Clinical investigation: Regional nodal failure patterns in breast cancer patients treated with mastectomy without radiotherapy

Effects of axillary dose restriction on plan quality and acute radiation dermatitis in breast cancer radiotherapy

Axillary dose restriction (ADR) is rarely implemented in breast cancer radiotherapy by radiation oncologists to minimize exposure to organs at risk (OARs), particularly the axilla. This prospective randomized controlled study aims to evaluate the efficacy of ADR in improving plan quality (PQ) and its impact on acute radiation dermatitis (ARD) in breast cancer radiotherapy. The study recruited breast cancer patients who required postoperative radiotherapy but did not have an indication for axillary irradiation. Delineation and dosimetric assessment of the axilla (Axilla Levels I-III and Axillary Cavity) were performed in all cases, with ADR implemented randomly. ADR involved restricting the mean axilla dose to 40-45 Gy during radiotherapy. The outcomes assessed included the ARD grades (both overall and axillary) and dose-volume parameters of PQ including skin V35. The study enrolled 87 patients, who were randomly divided into two groups: Group I (50 patients) received ADR, while Group C (37 patients) did not. ADR was found to be significantly associated with reduced exposure doses to the axilla and ipsilateral lung, specifically in patients with modified radical mastectomy (MRM). Results of other PQ parameters, such as D95, V93, V95, V100, V107 for the planning target volume (PTV), V30, Dmean for the heart, Dmax for the spinal cord, and V5 for the ipsilateral lung, demonstrated potential benefits in alleviating doses to these OARs while maintaining optimized PQ, although these results were not statistically significant. However, no statistically significant correlation between ADR and severe ARD (≥ Grade 2) or skin V35 was established, either in the total patient population or in subgroups. Additionally, a multivariable logistic regression for severe ARD was conducted, with ADR and skin V35 included as predictive factors. Only older age was found to be significantly associated with severe ARD. Implementing ADR in breast cancer radiotherapy not only protects the axilla and ipsilateral lung but also maintains optimized PQ, specifically in MRM patients, though it shows no evidence of alleviating ARD. Adopting ADR may be considered a valuable option in breast cancer radiotherapy.

The impact of bolus on clinical outcomes for post-mastectomy breast cancer patients treated with IMRT: data from China

PURPOSE

This study aims to investigate the effects of chest wall bolus in intensity-modulated radiotherapy (IMRT) technology on clinical outcomes for post-mastectomy breast cancer patients.

MATERIALS AND METHODS

This retrospective study included patients with invasive carcinoma ((y)pT0-4, (y)pN0-3) who received photon IMRT after mastectomy at the Affiliated Hospital of Qingdao University from 2014 to 2019. The patients were divided into two groups based on whether they received daily bolus application or not, and the baseline characteristics were matched using propensity score matching (PSM). Cumulative incidence (CI) of local recurrence (LR), locoregional recurrence (LRR), overall survival (OS) and disease-free survival (DFS) were evaluated with a log-rank test. Acute skin toxicity and late radiation pneumonia was analyzed using chi-square test.

RESULTS

A total of 529 patients were included in this study, among whom 254 (48%) patients received bolus application. The median follow-up time was 60 months. After matching, 175 well-paired patients were selected. The adjusted 5-year outcomes (95% confidence interval) in patients treated with and without bolus were, respectively: CI of LR 2.42% (0.04-4.74) versus 2.38% (0.05-4.65), CI of LRR 2.42% (0.04-4.74) versus 3.59% (0.73-6.37), DFS 88.12% (83.35-93.18) versus 84.69% (79.42-90.30), OS 94.21% (90.79-97.76) versus 95.86% (92.91-98.91). No correlation between bolus application and skin toxicity (P = 0.555) and late pneumonia (P = 0.333) was observed.

CONCLUSIONS

The study revealed a low recurrence rate using IMRT technology. The daily used 5 mm chest wall bolus was not associated with improved clinical outcomes.

Extranodal extension, an international survey on its evaluation and reporting in breast cancer patients

Lymph node metastasis is the most important prognostic factor for breast cancer patients. In addition to the number of nodes involved and the largest metastatic focus, extranodal extension (ENE) is also used to subclassify breast cancer patients into different risk groups. More recently, pathologists are required to report the size/extent of ENE per the new CAP guideline, as it seems to be associated with more axillary nodal burden and/or a worse prognosis. Although the definition of ENE is largely understood and agreed upon among pathologists around the world, evaluation and reporting for the size of ENE are not. To understand current practice, we conducted an international survey among pathologists who are interested in breast pathology. A total of 70 pathologists responded. The results showed that (1) 98% of the participants reported the presence or absence of ENE and 61% also reported the size of ENE in millimeter (mm). (2) There was no uniform method of measuring the size of ENE; 47% measured the largest dimension regardless of orientation, while 30% measured the largest perpendicular distance from the capsule. (3) The most common factors affecting the accuracy in diagnosis of ENE are the presence of lymphovascular invasion (LVI), lack of capsule integrity, and the presence of fatty hilar or fatty replacement of a lymph node. (4) 71% felt that the H&E stain is adequate to evaluate ENE, deeper levels and IHC analysis for vascular and cytokeratin markers can be helpful if needed. (5) 75% agreed that there is an urgent need to standardize the measurement and reporting for ENE. Our survey highlights the variation in ENE evaluation and the need for its standardization in breast cancer patients with axillary node metastasis.

Lymph nodal radiotherapy in breast cancer: what are the unresolved issues?

Introduction: Sentinel lymph node biopsy (SLNB) is the gold standard in invasive breast cancer. Axillary dissection (ALND) is controversial in some presentations.Areas covered: Key questions were formulated and explored focused on four different scenarios in adjuvant axillary radiation management in early and locally advanced breast cancer. Answers to these questions were searched in MEDLINE, PubMed from June 1946 to August 2020. Clinical trials, retrospective studies, international guidelines, meta-analysis, and reviews were explored.Expert opinion: Analysis according to biological disease characteristics is necessary to establish the impact of ALND avoidance in unexpectedly positive SLNB (pN1) in cN0 patients. A low-risk probability of axillary recurrence was observed if axillary radiotherapy (ART) or ALND were offered without impact on outcomes. Adjuvant RNI in pT1-3 pN1 treated with mastectomy or BCS should be proposed in unfavorable disease and risk factors. In ycN0 after NACT, SLNB can be offered in selected cases or ALND should be performed. After SLNB post-NACT (ypN1), ALND and adjuvant radiotherapy are mandatory.

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.

A retrospective analysis on metastatic rate of the internal mammary lymph node and its clinical significance in adjuvant radiotherapy of breast cancer patients

Background

There is a discrepancy about the metastatic rate of internal mammary lymph nodes (IMNs) between clinical and pathologic findings. We aimed to investigate the metastatic rate of IMNs and to provide recommendations on target volume delineation of IMNs for adjuvant radiotherapy in breast cancer patients.

Methods

We retrospectively analyzed data from 114 breast cancer patients treated with surgery without adjuvant radiotherapy who developed local and/or regional lymph node recurrence/metastasis at our institute from January 2015 to January 2019. Patients with widely lung or pleural metastases were excluded. We first analyzed the recurrence rate with the chest wall, the metastatic rate of internal mammary/anterior mediastinal, ipsilateral axillary and supraclavicular lymph nodes, and then investigated the distribution of the IMNs.

Results

Among the 114 included patients, the recurrence rate with the chest wall, metastatic rate of IMNs, IMNs/anterior mediastinal lymph nodes, ipsilateral axillary lymph nodes, and the ipsilateral supraclavicular lymph nodes was 43, 37.7, 59.6, 12.3, and 22.8%, respectively. The metastatic IMNs were mainly located from the first to the second intercostal space. However, metastatic lymph nodes could also be observed above the upper edge of the first rib.

Conclusions

The metastatic rate is high in the IMNs and irradiation of the internal mammary lymphatic chain is required. It is suggested that the upper bound of the internal mammary lymphatic chain should be up to the subclavian vein with a 5-mm margin, thus connecting to the caudal border of supraclavicular clinical target volume in breast cancer patients at high risk of recurrence.

Dosimetric comparison between volumetric-modulated arc therapy and a hybrid volumetric-modulated arc therapy and segmented field-in-field technique for postmastectomy chest wall and regional lymph node irradiation

Decreasing radiotoxicity to the heart, lungs, and contralateral breast has proven to lower the risk of secondary malignancy and improve overall outcomes when treating chest wall (CW) and regional lymph nodes in postmastectomy breast cancer patients. In this retrospective study, 11 postmastectomy patients were selected and planned with a novel hybrid treatment method and a traditional volumetric arc therapy (VMAT) approach for comparison. This hybrid technique was able to optimize tangential beams to minimize heart dose and the VMAT contribution to improve dose conformity around the planning target volume (PTV). Overall, this hybrid technique produced more homogenous target dose coverage and demonstrated a decrease of integral dose to organs at risk (OAR), while the VMAT technique demonstrated a higher affinity for maintaining dose conformity. Further observation of dose distributions also revealed that the hybrid plans were more effective in sparing low-dose spread to healthy tissue in both right- and left-sided cases. This observation was made evident by the reduction in heart V5 and D_mean, decreases in all parameters regarding the contralateral lung, as well as all values other than the V20 of the ipsilateral lung. This unique hybrid planning technique could present an alternative to standard intensity-modulated radiation therapy (IMRT) planning when treating postmastectomy CW and regional lymph nodes, as it has shown the capacity to decrease cardiac, lung, and contralateral breast toxicity while maintaining quality PTV coverage.

Clinical Significance of Lymph-Node Ratio in Determining Supraclavicular Lymph-Node Radiation Therapy in pN1 Breast Cancer Patients Who Received Breast-Conserving Treatment (KROG 14-18): A Multicenter Study

This study evaluated the clinical significance of the lymph-node ratio (LNR) and its usefulness as an indicator of supraclavicular lymph-node radiation therapy (SCNRT) in pN1 breast cancer patients with disease-free survival (DFS) outcomes. We retrospectively analyzed the clinical data of patients with pN1 breast cancer who underwent partial mastectomy and taxane-based sequential adjuvant chemotherapy with postoperative radiation therapy in 12 hospitals (n = 1121). We compared their DFS according to LNR, with a cut-off value of 0.10. The median follow-up period was 66 months (range, 3–112). Treatment failed in 73 patients (6.5%) and there was no significant difference in DFS between the SCNRT group and non-SCNRT group. High LNR (>0.10) showed significantly worse DFS in both univariate and multivariate analyses (0.010 and 0.033, respectively). In a subgroup analysis, the effect of SCNRT on DFS differed significantly among patients with LNR > 0.10 (p = 0.013). High LNR can be used as an independent prognostic factor for pN1 breast cancer patients treated with partial mastectomy and postoperative radiotherapy. It may also be useful in deciding whether to perform SCNRT to improve DFS.

Comparison of 4th ESO-ESMO international consensus guidelines for advance breast cancer and Chinese anti-cancer association committee of Breast Cancer Society guideline

The primary aim of the international advance breast cancer (ABC) guidelines are to guide treatment decisions in many different healthcare settings, but need adaptations due to different access to care. These guidelines are based on the most up-to-date evidence. However, Chinese experts have a different national condition and policies to face. The Chinese Anti-Cancer Association Committee of Breast Cancer Society guideline (CBCS guideline) is to guide treatments and to reflect unmet needs of Chinese breast cancer patients. Although, most of the recommendations in the two guidelines are the same, some of them are different. In this article, with regard to country-specific peculiarities, a working group of Chinese breast cancer experts compare the similarities and differences between the ABC guideline and CBCS guideline and commented on the voting results of the ABC panelists. We also discuss why these differences exist, such as lack of access, different tumor biology and epidemiology, and even different culture. The money which patients have to pay out of pocket for their medical cost and the availability of drugs lie at the heart of the issues of guideline differences.

Can Axillary and Supraclavicular Radiotherapy be Avoided after Breast-Conserving Surgery and Axillary Dissection in Women with Multiple Involved Axillary Nodes?: Experience at the European Institute of Oncology

Aims and background

Although some guidelines recommend adjuvant radiotherapy (RT) to the axilla and supraclavicular nodes if 4 or more axillary nodes are involved, the current practice at our Institute is not to irradiate the axilla but to perform complete axillary dissection in which all 3 Berg levels are removed. We performed a retrospective analysis of patients with 4 or more axillary nodes involved and sufficient follow-up to provide indications as to whether our current treatment is adequate.

Methods

We retrospectively analyzed 287 T1–T3 patients with a median follow-up of 5 years and 4 or more involved nodes treated by quadrantectomy and breast RT but no axillary RT; supraclavicular RT was given only when prognostic factors were unfavorable.

Results

A total of 170 (59.2%) patients did not receive supraclavicular RT, while 117 (40.8%) patients received supraclavicular irradiation. No patient received axillary RT. After a median follow-up of 5 years (range, 4–105 months), 4.7% had died and 13.5% had developed distant metastases in the no supraclavicular RT group, compared to 12.0% dead (P = 0.028 log rank) and 24.8% (P = 0.201 log rank) in the supraclavicular RT group. No patients with supraclavicular RT developed supraclavicular metastases compared to 4 in the no supraclavicular RT group. There were no axillary recurrences.

Conclusions

Complete axillary dissection appears adequate treatment in patients with 4 or more involved nodes. The low breast recurrence rate also suggests that breast conservation is adequate treatment in such patients. Supraclavicular RT appears to reduce the number of supraclavicular metastases but confers no survival advantage. Although a small number of cases were examined in this retrospective single-center series, all received highly uniform treatment.

Use of regional nodal irradiation and its association with survival for women with high-risk, early stage breast cancer: A National Cancer Database analysis

Purpose

The role of regional nodal irradiation (RNI) for patients with breast cancer remains controversial, particularly on the basis of nodal involvement. Using the National Cancer Database, we aimed to validate published data on whether expanding treatment fields from whole-breast irradiation (WBI) to encompass the regional nodes (WBI+RNI) affected overall survival (OS) for patients with node-positive (pN1-3) or high-risk node-negative (pN0) breast cancer treated with breast-conserving surgery and adjuvant chemotherapy.

Methods and materials

Women diagnosed with invasive breast cancer between 2004 and 2012 who met the selection criteria for the National Cancer Institute of Canada MA.20 trial were identified and stratified by receipt of RNI. Propensity score matching was used to compare 1:1 matched pairs of patients. Five-year OS was estimated using the Kaplan-Meier method. We used multivariate logistic regression to predict receipt of WBI+RNI and a multivariable Cox model to examine associations between patients' demographic, tumor, and treatment characteristics and OS using double robust estimation.

Results

Of 23,567 patients, 6,920 (29%) received WBI+RNI and 16,647 (71%) WBI. Median follow-up was 56 months. Use of WBI+RNI increased from 25.2% in 2004 to 32.2% in 2012 (P < .001). Patients receiving WBI+RNI more often had negative hormone-receptor status, ≥5 cm tumors and >1 involved node, and were not privately insured. For all patients, the 5-year OS rates were 90.8% with WBI+RNI versus 92.6% with WBI (P < .001). In the matched cohort (n = 10,922), the corresponding 5-year OS rates were 92% and 91.9% (P = .45), respectively. On multivariate analysis, WBI+RNI did not affect OS in the matched cohort (hazard ratio, 1.02; 95% confidence interval, 0.89-1.17, P = .76), regardless of pathologic nodal status.

Conclusions

In this large retrospective analysis, use of WBI+RNI did not affect 5-year OS rates for women with high-risk, early stage breast cancer undergoing breast-conserving surgery and adjuvant chemotherapy, regardless of nodal status, which confirms the findings of the MA.20 trial.

Outcomes of Post Mastectomy Radiation Therapy in Patients Receiving Axillary Lymph Node Dissection After Positive Sentinel Lymph Node Biopsy

PURPOSE

We sought to determine the rate of postmastectomy radiation therapy (PMRT) among women treated with axillary lymph node dissection (ALND) after positive sentinel lymph node (SLN) biopsy results and to establish the effect of negative ALND results and PMRT on locoregional recurrence (LRR) and overall survival (OS).

METHODS AND MATERIALS

All patients were treated with mastectomy and ALND after positive SLN biopsy results. All patients had clinical N0 or NX disease at the time of mastectomy and received no neoadjuvant therapy. The presence of lymphovascular space invasion, presence of multifocality, number of positive SLNs and non-SLNs, clinical and pathologic stage, extranodal extension, age, and use of PMRT were evaluated for significance regarding the rates of OS and LRR.

RESULTS

A total of 345 patients were analyzed. ALND after positive SLN biopsy results was negative in 235 patients (68.1%), and a total of 112 patients (32.5%) received radiation therapy. On multivariate analysis, only pathologic stage III predicted for lower OS (hazard ratio, 3.32; P<.001). The rate of 10-year freedom from LRR was 87.9% and 95.3% in patients with positive ALND results and patients with negative ALND results, respectively. In patients with negative ALND results with ≥3 positive SLNs, the rate of freedom from LRR was 74.7% compared with 96.7% in those with <3 positive SLNs (P=.009). In patients with negative ALND results, ≥3 positive SLNs predicted for an increase in LRR on multivariate analysis (hazard ratio, 10.10; P=.034).

CONCLUSIONS

A low proportion of cT1-2, N0 patients with positive SLNs who undergo mastectomy receive PMRT after ALND. Even in this low-risk cohort, patients with ≥3 positive SLNs and negative ALND results are at increased risk of LRR and may benefit from PMRT.

Postmastectomy radiation therapy after neoadjuvant chemotherapy: review and interpretation of available data

Postmastectomy radiotherapy (PMRT) has been shown to decrease locoregional recurrence and improve overall survival in patients with tumors greater than 5 cm or positive nodes. Because neoadjuvant chemotherapy (NAC) can cause significant downstaging, the indications for PMRT in the setting of NAC remain controversial and thus careful consideration of clinical stage at presentation, pathologic response to NAC, and other clinical characteristics, such as grade and biomarker status is required. The current review synthesizes both prospective and retrospective data to provide evidence for recommending PMRT after NAC for patients presenting with cT3-4 disease, cN2-3 disease, and residual nodal disease, as well as rationale for omitting PMRT in patients with cT1-2N0-1 disease who achieve a pathologic complete response. Other scenarios, including nodal complete response in the presence of other risk factors, are also explored. The topics of pre-NAC clinical staging and pathologic axillary nodal staging are reviewed, and radiation portal design is briefly discussed.

Five Simultaneous Primary Tumors in a Single Patient: A Case Report and Review of the Literature

Multiple primary malignancies (MPMs) are present when a patient is diagnosed with more than one primary malignancy and when each tumor is histologically unrelated to the others. MPMs are considered synchronous when they present within 6 months of one another. Here, we report the case of a 57-year-old woman with a past medical history significant for melanoma in 1988, who presented in 2014 with 5 distinct tumors within 4 months: malignant melanoma of the right popliteal fossa, invasive lobular breast carcinoma, diffuse large B cell lymphoma, nodular lymphocyte predominant Hodgkin lymphoma, and a giant cell tumor of tendon sheath/pigmented villonodular synovitis. We discuss her treatment and also present a brief review of the literature. The incidence of MPMs appears to be on the rise, which demands an interdisciplinary, multimodal, and personalized approach to care.

Optimal approach in early breast cancer: Radiation therapy

Radiation therapy significantly reduces by at least 70% the relative risk of local and regional recurrences for breast cancer after surgery. A positive influence on overall survival has been clearly demonstrated, especially for patients with a high absolute risk for locoregional recurrences. However, this is partially counterbalanced by late toxicity (dependent upon the radiation dose) especially to cardiac structures. Apart from this toxicity, a clear influence of radiation-therapy-related factors on functional and cosmetic outcome has also been demonstrated. Over time, technical improvements have led to a marked reduction in dose to the neighbouring organs, with a consequent drop in acute and late toxicity. This has also allowed the introduction of shorter radiation schedules, lowering the burden of treatment to the patient and the hospital. Several tools, techniques and guidelines have been developed to optimise the balance between the desired reduction in recurrence rates and side effects.

The multidisciplinary team should discuss all available treatment options for every individual breast cancer patient. Individualisation of the selection of the optimal combination of treatments, depending on patient and tumour-related factors, is of utmost importance. Apart from direct tumour-related outcomes, cosmesis and potential side effects have to be taken into account. Counselling should include known risk factors for survival and complications, including comorbidity.

Benefit of post-mastectomy radiotherapy of the supra-/infraclavicular lymphatic drainage area in breast cancer patients

BACKGROUND

This study investigated the survival benefit of radiotherapy (RT) of the supra- and infraclavicular lymphatic drainage area in Chinese women with T1-2N1M0 breast cancer receiving mastectomy.

METHODS

A total of 593 cases were retrospectively reviewed from 1998 to 2007. The relationship between supra- or infraclavicular fossa relapse (SCFR) and post-operative RT at the supra-/infraclavicular lymphatic drainage area was evaluated.

RESULTS

The majority of patients (532/593; 89. 8%) received no RT while 61 patients received RT. The median follow-up was 85 months. Among patients without RT, 54 (10. 2%) developed recurrence in the chest wall or ipsilateral SCFR. However, none of the 61 patients who underwent RT demonstrated SCFR. One patient who received RT (1. 6%) experienced recurrence in the chest wall. Univariate analysis revealed that age and molecular subtype (both P < 0. 05) were two prognostic factors related to supraclavicular and infraclavicular fossa relapse-free survival (SFRFS). Multivariate analysis revealed that only Her-2 positive status (P = 0. 011) was an independent predictor of SFRFS. RT had no influence on distant metastasis (P = 0. 328) or overall survival (P = 0. 541). SCFR significantly affected probability of distant metastasis (P < 0. 001) and overall survival (P < 0. 001).

CONCLUSION

Although RT was not significantly associated with SFRFS, postoperative RT was significantly associated with a lower locoregional (i. e. , supraclavicular/infraclavicular and chest wall) recurrence rate. SCFR significantly influenced distant metastasis-free survival, which significantly influenced the overall survival of T1- 2N1M0 breast cancer patients after mastectomy. Thus, prophylactic RT is recommended in T1-2N1M0 breast cancer patients, especially those who have Her-2 positive lesions.

No clear effect of postoperative radiotherapy on survival of breast cancer patients with one to three positive nodes: a population-based study

BACKGROUND

In published radiotherapy trials, the failure rate in the control arm among patients with one to three positive nodes is high compared with that seen with modern adjuvant treatments. Therefore, the generalizability of the results has been questioned. The aim of the present study was to compare relative survival in breast cancer patients between two Swedish regions with screening mammography programs and adjuvant treatment guidelines similar with the exception of the indication of radiotherapy for patients with one to three positive nodes.

PATIENTS AND METHODS

Between 1989 and 2006, breast cancer patients were managed very similarly in the west and southeast regions, except for indication for postoperative radiotherapy. In patients with one to three positive nodes, postmastectomy radiotherapy was generally given in the southeast region (89% of all cases) and generally not given in the west region (15% of all cases). For patients with one to three positive nodes who underwent breast-conserving surgery, patients in the west region had breast radiotherapy only, while patients in the southeast region had both breast and lymph nodes irradiated.

RESULTS

The 10-year relative survival for patients with one to three positive lymph nodes was 78% in the west region and 77% in the southeast region (P = 0.12). Separate analyses depending on type of surgery, as well as number of examined nodes, also revealed similar relative survival.

CONCLUSION

Locoregional postoperative radiotherapy has well-known side-effects, but in this population-based study, there was little or no influence of this type of radiotherapy on survival when one to three lymph nodes were involved.

Benefits, risks, and safety of external beam radiation therapy for breast cancer

Breast cancer is a common and complex disease often necessitating multimodality care. Breast cancer may be treated with surgical resection, radiotherapy (RT), and systemic therapy, including chemotherapy, hormonal therapy, and targeted therapies, or a combination thereof. In the past 50 years, RT has played an increasingly significant role in the treatment of breast cancer, resulting in improvements in locoregional control and survival for women undergoing mastectomy who are at high risk of recurrence, and allowing for breast conservation in certain settings. Although radiation provides significant benefit to many women with breast cancer, it is also associated with risks of toxicity, including cardiac and pulmonary toxicity, lymphedema, and secondary malignancy. RT techniques have advanced and continue to evolve dramatically, offering increased precision and reproducibility of treatment delivery and flexibility of treatment schedule. This increased sophistication of RT offers promise of improved outcomes by maintaining or improving efficacy, reducing toxicity, and increasing patient access and convenience. A review of the role of radiation therapy in breast cancer, its associated toxicities and efforts in toxicity reduction is presented.

Dosimetric analysis of the brachial plexus among patients with breast cancer treated with post-mastectomy radiotherapy to the ipsilateral supraclavicular area: report of 3 cases of radiation-induced brachial plexus neuropathy

Background

The purpose of this study was to evaluate the brachial plexus (BP) dose of postmastectomy radiotherapy (PMRT) to the ipsilateral supraclavicular (ISCL) area, and report the characteristics of radiation-induced brachial plexus neuropathy (RIBPN).

Methods

The BP dose of 31 patients who received adjuvant PMRT to the ISCL area and chest wall using three-dimensional conformal radiotherapy (3DCRT) and the records of 3 patients with RIBPN were retrospectively analyzed based on the standardized Radiation Therapy Oncology Group-endorsed guidelines. The total dose to the ISCL area and chest wall was 50 Gy in 25 fractions.

Results

Patients with a higher number of removed lymph nodes (RLNs) had a higher risk of RIBPN (hazard ratio [HR]: 1.189, 95% confidence interval [CI]: 1.005-1.406, p = 0.044). In 31 patients treated with 3DCRT, the mean dose to the BP without irradiation to the ISCL area was significantly less than that with irradiation to the ISCL area (0.97 ± 0.20 vs. 44.39 ± 4.13 Gy, t = 136.75, p <0.001). In the 3DCRT plans with irradiation to the ISCL area and chest wall, the maximum dose to the BP was negatively correlated with age (r = −0.40, p = 0.026), body mass index (BMI) (r = −0.44, p = 0.014), and body weight (r = −0.45, p = 0.011). Symptoms of the 3 patients with RIBPN occurred 37–65 months after radiotherapy, and included progressive upper extremity numbness, pain, and motor disturbance. After treatment, 1 patient was stable, and the other 2 patients’ symptoms worsened.

Conclusions

The incidence of RIBPN was higher in patients with a higher number of RLNs after PMRT. The dose to the BP is primarily from irradiation of the ISCL area, and is higher in slim and young patients. Prevention should be the main focus of managing RIBPN, and the BP should be considered an organ-at-risk when designing a radiotherapy plan for the ISCL area.

Influence of Individualized Stabilization on the Consistency of Supraclavicular Fossa Positioning in Breast Radiation Therapy: A Retrospective Study

INTRODUCTION

The accurate stabilization of breast patients who are also undergoing supraclavicular fossa treatment is essential and can be challenging. Discrepancy in setup error for these patients often lies with the position of the clavicle in relationship with other anatomic structures. This study was performed to assess how individualized stabilization can improve patient's stability and reproducibility.

METHODS

Thirty patients stabilized with an individualized vacfix located on a Civco wing board (Civco Medical Solutions, Kalona, IA) were compared with 30 patients stabilized in the traditional manner on a Civco breast board (Civco Medical Solutions). Each of these patients underwent daily imaging using the Varian Clinac iX On-board Imaging System (Varian Medical Systems, Palo Alto, CA), and image mismatch data for each session were collected. Additionally, the relationship between the clavicle and vertebrae was assessed for each stabilization solution on a daily basis. Statistical analysis of this data was then performed using a mixed effects approach to take account of data grouping by patient specifically for the displacement error in each direction.

RESULTS

The use of an individualized vacfix decreased the overall systematic and random setup errors and displayed a reduction in the standard deviation of setup error. Patients positioned using breast board stabilization with the clavicle as the match method were exposed in the longitudinal direction to a systematic error of a 95% confidence interval (CI) of 2.6-4.5 mm and a random error of a 95% CI of 2.7-3.2 mm. This was significantly reduced for vacfix stabilization with a systematic error of a 95% CI of 1.2-2.3 mm and a random error of a 95% CI of 1.8-2.3 mm. These data amount to a reduction of the systematic error by 40% (P = .02) and a random error by 25% (P = .003) when using the vacfix method compared with the breast board. The data displaying the relationship between the clavicle and other anatomy within the treatment volume appear to be more consistent with the individualized vacfix approach.

CONCLUSIONS

Reproducible and consistent stabilization for the breast/supraclavicular fossa technique is vital in terms of ensuring accurate patient position. Analysis of the setup error for clavicle and spinous process matching strongly indicates a reduction in both the systematic and random setup error achieved by the vacfix. This illustrates the increased stability and reproducibility of patient positioning when an individualized vacfix is used.

The extent of extracapsular extension may influence the need for axillary lymph node dissection in patients with T1-T2 breast cancer

BACKGROUND

Whether extracapsular extension (ECE) of tumor in the sentinel lymph node (SLN) is an indication for axillary lymph node dissection (ALND) in patients managed by American College of Surgeons Oncology Group Z0011 criteria is controversial. Here we examine the correlation between ECE in the SLN and disease burden in the axilla.

METHODS

Patients meeting Z0011 clinicopathologic criteria (pT1-2, cN0 with <3 positive SLNs) were selected from a prospectively maintained database (2006-2013). Chart review documented the presence and extent of ECE. Neoadjuvant chemotherapy patients were excluded. Comparisons were made by presence and extent (≤2 vs. >2 mm) of ECE.

RESULTS

Of 11,730 patients, 778 were pT1-2, cN0 with <3 positive SLNs without ECE, and 331 (2.8 %) had ECE. Of these, 180 had ≤2 mm and 151 had >2 mm of ECE. Patients with ECE were older (57 vs. 54 years; p = 0.001) and had larger (2.0 vs. 1.7 cm; p < 0.0001), multifocal (p = 0.006), hormone receptor-positive tumors (p = 0.0164) with lymphovascular invasion (p < 0.0001). Presence and extent of ECE were associated with greater axillary disease burden; 20 and 3 % of patients with and without ECE, respectively, had ≥4 additional positive nodes at completion ALND (p < 0.0001), and 33 % of patients with >2 mm ECE had ≥4 additional positive nodes at completion ALND, compared with 9 % in the <2 mm group (p < 0.0001). On multivariate analysis, >2 mm of ECE was the strongest predictor of ≥4 positive nodes at completion ALND (odds ratio 14.2).

CONCLUSIONS

Presence and extent of ECE were significantly correlated with nodal tumor burden at completion ALND, thus suggesting that >2 mm of ECE may be an indication for ALND or radiotherapy when applying Z0011 criteria to patients with metastases in <3 SLNs. ECE reporting should be standardized to facilitate future studies.

Comparison of two treatment strategies for irradiation of regional lymph nodes in patients with breast cancer: Lymph flow guided portals versus standard radiation fields

AIM AND BACKGROUND

Radiotherapy being an essential part of breast cancer treatment, we evaluate various radiotherapy strategies in patients with breast cancer.

MATERIALS AND METHODS

Lymph node (LN) scintigraphy was performed in 172 primary patients with BC. LN visualization started 30-360 min after intratumoral injection of 75-150 MBq of 99mTc-nanocolloids. Our standard recommendation for postoperative radiotherapy in patients with LN invasion by BC were as follows: for patients with external localization of tumour - breast + axillary (Ax) + sub-supraclavicular (SSCL) regions; with internal localization - all above + internal mammary nodes (IM). Proposed strategy of lymph flow guided radiotherapy is based on the assumption that only regions that contain 'hot' LNs must be included in a treatment volume.

RESULTS

Among 110 patients with external localization of BC, Ax LNs were visualized in all cases and in 62 patients it was the only region with 'hot' LN. Twenty-three patients (20.9%) had drainage to Ax + SSCL, 12 (10.9%) - Ax + IM, 13 (11.8%) - Ax + SSCL + IM regions. After the visualization of lymph flow patterns, standard treatment volume was changed in 87/110 cases (79.1%): in 56.4%, reduced, in 22.7%, enlarged or changed. In 62 patients with tumours in internal quadrants, we revealed the following patterns of lymph-flow: only to the Ax region in 23 (37.1%); Ax + IM, 13 (21%); Ax + SSCL, 15 (24.2%); Ax + IM + ISSCL, 11 (17.7%) cases. After lymph-flow visualization, the standard irradiation volume was reduced in 53/62 (85.5%) cases.

CONCLUSION

Visualization of an individual lymph flow pattern from BC can be used for the optimization of standard fields used for irradiation of regional LNs.

Risk of positive nonsentinel nodes in women with 1-2 positive sentinel nodes related to age and molecular subtype approximated by receptor status

We examine risk of positive nonsentinel axillary nodes (NSN) and ≥4 positive nodes in patients with 1-2 positive sentinel nodes (SN) by age and tumor subtype approximated by ER, PR, and Her2 receptor status. Review of two institutional databases demonstrated 284 women undergoing breast conservation between 1997 and 2008 for T1-2 tumors and 1 (229) or 2 (55) positive SN followed by completion dissection. The median number of SN and total axillary nodes removed were 2 (range 1-10) and 14 (range 6-37), respectively. The rate of positive NSNs (p = 0.5) or ≥4 positive nodes (p = 0.6) was not associated with age. NSN were positive in 36% of luminal A, 26% of luminal B, 21% of TN and 38% of Her2+ (p = 0.4). Four or more nodes were present in 17% of luminal A, 13% luminal of B, 0% of TN and 29% of Her2+ (p = 0.1). Microscopic extracapsular extension was significantly associated with having NSNs positive (55% versus 24%, p < 0.0001) and with having total ≥4 nodes positive (33% versus 7%, p < 0.0001). In a population that was largely eligible for ACOSOG Z0011, the risk of positive NSN or ≥4 positive nodes did not vary significantly by age. The TN subgroup had the lowest risk of both positive NSN or ≥4 positive nodes. Several high risk groups with >15% risk for having ≥4 positive nodes were identified. Further data is needed to confirm that ACOSOG Z0011 results are equally applicable to all molecular phenotypes.

DEGRO practical guidelines: radiotherapy of breast cancer III--radiotherapy of the lymphatic pathways

AIM

The purpose of this work is to update the practical guidelines for adjuvant radiotherapy of the regional lymphatics of breast cancer published in 2008 by the breast cancer expert panel of the German Society of Radiation Oncology (DEGRO).

METHODS

A comprehensive survey of the literature concerning regional nodal irradiation (RNI) was performed using the following search terms: "breast cancer", "radiotherapy", "regional node irradiation". Recent randomized trials were analyzed for outcome as well as for differences in target definition. Field arrangements in the different studies were reproduced and superimposed on CT slices with individually contoured node areas. Moreover, data from recently published meta-analyses and guidelines of international breast cancer societies, yielding new aspects compared to 2008, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the German interdisciplinary S3 guidelines updated in 2012, this paper addresses indications, targeting, and techniques of radiotherapy of the lymphatic pathways after surgery for breast cancer.

RESULTS

International guidelines reveal substantial differences regarding indications for RNI. Patients with 1-3 positive nodes seem to profit from RNI compared to whole breast (WBI) or chest wall irradiation alone, both with regard to locoregional control and disease-free survival. Irradiation of the regional lymphatics including axillary, supraclavicular, and internal mammary nodes provided a small but significant survival benefit in recent randomized trials and one meta-analysis. Lymph node irradiation yields comparable tumor control in comparison to axillary lymph node dissection (ALND), while reducing the rate of lymph edema. Data concerning the impact of 1-2 macroscopically affected sentinel node (SN) or microscopic metastases on prognosis are conflicting.

CONCLUSION

Recent data suggest that the current restrictive use of RNI should be scrutinized because the risk-benefit relationship appears to shift towards an improvement of outcome.

Dosimetric evaluation of integrated IMRT treatment of the chest wall and supraclavicular region for breast cancer after modified radical mastectomy

To investigate the dosimetric characteristics of irradiation of the chest wall and supraclavicular region as an integrated volume with intensity-modulated radiation therapy (IMRT) after modified radical mastectomy. This study included 246 patients who received modified radical mastectomy. The patients were scanned with computed tomography, and the chest wall (with or without the internal mammary lymph nodes) and supraclavicular region were delineated. For 143 patients, the chest wall and supraclavicular region were combined as an integrated planning volume and treated with IMRT. For 103 patients, conventional treatments were employed with 2 tangential fields for the chest wall, abutting a mixed field of 6-MV x-rays (16Gy) and 9-MeV electrons (34Gy) for the upper supraclavicular region. The common prescription dose was 50Gy/25Fx/5W to 90% of the target volume. The dosimetric characteristics of the chest wall, the supraclavicular region, and normal organs were compared. For the chest wall target, compared with conventional treatments, the integrated IMRT plans lowered the maximum dose, increased the minimum dose, and resulted in better conformity and uniformity of the target volume. There was an increase in minimum, average, and 95% prescription dose for the integrated IMRT plans in the supraclavicular region, and conformity and uniformity were improved. The V30 of the ipsilateral lung and V10, V30, and mean dose of the heart on the integrated IMRT plans were lower than those of the conventional plans. The V5 and V10 of the ipsilateral lung and V5 of the heart were higher on the integrated IMRT plans (p < 0.05) than on conventional plans. Without an increase in the radiation dose to organs at risk, the integrated IMRT treatment plans improved the dose distribution of the supraclavicular region and showed better dose conformity and uniformity of the integrated target volume of the chest wall and supraclavicular region.

Postmastectomy radiation therapy

Many women undergo mastectomy as treatment of their breast cancer either because of personal preference or because of tumor-related factors making mastectomy the preferred surgical option. The use of postmastectomy radiation therapy has been shown to decrease the risk of local recurrence and in some cases improve overall survival. Decisions regarding the need for postmastectomy radiation therapy can be complex and rely on careful review of many factors. Lymph node status, tumor size, tumor grade, receptor status, presence or absence of lymphovascular space invasion, Her-2/neu status, margin width, and patient age all need to be considered when making recommendations for or against postmastectomy radiation therapy. In this article, we provide a review of the relevant literature pertaining to postmastectomy radiation therapy in order to help guide this decision-making process.

Prophylactic supraclavicular radiotherapy after surgery in high-risk n1 breast cancer

OBJECTIVES

To evaluate the role of prophylactic supraclavicular radiotherapy (RT) by comparing the clinical outcomes of locoregional recurrence (LRR) in high-risk N1 breast cancer.

METHODS

We performed a retrospective comparison study of 250 high-risk N1 breast cancer patients treated at two institutions. Patients were considered to be high-risk when they had more than two of the following risk factors: lymphovascular invasion, extracapsular extension, metastasis to more than two axillary lymph nodes (ALNs), or level II or higher ALN metastasis. We compared two groups treated with different adjuvant RT fields for the purpose of prophylactic supraclavicular RT (SCRT).

RESULTS

Among the 250 patients, 97 patients received SCRT while 153 did not. During follow-up, 32 patients (7 in the SCRT and 25 in the no-SCRT group) had recurrence, and LRR developed in 19 patients, 18 of whom had not received SCRT. In multivariate analysis, SCRT [hazard ratio (HR) 0.072; p = 0.011] and chemotherapy regimen (cyclophosphamide, Adriamycin, and taxane; TAC) were the significant prognostic factors in LRR-free survival (HR 0.385; p = 0.046), and chemotherapy regimen also showed significance for distant metastasis-free survival (HR 0.399; p = 0.037).

CONCLUSIONS

Use of prophylactic SCRT may reduce the risk of LRR in patients with high-risk N1 breast cancer.

Patterns and risk factors for locoregional failures after mastectomy for breast cancer: an International Breast Cancer Study Group report

BACKGROUND

Rates and risk factors of local, axillary and supraclavicular recurrences can guide patient selection and target for postmastectomy radiotherapy (PMRT).

PATIENTS AND METHODS

Local, axillary and supraclavicular recurrences were evaluated in 8106 patients enrolled in 13 randomized trials. Patients received chemotherapy and/or endocrine therapy and mastectomy without radiotherapy. Median follow-up was 15.2 years.

RESULTS

Ten-year cumulative incidence for chest wall recurrence of >15% was seen in patients aged <40 years (16.1%), with ≥4 positive nodes (16.5%) or 0-7 uninvolved nodes (15.1%); for supraclavicular failures >10%: ≥4 positive nodes (10.2%); for axillary failures of >5%: aged <40 years (5.1%), unknown primary tumor size (5.2%), 0-7 uninvolved nodes (5.2%). In patients with 1-3 positive nodes, 10-year cumulative incidence for chest wall recurrence of >15% were age <40, peritumoral vessel invasion or 0-7 uninvolved nodes. Age, number of positive nodes and number of uninvolved nodes were significant parameters for each locoregional relapse site.

CONCLUSION

PMRT to the chest wall and supraclavicular fossa is supported in patients with ≥4 positive nodes. With 1-3 positive nodes, chest wall PMRT may be considered in patients aged <40 years, with 0-7 uninvolved nodes or with vascular invasion. The findings do not support PMRT to the dissected axilla.

Radiation treatment in pathologic n0-n1 patients treated with neoadjuvant chemotherapy followed by surgery for locally advanced breast cancer

Purpose

This study evaluated the treatment results and the necessity to irradiate the supraclavicular lymph node (SCN) region in pathological N0-N1 (pN0-N1) patients with locally advanced breast cancer treated with neoadjuvant chemotherapy (NAC) followed by surgery and radiotherapy (RT).

Methods

Between 1996 and 2008, 184 patients with initial tumor size >5 cm or clinically positive lymph nodes were treated with NAC followed by surgery and RT. Among these patients, we retrospectively reviewed 98 patients with pN0-N1. Mastectomy was performed in 55%. The pathological lymph node stage was N0 in 49% and N1 in 51%. All patients received adjuvant RT to chest wall or breast and 56 patients (57%) also received RT to the SCN region (SCNRT).

Results

At 5 years, locoregional recurrence (LRR)-free survival, distant metastasis-free survival, disease-free survival (DFS), and overall survival rates were 93%, 83%, 81%, and 91%, respectively. In pN0 patients, LRR was 7% in SCNRT- group and 5% in SCNRT+ group. In pN1 patients, LRR was 7% in SCNRT- group and 6% in SCNRT+ group. There was no significant difference of LRR, regardless of SCNRT. However, in pN1 patients, there were more patients with poor prognostic factors in the SCNRT+ group compared to SCNRT- group. These factors might be associated with worse DFS in the SCNRT+ group, even though RT was administered to the SCN region.

Conclusion

Our study showed the similar LRR, regardless of SCNRT in pN0-pN1 breast cancer patients after NAC followed by surgery. Prospective randomized trial is called for to validate the role of SCNRT.

Comparison of clinical outcome of breast cancer patients with T1-2 tumor and one to three positive nodes with or without postmastectomy radiation therapy

OBJECTIVE

The value of postmastectomy radiation therapy for breast cancer patients with T1-2 tumor and one to three positive nodes remains controversial. The purpose of this retrospective study was to compare the clinical outcomes of breast cancer patients with T1-2 and one to three positive nodes with and without postmastectomy radiation therapy.

METHODS

Between May 1990 and June 2008, of 318 breast cancer patients with T1-2 and one to three positive nodes who had undergone modified radical mastectomy, 163 received postmastectomy radiation therapy and 155 did not. The clinico-pathologic characteristics were analyzed for clinical outcomes including loco-regional recurrence, distant metastasis, disease-free survival and overall survival.

RESULTS

During the median follow-up period of 102 months, the clinical outcomes in postmastectomy radiation therapy versus no-postmastectomy radiation therapy groups were as follows: loco-regional recurrence rate (3.1 versus 11.0%, P= 0.006); distant metastasis rate (20.9 versus 27.7%, P= 0.152); 10-year disease-free survival rate (73.8 versus 61.3%, P= 0.001); and 10-year overall survival rate (82.1 versus 76.1%, P= 0.239). Through a multivariate analysis, a positive nodal ratio of ≥25% (hazard ratio= 4.571, P= 0.003) and positive lymphovascular invasion (hazard ratio= 2.738, P= 0.028) were found to be independent poor prognostic predictors of loco-regional recurrence. The reduction in loco-regional recurrence (hazard ratio= 0.208, P= 0.004) by postmastectomy radiation therapy was found to be significant.

CONCLUSIONS

On the basis of our results, postmastectomy radiation therapy is highly recommended for breast cancer patients with T1-2 and one to three positive nodes, especially for high-risk subgroups with a positive nodal ratio of ≥25% and positive lymphovascular invasion, not only for reducing loco-regional recurrence but also for improving disease-free survival.

[Axillary lymph node irradiation in breast cancer: state of the art]

Place of axillary radiotherapy in the management of patients with breast cancer remains debated. While the prognostic value of axillary lymph node extension has been largely demonstrated, the benefit of axillary treatment is more uncertain. Large clinical trials having demonstrated the benefit of adjuvant radiotherapy in advanced breast cancer comprised large nodal irradiation, including axillary area. Analyzing the true benefit of axillary radiotherapy is rendered difficult by heterogeneity of series, particularly when focusing on the extent of lymph node dissection. Although adjuvant axillary radiotherapy is usually recommended in patients with insufficient lymph node dissection or with bulky axillary involvement, the prognosis in these patients remains poor by metastatic evolution and such strategy exposes to increased toxicity and functional sequels. Further assessments should better define the optimal indications and the true benefit of axillary radiotherapy.

Using nodal ratios to predict risk of regional recurrences in patients treated with breast conservation therapy with 4 or more positive lymph nodes

Purpose. The value of nodal ratios (NRs) as a prognostic variable in breast cancer is continually being demonstrated. The purpose of this study was to use NR in patients with ≥4+ nodes to assess a correlation of NR with regional (lymph node) recurrence. Methods. Inclusion criteria was ≥8 nodes dissected with ≥4+ nodes after breast conservation therapy. Of 1060 patients treated from 1975 to 2003 who had a minimum of 8 nodes dissected, 273 were node+; 56 patients had ≥4+ involved nodes and were the focus of this study. Nodal ratios were calculated for each patient and grouped into 3 categories: high (≥70%), intermediate (40%–69%) and low (<40%). Each nodal ratio was correlated with patterns of local, regional, and distant failures and OS. Results. Outcomes for the entire cohort were BRFS-83%, NRFS-93%, DMFS-61%, and OS 63% at 10 yrs. The OS, DMFS, and NRFS correlated with N2 (4–9 nodes+) versus N3 (≥10+) status but did not correlate with BRFS, as expected. When evaluating NR, 18 pts had high NR (>70%). Only 3 patients experienced nodal recurrences, all within previously radiated supraclavicular fields. All 3 in-field regional failures occurred in the N3 group of patients with NR >70%. All were treated with a single AP field prescribed to a dose of 46 Gy at a standard depth of 3 cm. Conclusions. In this group of N2/N3 patients treated with BCT, we were able to identify patients at high risk for regional failures as those with high NR of >70% and ≥10+ nodes. While these findings need to be reproduced in larger datasets, this group of patients with NR of >70% in 4 or more positive axillary lymph nodes may benefit from meticulous targeting of regional nodes, dose escalation, and/or more intensive systemic therapies.

Patterns and risk factors of locoregional recurrence in T1-T2 node negative breast cancer patients treated with mastectomy: implications for postmastectomy radiotherapy

PURPOSE

Postmastectomy radiation therapy (PMRT) can reduce locoregional recurrences (LRR) in high-risk patients, but its role in the treatment of lymph node negative (LN-) breast cancer remains unclear. The aim of this study was to identify a subgroup of T1-T2 breast cancer patients with LN- who might benefit from PMRT.

METHODS AND MATERIALS

We retrospectively reviewed 1,136 node-negative T1-T2 breast cancer cases treated with mastectomy without PMRT at the Massachusetts General Hospital between 1980 and 2004. We estimated cumulative incidence rates for LRR overall and in specific subgroups, and used Cox proportional hazards models to identify potential risk factors.

RESULTS

Median follow-up was 9 years. The 10-year cumulative incidence of LRR was 5.2% (95% CI: 3.9-6.7%). Chest wall was the most common (73%) site of LRR. Tumor size, margin, patient age, systemic therapy, and lymphovascular invasion (LVI) were significantly associated with LRR on multivariate analysis. These five variables were subsequently used as risk factors for stratified analysis. The 10-year cumulative incidence of LRR for patients with no risk factors was 2.0% (95% CI: 0.5-5.2%), whereas the incidence for patients with three or more risk factors was 19.7% (95% CI: 12.2-28.6%).

CONCLUSION

It has been suggested that patients with T1-T2N0 breast cancer who undergo mastectomy represent a favorable group for which PMRT renders little benefit. However, this study suggests that select patients with multiple risk factors including LVI, tumor size ≥2 cm, close or positive margin, age ≤50, and no systemic therapy are at higher risk of LRR and may benefit from PMRT.

Long-term outcomes in patients with isolated supraclavicular nodal recurrence after mastectomy and doxorubicin-based chemotherapy for breast cancer

PURPOSE

To examine the outcome of patients who developed an isolated locoregional recurrence (LRR) involving the supraclavicular fossa (SCV) after initial treatment with modified radical mastectomy and chemotherapy.

METHODS AND MATERIALS

Records from 140 breast cancer patients treated on five prospective trials with mastectomy and doxorubicin-based chemotherapy, with or without radiation, who developed a LRR were reviewed. Kaplan-Meier survival times were calculated using date of LRR as time zero.

RESULTS

The median follow-up after LRR was 2.9 years (N = 140; interquartile range, 1.3-6.6 years). In all, 47 of 140 patients (34%) had an SCV component to their LRR. These patients had lower 3-y distant metastasis-free survival (40% vs. 54%, p = 0.003) and overall survival (49% vs. 69%, p = 0.04) than patients without an SCV component. Multivariate analysis revealed that LRR involving an SCV component (hazard ratio, 1.96, p = 0.004) and patients with lymphovascular space invasion in their primary tumors (hazard ratio, 1.65, p = 0.029) were independently associated with a poor distant metastasis-free survival. However, among 23 patients with isolated SCV recurrence, Overall survival was not statistically significantly different between isolated chest wall recurrence and isolated SCV recurrence. Patients with isolated SCV recurrence displayed a median follow-up of 3.3 years (IR, 1.2-5.2). Only 6 LRR of 23 patients were treated with aggressive local therapy, including surgery, chemotherapy, and radiation (alone or in combination).

CONCLUSIONS

Although breast cancer recurrence with SCV involvement carries a high risk of distant metastasis and death, among women with recurrence limited to the SCV alone, overall survival after isolated SCV recurrence can be long (25% >5 years).

Radiotherapy of the regional lymph nodes: shooting at the sheriff?

The role of immune surveillance in controlling the spread of breast cancer to the regional nodes is poorly understood. In theory regional nodal irradiation (RNI) might compromise this host function. However the clinical evidence suggests that the risk of regional recurrence is lower in patients with early breast cancer whose axilla has been irradiated compared to no axillary treatment. The role of RNI after breast conserving surgery has not been well studied. A policy of level III clearance and only irradiating the axilla for residual disease and a selective policy of axillary irradiation in node positive patients after sentinel node biopsy or lower axillary node sample is recommended. Irradiation of the medial supraclavicular fossa after axillary dissection is suggested where there are four or more nodes involved on axillary dissection. There is little data to inform selection of patients for RNI after neoadjuvant systemic therapy. The role of postmastectomy radiotherapy (PMRT) was largely established on the basis of comprehensive RNI. It is unclear whether irradiating less than the chest wall and peripheral lymphatics confers the same level of benefit. The role of PMRT in women with 1-3 involved nodes remains controversial and investigational. Biological factors such as oestrogen and progesterone receptor status and HER-2 protein expression may play a role in determining benefits from PMRT. The role of internal mammary nodal irradiation is unclear. The individualisation of RNI based on molecular and genetic factors should be a priority for research. The benefits of RNI need to be carefully balanced against the risks of cardiotoxicity, pneumonitis, lymphoedema, brachial plexopathy and secondary malignancy.