterns in Primary Systemic, Primary Surgery and Secondary Oncoplastic Surgery

PURPOSE

Surgical interventions tend to have an effect on the generation of recurrences in tumor patients due to the anesthesia involved as well as tissue damage and subsequent inflammation. This can also be found in patients with breast cancer.

METHODS

In this multicenter study, we investigated data of 632 patients with breast cancer and the subsequent diagnosis of a recurrence. The patient data were acquired from 1 January 2006 to 31 December 2019 in eight different centers in Germany. The data sets were separated into those with primary surgery, primary systemic therapy with subsequent surgery, and reconstructive surgery. Three different starting points for observation were defined: the date of diagnosis, the date of first surgery, and the date of reconstructive surgery, if applicable. The observational period was divided into steps of six months and maxima of recurrences were compared. Furthermore, the variance was calculated using the difference of the distribution in percent.

RESULTS

The descriptive analysis showed no resemblance between the groups. The variance of the difference of the recurrence rates analysis using the surgical date as the starting point showed similarities in the age subgroup.

CONCLUSION

Our clinical analysis shows different metastatic behavior in different analysis and treatment regimes. These findings justify further investigations on a larger database. These results may possibly identify an improved follow-up setting depending on tumor stage, biology, treatment, and patient factors (i.e., age, …).

Suggestion for the omission of post-mastectomy chest wall radiation therapy in patients who underwent skin-sparing/nipple-sparing mastectomy

AIM

Both skin-sparing mastectomy (SSM) and nipple-sparing mastectomy (NSM) have been widely adopted. Although postmastectomy radiation therapy (PMRT) can improve clinical outcomes, it can worsen cosmesis following reconstruction. Therefore, identifying risk factors of ipsilateral breast tumor recurrence (IBTR) could help de-escalate PMRT after NSM/SSM in patients with pT1-2 disease.

METHODS

We retrospectively reviewed patients treated with SSM (N = 400) and NSM (N = 156) in patients with pT1-2N0-1 disease between 2009 and 2016. Seventy-four patients received PMRT with 50-50.4 Gy in 25-28 fractions. The Cox proportional hazards model was used to analyze the prognostic factors of IBTR.

RESULTS

With a median follow-up of 66.2 months, 17 IBTR events were observed, with 5-year IBTR-free rate of 97.2%. Although only one IBTR was observed after PMRT, there was no statistical difference in the 5-year IBTR-free rate (PMRT vs. no PMRT, 98.6% vs. 97.0%, p = 0.360). Multivariable analyses demonstrated that age ≤45 years and lymphovascular invasion (LVI) were adverse features of IBTR. The low-risk group (0 risk factor) showed a better 5-year IBTR-free rate than the high-risk group (≥1 risk factor) (100.0% vs. 95.8%, p = 0.003). In the high-risk group, PMRT slightly improved 5-year IBTR-free rate compared with no PMRT (98.6% vs. 95.2%, p = 0.166). In addition, PMRT increased 5-year cumulative incidence of reconstruction failure (10.0% vs. 2.8%, p = 0.001).

CONCLUSION

We identified risk factors (age and LVI) related to IBTR following upfront SSM/NSM with pT1-2 disease. As a hypothesis-generating study, de-escalation of PMRT by omitting chest wall irradiation in selective patients could improve reconstruction-related complications without compromising oncologic outcomes.

The effect of postmastectomy radiation therapy on high-risk patients with T1-2N0 breast cancer

BACKGROUND

The prognostic impact of postmastectomy radiation therapy (PMRT) on high-risk patients with T1-2N0 breast cancer is controversial. We aimed to investigate the effect of PMRT on high-risk patients with T1-2N0 breast cancer.

METHODS

A total of 3439 patients diagnosed with T1-2N0 breast cancer who received mastectomy between 2000 and 2016 in our institute were retrospectively analyzed. Leveraging the Fine and Gray competing risks regression in unirradiated patients, risk factors of locoregional recurrence (LRR) were identified. All patients were stratified into high-risk (3 or 4 risk factors) and low-risk (no more than 2 risk factors) groups. The prognostic effect of PMRT was estimated in two subgroups. This subgroup analysis was also performed in patients with T2N0 breast cancer.

RESULTS

The median follow-up was 89 months. The 5-year cumulative incidence of LRR was 2.2% in unirradiated patients. Tumor size, estrogen receptor (ER) status, histologic grade and lymphovascular invasion (LVI) were identified as independent risk factors of LRR. In the high-risk group, PMRT was correlated with a 8.3% risk reduction of 5-year LRR, 7.8% risk reduction of 5-year distant recurrence (DR), and 6.4% risk reduction of 5-year breast cancer mortality (BCM), whereas it was not correlated with LRR, DR, or BCM in low-risk group. In patients with T2N0 breast cancer, PMRT was associated with decreased LRR, DR and BCM in high-risk group, other than low-risk group.

CONCLUSIONS

PMRT presented heterogenous effect on patients with T1-2N0 breast cancer. Patients at high risk of LRR were more likely to benefit from PMRT.

Impact of clinical-pathological factors on locoregional recurrence in mastectomy patients with T1-2N1 breast cancer: who can omit adjuvant radiotherapy?

Purpose

Postmastectomy radiation therapy (PMRT) in T1–T2 tumors with 1–3 positive axillary lymph nodes (ALNs) is controversial. This study was to identify prognostic factors of locoregional control (LRC) following mastectomy with or without PMRT for patients with T1-2N1 breast cancer and to discuss the selection of patients who might omit PMRT.

Materials and methods

Between January 2006 and December 2012, the data of 1474 postmastectomy patients staged pT1-2N1 were analyzed. PMRT was applied in 663 patients. LRC and disease-free survival (DFS) were calculated using the Kaplan–Meier method. Cox regression model was applied in the univariate and multivariate analyses to recognize the recurrence risk factors.

Results

With the median follow-up duration of 93 months (range, 5–168 months), 78 patients (5.3%) failed to secure LRC and 220 patients (14.9%) experienced any recurrence. The 7.7-year LRC and DFS was 94.9% and 85.4% respectively in the entire cohort. PMRT significantly improved 7.7-year LRC from 93.4% to 96.6% (p = 0.005), but not the DFS (p = 0.335). Multivariate analysis revealed that PMRT was an independent prognostic factor of LRC (p < 0.001), meanwhile, age ≤ 40 years (p = 0.012), histological grade 3 (p = 0.004), 2–3 positive nodes (p < 0.001) and tumor size of 3–5 cm (p = 0.045) were significantly associated with decreased LRC. The 7.7-year LRC for patients with 0, 1, and 2–4 risk factors was 97.7% / 98.9% (p = 0.233), 95.3% / 98.0% (p = 0.092), and 80.3% / 94.8% (p < 0.001) in the non-PMRT and PMRT group, respectively.

Conclusions

In patients with T1-2N1 breast cancer, clinical-pathological factors including young age, histological grade 3, 2–3 positive nodes, and tumor size of 3–5 cm were identified to be predictors of a poorer LRC following mastectomy. Patients with 0–1 risk factor might consider the omission of PMRT.

Genomically Guided Breast Radiation Therapy: A Review of the Current Data and Future Directions

Purpose

To highlight the current evidence and the limitations in data to support a personalized approach in breast oncology radiation therapy management and define steps needed for clinical implementation.

Methods and Materials

A critical review of the current literature on the use of genomics in breast radiation therapy was undertaken by a group of breast radiation oncologists to discuss current data, future directions, and challenges.

Results

A summary of the existing data, ongoing clinical trials, and future directions is provided. The authors note many groups have developed radiation-specific genomic assays, which demonstrate promise in prediction of local control and benefit from radiation therapy; however, prospective validation of their utility is needed. Limitations continue to exist in our understanding of tumor biology and how it can be integrated into clinical practice.

Conclusions

Given the relative ubiquity of breast radiation therapy, the variety of dose and fractionation approaches, and the current data to support a personalized approach, it is our belief that the delivery of breast radiation therapy is uniquely poised for a genomically personalized radiation therapy approach. Prospective clinical trials implementing genomic signatures are needed at this time to advance the field.

Postmastectomy radiation therapy and survival outcome in older patients with T1-2N1 breast cancer

Background

The prognostic impact of postmastectomy radiation therapy (PMRT) on contemporary older patients with T1-2N1 breast cancer is unclear. We aimed to investigate the effect of PMRT in this setting.

Methods

Leveraging the Surveillance, Epidemiology, and End Results (SEER) program data from 2004 to 2015, 7052 patients aged 70 years or older with T1-2N1 breast cancer were identified for this propensity-matched analysis. Fine and Gray competing risks regression was conducted to explore the correlation between PMRT and breast cancer-specific survival, in subgroups defined by tumor size and positive lymph nodes.

Results

The median follow-up was 60.1 months (interquartile range, 28.0 to 87.0). Among propensity-matched patients, multivariate analysis identified an association between PMRT and decreased breast cancer mortality (BCM; HR 0.637; 95 % CI 0.436–0.931; P = 0.020) in patient subset with three positive nodes and tumors 2–5 cm in size, and this benefit was limited to patients with three positive nodes and tumors 2–5 cm in size who did not receive chemotherapy. In patient subsets who received chemotherapy, no association between PMRT and BCM was found.

Conclusion

PMRT was not associated with BCM in older patients with T1-2N1 breast cancer who received chemotherapy. The benefit of PMRT was limited to those with three positive nodes and tumors 2–5 cm in size who did not receive chemotherapy.

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46.0 % older patients with T1-2N1 breast cancer received postmastectomy radiation therapy (PMRT).

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28.8 % older patients with T1-2N1 breast cancer received chemotherapy.

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PMRT was beneficial for those with three positive nodes and tumors 2–5 cm in size who did not receive chemotherapy.

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No correlation between PMRT and BCM was found in patients who received chemotherapy.

Established and Validated Novel Nomogram for Predicting Prognosis of Post-Mastectomy pN0-1 Breast Cancer without Adjuvant Radiotherapy

Aim

To establish and validate a nomogram for predicting prognosis of breast cancer patients with pN0-1 who were treated with mastectomy and without adjuvant radiotherapy.

Material and Methods

The LASSO regression was performed to identify predictors of breast cancer-specific survival (BCSS), local regional recurrence (LRR) and distant metastasis (DM). Model performance was evaluated by the concordance index (C-index) and calibration plot.

Results

The 5-year BCSS, LRR and DM rates for the entire cohort were 98%, 2% and 4%, respectively. LASSO regression analysis found that pathological T stage, number of positive LN, grade and Ki-67 were significant predictors for both BCSS and DM-free survival, while number of resected LN and PR status were predictors for DM-free survival. In addition, number of positive LN was the only significant predictor for developing LRR. The C-indexes for the 5-year BCSS and DM nomograms were 0.81 and 0.78 in the training data set, 0.65 and 0.70 in the testing set and 0.72 and 0.69 in the external validation set, respectively.

Conclusion

Our prognostic nomograms accurately predict 5-year BCSS and DM-free survival in post-mastectomy breast cancer without adjuvant radiotherapy, which provides a useful tool to identify high-risk patients who could benefit from additional adjuvant therapy.

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.

Risk stratification for prediction of locoregional recurrence in patients with pathologic T1-2N0 breast cancer after mastectomy

Background

Previous studies have revealed that nearly 15–20% of selected high-risk T1–2N0 breast cancers developed LRR after mastectomy. This study is aim to indentify the risk factors of locoregional recurrence (LRR) in patients with pathologic T1–2N0 breast cancer after mastectomy in a real-world and distinguish individuals who warrant postmastectomy radiotherapy (PMRT).

Methods

Female patients treated from 1999 to 2014 in National Cancer Center of China were retrospectively reviewed. A competing risk model was developed to estimate the cumulative incidence of LRR with death treated as a competing event.

Results

A total of 4841 patients were eligible. All underwent mastectomy plus axillary nodes dissection or sentinel node biopsy without PMRT. With a median follow-up of 56.4 months (range, 1–222 months), the 5-year LRR rate was 3.9%.Besides treatment era, age ≤ 40 years old (p < 0.001, hazard ratio [HR] = 2.262), tumor located in inner quadrant (p < 0.001, HR = 2.236), T2 stage (p = 0.020, HR = 1.419), and negative expressions of estrogen receptor (ER) and progesterone receptor (PR) (p = 0.032, HR = 1.485), were patients-related independent risk factors for LRR. The 5-year LRR rates were 1.7, 3.5, and 15.0% for patients with zero, 1–2, and 3–4 risk factors (p < 0.001).

Conclusions

Risk Stratification based on age, T stage, ER/PR status and tumor location can stratify patients with pT1–2 N0 breast cancer into subgroups with different risk of LRR. PMRT might be suggested for patients with 3–4 risk factors.

Locoregional recurrence patterns in women with breast cancer who have not undergone post-mastectomy radiotherapy

Background

To analyze the patterns of locoregional recurrence in breast cancer patients after mastectomy.

Methods

The retrospective study included 7073 women with breast cancer without post-mastectomy radiotherapy: 4604 (65.1%) had pT1–2 N0 disease (low risk); 2042 (28.9%), pT1–2 N1 (intermediate risk); and 427 (6.0%), pT3–4 and/or pN2–3, or pT1–2 N1 after neoadjuvant chemotherapy (high risk). The distribution of cumulative locoregional recurrence was analyzed. The local recurrence and regional recurrence rates were estimated by the Kaplan-Meier method, and differences were compared with the log-rank test. Multivariate analysis was performed using Cox logistic regression analysis.

Results

In the median follow-up of 63.0 months, 469 patients had locoregional recurrence: chest wall recurrence in 238 (50.7%) cases, supraclavicular/infraclavicular nodes in 236 (50.3%) cases, axilla in 92 (19.6%), and internal mammary nodes in 50 (10.7%) cases. The 5-year local recurrence and regional recurrence rates were 2.5 and 4.4%, respectively. Subgroup analysis of the three risk groups and five molecular subtypes (luminal A, luminal B-Her2 negative, luminal B-Her2 positive, Her2-enriched, and triple negative) also showed that the chest wall and supraclavicular/infraclavicular nodes were the most common recurrence sites. Age, tumor location, T stage, N stage, and hormone receptor status were independent prognostic factors for both local recurrence and regional recurrence (p < 0.05).

Conclusions

The chest wall and supraclavicular/infraclavicular nodes are common sites of locoregional recurrence in breast cancer, irrespective of disease stage or molecular subtype, and the prognostic factors for local recurrence and regional recurrence are similar. Therefore, chest wall and supraclavicular/infraclavicular nodes irradiation should always be considered in post-mastectomy radiotherapy.

Analysis of Breast Cancer Patients with T1-2 Tumors and 1-3 Positive Lymph Nodes Treated with or without Postmastectomy Radiation Therapy

The use of postmastectomy radiation therapy (PMRT) has been recommended for patients with 4 or more positive lymph nodes, however, its role in patients with 1-3 positive lymph nodes remains unclear. The purpose of this study is to evaluate oncological outcomes for breast cancer patients with T1-2 tumors and 1-3 positive lymph nodes after undergoing PMRT. We performed a single-institution retrospective investigation that evaluated the association between PMRT and outcomes in breast cancer patients with T1-2 tumors and 1-3 positive lymph nodes, who underwent mastectomy from 2004 to 2015. Multivariable Cox proportional hazards regression was used to evaluate the association of PMRT with disease-free survival and overall survival. A total of 379 patients met inclusion criteria, of which 204 (54%) received PMRT while 175 (46%) did not receive PMRT following mastectomy and were followed over a median of 5.2 years (25^th–75^th percentile: 2.8–8.4 years). Recurrence was similar in patients receiving PMRT compared to those that did not: locoregional (0 vs 3, P = 0.061), distant (9 vs 3, P = 0.135) and any recurrence (11 vs 7, P = 0.525). After adjustment for potential confounding variables, PMRT was not associated with a statistically significant difference in disease-free survival (HR: 0.93; 95% CI: 0.48, 1.79) or overall survival (HR: 0.91; 95% CI: 0.45, 1.85). PMRT was not associated with improved oncological outcomes in patients with T1-2 breast cancer and 1-3 positive lymph nodes at our institution.

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.

Postmastectomy radiation therapy in early breast cancer: Utility or futility?

Postmastectomy radiation therapy (PMRT) has been shown to reduce the risk of locoregional recurrence (LRR), in patients with locally advanced breast cancer who are considered of high-risk because of large tumors (>5 cm) or presence of axillary lymph-node involvement, as well as to reduce breast cancer mortality. However, controversy still remains with respect to indication of PMRT in case of early-stages invasive tumors. This review aims to analyze the impact that PMRT has on final results in women with breast tumors in different scenarios that would otherwise be considered as early breast cancer, such as extensive DCIS, tumors without axillary lymph-node involvement or with minimal microscopic nodal-involvement. The existence of risk factors including young age, premenopausal status, and presence of lymphovascular invasion (LVI), high grade or tumor size >2 cm has been associated with an increased risk of LRR in these patients at early-stages and advises to consider PMRT in selected cases.

The Value of Prognostic Nutritional Index (PNI) in Predicting Survival and Guiding Radiotherapy of Patients With T1-2N1 Breast Cancer

Background: To investigate the significance of the prognostic nutrition index (PNI) as a predictor of survival and guide for treating T1-2N1 breast cancer.

Methods: Patients with T1-2N1 breast cancer (N = 380) who underwent a mastectomy at our center were studied. PNI was calculated as 10 × serum albumin (g/dl) + 0.005 × total lymphocyte count (per mm³). The cutoff for the PNI was calculated using the time-dependent receiver operating characteristic (ROC) curve analysis by overall survival (OS) prediction. The associations between the PNI and the clinicopathologic characteristics were analyzed using Pearson's χ² test. Survival curves were calculated using the Kaplan–Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazards model.

Results: Subgroup analyses of patients with low PNI value (≤52.0) and high PNI value (>52.0) showed that a high PNI was significantly associated with HER2 status, the neutrophil–lymphocyte ratio (NLR), the monocyte–lymphocyte ratio (MLR), and KI 67 status. The OS of patients with a high PNI was significantly better than that of patients with a low PNI. We then conducted subgroup analyses based on PNI and radiotherapy. Among patients who received radiotherapy, the OS of those with a high PNI was significantly better than that of patients with a low PNI. Among patients with a high PNI, the OS of those who received radiotherapy was better than that of the patients who did not receive radiotherapy. However, among the patients with a low PNI, the OS of those who received radiation was worse than that of patients who did not receive radiotherapy. The Kaplan–Meier survival analysis and the multivariate analysis of patients with T1-2N1 breast cancer who received radiotherapy showed PNI independently predicted OS.

Conclusions: The preoperative PNI may be a reliable predictor of OS of patients with operable T1-2N1 breast cancer, with the capacity to provide a personalized prognosis and facilitate the development of clinical treatment strategies. However, radiotherapy did not achieve satisfactory outcomes in patients with PNI ≤52.0; thus, further studies on treatment optimization are needed.

Can a subgroup at high risk for LRR be identified from T1-2 breast cancer with negative lymph nodes after mastectomy? A meta-analysis

Purpose: To identify a subgroup at high risk for loco-regional recurrence (LRR) from T1-2 breast cancer with negative lymph nodes (N0) after mastectomy by using a meta-analysis.Methods and materials: Published studies on the relationship between clinical features and LRR of breast cancer were identified from public databases, including PubMed, EMBASE, and the Cochrane Library. High-risk features for LRR in this patient population were defined based on the pooled results of meta-analysis.Results: For the meta-analysis, a total of 11244 breast cancers with pT1-2N0 after mastectomy from 20 publications were included for analysis. The pooled results indicated that age (hazard ratio (HR) 1.77, P=0.001), lymphovascular invasion (LVI) (HR 2.23, P<0.001), histologic grade (HR 1.66, P<0.001), HER2 status (HR 1.65, P=0.027), menopausal status (HR 1.36, P=0.015), and surgical margins (HR 2.56, P=0.014) were associated with a significantly increased risk of developing LRR in this patient population group, but not for tumor size (HR 1.32, P=0.23), systematic therapy (HR 1.67, P=0.20), and hormonal receptor status (HR 1.04, P=0.73).Conclusion: In the current study, patients with young age, positive LVI, high histologic grade, HER-2 positive, premenopausal, and positive surgical margins have an increased risk of developing LRR. Further prospective trials are needed to clearly define the role of adjuvant postmastectomy radiotherapy in T1-2N0 breast cancer at high risk of developing LRR.

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.

Overview of Breast Cancer Therapy

Breast cancer treatment is multidisciplinary. Most women with early stage breast cancer are candidates for breast-conserving surgery with radiotherapy or mastectomy. The risk of local recurrence and the chance of survival does not differ with these approaches. Sentinel node biopsy is used for axillary staging, and individualized approaches are minimizing the need for axillary dissection in women with positive sentinel nodes. Adjuvant systemic therapy is used in most women based on proven survival benefit, and molecular profiling to individualize treatment based on risk is now a clinical reality for patients with hormone receptor-positive cancers.

Molecular determinants of post-mastectomy breast cancer recurrence

Breast cancer (BC) adjuvant therapy after mastectomy in the setting of 1-3 positive lymph nodes has been controversial. This retrospective Translational Breast Cancer Research Consortium study evaluated molecular aberrations in primary cancers associated with locoregional recurrence (LRR) or distant metastasis (DM) compared to non-recurrent controls. We identified 115 HER2 negative, therapy naïve, T 1-3 and N 0-1 BC patients treated with mastectomy but no post-mastectomy radiotherapy. This included 32 LRR, 34 DM, and 49 controls. RNAseq was performed on primary tumors in 110 patients; with no difference in RNA profiles between patients with LRR, DM, or controls. DNA analysis on 57 primary tumors (17 LRR, 15 DM, and 25 controls) identified significantly more NF1 mutations and mitogen-activated protein kinase (MAPK) pathway gene mutations in patients with LRR (24%, 47%) and DM (27%, 40%) compared to controls (0%, 0%; p < 0.0001 and p = 0.0070, respectively). Three patients had matched primary vs. LRR samples, one patient had a gain of a NF1 mutation in the LRR. There was no significant difference between the groups for PTEN loss or cleaved caspase 3 expression. The mean percentage Ki 67 labeling index was higher in patients with LRR (29.2%) and DM (26%) vs. controls (14%, p = 0.0045). In summary, mutations in the MAPK pathway, specifically NF1, were associated with both LRR and DM, suggesting that alterations in MAPK signaling are associated with a more aggressive tumor phenotype. Validation of these associations in tissues from randomized trials may support targeted therapy to reduce breast cancer recurrence.

Clinical decision making in postmastectomy radiotherapy in node negative breast cancer

For decades, postmastectomy radiotherapy (PMRT) has been recommended for node positive [N(+)] breast cancer patients; nevertheless, the beneficial effect of PMRT for treatment of node negative [N(−)] disease remains under discussion. Nowadays, the biology of breast cancer and the risk factors (RFs) for locoregional failure (LRF) must be included in the decision on whether or not to carry out PMRT. For these reasons, the present review aims to evaluate the rationale use of PMRT in N(−) patients and discuss which subgroups may further benefit from the treatment in present times where the decision must be personalised, according to the RFs of locoregional recurrence (LRR). To perform the analysis, we ponder that LRR of over 10% should be considered unacceptable due to the fact that LRRs generate great morbidity in patients. For this purpose, we consider that routine RT in these patients is not recommended, although there are subgroups of patients with high LRR, in which PMRT could be beneficial.

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.

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.

Trends and variations in postmastectomy radiation therapy for breast cancer in patients with 1 to 3 positive lymph nodes: A National Cancer Data Base analysis

BACKGROUND

High-level evidence is lacking to guide treatment decisions about postmastectomy radiation therapy (PMRT) in patients who have breast cancer with 1 to 3 positive lymph nodes who receive contemporary systemic therapies, leading to potential variations in PMRT delivery. The objective of this study was to examine nationwide trends in PMRT use in this group.

METHODS

The National Cancer Data Base (NCDB) was used to identify 93,372 women who had T1-T2N1 breast cancer diagnosed between 2003 and 2012. Patients who received neoadjuvant chemotherapy or radiation therapy (RT) and those who had bilateral breast cancers were excluded. Time trends were evaluated using the Cochrane-Armitage test and correlated the receipt of PMRT with various patient demographic, facility, clinicopathologic, and treatment variables using multivariable logistic regression. A second analysis was performed for patients who were diagnosed during 2010 and included radiation oncologist density as an additional covariate. P values < .0001 were considered statistically significant.

RESULTS

Overall, 22.5% of the study population received PMRT, representing an increase from 19.1% in 2003 to 30.3% in 2012. Factors associated with greater PMRT use included younger age, lower Charlson-Deyo comorbidity scores, shorter distance to the treating facility, treatment at a comprehensive cancer program, facility location in the New England Census division, and higher density of radiation oncologists. Increased PMRT use was associated with later year of diagnosis, receipt of chemotherapy, receipt of hormone therapy, higher grade disease, larger tumor size, greater numbers of positive lymph nodes, positive margins, and absence of immediate breast reconstruction (all P < .0001).

CONCLUSIONS

The receipt of PMRT by patients with breast cancer who have 1 to 3 positive lymph nodes has increased over time, with wide variability in practice patterns in the United States. Cancer 2018;124:482-90. © 2017 American Cancer Society.

Radiation Therapy and Immediate Breast Reconstruction: Novel Approaches and Evidence Base for Radiation Effects on the Reconstructed Breast

Patients who undergo breast reconstruction experience higher complication rates if they have had a history of radiotherapy. However, implant-based reconstruction confers significantly higher complication and reconstruction failure rates compared with autologous reconstruction. This article analyses the factors that contribute to the complications of the different breast reconstruction modalities and the strategies described to mitigate these problems.

Axillary Micrometastases and Isolated Tumor Cells Are Not an Indication for Post-mastectomy Radiotherapy in Stage 1 and 2 Breast Cancer

BACKGROUND

Randomized trials demonstrate equivalent locoregional control with sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND) for T1-2 micrometastatic breast cancer, but include few mastectomy patients. Consensus is lacking on indications for post-mastectomy radiotherapy (PMRT) in this population. Herein, we evaluate locoregional recurrence (LRR) in an unselected, modern cohort of T1-2 breast cancer patients with micrometastases or isolated tumor cells (ITCs; N0i+/N1mi) having a mastectomy.

METHODS

We identified patients with T1-2N0i+/N1mi breast cancer treated with mastectomy from January 2006 to December 2011. Recurrent, bilateral, and neoadjuvant cases were excluded. The primary outcome of interest was LRR.

RESULTS

Overall, 352 patients [211 (60%) with ITCs and 141 (40%) with micrometastases] were identified. 162 (46%) patients had SLNB alone and one node was positive in 295 (84%) cases; 31 (9%) patients had PMRT and 95% had systemic therapy. At a median 6 years of follow-up, the overall crude LRR rate was 2.8% (n = 9), with no axillary recurrences, and the crude LRR rate was 3.9% among those who had SNB alone. Those with LRR had a median age of 55 years, median tumor size of 1.7 cm, and ductal histology; the majority were high-grade (89%) and estrogen receptor positive (78%), with one positive node (89%). There was no association between LRR and receipt of PMRT (p = 0.4), SLNB versus ALND (p = 0.2), or number of positive nodes (p = 0.7) using the log-rank test.

CONCLUSIONS

LRR was infrequent among T1-2N0i+/N1mi patients treated with mastectomy without PMRT, with no axillary failures, suggesting that PMRT or nodal radiotherapy are not routinely indicated in this population.

Improved Locoregional Control in a Contemporary Cohort of Nonmetastatic Inflammatory Breast Cancer Patients Undergoing Surgery

BACKGROUND

Inflammatory breast cancer (IBC) is an aggressive form of breast cancer characterized by rapid progression and early metastatic dissemination. The purpose of this study was to assess contemporary rates of local regional recurrence (LRR) in the era of trimodality therapy for nonmetastatic IBC and identify risk factors leading to local failure.

METHODS

A total of 114 patients with nonmetastatic IBC receiving trimodality therapy (neoadjuvant chemotherapy, surgery, and radiation therapy) were identified from a prospectively collected database from 2007 to 2015 and outcomes analyzed.

RESULTS

Median age at diagnosis was 52 years, and the median follow-up was 3.6 years. Sixty-three (55%) patients presented with N2 IBC, and 52 patients (45%) presented with N3 IBC. Local regional recurrence was observed during follow-up for four patients; 25 died, and 85 were censored at last follow-up. Surgical margins were negative in 99% of patients (n = 113). The 2-year probability of LRR was 3.19% (95% confidence interval 1.03-9.90%). Five-year overall survival for this cohort was 69.14%. Improvement in disease-free survival was seen among patients with HER2+ subtype, clinical stage IIIB, complete or partial radiologic response to neoadjuvant therapy, pathologic complete response, and lower nodal burden on presentation.

CONCLUSIONS

Locoregional recurrences were rare at a median of 3.6 years follow-up in a contemporary cohort of IBC patients treated with trimodality therapy. Although longer follow-up is needed, aggressive surgical resection to negative margins in the frame of trimodality therapy with curative intent can lead to LRR rates that mirror non-IBC rates.

Establishment of a risk scoring system for predicting locoregional recurrence in T1 to T2 node-negative breast cancer patients treated with mastectomy: Implications for postoperative radiotherapy

To establish a risk scoring system for predicting locoregional recurrence (LRR) and explore the potential value of radiotherapy in T1 to T2 node-negative breast cancer patients treated with mastectomy. From January 2001 to February 2008, a total of 353 node-negative T1 to T2 breast cancer cases treated with mastectomy without adjuvant radiotherapy were retrospectively analyzed. Preliminary screening of the prognostic factors was accomplished by Kaplan-Meier univariate analysis, and survival curves between different groups were compared by log-rank test. Risk factors were determined using Cox proportional hazards model. A categorical risk scoring system was generated according to the Cox model, weighing the relative importance of each risk variable. Median follow-up was 115.7 months (range, 1.2-238.4 months). The overall 5-year locoregional recurrence-free survival (LRFS) was 89.8% (95% confidence interval [CI] = 86.7%-92.9%). Chest wall (53.8%) was found to be the most common site of LRR, followed by supraclavicular nodes (48.7%). Age ≤40 years, primary tumor size ≥4.5 cm and number of nodes resected ≤10 were found to be independent factors for poor prognosis of LRR. Two risk stratifications based on the scoring system were subsequently obtained. The 5-year LRFS was 91.6% (95% CI = 88.5%-94.7%) with low risk (score <2) and 75.7% (95% CI = 61.8%-89.6%) with high risk (score ≥2), respectively (χ = 7.544, P = .006). In addition, significant differences in overall survival (P = .045) and disease-free survival (P = .019) were presented between them. Patients with T1-2N0M0 breast cancer achieved favorable prognosis in general. Those with risk factors, including age ≤40 years, primary tumor size ≥4.5 cm and number of nodes resected ≤10, were at higher risk of LRR. The established scoring system could help to distinguish the subgroups that might potentially benefit from postoperative radiotherapy.

Are there patients with T1 to T2, lymph node-negative breast cancer who are "high-risk" for locoregional disease recurrence?

BACKGROUND

Indications for postmastectomy radiotherapy (PMRT) in patients with T1 to T2, lymph node-negative (N0) breast cancer with "high-risk" features are controversial. The European Organization for Research and Treatment of Cancer (EORTC) 22922 and National Cancer Institute of Canada Clinical Trials Group MA20 trials reporting improved 10-year disease-free survival with lymph node irradiation included patients with high-risk N0 disease, but, to the authors' knowledge, benefits in patients receiving modern systemic therapy are uncertain.

METHODS

The authors retrospectively identified patients with T1 to T2N0 disease who were treated with mastectomy from January 2006 through December 2011. High-risk features included age <40 years, multifocality/multicentricity, lymphovascular invasion, medial/central tumor location, and high nuclear grade.

RESULTS

Among 672 eligible patients, only 15 received PMRT and were excluded. Of the remaining 657 patients, 187 (28%) had 1 high-risk feature and 449 patients (68%) had ≥ 2 high-risk features. A total of 36 patients with unknown tumor grade were excluded from risk analysis. Approximately 98% of patients underwent sentinel lymph node biopsy alone and 86% received adjuvant systemic therapy. At a median of 5.6 years of follow-up, the locoregional disease recurrence (LRR) rate was 4.7% (31 patients). Increasing tumor size was found to be associated with LRR (hazard ratio, 1.70; P = .006), whereas other high-risk features were not (all P > .05). Receipt of systemic therapy decreased the LRR rate (hazard ratio, 0.40; P = .03). Although crude LRR rates increased from 3.8% to 9.4% with 1 versus ≥ 4 high-risk features, the number of risk factors was not found to be significantly associated with LRR (P = .54).

CONCLUSIONS

In the current study, a low crude LRR rate (4.7%) was observed in a large unselected cohort of patients with T1 to T2N0 breast cancer with high-risk features who were treated with mastectomy and systemic therapy without PMRT. Although increasing tumor size and the omission of systemic therapy were found to be predictive, other features did not confer a higher LRR risk either independently or together, and do not by themselves mandate the use of PMRT in this patient population. Cancer 2017;123:2626-33. © 2017 American Cancer Society.

Possible benefits from post-mastectomy radiotherapy in node-negative breast cancer patients: a multicenter analysis in Korea (KROG 14-22)

PURPOSE

This study was performed to identify a subset of patients who may benefit from post-mastectomy radiotherapy (PMRT) among node-negative breast cancer patients.

MATERIALS AND METHODS

We retrospectively reviewed 1,828 patients with pT1-2N0 breast cancer, treated with mastectomy without PMRT from 2005 to 2010 at 10 institutions. Univariate and multivariate analyses for locoregional recurrence (LRR) and any first recurrence (AFR) were performed according to clinicopathologic factors and biologic subtypes.

RESULTS

During a median follow-up period of 5.9 years (range: 0.7-10.4 years), 98 patients developed AFR (39 isolated LRR, 13 LRR with synchronous distant metastasis, and 46 isolated distant metastasis), and 52 patients developed LRR. The 7-year LRR and AFR rates were 3.8% and 6.7%, respectively. Multivariate analysis revealed that age of ≤ 40 years (p<0.001) and T2 stage (p=0.013) were independent risk factors for LRR. The 7-year LRR rates were 2.5% with no risk factors, 4.5% with one risk factor, and 12.4% with two risk factors. Multivariate analysis for AFR revealed that age of ≤ 40 years (p<0.001), T2 stage (p<0.001), and triple-negative biological subtype (p=0.045) were independent risk factors for AFR. The 7-year AFR rates were 3.9% with no risk factors, 8.4% with one risk factor, and 15.7% with two to three risk factors.

CONCLUSIONS

Mastectomy without PMRT is a sufficient local treatment for pT1-2N0M0 breast cancer. Nevertheless, PMRT might be considered for patients with two or three risk factors, among those of young age, with T2 tumors, and with the triple-negative biological subtype based on LRR and AFR.

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.

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.

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.

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.

Identification of Risk Factors for Locoregional Recurrence in Breast Cancer Patients with Nodal Stage N0 and N1: Who Could Benefit from Post-Mastectomy Radiotherapy?

INTRODUCTION

The locoregional recurrence (LRR) rate was reported as high as approximately 20% in stage I-II breast cancer following mastectomy. To investigate the risk factors for LRR in pT1-2N0-1 breast cancer patients treated with mastectomy but not radiation, and to define a subgroup of patients at high risk of LRR who may benefit from postmastectomy radiotherapy (PMRT).

METHODS AND MATERIALS

In total, 390 patients with pT1-2N0M0 (n = 307) and pT1-2N1M0 (n = 83) breast cancer who underwent total mastectomy without adjuvant radiotherapy from 2002 to 2011 were enrolled in the study.

RESULTS

After a median follow-up period of 5.6 years (range, 0.6-11.3 years), 21 patients had 18 systemic relapses and 12 LRRs including six in the chest wall and eight in the regional nodal area. The 5-year LRR-free survival (LRRFS) rates were 97.0% in pN0, 98.8% in pN1, and 97.4% in all patients. Multivariate analysis revealed that age < 50 years (Hazard Ratio, 11.4; p = 0.01) and no adjuvant chemotherapy (Hazard Ratio, 10.2; p = 0.04) were independent risk factors for LRR in pN0 patients. Using these factors, the 5-year LRRFS rates were 100% without any risk factors, 96.4% with one risk factor, and 86.7% with two risk factors. In pN1 patients, multivariate analysis revealed that having a hormone receptor negative tumor (Hazard Ratio, 18.3; p = 0.03) was the only independent risk factor for LRR. The 5-year LRRFS rates were 100.0% for luminal type, and 92.3% for non-luminal type cancer.

CONCLUSION

Patients with pT1-2N0-1 breast cancer who underwent total mastectomy without PMRT could be stratified by nodal stage and risk factors for LRR. PMRT may have of value for node negative patients aged less than 50 years and who are not treated with adjuvant chemotherapy, and for non-luminal type patients with one to three positive nodes.

Postmastectomy radiotherapy benefit in Chinese breast cancer patients with T1-T2 tumor and 1-3 positive axillary lymph nodes by molecular subtypes: an analysis of 1369 cases

The aim of this study was to examine the association between molecular subtype (MST) and prognosis and research the postmastectomy radiotherapy (PMRT) effect in T1-T2 tumors with 1-3 positive axillary lymph nodes (ALNs). This retrospective study studied breast cancer patients with T1-T2 tumors and 1-3 positive ALNs according to MST: Luminal A, Luminal B, human epidermal growth factor receptor-2 (Her-2) positive, and Triple negative. The impact of adjuvant PMRT in T1-T2 tumors with 1-3 positive ALNs was also assessed. This study included 1369 patients: 33.0 % Luminal A, 42.9 % Luminal B, 11.9 % Her-2 positive, and 12.2 % Triple negative. On univariate and multivariate analyses, MST was associated with locoregional relapse (LRR). Kaplan-Meier analysis showed that PMRT significantly decreased LRR risk (p = 0.017) and distant metastasis (DM) risk (p < 0.0001). In subgroup analysis, PMRT showed significant benefits of improvement in LRR in patients with younger age, positive lymphovascular invasion (LVI), and ratio of positive lymph nodes (LNs) >25 %. Moreover, the nomogram could more accurately predict LRR (c-index 0.75) in T1-2N1 breast cancer patients. MST associated with patient outcomes in breast cancer patients with T1-T2 tumors and 1-3 positive ALN. It makes sense to offer PMRT for patients aged<40 years old, LVI, 2 and 3 positive lymph nodes, and ratio of positive LNs >25 %.

Whose Disease Will Recur After Mastectomy for Early Stage, Node-Negative Breast Cancer? A Systematic Review

Effective local control is associated with improved overall survival, particularly for women with early-stage cancers. No other local therapy is typically offered to women with T1-2 N0 breast cancer after mastectomy, although in select women the 5-year local recurrence rate can be as high as 20%. Therefore, accurately predicting the women who are at highest risk for recurrence after mastectomy will identify those who might benefit from more aggressive adjuvant treatment. A systematic search was conducted identifying risk factors associated with locoregional recurrence, including age, menopausal status, receptor status, lymphovascular invasion (LVI), margin status, use of systemic therapy, size, grade, and genomic classifer score. Although associations varied among studies, the risk factors most consistently identified were age ≤ 40 years, LVI, positive/close margin, and larger tumor size. In women with multiple high risk factors, risk of local recurrence was as high as 20% at 10 years. Additional multicenter studies are needed to investigate risk factors for locoregional recurrence after mastectomy without radiotherapy in T1-2N0 breast cancer. Consideration of additional adjuvant local therapy might be warranted in a subset of women at high risk of local recurrence.

Metastatic Tumor Volume and Extranodal Tumor Extension: Clinical Significance in Patients With Stage II Breast Cancer

CONTEXT

Lymph node status and the number of lymph node (LN) positive for cancer cells are the most important prognostic factors in breast cancer. Extranodal tumor extension (ENTE) has been used as a histopathologic feature to classify patients into high risk versus low risk for local recurrence. However, in the current era of early detection and systemic therapy, the prognostic significance of ENTE is not as well defined in patients with 1 to 3 LNs positive for cancer.

OBJECTIVE

To determine whether the amount of tumor burden in an axillary dissection or the presence of ENTE provides any additional information regarding patient outcome in patents with 1 to 3 positive LN results.

DESIGN

Clinical and pathologic factors were identified for 456 patients with breast cancer at the University of Texas MD Anderson Cancer Center, Houston, who had pT1 tumors and 1 to 3 LNs positive for cancer and were treated by mastectomy, with or without postmastectomy radiotherapy, between 1978 and 2007.

RESULTS

Of the 456 patients, 257 (56.4%), 141 (31.6%), and 58 (12.7%) patients had 1, 2, or 3 positive LN results, respectively. Extranodal tumor extension was present in 99 patients (21.7%) and was absent in the remaining 357 cases (78.3%). Seventy-six patients (16.7%) received radiation therapy. Patients had both worse overall survival time and disease-free survival when ENTE was present, regardless of the amount, as long as the treatment era was not included in the multivariate analysis (pre-2000 versus post-2000). However, ENTE was no longer significant on multivariate analysis when the year of treatment was taken into account.

CONCLUSIONS

The number of positive LNs remains an important predictor of survival in patients with 1 to 3 positive LN results, but the prognostic significance of ENTE in this cohort of patients has diminished over time.

Risk factors for locoregional recurrence after mastectomy in stage T1 N0 breast cancer

OBJECTIVES

Postmastectomy radiotherapy (PMRT) is proven to decrease locoregional recurrence (LRR) in locally advanced breast cancer. However, there is little data regarding PMRT in early stage disease. This study examines risk factors for LRR in patients who underwent mastectomy for T1 N0 breast cancer, with the aim of identifying a subgroup who may potentially benefit from PMRT.

METHODS

From 1994 to 2004, there were 1259 pathologic stage T1 N0 breast cancers treated with mastectomy and no radiation within the Kaiser Permanente Southern California medical system. Kaplan-Meier survival curves for LRR were compared using the log-rank test, and multivariate analysis was done using Cox proportional hazard ratios to identify risk factors for LRR.

RESULTS

Median follow-up was 8.15 years. The 10-year Kaplan-Meier LRR rate was 3.2% (95% confidence interval [CI], 2%-4.3%). The median time to LRR was 2.5 years after mastectomy, and the most common site was chest wall (68%). Grade 3 (hazard ratio 3.97; 95% CI, 1.94-8.14; P = 0.0002) and margins ≤ 3 mm (hazard ratio 2.97; 95% CI, 1.21-7.29; P = 0.02) were significantly associated with LRR on multivariate analysis. The 10-year Kaplan-Meier rate of LRR for the 1230 patients with neither or one factor was 2.7% (95% CI, 1.6%-3.8%), compared with a LRR rate of 25% (95% CI, 2.2%-42.7%) among the 29 patients with both high grade and margins ≤ 3 mm (P < 0.0001).

CONCLUSIONS

After mastectomy for pT1 N0 breast cancer, there is a small subgroup of patients with grade 3 disease and a close or positive margin (≤ 3 mm) who have an increased risk of LRR. These patients may benefit from the administration of PMRT.

Postmastectomy radiotherapy: indications and implications

BACKGROUND

Although breast conservation surgery, when combined with radiotherapy, has been shown to provide excellent locoregional control for breast cancer, approximately one third of women with breast cancer require mastectomy. Many of these women are offered immediate reconstruction. Postmastectomy radiotherapy (PMRT) is indicated in some cases, but is associated with side-effects, including its impact on the reconstructed breast.

OBJECTIVE

To review the pertinent issues surrounding PMRT, including patient selection for radiotherapy and the effect of radiotherapy on reconstructive decisions.

METHODS

A literature review was performed using the Medline database.

CONCLUSIONS

PMRT is indicated in patients who are deemed to have a high risk of loco-regional recurrence. Although PMRT is strongly recommended for patients with four or more positive lymphnodes, other indications for PMRT remain controversial. Immediate reconstruction post mastectomy has been shown to have favorable outcomes. However, PMRT may increase the need for revision surgery post immediate reconstruction. There are few randomized trials looking at these key issues, and the evidence is largely derived from observational retrospective studies. Patients should be carefully counseled before a decision is made to proceed with immediate reconstruction, where there is a high chance that PMRT may be indicated.