Post-mastectomy radiotherapy in pT3N0M0 breast cancer: is it needed?

Post-mastectomy reirradiation for ipsilateral T3N0M0 breast tumor relapse: a population-based study

INTRODUCTION

Post-mastectomy radiotherapy is commonly recommended for T3N0M0 breast cancer, particularly in the presence of adverse prognostic factors. However, for T3N0M0 ipsilateral recurrences following breast-conserving surgery and adjuvant radiotherapy, the situation is distinct. Recurrence alone signifies a negative prognostic factor. Moreover, tumor relapses within previously irradiated areas exhibit enhanced radioresistance, and reirradiation of the chest wall carries an escalated risk of radiation-induced toxicity. This study aimed to assess the impact of post-mastectomy reirradiation (PM-reRT) on patient outcomes in cases of ipsilateral T3N0M0 breast tumor recurrence, using data from the SEER database.

MATERIALS AND METHODS

We identified all patients who underwent treatment for primary non-metastatic breast cancer with breast-conserving surgery followed by adjuvant radiotherapy in the SEER database; among them, those who later experienced a localized T3N0M0 breast tumor recurrence and underwent total mastectomy were included. The study's goal was to compare overall survival (OS) and cancer-specific survival (CSS) between patients who underwent only mastectomy versus those who had mastectomy followed by adjuvant PM-reRT for their ipsilateral T3N0M0 breast tumor relapse.

RESULTS

From 2000 to 2020, the SEER database recorded 44 patients with an ipsilateral T3N0M0 breast tumor recurrence after initial conservative treatment, managed with total mastectomy. No statistically significant differences in OS or CSS were observed between patients undergoing mastectomy (MT) alone versus those receiving MT combined with PM-reRT (p = 0.68 and p = 0.86, respectively). Five-year OS rates for the MT and MT + PM-reRT cohorts were 49.5% [95% CI: 29.9-81.8] and 41.7% [10.0-100.0], respectively, while 5‑year CSS rates were 51.6% [12.0-99.5] and 58.3% [15.2-100.0], respectively.

CONCLUSION

For patients undergoing total mastectomy after an ipsilateral T3N0M0 breast tumor recurrence, subsequent to initial breast cancer treatment involving breast-conserving surgery and adjuvant radiotherapy, chest wall reirradiation does not enhance survival outcomes. As such, it should not be routinely performed.

Nomogram-Based Risk Stratification to Identify Patients with T3N0M0 Breast Cancer with Survival Benefit from Postmastectomy Radiotherapy

BACKGROUND

The survival benefit of postmastectomy radiotherapy (PMRT) for patients with T3N0M0 breast cancer remains controversial. This study aimed to identify patients with a survival benefit from PMRT by developing a novel risk stratification model.

PATIENTS AND METHODS

The study recruited 2062 patients with pT3N0M0 breast cancer from the Surveillance, Epidemiology, and End Results (SEER) database who underwent mastectomy between 2010 and 2019. Overall survival (OS) and breast-cancer-specific survival (BCSS) prognostic nomograms based on multivariate Cox regression were constructed to quantify the survival risk and classify patients into low- and high-risk groups. Subgroup analyses were undertaken to assess the role of PMRT according to age and risk stratification.

RESULTS

In the overall cohort, PMRT was beneficial in improving OS in patients with pT3N0 breast cancer (5-year OS, non-PMRT versus PMRT: 76.6% vs. 84.2%, P < 0.001), while the benefit on BCSS was not significant (P = 0.084). On the basis of the risk stratification nomogram, in the high-risk group, PMRT improved OS in young patients by 10.1%, OS in elderly patients by 12.4%, and BCSS by 10.2% (P < 0.05), but the use of PMRT in the low-risk group did not improve OS and BCSS in all patients (P > 0.05).

CONCLUSIONS

We presented a new method for quantifying risk using the nomogram to identify patients with high risk of pT3N0M0 breast cancer. This study found that older patients in the newly constructed high-risk group benefited from OS and BCSS benefits from PMRT, while for younger high-risk patients, there was only a benefit in terms of OS.

Outcomes with and without postmastectomy radiotherapy for pT3N0-1M0 breast cancer: An institutional experience

AIM

The objective of this study is to comprehensively evaluate the therapeutic efficacy of postmastectomy radiotherapy (PMRT) in treating patients with pT3N0-1M0 breast cancer within the context of modern therapeutic strategies.

METHODS

Clinical data from patients with pT3N0-1M0 breast cancer who underwent mastectomy from January 2005 to December 2018 at our institution were retrospectively analyzed.

RESULTS

The study involved a total of 222 participants, with 112 individuals undergoing PMRT and 110 individuals not receiving it. The median follow-up duration was 77 months (range: 6-171 months). The entire cohort demonstrated 5-year disease-free survival (DFS) and overall survival (OS) rates of 85.1% and 91.0%, respectively, along with a locoregional recurrence (LRR) rate as low as 7.2%. The PMRT group showed significantly better 5-year DFS (90.2% vs. 80.0%, p = 0.02) and OS (95.5% vs. 86.4%, p = 0.012) rates, as well as a lower LRR rate (4.5% vs. 10.0%, p = 0.122), compared to the group without PMRT. Cox regression analysis confirmed the independent prognostic significance of PMRT for both DFS (p = 0.040) and OS (p = 0.047). Following propensity score matching (PSM), the analysis included 100 matched patients, revealing an improved prognosis for those who received PMRT (DFS: p = 0.067; OS: p = 0.043).

CONCLUSIONS

Our study reveals favorable prognoses for pT3N0-1M0 breast cancer patients treated within contemporary therapeutic approaches. The pivotal role of PMRT in this context is evident. However, due to the retrospective design of our study and the relatively limited sample size, further investigation is imperative to validate and enhance these initial findings.

The Survival Effect of Chest Wall With or Without Regional Lymphatic Radiotherapy for Breast Cancer Patients With T3~4N0M0

Background

Peripheral lymphatic radiotherapy in patients with pT3N0M0 and pT4N0M0 breast cancer has been a matter of considerable debate among radiation oncologists. This is the first report in a non-Caucasian population.

Patients and Methods

The study included 165 pT3N0M0 and pT4N0M0 patients. Univariate, multivariate, propensity score matching (PSM), and Kaplan-Meier analyses were conducted to evaluate the survival of patients. We also review all the literature about regional lymph nodes radiation in T3-4N0M0 patients and summarize them with tables to compare with the present study.

Results

The median follow-up duration was 58.7 months. Multivariate analyses showed that advance T stage and grade were dependent poor prognostic factors for OS, DMFS, LRFS, and DFS between group A (chest wall radiation) and group B (chest wall and regional lymph nodes radiation). The overall survival (OS), disease-free survival (DFS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) rates were not significantly different between group A and group B. The 5-year OS rate was 92.3% vs 89.7% for group A and group B, respectively (P=0.819). The 5-year LRFS rate was 94.9% vs 94.3% for group A and group B, respectively (P=0.852). Fifty-four pairs of patients were selected after propensity score matching (PSM) analysis was conducted. There was also no significant difference between group A and group B in regard to the OS, DFS, LRFS, and DMFS rates after PSM. The patients included in previous studies were all Caucasians, and our study was focused on non-Caucasians. The cases of previous studies were 10 to 20 years ago, but our study has more recent cases. The radiotherapy techniques of previous studies were conventional, and the techniques used in our study were three-dimensional conformal radiotherapy (3DCRT) or intensity modulated radiotherapy (IMRT).

Conclusion

Both our study and previous studies suggested that regional lymph nodes radiation cannot improve the survival rate for breast cancer patients with T3-4N0M0 in non-Caucasian population. Advance T stage and grade were the dependent poor prognostic factors for T3-4N0M0 patients.

Outcomes in Patients with pT3N0M0 Breast Cancer with and without Postmastectomy Radiotherapy

Purpose

The role of adjuvant postmastectomy radiotherapy (PMRT) remains controversial for patients with pT3N0M0 breast cancer, especially when patients are treated with the updated adjuvant chemotherapy. Our study aimed to compare locoregional recurrence-free survival (LRFS), disease-free survival (DFS), and breast cancer-specific survival (BCSS) in pT3N0M0 patients with and without postmastectomy radiotherapy.

Patients and Methods

Between October 2000 and 8 September 2016, the database of the Breast Cancer Center of Shanghai yielded 114 patients with node-negative non-metastatic breast cancer larger than 5 cm. Univariate and multivariate analyses were performed to assess the risk factors for survivals. Differences between the two groups were compared using the Log rank test.

Results

Fifty-nine (51.8%) of the patients received adjuvant PMRT. The median follow-up was 62.3 months. Five-year LRFS was 100% in the PMRT group vs 98.1% in the non-PMRT group (P=0.17); 5-year DFS was 97.1% for the entire cohort, 98.0% for the PMRT group vs 96.2% for the non-PMRT group (P=0.18). Univariate analysis identified that family history of malignant tumors, lymphovascular invasion (LVI), or triple-negative breast cancer (TNBC) molecular subtype were associated with higher locoregional recurrence (LRR) (P<0.05). No PMRT was the only risk factor independently associated with poorer DFS (P=0.048) on multivariate analysis. No difference in BCSS was observed between the two groups.

Conclusion

The present study demonstrated a low LRR rate and good survival for node-negative breast cancer >5 cm. Patients with family history of malignant tumors, TNBC subtype, LVI positivity, or grade 3 disease are at high risk for LRR and might benefit from PMRT.

Prognostic validation and therapeutic decision-making of the AJCC eighth pathological prognostic staging for T3N0 breast cancer after mastectomy

BACKGROUND

T3N0 breast cancer might be a distinct clinical and biological entity, with higher heterogeneity and presenting diverse responses to locoregional and systemic therapy. The aim of the current study was to validate the prognostic effect and assess the treatment decision-making of the American Joint Committee on Cancer (AJCC) eighth pathological prognostic staging in T3N0 breast cancer after mastectomy.

METHODS

We retrospectively included 2465 patients with stage T3N0 breast cancer who had undergone mastectomy between 2010 and 2014 using the data from Surveillance, Epidemiology, and End Results program. The primary endpoint of this study was breast cancer-specific survival (BCSS).

RESULTS

Of the entire cohort, 76.0% of patients in the seventh AJCC staging system were restaged to the eighth AJCC pathological prognostic staging system. A total of 1431 (58.1%) and 1175 (47.7%) of them received chemotherapy and postmastectomy radiotherapy (PMRT), respectively. Pathological staging was an independent prognostic factor for BCSS. Using pathological prognostic stage IA as the reference, BCSS gradually became worse with increased hazard ratios. The 5-years BCSS was 96.9%, 95.5%, 91.1%, 85.6%, and 75.5% in pathological prognostic stage IA, IB, IIA, IIB, and IIIA breast cancers, respectively (P < .001). In pathological prognostic stage IA, IB, and IIA breast cancers, the receipt of PMRT or chemotherapy was not correlated with better BCSS. However, PMRT was correlated with better BCSS in pathological prognostic stage IIB disease (P = .006), but not in pathological prognostic IIIA disease. Moreover, chemotherapy was correlated with better BCSS in pathological prognostic stage IIIA disease (P = .006), but not in pathological prognostic stage IIB disease.

CONCLUSIONS

The eighth AJCC pathological prognostic staging system provides more risk stratification of T3N0 breast cancers after mastectomy and might affect individualized decision-making for chemotherapy and PMRT in this patient subset.

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.

National Evaluation of the New Commission on Cancer Quality Measure for Postmastectomy Radiation Treatment for Breast Cancer

BACKGROUND

Current guidelines recommend postmastectomy radiotherapy (PMRT) for patients with ≥4 positive lymph nodes and suggest strong consideration of PMRT in those with 1-3 positive nodes. These recommendations were incorporated into a Commission on Cancer quality measure in 2014. However, national adherence with these recommendations is unknown. Our objectives were to describe PMRT use in the United States in patients with stage I to III invasive breast cancer and to examine possible factors associated with the omission of PMRT.

METHODS

From the National Cancer Data Base, 753,536 mastectomies at 1123 hospitals were identified from 1998 to 2011. PMRT use over time was examined using random effects logistic regression analyses, adjusting for patient, tumor, and hospital characteristics. Analyses were stratified by nodal status (≥4 nodes positive, 1-3 nodes positive, node negative).

RESULTS

The proportion of patients receiving PMRT increased from 1998 to 2011 (>4 positive nodes: 56.2 to 66.6 %; 1-3 positive nodes: 28.0 to 39.1 %; node-negative: 8.3 to 10.0 %, p < 0.001 for all). In adjusted analyses, patients with ≥4 positive nodes were more likely to have PMRT omitted if they had smaller tumors. Patients with 1-3 positive nodes were more likely to have PMRT omitted if they had lower grade or smaller tumors. Irrespective of patients' nodal status, PMRT utilization rates decreased as age increased.

CONCLUSIONS

Though PMRT rates increased over time in patients with ≥4 and 1-3 positive nodes, PMRT in patients with ≥4 positive nodes remains underutilized. Feedback to hospitals using the new Commission on Cancer PMRT measure may help to improve adherence rates.

Postmastectomy radiation therapy in T3 node-negative breast cancer

BACKGROUND

In the absence of lymph node involvement, tumor size is arguably the most important prognostic factor for women with breast cancer. Radiation therapy use in the T3 node-negative population is controversial. We investigated the use of postmastectomy radiation therapy (PMRT) in women with T3 node-negative breast cancer.

METHODS

A retrospective cohort study was conducted by identifying women with T3 node-negative breast cancer from the 1988-2009 Surveillance, Epidemiology and End Results database. Our primary outcome was breast cancer-specific survival. Survival curves were generated using the Kaplan-Meier method. Cox proportional hazard ratios (HRs) and propensity score analysis were used to evaluate the impact on survival.

RESULTS

We identified 2874 patients with T3 node-negative breast cancer and 961 (33%) received PMRT and 1913 (67%) did not. Statistically significant differences were seen in adjuvant radiation therapy use based on patient age, marital status, tumor grade, tumor size, and receptor status (P < 0.05 for all). Overall survival was lower in the PMRT group in unadjusted analysis (crude HR, 0.718; 95% confidence interval [CI], 0.614-0.840); however, adjusted HRs demonstrated no difference in overall survival (adjusted HR, 0.898; 95% CI, 0.765-1.054). Unadjusted analysis of breast cancer-specific survival demonstrated no difference between those who received PMRT and those who did not (crude HR, 0.834; 95% CI, 0.682-1.021). Propensity score analysis demonstrated no difference in breast cancer-specific survival based on PMRT use (adjusted HR, 0.939; 95% CI, 0.762-1.157).

CONCLUSIONS

Analysis of the Surveillance, Epidemiology and End Results database suggests that receipt of PMRT is not clinically beneficial in T3 node-negative breast cancer.

Postmastectomy radiation therapy for T3N0: a SEER analysis

BACKGROUND

There is conflicting evidence regarding the benefit of postmastectomy radiation therapy (PMRT) for pathologic stage T3N0M0 breast cancers. We analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database to investigate the benefit of PMRT in this patient population.

METHODS

We queried the SEER database for T3N0M0 breast cancer patients diagnosed from 2000 to 2010 who underwent modified radical mastectomy. We excluded males, patients with unknown radiation timing/type, other primary tumors, and survival <6 months. A total of 2525 patients were included in the analysis. We performed univariate and multivariate statistical analysis using chi-square tests, log-rank tests, and Cox proportional hazards regression. The primary endpoints were overall survival (OS) and cancer-specific survival (CSS).

RESULTS

Of the 2525 patients identified, 1063 received PMRT. The median follow-up was 56 months (range, 6-131 months). On univariate analysis, PMRT improved OS (76.5% vs 61.8%, P<.01) and CSS (85.0% vs 82.4%, P<.01) at 8 years. The use of PMRT remained significant on multivariate analysis: PMRT improved OS (hazard ratio 0.63, P<.001) and CSS (hazard ratio 0.77, P = .045). Low tumor grade (P<.01) and marital status of "married" (P = .01) also was a predictor of improved CSS on multivariate analysis.

CONCLUSIONS

PMRT was associated with significant improvements in both CSS and OS in patients with T3N0M0 breast cancers treated with modified radical mastectomy from 2000 to 2010. PMRT should be strongly considered in T3N0M0 patients. Postmastectomy radiation therapy is associated with significant improvements in overall and cause-specific survival in patients with T3N0M0 breast cancers treated with modified radical mastectomy from 2000 to 2010 in the SEER database. Postmastectomy radiation therapy should be strongly considered for patients who have T3N0M0 tumors.

Progress and controversies: radiation therapy for invasive breast cancer

Radiation therapy is a critical component of the multidisciplinary management of invasive breast cancer. In appropriately selected patients, radiation not only improves local control, sparing patients the morbidity and distress of local recurrence, but it also improves survival by preventing seeding and reseeding of distant metastases from persistent reservoirs of locoregional disease. In recent years, considerable progress has been made toward improving our ability to select patients most likely to benefit from radiotherapy and to administer treatment in ways that maximize clinical benefit while minimizing toxicity and burden. This article reviews the role of radiation therapy in invasive breast cancer management, both after breast-conserving surgery and after mastectomy. It focuses particularly on emerging evidence that helps to define the clinical situations in which radiotherapy is indicated, the appropriate targets of treatment, and optimal approaches for minimizing both the toxicity and the burden of treatment, all in the context of the evolving surgical and systemic management of this common disease. It includes a discussion of new approaches in breast cancer radiotherapy, including hypofractionation and intensity modulation, as well as a discussion of promising avenues for future research.

Postmastectomy radiation therapy: an overview for the practicing surgeon

Locoregional control of breast cancer is the shared domain and responsibility of surgeons and radiation oncologists. Because surgeons are often the first providers to discuss locoregional control and recurrence risks with patients and because they serve in a key gatekeeping role as referring providers for radiation therapy, a sophisticated understanding of the evidence regarding radiotherapy in breast cancer management is essential for the practicing surgeon. This paper synthesizes the complex and evolving evidence regarding the role of radiation therapy after mastectomy. Although substantial evidence indicates that radiation therapy can reduce the risk of locoregional failure after mastectomy (with a relative reduction of risk of approximately two-thirds), debate persists regarding the specific subgroups who have sufficient risks of residual microscopic locoregional disease after mastectomy to warrant treatment with radiation. This paper reviews the evidence available to guide appropriate referral and patient decision making, with special attention to areas of controversy, including patients with limited nodal disease, those with large tumors but negative nodes, node-negative patients with high risk features, patients who have received systemic chemotherapy in the neoadjuvant setting, and patients who may wish to integrate radiation therapy with breast reconstruction surgery.

Post mastectomy radiation for large node negative breast cancer: time for a second look

Patients with node negative and large primary tumors ≥5cm comprise a rare entity of breast cancer patients for which clear management guidelines are not available. Data about the rates of loco-regional failures (LRF) in this patient population are scarce and reporting widely varying observations. Post Mastectomy Radiation Therapy (PMRT) for this group of patients is controversial. In this review we examined the available literature discussing the LRF rates in this clinical setting and the value of adding PMRT in their management.

Post-mastectomy radiation in large node-negative breast tumors: does size really matter?

Treatment decisions regarding local control can be particularly challenging for T3N0 breast tumors because of difficulty in estimating rates of local failure after mastectomy. Reports in the literature detailing the rates of local failure vary widely, likely owing to the uncommon incidence of this clinical situation. The literature regarding this clinical scenario is reviewed, including recent reports that specifically address the issue of local failure rates after mastectomy in the absence of radiation for large node-negative breast tumors.

Radiotherapy to the chest wall following mastectomy for node-negative breast cancer: a systematic review

BACKGROUND

Although nodal status is the major determinant of risk of locoregional relapse (LRR), other factors also contribute, and these assume a greater significance for those with node-negative breast cancer. Previous reviews of post-mastectomy radiotherapy have included studies using radiotherapy techniques or doses no longer considered clinically appropriate.

OBJECTIVES

To determine the effectiveness of post-mastectomy radiotherapy in women with node-negative breast cancer with particular reference to those patient and tumour factors which contribute to an increased risk of LRR.

METHODS

A systematic literature review was conducted. Trials using inadequate or orthovoltage radiotherapy were excluded. Data linking potential risk factors, either individually or in combination, to the occurrence of LRR were handled qualitatively. Data from randomised trials of post-mastectomy radiotherapy were included in a meta-analysis.

RESULTS

Baseline risk of LRR is increased in the presence of lymphovascular invasion, a grade 3 tumour, tumours greater than 2 cm or a close resection margin and in patients who are pre-menopausal or aged less than 50. Those with no risk factors have a baseline risk of LRR of approximately 5% or less rising to a risk of 15% or more for those with two or more risk factors. In the meta-analysis of three randomised trials of mastectomy and axillary clearance (667 patients), the addition of radiotherapy resulted in an 83% reduction in the risk of LRR (P < 0.00001) and in a 14% improvement in survival (P = 0.16).

CONCLUSION

The use of post-mastectomy radiotherapy for women with node-negative breast cancer requires re-evaluation. Radiotherapy should be considered for those with two or more risk factors.

Postmastectomy radiation therapy: indications and controversies

The indications and benefits of postmastectomy radiation therapy (PMRT) continue to evolve. Advances in systemic adjuvant therapy and targeted therapy for breast cancer are likely to play an increasingly important role in control of locoregional as well as distant disease. Ongoing scrutiny of patterns of chest wall failure will be required to define the net benefit derived from PMRT. This article discusses the 2001 American Society of Clinical Oncology guidelines for PMRT and current practices using PMRT in selected groups of patients who have breast cancer.

The role of postoperative radiotherapy in node negative breast cancer patients with pT3–T4 disease

AIMS

To evaluate the role of postmastectomy radiotherapy (PMRT) in patients with pT3-T4N0M0 breast cancer.

METHODS

156 patients with T3-T4N0M0 breast cancer were retrospectively analyzed.

RESULTS

Locoregional recurrences were seen in 17 of 156 patients with a median time for development of 27 months (5.7-248.7 months). Two of 9 patients who were not treated with post-operative radiation therapy had locoregional recurrence as compared with 16 of 147 patients receiving radiotherapy. In multivariate analysis, presence of locoregional recurrence was the only significant prognostic factor for overall survival (18% vs. 86%, p<0.001, RR=9.05). The patients with a median number of dissected lymph nodes >or=10 had a significantly better locoregional disease free survival rate as compared with patients with dissected lymph nodes <10 (90% vs. 78%, p=0.04). Chest wall recurrences were clearly higher in patients without chest wall RT since 5 of 49 patients without RT had recurrences in the chest wall region while only 4 of 107 who received chest wall RT had recurrence. However receiving RT to peripherical lymphatic regions had no additional effect on reducing recurrences in these regions (5% vs. 4%).

CONCLUSIONS

Due to the lack of phase III randomized trials directly addressing the role of postmastectomy radiotherapy in these stages, our series suggest that postmastectomy radiotherapy to the ipsilateral chest wall is recommended for patients with PT3N0 and T4N0 breast cancer. The need for irradiating axillary or supraclavicular region shall be neglected in patients who undergo sufficient axillary sampling.

Low local recurrence rate without postmastectomy radiation in node-negative breast cancer patients with tumors 5 cm and larger

PURPOSE

To assess the need for adjuvant radiotherapy following mastectomy for patients with node-negative breast tumors 5 cm or larger.

METHODS AND MATERIALS

Between 1981 and 2002, a total of 70 patients with node-negative breast cancer and tumors 5 cm or larger were treated with mastectomy and adjuvant systemic therapies but without radiotherapy at three institutions. We retrospectively assessed rates and risk factors for locoregional failure (LRF), overall survival (OS), and disease-free survival (DFS) in these patients.

RESULTS

With a median follow-up of 85 months, the 5-year actuarial LRF rate was 7.6% (95% confidence interval, 3%-16%). LRF was primarily in the chest wall (4/5 local failures), and lymphatic-vascular invasion (LVI) was statistically significantly associated with LRF risk by the log-rank test (p=0.017) and in Cox proportional hazards analysis (p=0.038). The 5-year OS and DFS rates were 83% and 86% respectively. LVI was also significantly associated with OS and DFS in both univariate and multivariate analysis.

CONCLUSIONS

This series demonstrates a low LRF rate of 7.6% among breast cancer patients with node-negative tumors 5 cm and larger after mastectomy and adjuvant systemic therapy. Our data indicate that further adjuvant radiation therapy to increase local control may not be indicated by tumor size alone in the absence of positive lymph nodes. LVI was significantly associated with LRF in our series, indicating that patients with this risk factor require careful consideration with regard to further local therapy.

Low Locoregional Recurrence Rate Among Node-Negative Breast Cancer Patients With Tumors 5 cm or Larger Treated by Mastectomy, With or Without Adjuvant Systemic Therapy and Without Radiotherapy: Results From Five National Surgical Adjuvant Breast and Bowel Project Randomized Clinical Trials

Purpose

Lymph node (LN) –negative breast cancer tumors ≥ 5 cm occur infrequently, and their optimal management is not well defined. In this study, we assess patterns of locoregional failure (LRF) in LN-negative patients who underwent mastectomy, either with or without adjuvant chemotherapy or hormonal therapy and without postmastectomy radiation therapy (PMRT).

Patients and Methods

Of 8,878 breast cancer patients enrolled onto National Surgical Adjuvant Breast and Bowel Project B-13, B-14, B-19, B-20, and B-23 node-negative trials, 313 had tumors that were 5 cm or larger (median, 5.5 cm; range, 5.0 to 15.5 cm) at pathology and were treated by mastectomy. Median follow-up time was 15.1 years. Therapy included adjuvant chemotherapy in 34.2% of patients; tamoxifen in 21.1%; chemotherapy plus tamoxifen in 19.2%; and no systemic therapy in 25.5%.

Results

Twenty-eight patients experienced LRF. The overall 10-year cumulative incidences of isolated LRF, LRF with and without distant failure (DF), and DF alone as first event were 7.1%, 10.0%, and 23.6%, respectively. Cumulative incidences for isolated LRF as first event for patients with tumors of 5 cm or more than 5 cm were 7.0% and 7.2%, respectively (P = .9). For patients who underwent no systemic treatment, chemotherapy alone, tamoxifen alone, or chemotherapy plus tamoxifen, the incidences were 12.6%, 5.6%, 4.6%, and 5.3%, respectively (P = .2). The majority of failures occurred on the chest wall (24 of 28 patients). Multivariate analysis did not identify significant prognostic factors for LRF.

Conclusion

In patients with LN-negative tumors ≥ 5 cm who are treated by mastectomy with or without adjuvant systemic therapy and no PMRT, LRF as first event remains low. PMRT should not be routinely used for these patients.

Skin-sparing mastectomy and immediate reconstruction is an acceptable treatment option for patients with high-risk breast carcinoma

BACKGROUND

Skin-sparing mastectomy (SSM) followed by immediate reconstruction is an effective treatment option for patients with early-stage breast carcinoma, but its use in patients with more advanced disease is controversial.

METHODS

A retrospective review was performed that included 38 consecutive patients with high-risk breast carcinoma who underwent SSM and immediate reconstruction (between July 1996 and January 2002). Tumor characteristics, type of reconstruction, margin status, timing of adjuvant therapy, postoperative complications, and incidence of recurrence were evaluated.

RESULTS

High-risk patients (Stage IIA [n=4 patients] Stage IIB [n=23 patients] Stage IIIA [n=8 patients] and Stage IIIB [n=3 patients]) underwent immediate reconstruction after SSM with the use of a transverse rectus abdominis myocutaneous flap (n=31 patients), a latissimus dorsi myocutaneous flap plus an implant (n=3 patients), or tissue expanders with subsequent implant placement (n=4 patients). The median follow-up was 52.9 months (range, 27.5-92.0 months), and the median time to recurrence has not yet been reached at the time of last follow-up. The median interval from surgery to the initiation of postoperative adjuvant therapy was 38 days (range, 25-238 days). Local recurrence was seen in 1 patient (2.6%), systemic recurrence in was seen in 10 patients (26.3%), and both local and distant metastases in were seen in 2 other patients (5.3%).

CONCLUSIONS

SSM with immediate reconstruction appeared to be an oncologically safe treatment option for high-risk patients with advanced stages of breast carcinoma. In addition to the aesthetic and psychological benefits of performing SSM with immediate reconstruction, local recurrence rates and disease-free survival were favorable when combined with the use of radiation therapy and adjuvant chemotherapy, as indicated.

Evidence-based indications for postmastectomy irradiation

The ASCO guidelines panel found that PMRT reduces the risks of both local-regional recurrence and distant recurrence, and improves survival rates for patients with invasive breast cancer with involved axillary lymph nodes receiving systemic therapy. The benefits of PMRT, however, vary with regards to particular patient subsets (such as those defined by the number of involved axillary nodes). The panel agreed that PMRT is indicated routinely for patients with four or more positive axillary nodes, tumors larger than 5 cm in size, or locally advanced cancers. There was insufficient evidence for the panel to make recommendations or suggestions for the use of PMRT for patients with T1-2 tumors with one to three positive axillary nodes or for all patients receiving neoadjuvant systemic therapy. Physicians and patients are encouraged to participate in randomized trials exploring such issues, such as the ongoing intergroup study for patients with one to three positive axillary nodes.

Postmastectomy radiotherapy: clinical practice guidelines of the American Society of Clinical Oncology

OBJECTIVE

To determine indications for the use of postmastectomy radiotherapy (PMRT) for patients with invasive breast cancer with involved axillary lymph nodes or locally advanced disease who receive systemic therapy. These guidelines are intended for use in the care of patients outside of clinical trials.

POTENTIAL INTERVENTION

The benefits and risks of PMRT in such patients, as well as subgroups of these patients, were considered. The details of the PMRT technique were also evaluated.

OUTCOMES

The outcomes considered included freedom from local-regional recurrence, survival (disease-free and overall), and long-term toxicity.

EVIDENCE

An expert multidisciplinary panel reviewed pertinent information from the published literature through July 2000; certain investigators were contacted for more recent and, in some cases, unpublished information. A computerized search was performed of MEDLINE data; directed searches based on the bibliographies of primary articles were also performed.

VALUES

Levels of evidence and guideline grades were assigned by the Panel using standard criteria. A "recommendation" was made when level I or II evidence was available and there was consensus as to its meaning. A "suggestion" was made based on level III, IV, or V evidence and there was consensus as to its meaning. Areas of clinical importance were pointed out where guidelines could not be formulated due to insufficient evidence or lack of consensus.

RECOMMENDATIONS

The recommendations, suggestions, and expert opinions of the Panel are described in this article.

VALIDATION

Seven outside reviewers, the American Society of Clinical Oncology (ASCO) Health Services Research Committee members, and the ASCO Board of Directors reviewed this document.