The value of radiotherapy on metastatic internal mammary nodes in breast cancer. Results on a large series

Hybrid VMAT-3DCRT as breast cancer treatment improvement tool

Radiation therapy is an important tool in the treatment of breast cancer and can play a crucial role in improving patient outcomes. For breast cancer, if the technique has been for a long time the use of 3DCRT, clinicians have seen the management evolve greatly in recent years. Field-in-field and IMRT approaches and more recently dynamic arctherapy are increasingly available. All of these approaches are constantly trying to improve tumour coverage and to preserve organs at risk by minimising the doses delivered to them. If arctherapy allows a considerable reduction of high doses received by healthy tissues, no one can deny that it also leads to an increase of low doses in tissues that would not have received any with other techniques. We propose a hybrid approach combining the robustness of the 3DCRT approach and the high technicality and efficiency of arctherapy. Statistical tests (ANOVA, Wilcoxon, determination coefficient, ROC, etc.) allow us to draw conclusions about the possibility of using the hybrid approach in certain cases (right breast, BMI [Formula: see text], age [Formula: see text], target volume [Formula: see text] cc, etc.). Depending on the breast laterality and patients morphological characteristics, hybridization may prove to be a therapeutic tool of choice in the management of breast cancer in radiotherapy.

Internal mammary node involvement in patients with axilla-negative early breast cancer: a narrative review

Early breast cancer staging involves radiological and pathological evaluation of the tumour and regional lymph nodes. The internal mammary nodes (IMN) are an important site of possible metastasis and influence disease stage and prognosis. However, the recommendation for routine IMN assessment remains unclear. Internal mammary sentinel lymph node biopsy (SLNB) is associated with increased morbidity and an unknown survival benefit. Furthermore, the IMN are traditionally thought to be involved only synchronous with, or following, axillary node (AXN) metastasis. The aim of this review is to determine the prevalence of IMN metastasis in patients with axilla-negative early breast cancer. A narrative review of studies assessing IMN metastasis was performed. The literature search was completed using the database Medline (Ovid). Twenty-two retrospective studies were identified. The studies included data from SLNB, US, MRI, PET/CT and opportunistic biopsy during free-flap reconstruction (FFR). The prevalence of isolated IMN metastasis ranged from 1.2% to 17.9%.

Internal Mammary Lymph Node Biopsy during Microsurgical Breast Reconstruction: A Prospective Study

BACKGROUND

 Accurate assessment of regional lymph node basins is critical for oncological management of breast cancer. The internal mammary lymph node (IMLN) basin directly drains the medial pole of the breast, but biopsy is not commonly performed. While the axillary sentinel lymph node sample remains the standard of care, the majority of patients who have been found to have a positive IMLN biopsy have simultaneously had negative axillary sentinel lymph nodes. This study prospectively examines routine IMLN biopsy during microsurgical breast reconstruction.

METHODS

 An IRB-approved study of routine IMLN biopsies in 270 consecutive patients who underwent microsurgical breast reconstruction was performed from July 1, 2018, to June 1, 2021. Recorded data included unilateral or bilateral breast reconstruction, unilateral or bilateral IMLN sampling, patient demographics, disease stage, and pathologic findings of IMLN.

RESULTS

 The majority of patients, 240 of 270 patients (88.9%), had bilateral reconstruction. Overall, 5 out of 270 (1.9%) patients had positive IMLN; one of these patients had positive axillary sentinel lymph nodes. The IMLN biopsy results in two of the five patients affected the clinical course as they were upstaged and required chemoradiation.

CONCLUSION

 Direct visualization of the internal mammary lymph nodes during dissection of the recipient vessels for microsurgical breast reconstruction allows for convenient sampling, with minimal donor site morbidity and enhances the therapeutic management of patients in whom nodal involvement is present. As such, the authors recommend IMLN sampling.

Value of Ultrasound-Guided Biopsy in Evaluating Internal Mammary Lymph Node Metastases in Breast Cancer

OBJECTIVES

This retrospective study aimed to assess the value of a real-time, ultrasound-guided biopsy in evaluating internal mammary lymph nodes (IMLNs) in breast cancer.

METHODS

Patients who were diagnosed with breast cancer and underwent real-time, ultrasound-guided core-needle biopsy (CNB) or fine-needle aspiration (FNA) in suspected IMLN metastasis were retrospectively analyzed. Patient information and ultrasonographic images were reviewed and correlated with pathology results.

RESULTS

Of the 164 IMLNs that were subjected to CNB, 131 were positive for metastasis by histopathologic confirmation, 8 were negative, and 25 were insufficient. By FNA, 84 IMLNs were regarded as positive for metastasis, 4 were negative, and 4 were insufficient. In total, there were 215 (83.98%) metastatic IMLNs, 12 benign IMLNs, and 29 unconfirmed by histopathology. There were statistically significant differences in the success of puncture sampling and detection of IMLN metastasis between the CNB and FNA groups (P < .05). There were no significant complications reported after FNA or CNB, including bleeding, nerve injury, infection, pneumothorax, or hemothorax.

CONCLUSIONS

Our study showed that ultrasonography accurately detected nodes that were likely to be malignant IMLNs, and that real-time, ultrasound-guided CNB and FNA are accurate and valuable techniques for the determination of status in breast cancer patients. Moreover, performing ultrasound-guided CNB and FNA on suspicious IMLN metastasis does not have additional severe complications.

Gated Radiotherapy Development and its Expansion

One of the most important challenges in treatment of patients with cancerous tumors of chest and abdominal areas is organ movement. The delivery of treatment radiation doses to tumor tissue is a challenging matter while protecting healthy and radio sensitive tissues. Since the movement of organs due to respiration causes a discrepancy in the middle of planned and delivered dose distributions. The moderation in the fatalistic effect of intra-fractional target travel on the radiation therapy correctness is necessary for cutting-edge methods of motion remote monitoring and cancerous growth irradiancy. Tracking respiratory milling and implementation of breath-hold techniques by respiratory gating systems have been used for compensation of respiratory motion negative effects. Therefore, these systems help us to deliver precise treatments and also protect healthy and critical organs. It seems aspiration should be kept under observation all over treatment period employing tracking seed markers (e.g. fiducials), skin surface scanners (e.g. camera and laser monitoring systems) and aspiration detectors (e.g. spirometers). However, these systems are not readily available for most radiotherapy centers around the word. It is believed that providing and expanding the required equipment, gated radiotherapy will be a routine technique for treatment of chest and abdominal tumors in all clinical radiotherapy centers in the world by considering benefits of respiratory gating techniques in increasing efficiency of patient treatment in the near future. This review explains the different technologies and systems as well as some strategies available for motion management in radiotherapy centers.

Outcome of radiotherapy for clinically overt metastasis to the internal mammary lymph node in patients receiving neoadjuvant chemotherapy and breast cancer surgery

PURPOSE

This study was aimed to assess the outcome of radiotherapy and determine prognostic factors for survival in breast cancer patients with clinically overt metastasis to the internal mammary lymph node (IMN+).

METHODS

We retrospectively reviewed the medical records of 193 patients with IMN + breast cancer who received neoadjuvant chemotherapy (NAC), breast surgery without internal mammary lymph node (IMN) dissection, and postoperative radiotherapy at 9 hospitals between 2009 and 2013. Breast-conserving surgery or mastectomy was performed after taxane-based NAC. Radiotherapy was administered to the whole breast/chest wall and regional nodes. IMN-covering radiotherapy was performed in 92.2% of patients with median dose of 58.4 Gy (range, 44.9-69.1 Gy). The overall survival (OS), disease-free survival (DFS), and IMN failure-free survival (IMNFFS) were analyzed.

RESULTS

After median follow-up of 71 months, 9 patients (4.7%) developed IMN failure and simultaneous distant metastasis. The 5-year DFS, OS, and IMNFFS was 68.6%, 81.8%, and 95.3%, respectively. Non-triple-negative breast cancer, Ki-67 ≤ 10%, pathological complete response (CR) in tumor and axillary node, and radiologic CR of IMN after NAC were significant factors for predicting higher DFS; however, IMN radiation dose was not significant determinants for DFS. The 5-year DFS of patients with IMN-dose ≤ 50.0 Gy and those with >50.0 Gy was 86.7% and 76.7%, respectively (p = 0.41).

CONCLUSIONS

A multimodality strategy including NAC, breast surgery, and IMN-covering radiotherapy was effective for patients with overt IMN + breast cancer. Even without an IMN dissection, most patients were IMN failure-free with an IMN-focusing radiotherapy.

Internal mammary and medial supraclavicular lymph node chain irradiation in stage I-III breast cancer (EORTC 22922/10925): 15-year results of a randomised, phase 3 trial

BACKGROUND

10-year results from several studies showed improved disease-free survival and distant metastasis-free survival, reduced breast cancer-related mortality, and variable effects on overall survival with the addition of partial or comprehensive regional lymph node irradiation after surgery in patients with breast cancer. We present the scheduled 15-year analysis of the European Organisation for Research and Treatment of Cancer (EORTC) 22922/10925 trial, which aims to investigate the impact on overall survival of elective internal mammary and medial supraclavicular (IM-MS) irradiation.

METHODS

EORTC 22922/10925, a randomised, phase 3 trial done across 46 radiation oncology departments from 13 countries, included women up to 75 years of age with unilateral, histologically confirmed, stage I-III breast adenocarcinoma with involved axillary nodes or a central or medially located primary tumour. Surgery consisted of mastectomy or breast-conserving surgery and axillary staging. Patients were randomly assigned (1:1) centrally using minimisation to receive IM-MS irradiation at 50 Gy in 25 fractions (IM-MS irradiation group) or no IM-MS irradiation (control group). Stratification was done for institution, menopausal status, site of the primary tumour within the breast, type of breast and axillary surgery, and pathological T and N stage. Patients and investigators were not masked to treatment allocation. The primary endpoint was overall survival analysed according to the intention-to-treat principle. Secondary endpoints were disease-free survival, distant metastasis-free survival, breast cancer mortality, any breast cancer recurrence, and cause of death. Follow-up is ongoing for 20 years after randomisation. This study is registered with ClinicalTrials.gov, NCT00002851.

FINDINGS

Between Aug 5, 1996, and Jan 13, 2004, we enrolled 4004 patients, of whom 2002 were randomly assigned to the IM-MS irradiation group and 2002 to the no IM-MS irradiation group. At a median follow-up of 15·7 years (IQR 14·0-17·6), 554 (27·7%) patients in the IM-MS irradiation group and 569 (28·4%) patients in the control group had died. Overall survival was 73·1% (95% CI 71·0-75·2) in the IM-MS irradiation group and 70·9% (68·6-72·9) in the control group (HR 0·95 [95% CI 0·84-1·06], p=0·36). Any breast cancer recurrence (24·5% [95% CI 22·5-26·6] vs 27·1% [25·1-29·2]; HR 0·87 [95% CI 0·77-0·98], p=0·024) and breast cancer mortality (16·0% [14·3-17·7] vs 19·8% [18·0-21·7]; 0·81 [0·70-0·94], p=0·0055) were lower in the IM-MS irradiation group than in the control group. No significant differences in the IM-MS irradiation group versus the control group were seen for disease-free survival (60·8% [95% CI 58·4-63·2] vs 59·9% [57·5-62·2]; HR 0·93 [95% CI 0·84-1·03], p=0·18), or distant metastasis-free survival (70·0% [67·7-72·2] vs 68·2% [65·9-70·3]; 0·93 [0·83-1·04], p=0·18). Causes of death between groups were similar.

INTERPRETATION

The 15-year results show a significant reduction of breast cancer mortality and any breast cancer recurrence by IM-MS irradiation in stage I-III breast cancer. However, this is not converted to improved overall survival.

FUNDING

US National Cancer Institute, Ligue Nationale contre le Cancer, and KWF Kankerbestrijding.

Regional nodal irradiation for early breast cancer; clinical benefit according to risk stratification

Three recently published prospective trials on regional nodal irradiation (RNI) in early breast cancer showed a reduction on breast cancer mortality, any first breast recurrence and/or distant recurrence rate. The positive outcomes of the modern trials reflect the development in radiotherapy by being more precise nowadays in radiation dose delivery to the lymph nodes, while reducing the radiation dose to heart and lungs. The possibility of axillary radiotherapy (ART) to replace axillary node dissection (ALND) after positive sentinel node (SLNB) biopsy is explored in a few trials. In the AMAROS trial both ALND and ART provide excellent and comparable LRR in SN+ patients. While the lymphedema was 2 times higher after ALND compared to ART. The ACOSOG Z0011 10 years results did not show a significant difference in locoregional recurrence rate or survival. These equal results were seen despite that in 27.4% of the patients had additional positive nodes removed beyond SLN in the patients who received axillary dissection (ALND). The IBCSG 23-01 phase III trial showed that there is no need for extra treatment of the axilla after micro-metastases in SLNB, however in this trial nearly all patients received breast irradiation including part of the axilla, often combined with adjuvant therapy. The introduction of neo- adjuvant systemic treatment (NACT) may lead to less RNI in early breast cancer, especially as NACT leads to pCR in axillary lymph nodes in about one third of the patient.

Internal Mammary Sentinel Lymph Node Biopsy in Clinically Axillary Lymph Node-Positive Breast Cancer: Diagnosis and Implications for Patient Management

BACKGROUND

Routine performance of internal mammary sentinel lymph node biopsy (IM-SLNB) remains a subject of debate due to no clinical relevance in breast cancer, because it was performed only in clinically axillary lymph node (ALN)-negative patients. In this study, IM-SLNB was performed in clinically ALN-positive patients, and its impact on nodal staging and therapeutic strategy were subsequently analyzed.

METHODS

Clinically ALN-positive patients who underwent IM-SLNB were enrolled in this prospective study. Statistical analysis was performed using Chi square test, Mann-Whitney U and logistic regression models with a significance level of 0.05.

RESULTS

Among the 352 recruited patients, the internal mammary sentinel lymph node (IMSLN) visualization rate of patients who received initial surgery and neoadjuvant systemic therapy (NST) was 71.9% (123/171) and 33.1% (60/181), respectively. The 183 patients who underwent IM-SLNB successfully had the average time duration of 7 min and the median IMSLN number of 2. There were 87 positive IMSLNs in all the 347 removed IMSLNs, which were mainly concentrated in the second (50.6%) and third (34.5%) intercostal space. The IMSLN metastasis rate was 39.8% (initial surgery) and 13.3% (NST), respectively. All of the 183 IM-SLNB patients received more accurate nodal staging, 57 of whom had stage elevated, which might have prompted modifications to the therapeutic strategy.

CONCLUSIONS

IM-SLNB should be routinely performed in clinically ALN-positive patients, and thus more accurate nodal staging and perfect pathologic complete response definition could be put forward. The identification of IMLN metastases by IM-SLNB might potentially influence therapeutic strategies.

Infiltration tendency of internal mammary lymph nodes involvement in patients with breast cancer: anatomical characteristics and implications for target delineation

Background

Despite increasing clinical data suggest that internal mammary node (IMN) irradiation would improve local-regional control and overall survival in breast cancer, its role remains controversial due to increased risk of cardiac and pulmonary toxicity. The current study aims to determine the high risk areas of IMN metastases by collecting and analyzing the axial imaging of IMN involvement, in order to optimize IMN delineation for breast cancer.

Methods

Breast cancer patients with IMN involvement were retrospectively identified from single-center database. All available imaging modalities including thoracic CT, breast MRI, ultrasound and PET/CT were used to diagnose IMN metastases. Anatomical characteristics from axial imaging, including distribution of involved ribs and distance from the internal mammary vessels (IMV), were collected for each metastatic IMN. What’s more,the natural infiltration tendency of IMNs from IMV was calculated in this study.

Results

In total, 83 metastatic IMNs from 70 breast cancer patients (initial diagnosed:34 and recurrence: 36) were located from axial CT image in this study. The second intercostal space was the most likely involved in patients with single(n = 35, 53.0%) and multiple intercostal space (n = 31, 47.0%) involvement. The percentage of including IMN with a 5 mm, 6 mm and 7 mm medial/lateral distance to the IMV were 75.9% (63/83), 89.2.6% (74/83) and 92.3% (77/83) respectively. While in maximal dorsal/ventral distance, nearly 95% of the nodes were encompassed into 6 mm depth to the IMV. Over 65% of IMN adenopathy (32/49,65.3%) were found to have a growth direction close to the sternum. By retrospective reviewing diagnostic reports, MRI demonstrated a high diagnostic performance in diagnosis of IMN disease (90.3%, 28/31), while CT had a higher misdiagnosis rate (22/63, 34.9%). The diagnostic efficiency of IMN could be improved if different methods were combined.

Conclusions

For patients with indications of prophylactic IMN irradiation, a 7 mm medial and 6 mm dorsal distance to the IMV on axial CT would be optimal to cover the clinical volume of IMN; and it would be reasonable to extend clinical tumor volume (CTV) coverage towards sternum for patients with evident IMN disease. Multi-imaging modalities are recommended to improve the diagnostic specificity and sensitivity of IMN metastases.

Nomogram to Predict Internal Mammary Lymph Nodes Metastasis in Patients With Breast Cancer

Background: Numerous studies have showed that internal mammary lymph node (IMLN) metastasis is an important adverse prognostic factor in patients with breast cancer (BC), however, there are no available prediction model for the preoperative diagnosis of IMLN metastasis.

Methods: Data from 102 breast cancer patients treated with IMLN operation were used to establish and calibrate a nomogram for IMLN status based on multivariate logistic regression. Prediction performance of this model was further validated with a second set of 50 patients with BC. Discrimination of the predict model was assessed by the C-index, and calibration assessed by calibration plots. Moreover, we conducted the decision curve analysis (DCA) to evaluate the clinical value of the nomogram. Finally, the survival status of patients in different risk groups based on nomogram were also compared.

Results: The final multivariate regression model included tumor location, lymph vascular invasion (LVI), and pathological axillary lymph node stage (pALN stage). A nomogram was developed as a graphical representation of the model and had good calibration and discrimination in both sets (with C-index of 0.86 and 0.83 for the training and validation set, respectively). Moreover, the DCA showed the clinical usefulness of our constructed nomogram. False negative (FN) in low risk group classified by nomogram (FN-LR-nomogram) did not significantly impact adjuvant treatment decision making, and more importantly, patients with FN-LR-nomogram had recurrence-free survival equivalent to patients with pathologically ture negative in low risk group classified by nomogram (TN-LR-nomogram).

Conclusions: As a non-invasive prediction tool, our nomogram shows favorable predictive accuracy for IMLN metastasis in patients with BC and can serve as a basis to integrate future molecular markers for its clinical application.

Aggressive Surgical Excision of Supraclavicular Lymph Node Did Not Improve the Outcomes of Breast Cancer With Supraclavicular Lymph Node Involvement (KROG 16-14)

INTRODUCTION

The purpose of this study was to evaluate the outcomes of upfront surgery followed by radiation therapy (RT) for ipsilateral supraclavicular (SCN) and/or internal mammary (IMN) node-positive breast cancer.

MATERIALS AND METHODS

One hundred fifty-eight patients were included; among these, 91 patients were SCN-positive, 54 were IMN-positive, and 13 were SCN- and IMN-positive. Patients underwent breast conserving surgery (n = 74) or mastectomy (n = 84) followed by systemic therapy, and adjuvant RT to whole breast/chest wall with or without regional nodal RT. Regarding regional treatments for SCN and IMN, SCN excision was performed in 59 (37.3%) patients, IMN excision in 10 (6.3%) patients, SCN RT in 143 (90.5%) patients, and IMN RT in 68 (43.0%) patients.

RESULTS

The median duration of follow-up was 72 months (range, 7-182 months). There were 20 locoregional recurrences and 45 distant metastases. In-field failure was observed only in SCN (n = 8), and 6 of these patients initially underwent SCN excision. The 5-year locoregional recurrence-free survival, disease-free survival (DFS), and overall survival rates were 87.3%, 71.6%, and 89.7%, respectively. Neither SCN excision nor SCN RT dose ≥ 54 Gy improved locoregional control (P = .927 and P = .693, respectively) or DFS (P = .394 and P = .686, respectively). Having ≥ 10 involved axillary lymph nodes was the only independent prognosticator for DFS after adjusting for covariates (P = .003).

CONCLUSION

Regional control rate in initially involved SCN and/or IMN was acceptable in patients treated with upfront surgery followed by systemic therapy plus adjuvant RT. More aggressive regional therapy such as SCN excision did not improve locoregional control or survival.

Incidence of internal mammary node in locally advanced breast cancer and its correlation with metastatic disease: a retrospective observational study

OBJECTIVE

To determine incidence of internal mammary nodes (IMN) at baseline CT of locally advanced breast cancer (LABC) and ascertain prognostic implication.

METHODS AND MATERIALS

Retrospective review of all LABC patients from 1 January 2012 through 31 December 2014 was performed after approval from institutional review board. CTs of 182 patients enrolled were reviewed by two radiologists independently, and IMNs were documented based on size, location and relation with location of breast primary. 3-year follow-up was analysed and incidence of metastases was calculated as overall incidence, incidence in patients with and without discernible IMN at baseline imaging. Results are presented as numbers and percentages. Differences in metastases of two groups were compared using χ² test. 95% CI was calculated and p < 0.05 was considered significant.

RESULTS

77 of 182 had identifiable IMN (42.3% incidence). Majority of identifiable nodes were on ipsilateral side of primary (incidence 90.90%) with higher incidence in patients with upper-outer quadrant tumours (55.9%). Majority were seen in second intercostal space (44.4%). 36 (19.7%) developed distant metastases within 3 years of therapy. Of these, 21 (27.3%) had IMN as compared with 15 (14.3 %) without IMN on baseline imaging. Patients with identifiable IMN on baseline CT had significantly higher incidence of distant metastases (p = 0.0321).

CONCLUSION

Significant number LABC patients have identifiable IMN on baseline imaging with patients showing IMN on baseline CT showing significantly higher rate of metastatic disease following therapy.

ADVANCES IN KNOWLEDGE

Many LABC patients have identifiable IMNs on baseline imaging which show higher incidence of subsequent metastatic disease.

Should internal mammary lymph node sentinel biopsy be performed in breast cancer: a systematic review and meta-analysis

Purpose

Results from studies of internal mammary lymph node sentinel biopsy are inconsistent.

Methods

A comprehensive literature search was conducted in MEDLINE, EMBASE, Scopus, Cochrane database, and Clinical Trials. Studies reporting the rate of internal mammary lymph node sentinel biopsy (IMN-SLNB) positivity were identified. We performed pooled proportion meta-analysis using random-effects meta-analyses. The correlation of IMN and axillary lymph node (AXN) metastasis was also investigated.

Results

After application of inclusion and exclusion criteria, a total of 18 articles (total number of patients = 2427) were included. The pooled estimate for IMN-SLNB positivity rate was 15% (95% confidence interval (CI) 12–17%). Significant between-study heterogeneity was observed. Our results indicate that axillary lymph node metastasis is a strong predictor of IMN involvement (OR 6.01, 95% CI, 3.49, 10.34).

Conclusion

Internal mammary lymph nodes metastasis might be underestimated. Patients with positive axillary lymph nodes have a higher risk of internal lymph nodes metastasis. As a result, IMN-SLNB might be considered in these patients. Future work needs to be done to assess whether pathological confirmed IMN metastasis can affect patients’ survival.

Radiotherapy for initial clinically positive internal mammary nodes in breast cancer

Purpose

Internal mammary lymph node (IMN) involvement is associated with poor prognosis in breast cancer. This study investigated the treatment outcomes of initial clinically IMN-positive breast cancer patients who received adjuvant radiotherapy (RT), including IMN irradiation, following primary breast surgery.

Materials and Methods

We retrospectively reviewed data of 95 breast cancer patients with clinically detected IMNs at diagnosis treated with surgery and RT between June 2009 and December 2015. Patients received adjuvant RT to the whole breast/chest wall and regional lymph node (axillary, internal mammary, and supraclavicular) areas. Twelve patients received an additional boost to the IMN area.

Results

The median follow-up was 43.2 months (range, 4.5 to 100.5 months). Among 77 patients who received neoadjuvant chemotherapy, 52 (67.5%) showed IMN normalization and 19 (24.6%) showed a partial response to IMN. There were 3 and 24 cases of IMN failure and any recurrence, respectively. The 5-year IMN failure-free survival, disease-free survival (DFS), and overall survival (OS) were 96%, 70%, and 84%, respectively. IMN failure-free survival was significantly affected by resection margin status (97.7% if negative, 87.5% for close or positive margins; p = 0.009). All three patients with IMN failure had initial IMN size ≥1 cm and did not receive IMN boost irradiation. The median age of the three patients was 31 years, and all had hormone receptor-negative tumors.

Conclusion

RT provides excellent IMN control without the support of IMN surgery. Intensity-modulated radiotherapy, including IMN boost for breast cancer patients, is a safe and effective technique for regional lymph node irradiation.

Internal Mammary Chain Sentinel Nodes in Early-Stage Breast Cancer Patients: Toward Selective Removal

BACKGROUND

Removal of internal mammary chain sentinel nodes (IMCSNs) affects prognosis and treatment of breast cancer, and internal mammary chain radiotherapy (IMCRT) can improve survival for selected patients. This study aimed to determine the effect of IMCSN biopsy on recurrence-free survival (RFS) and overall survival (OS) and to identify predictive factors for IMCSN and distant metastasis.

METHODS

Patients with IMCSNs were selected from a prospective database for the period 1999-2007. Lymphoscintigraphy was performed after intratumoral technetium-99 m injection, and all sentinel nodes were removed. Both RFS and OS were calculated for subgroups with tumor-positive, tumor-negative, or non-removed IMCSNs. Predictive factors were identified for tumor-positive IMCSNs and distant metastasis by regression analysis.

RESULTS

For 287 (85%) of 336 patients, IMCSN biopsy was performed, and metastasis was detected in 38 patients (13%). The patients with tumor-positive IMCSNs had poorer OS than the patients with no IMCSN metastasis or non-removed IMCSNs (p = 0.002). These patients also had worse RFS due to distant metastasis (p = 0.002). Axillary metastasis was predictive for tumor-positive IMCSNs (positive predictive value, 38.5%). The predictive factors for distant metastasis were tumor-positive IMCSNs (hazard ratio [HR], 2.5), non-removed IMCSNs (HR, 2.3), tumor diameter greater than 1.5 cm (HR, 3.5), and age older than 65 years (HR, 3.1; reference, < 50 years).

CONCLUSIONS

Patients with IMCSNs have worse survival due to distant metastasis. The clinically relevant predictive factor for distant metastasis is tumor larger than 1.5 cm. According to the authors' current protocol, IMCSN biopsy is performed for patients younger than 70 years who have a tumor larger than 1.5 cm, with the cardiotoxicity of the adjuvant IMCRT weighed against the survival benefit.

Internal mammary lymph nodes radiotherapy of breast cancer in the era of individualized medicine

Inclusion internal mammary lymph nodes as a part of regional nodal irradiation have a potential to reduce local recurrence, distant recurrence, and improve survival in breast cancer. However, the increased risk of cardiac toxicity and lungs injure associated with internal mammary lymph nodes irradiation has drew more and more attention. Estimating risk of metastasis in internal mammary lymph nodes based on axillary lymph nodes metastasis status is not always reliable: low-risk do not always mean negative in internal mammary lymph nodes and high-risk do not always indicate positive in internal mammary lymph nodes. Inaccurate prediction of in internal mammary lymph nodes metastasis might lead to over- or under-treatment of in internal mammary lymph node. Internal mammary sentinel lymph node biopsy is a minimally invasive technique which has a high potential to accurately evaluate the metastasis status in in internal mammary lymph nodes and improve accuracy of nodal staging. This technique might be a useful tool to guide individualized internal mammary lymph nodes irradiation.

Regional Nodal Irradiation After Breast Conserving Surgery for Early HER2-Positive Breast Cancer: Results of a Subanalysis From the ALTTO Trial

Background

Two randomized trials recently demonstrated that regional nodal irradiation (RNI) could reduce the risk of recurrence in early breast cancer; however, these trials were conducted in the pretrastuzumab era. Whether these results are applicable to human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients treated with anti-HER2-targeted therapy is unknown.

Methods

This retrospective analysis was performed on patients with node-positive breast cancer who were enrolled in the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization phase III adjuvant trial and subjected to BCS. The primary objective of the present study was to examine the effect of RNI on disease-free survival (DFS). A multivariable cox regression analysis adjusted for number of positive lymph nodes, tumor size, grade, age, hormone receptors status, presence of macrometastatis, treatment arm, and chemotherapy timing was carried out to investigate the relationship between RNI and DFS.

Results

One thousand six hundred sixty-four HER2-positive breast cancer patients were included, of whom 878 (52.8%) had received RNI to the axillary, supraclavicular, and/or internal mammary lymph nodes. Patients in the RNI group had higher nodal burden and more frequently had tumors larger than 2 cm. At a median follow-up of 4.5 years, DFS was 84.3% in the RNI group and 88.3% in the non-RNI group. No differences in regional recurrence (0.9 % vs 0.6 %) or in overall survival (93.6% vs 95.3%) were observed between the two groups. After adjustment in multivariable analysis, there was no statistically significant association between RNI and DFS (hazard ratio = 0.96, 95% confidence interval = 0.71 to 1.29).

Conclusions

Our analysis did not demonstrate a DFS benefit of RNI in HER2-positive, node-positive patients treated with adjuvant HER2-targeted therapy. The benefit of RNI in HER2-positive breast cancer needs further testing within randomized clinical trials.

Unplanned irradiation of internal mammary lymph nodes in breast cancer

AIMS

To evaluate the incidental dose to the internal mammary chain (IMC) in patients treated with three-dimensional conformal radiotherapy, to estimate the predictors affecting the magnitude of IMC receiving dose and to determine the predictive role of clinical parameters on survival.

MATERIALS AND METHODS

Between 2009 and 2015, 348 patients undergoing RT for breast cancer were retrospectively analyzed. All patients underwent our department's routine procedure for breast cancer. The internal mammary lymph nodes were contoured according to Radiation Therapy Oncology Group (RTOG) concensus. Based on each patient's dose-volume histograms, the mean doses (D _mean) to internal mammary gland were analyzed. Overall survival and disease-free survival were also evaluated.

RESULTS

The median follow-up time was 38 (range 3-80) months. The D _mean to IMC was 32.8 Gy and the dose delivered to IMC showed a greater coverage in modified radical mastectomy (MRM) group compared with breast conserving surgery (34.6 vs 26.7 Gy). The T-stage of tumor and the N-stage of tumor affected the incidental dose to IMC. The tumor size, the number of involved lymph nodes, the percentage of involved lymph nodes, hormonal status, advanced T-stage and advanced N-stage were the prognostic factors that affect survival.

CONCLUSION

The IMC received meaningful incidental irradiation dose when treated with two opposite tangential fields and ipsilateral supraclavicular fossa with a single anterior field. The real effect of incidental dose on survival and the hypothesis about the benefit of incidental irradiation of IMC should be examined in clinical studies.

Is internal mammary nodes irradiation as a part of breast cancer postoperative radiotherapy necessary?

Postoperative radiotherapy plays an important role in the multidisciplinary treatment of breast cancer. However, it remains a controversy whether it is necessary to carry out prophylactic internal mammary nodes irradiation (IMNI). This review will focus on this topic. In our opinion, the total risk of relapse should be considered during the decision-making on IMNI; in particular, IMNI is recommended for high-risk patients whose tumor is located at the central/medial area or in patients with positive axillary lymph nodes.

Outcome of pN0 Triple-Negative Breast Cancer with or without Lymph Node Irradiation: A Single Institution Experience

The optimal management of patients with pathologically node-negative triple-negative breast cancer (pN0 TNBC) remains unclear. We hypothesized that lymph node irradiation (LNI; internal mammary chain/periclavicular irradiation) had an impact on outcomes of pN0 TNBC. A cohort of 126 consecutive patients with pN0 TNBC treated between 2007 and 2010 at a single institute were included. All radiotherapy (breast/chest wall, ±LNI) was delivered adjuvantly, following completion of surgery ± chemotherapy. Tumors were reviewed and histologic features were described. Tissue microarrays were constructed and tumors were assessed by immunohistochemistry using antibodies against ER, PR, HER2, Ki-67, cytokeratins 5/6, 14, epidermal growth factor receptor and androgen receptor. Patients were divided into two groups for statistical analysis: LNI (LNI+) or no LNI (LNI-). We focused on disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS). Fifty-seven and 69 patients received or not LNI, respectively. Median age was 52 (range [25-76]) and 55 (range [29-79]) in LNI+ and LNI- group (p = 0.23). LNI was associated with larger tumors (p = 0.033), central/internal tumors (33 versus 4, p < 0.01) and more chemotherapy (86% versus 59.4% p < 0.01). The median follow-up was 53.5 months. The rate of first regional relapse (associated or not with distant relapse) was low in both groups. There was no difference in 4-year DFS (82.2% versus 89.9%; p = 0.266), MFS (87.0% versus 91.1%; p = 0.286) and OS (85.8% versus 89.9%; p = 0.322) between LNI+ and LNI- group, respectively. In univariate analysis, only clinical size (T >10 mm versus ≤10 mm), histologic size (pT >10 mm versus ≤10 mm) and grade 3 (versus grade 2) were found to be significantly associated with shorter DFS. Omission of LNI in patients with pN0 TNBC does not seem to result in poorer outcome. Further studies are needed to specifically evaluate LNI in pN0 TNBC with histologic grade 3 and/or (p)T >10 mm.

SPECT-CT-Guided Thoracoscopic Biopsy of Sentinel Lymph Nodes in the Internal Mammary Chain in Patients With Breast Cancer: A Pilot Study

OBJECTIVE

The objective of this study was to determine the impact of the use of single-photon emission computed tomography fused with computed tomography (SPECT-CT) on thoracoscopic biopsy of sentinel lymph nodes (SLNs) in the internal mammary chain in patients with breast cancer by evaluating resultant changes in staging and their clinical implications.

METHODS

Between September 2010 and January 2014, we performed lymphoscintigraphy-assisted thoracoscopic biopsy of the internal mammary chain SLN in 20 patients with breast cancer. Single-photon emission computed tomography fused with computed tomography was also used in 13 of these patients. The sentinel nodes were surgically identified with the aid of a gamma probe.

RESULTS

Sentinel lymph nodes were identified surgically in 19 of 20 patients. In the 13 patients in whom SPECT-CT was used, it readily identified SLNs, especially when they were located over an intercostal space. Change of staging occurred in three patients (15%), two of whom accordingly received adjuvant radiotherapy to the internal thoracic chain.

CONCLUSIONS

Compared with lymphoscintigraphy alone, the use of SPECT-CT improves localization of the SLN in the internal mammary chain, allowing more accurate planning of each individual's treatment.

Detection of Internal Mammary Adenopathy in Patients With Breast Cancer by PET/CT and MRI

OBJECTIVE

The purpose of this study was to assess the prevalence of internal mammary node (IMN) adenopathy in patients with breast cancer and compare breast MRI and PET/CT for detection of IMN adenopathy.

MATERIALS AND METHODS

This retrospective study included 90 women who underwent MRI and PET/CT before neoadjuvant chemotherapy for clinical stage IIA through IIIA disease. MRI and PET/CT examinations were read independently by two readers trained in breast imaging and nuclear medicine. All patients underwent follow-up MRI at the end of chemotherapy, and 10 with hypermetabolic IMNs underwent follow-up PET/CT. Histology was not obtained. Women were considered to have IMN adenopathy when nodes seen on MRI or having standardized uptake value (SUV) greater than mediastinal blood pool decreased in either size or SUV (or both) after treatment. Features including lymphovascular invasion, tumor quadrant(s), and axillary adenopathy were compared between presence and absence of IMN adenopathy using Fisher's exact test. Prevalence was determined on the basis of the percentage of patients with IMN adenopathy by either modality. The McNemar test compared the prevalence of IMN adenopathy on MRI to its prevalence on PET/CT.

RESULTS

Prevalence of IMN adenopathy was 16% (14/90) by MRI and 14% (13/90) by PET/CT (p = 0.317). After chemotherapy, IMN adenopathy resolved in 12 of 14 patients (86%). In two patients with poor responses in primary tumors, IMN adenopathy persisted, and both patients developed metastatic disease within 6 months. At 3 years, survival was significantly worse in patients with IMN adenopathy than in those without (85.7% vs 53.3%, respectively; p = 0.009).

CONCLUSION

In women with advanced breast cancer receiving neoadjuvant chemo-therapy, prevalence of IMN adenopathy was 16%, equally detected by breast MRI and PET/CT. Identification of IMN adenopathy may affect treatment and provides prognostic information.

Sentinel lymph node biopsy in breast cancer: a work in progress

The sentinel lymph node biopsy is a safe, accurate operation for the initial staging of breast cancer. Over the last decade, there has been increasing literature supporting its use, and it is now considered a standard of care for the initial evaluation of metastatic spread to the axillary lymph node chain.

Outcome and Medial Presentation of Breast Cancer: European Institute of Oncology Experience

BACKGROUND

No analyses have investigated the prognostic role of medial presentation in breast cancer patients on disease-free survival (DFS) and overall survival according to immunohistochemically-defined subtypes.

PATIENTS AND METHODS

We collected information from the institutional clinical database on consecutive breast cancer patients who underwent conservative surgery at the European Institute of Oncology, Milan, Italy, between 1994 and 2008. We compared the outcomes of patients with medial breast cancer with those of patients with nonmedial tumors observed at the institution during the same period.

RESULTS

Among 7369 evaluable patients, 2254 (24%) had their primary tumors in medial quadrants and 7015 (76%) in other areas. Five-year DFS was 84.7% and 86.6% (P = .008) in patients with medial and nonmedial disease, respectively. In multivariate analysis, medial location was correlated with greater risk of recurrence (hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.11-1.35; P < .0001) and death (HR, 1.27; 95% CI, 1.09-1.49; P = .0028).

CONCLUSION

Medial presentation is an adverse prognostic factor for breast cancer patients.

Radiotherapy of the Lymphatic Pathways in Early Breast Cancer

International guidelines reveal substantial differences regarding indications for regional nodal irradiation (RNI). Recently, several randomized studies provided new insights and these are discussed here. Patients with 1-3 positive nodes seem to profit from RNI compared to whole-breast (WBI) or chest-wall irradiation (CWI) 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 1 meta-analysis. Lymph node irradiation yields comparable tumor control in comparison to axillary lymph node dissection while reducing the rate of lymph edema. Data concerning the impact of 1-2 macroscopically affected sentinel nodes or microscopic metastases on prognosis are equivocal. Recent data suggest that the current restrictive use of RNI should be scrutinized, as the hazard-benefit relation appears to shift towards an improvement of outcome.

Regional Nodal Irradiation in Early-Stage Breast Cancer

BACKGROUND

Most women with breast cancer who undergo breast-conserving surgery receive whole-breast irradiation. We examined whether the addition of regional nodal irradiation to whole-breast irradiation improved outcomes.

METHODS

We randomly assigned women with node-positive or high-risk node-negative breast cancer who were treated with breast-conserving surgery and adjuvant systemic therapy to undergo either whole-breast irradiation plus regional nodal irradiation (including internal mammary, supraclavicular, and axillary lymph nodes) (nodal-irradiation group) or whole-breast irradiation alone (control group). The primary outcome was overall survival. Secondary outcomes were disease-free survival, isolated locoregional disease-free survival, and distant disease-free survival.

RESULTS

Between March 2000 and February 2007, a total of 1832 women were assigned to the nodal-irradiation group or the control group (916 women in each group). The median follow-up was 9.5 years. At the 10-year follow-up, there was no significant between-group difference in survival, with a rate of 82.8% in the nodal-irradiation group and 81.8% in the control group (hazard ratio, 0.91; 95% confidence interval [CI], 0.72 to 1.13; P=0.38). The rates of disease-free survival were 82.0% in the nodal-irradiation group and 77.0% in the control group (hazard ratio, 0.76; 95% CI, 0.61 to 0.94; P=0.01). Patients in the nodal-irradiation group had higher rates of grade 2 or greater acute pneumonitis (1.2% vs. 0.2%, P=0.01) and lymphedema (8.4% vs. 4.5%, P=0.001).

CONCLUSIONS

Among women with node-positive or high-risk node-negative breast cancer, the addition of regional nodal irradiation to whole-breast irradiation did not improve overall survival but reduced the rate of breast-cancer recurrence. (Funded by the Canadian Cancer Society Research Institute and others; MA.20 ClinicalTrials.gov number, NCT00005957.).

Internal Mammary and Medial Supraclavicular Irradiation in Breast Cancer

BACKGROUND

The effect of internal mammary and medial supraclavicular lymph-node irradiation (regional nodal irradiation) added to whole-breast or thoracic-wall irradiation after surgery on survival among women with early-stage breast cancer is unknown.

METHODS

We randomly assigned women who had a centrally or medially located primary tumor, irrespective of axillary involvement, or an externally located tumor with axillary involvement to undergo either whole-breast or thoracic-wall irradiation in addition to regional nodal irradiation (nodal-irradiation group) or whole-breast or thoracic-wall irradiation alone (control group). The primary end point was overall survival. Secondary end points were the rates of disease-free survival, survival free from distant disease, and death from breast cancer.

RESULTS

Between 1996 and 2004, a total of 4004 patients underwent randomization. The majority of patients (76.1%) underwent breast-conserving surgery. After mastectomy, 73.4% of the patients in both groups underwent chest-wall irradiation. Nearly all patients with node-positive disease (99.0%) and 66.3% of patients with node-negative disease received adjuvant systemic treatment. At a median follow-up of 10.9 years, 811 patients had died. At 10 years, overall survival was 82.3% in the nodal-irradiation group and 80.7% in the control group (hazard ratio for death with nodal irradiation, 0.87; 95% confidence interval [CI], 0.76 to 1.00; P=0.06). The rate of disease-free survival was 72.1% in the nodal-irradiation group and 69.1% in the control group (hazard ratio for disease progression or death, 0.89; 95% CI, 0.80 to 1.00; P=0.04), the rate of distant disease-free survival was 78.0% versus 75.0% (hazard ratio, 0.86; 95% CI, 0.76 to 0.98; P=0.02), and breast-cancer mortality was 12.5% versus 14.4% (hazard ratio, 0.82; 95% CI, 0.70 to 0.97; P=0.02). Acute side effects of regional nodal irradiation were modest.

CONCLUSIONS

In patients with early-stage breast cancer, irradiation of the regional nodes had a marginal effect on overall survival. Disease-free survival and distant disease-free survival were improved, and breast-cancer mortality was reduced. (Funded by Fonds Cancer; ClinicalTrials.gov number, NCT00002851.).

Role of FDG PET-CT in evaluation of locoregional nodal disease for initial staging of breast cancer

Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is not indicated or recommended in the initial staging of early breast cancer. Although it is valuable for detecting distant metastasis, providing prognostic information, identifying recurrence and evaluating response to chemotherapy, the role of FDG PET/CT in evaluating locoregional nodal status for initial staging of breast cancer has not yet been well-defined in clinical practice. FDG PET/CT has high specificity but compromised sensitivity for identifying axillary nodal disease in breast cancer. Positive axillary FDG PET/CT is a good predictor of axillary disease and correlates well with sentinel lymph node biopsy (SLNB). FDG PET/CT may help to identify patients with high axillary lymph node burden who could then move directly to axillary lymph node dissection (ALND) and would not require the additional step of SLNB. However, FDG PET/CT cannot replace SLNB or ALND due to unsatisfactory sensitivity. The spatial resolution of PET instruments precludes the detection of small nodal metastases. Although there is still disagreement regarding the management of internal mammary node (IMN) disease in breast cancer, it is known that IMN involvement is of prognostic significance, and IMN metastasis has been associated with higher rates of distant metastasis and lower overall survival rates. Limited clinical observations suggested that FDG PET/CT has advantages over conventional modalities in detecting and uncovering occult extra-axillary especially IMN lesions with upstaging the disease and an impact on the adjuvant management.

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.

Status of sentinel lymph node for breast cancer

Long-awaited results from randomized clinical trials designed to test the validity of sentinel lymph node biopsy (SLNB) as replacement of axillary lymph node dissection (ALND) in management of early breast cancer have recently been published. All the trials conclude SLNB has survival rates comparable to those of ALND (up to 10 years in one study) and conclude SLNB has less morbidity than ALND. All the trials support replacing ALND with SLNB for staging in early breast cancer; all support SLNB as the standard of care for such cancer. The SLNB protocols used in the trials varied, and no consensus that would suggest a standard protocol exists. The results of the trials and of other peer-reviewed research do, however, suggest a framework for including some specific methodologies in accepted practice. This article highlights the overall survival and disease-free survival data as reported from the clinical trials. This article also reviews the status of SLN procedures and the following: male breast cancer, the roles of various imaging modalities (single-photon emission computed tomography/computed tomography, positron emission tomography/computed tomography, and ultrasound), ductal carcinoma in situ, extra-axillary SLNs, SLNB after neoadjuvant chemotherapy, radiation exposure to patients and medical personnel, and a new radiotracer that is the first to label SLNs not by particle trapping but by specific macrophage receptor binding. The proper Current Procedural Terminology (CPT) code for lymphoscintigraphy and SLN localization prior to surgery is 78195.

Impact of identification of internal mammary sentinel lymph node metastasis in breast cancer patients

BACKGROUND

Accurate assessment of the internal mammary (IM) nodal basin can impact prognosis and treatment in breast cancer. The goal of this study was to identify characteristics associated with positive IM sentinel lymph nodes (SLNs) and the impact on adjuvant treatment.

METHODS

Clinically node-negative breast cancer patients who underwent SLN dissection including removal of IM SLNs were identified and medical records were reviewed. Statistical analysis was performed using Fisher's exact test and rank-sum tests with a significance level of 0.05.

RESULTS

IM SLNs were removed in 71 patients, 60 (85 %) had negative IM SLNs, whereas 11 (15 %) had positive IM SLNs. Clinicopathologic characteristics were similar between the groups. The majority of patients in both groups had axillary SLNs removed (95 % in the node-negative group vs. 91 % in the node-positive group). Four patients (36 %) with positive IM SLNs had axillary metastasis; thus, IM nodal metastases were the only nodal metastases in 64 % of patients with positive IM SLNs. The identification of IM metastases altered adjuvant therapy in 5 (45 %) patients with positive IM SLNs.

CONCLUSIONS

Patients with positive IM SLNs have clinicopathologic features similar to those of patients with negative IM SLNs limiting the ability to predict IM nodal metastasis preoperatively. The identification of IM nodal metastases significantly impacts treatment decisions, especially when IM nodes are the only site of nodal metastasis. Removal of IM SLNs should be considered when lymphoscintigraphy reveals IM drainage.