The impact on post-surgical treatment of sentinel lymph node biopsy of internal mammary lymph nodes in patients with breast cancer

Internal Mammary Lymphadenopathy Does Not Impact Oncologic Outcomes in Patients Treated with Neoadjuvant Chemotherapy: Results from the I-SPY2 Clinical Trial

BACKGROUND

Internal mammary lymphadenopathy (IML) plays a role in breast cancer stage and prognosis. We aimed to evaluate method of IML detection, how IML impacts response to neoadjuvant chemotherapy (NAC), and oncologic outcomes.

METHODS

We evaluated patients enrolled in the I-SPY-2 clinical trial from 2010 to 2022. We captured the radiographic method of IML detection (magnetic resonance imaging [MRI], positron emission tomography/computed tomography [PET/CT], or both) and compared patients with IML with those without. Rates of locoregional recurrence (LRR), distant recurrence (DR) and event-free survival (EFS) were compared by bivariate analysis.

RESULTS

Of 2095 patients, 198 (9.5%) had IML reported on pretreatment imaging. The method of IML detection was 154 (77.8%) MRI only, 11 (5.6%) PET/CT only, and 33 (16.7%) both. Factors associated with IML were younger age (p = 0.001), larger tumors (p < 0.001), and higher tumor grade (p = 0.027). Pathologic complete response (pCR) was slightly higher in the IML group (41.4% vs. 34.0%; p = 0.03). There was no difference in breast or axillary surgery (p = 0.41 and p = 0.16), however IML patients were more likely to undergo radiation (68.2% vs. 54.1%; p < 0.001). With a median follow up of 3.72 years (range 0.4-10.2), there was no difference between IM+ versus IM- in LRR (5.6% vs. 3.8%; p = 0.25), DR (9.1% vs. 7.9%; p = 0.58), or EFS (61.6% vs. 57.2%; p = 0.48). This was true for patients with and without pCR.

CONCLUSIONS

In this large cohort of patients treated with NAC, outcomes were not negatively impacted by IML. We demonstrated that IML influences treatment selection but is not a poor prognostic indicator when treated with modern NAC and multidisciplinary disease management.

The Incidence of Breast Cancer Lymph Node Involvement in Trinidad and Tobago

Objective This study aims to investigate breast cancer lymph node involvement in a West Indian population while correlating it with various histological parameters and evaluating the role of the sentinel lymph node biopsy. Method This is a retrospective study where histology reports for all breast cancer-related biopsies from 2018 to 2021, totaling 813 samples, were obtained. Histological parameters from these reports were extracted into a spreadsheet and analyzed using Statistical Product and Service Solutions (SPSS, version 28.0; IBM SPSS Statistics for Windows, Armonk, NY) software for TNM staging and axillary and sentinel lymph node dissections, among other fields found in histology reports. Results In 44.8% of cases, patients present at the T2 stage with associated lymph node spread. Each T stage had more lymph nodes involved than uninvolved for tumors sized T2 and higher. Inversely, for tumors staged under T2, there were generally more uninvolved lymph nodes than involved ones. Larger tumors were found to have advanced N staging, especially in the T3 category, where a significantly higher proportion of cases were found to have N2 and N3 staging compared to the other T stages. This trend is also seen in M staging, where larger tumors metastasize more than smaller tumors (40% for T4a, 0% for T1). Despite significant lymph node involvement being observed, sentinel lymph node biopsies were usually negative. Conclusion More patients in this population present with lymph node involvement than without. Larger breast cancer tumors are associated with greater lymph node involvement, particularly at T2 and higher stages. Sentinel lymph node biopsies can be omitted in smaller breast cancer tumors up to 2 cm in size, and the local recurrence rate is low despite a false-negative rate of around 10% in upfront sentinel lymph node biopsy.

Internal mammary lymphadenopathy in breast cancer: a narrative review and update

Background and Objective

While the axillary nodal basin is the most common lymphatic drainage pathway of the breast, the internal mammary (IM) lymph node chain plays a significant role in breast cancer staging and treatment. It has been identified as sentinel nodal drainage in approximately 13-37% of patients. Despite this, the data is still limited with regard to diagnosis and management when there is suspicion or confirmation of IM lymph node (IMLN) involvement by metastatic breast cancer. The objective of this publication is to provide a comprehensive assessment of the current body of literature surrounding the diagnosis, management and prognostic value of IMLNs in breast cancer treatment.

Methods

Review of the literature published regarding IMLN diagnosis, significance, and management was completed in PubMed. Additional focus was placed on reviewing articles published within the past 10 years as foundation for an update regarding the current practice and future directions in this space.

Key Content and Findings

Improved imaging techniques, with positron emission tomography-computed tomography and magnetic resonance imaging, have led to increase in the identification of IM lymphadenopathy, yielding surgical staging of the IM nodes nearly obsolete. While IM nodal metastases may play a role in overall survival (OS), it has not been demonstrated to be an independent risk factor for increased locoregional recurrence. IM nodal irradiation (IMNI) therapy has been a mainstay in the treatment of IM disease in the context of breast cancer. IMNI has demonstrated improvement in OS and risk of distant recurrence. Wide variations in radiation practices for patients with IM lymphadenopathy exist internationally, highlighting the lack of clear data driven consensus guidelines.

Conclusions

Herein, we provide an updated assessment of the current diagnosis, clinical significance, and management of IM lymphadenopathy for breast cancer patients.

Assessing internal mammary lymph node metastasis by breast magnetic resonance imaging in breast cancer

The internal mammary lymph nodes (IMLNs) are a main pathway of metastasis in breast cancer, and breast magnetic resonance imaging (MRI) plays an important role in staging that disease. We investigated the MRI parameters that can predict metastatic IMLNs and evaluated their diagnostic performance by comparing the breast MRI findings for metastatic and benign IMLNs. From January 2016 to December 2020, 474 cases of enlarged IMLNs on breast MRI were identified. By cytopathology or integrated positron emission tomography/computed tomography (PET/CT), 168 IMLNs were confirmed as metastatic, and 81 were confirmed as benign. Breast MRIs were reviewed by 2 radiologists, and various parameters (node axes, fatty hilum, necrosis, margin characteristics, restricted diffusion, and involved levels; primary tumor location and skin involvement) were assessed. Independent t-tests, receiver operating characteristic (ROC) curve analyses, chi-square tests, and Fisher exact tests were performed to compare and evaluate the diagnostic accuracy of the imaging findings. Significant differences in the breast MRI findings for the short and long axes, fatty hilum, necrosis, margin characteristics, diffusion restriction, and tumor location were observed between benign and metastatic IMLNs. Compared with the long axis and the ratio of the axes, the short axis had the best diagnostic value (higher area under the ROC curve) for predicting metastatic IMLNs. In conclusion, breast MRI parameters such as short axis, presence of fatty hilum, necrosis, margin characteristics, and diffusion restriction can be used to evaluate and differentiate benign from metastatic IMLNs, offering valuable insights to improve diagnosis and treatment planning in breast cancer.

Internal mammary lymph node metastasis in breast cancer patients based on anatomical imaging and functional imaging

Internal mammary lymph node (IMLN) metastasis forms part of the clinical node classification for primary breast cancer, which influences the treatment strategy. However, because of the IMLNs' complicated anatomical structures and relationships with adjacent structures, IMLN biopsy or resection is associated with a limited improvement in prognosis and a high complication rate. The positivity rate also varies broadly according to imaging modality, and there is a low rate of agreement between the imaging and pathological diagnoses, which creates imprecision in the preoperative staging. The IMLN positivity rate also varies remarkably, and there are no clear, accurate, and non-invasive modalities for diagnosing the pre-mastectomy IMLN status. Nevertheless, medical imaging modalities continue to evolve, with functional imaging and image-guided thoracoscopic biopsy of sentinel IMLNs being well established. Thus, personalized decision-making and treatment selection should be based on the modality-specific differences in the diagnosis of IMLN metastasis/recurrence and the patient's specific risk factors.

Evaluation of internal mammary lymph node biopsy during microsurgical breast reconstruction: An analysis of 230 consecutive patients

INTRODUCTION

Clinical significance of internal mammary (IM) lymph node biopsy during microvascular free flap breast reconstruction remains controversial. Some microsurgeons may choose to biopsy an IM lymph node during routine IM vessel dissection. The authors reviewed the results of IM lymph node biopsy during autologous breast reconstruction.

METHODS

A retrospective chart review of patients who underwent autologous breast reconstruction during a seven-year period (January 2010 to January 2017) was performed. Patient demographic data, disease staging, flap details, pathology reports, and adjuvant treatment were evaluated.

RESULTS

A total of 230 patients with a mean age of 52.1 (SD 9.3) underwent IM lymph node biopsy (n = 297). Single IM lymph node was removed in 169 patients, 2 nodes were removed in 56 patients, 3 nodes in 4 patients, and 4 nodes in a single patient. Histopathologic analysis demonstrated presence of IM lymph node metastasis in 16 patients (7.0%). Thirteen patients were found to have metastatic IM lymph nodes in the setting of immediate reconstruction. Three patients were found to have metastatic IM lymph nodes in the setting of delayed. Five out of 16 patients (31.3%) had negative axillary sentinel lymph node biopsy and IM lymph nodes were the only site of nodal metastases. All five of these patients were upstaged accordingly and received adjuvant therapy based on the discussion at the multidisciplinary breast tumor conference.

CONCLUSIONS

Opportunistic internal mammary lymph node sampling during autologous breast reconstruction can be performed with minimal morbidity and has significant impact on the disease staging and adjuvant treatment.

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.

Implications of Internal Mammary Lymph Node Sampling During Microsurgical Breast Reconstruction

INTRODUCTION

Internal mammary lymph node (IMN) chain assessment for breast cancer is controversial; however, current oncologic data have shed new light on its importance. Metastatic involvement of the IMN chain has implications for staging, prognosis, treatment, and survival. Here, we analyzed our data gathered during sampling of the IMN and the oncologic treatment changes that resulted from our findings.

METHODS

A retrospective chart review was performed on 581 patients who underwent free-flap breast reconstruction performed by the senior author. All dissected IMNs were submitted for pathological examination. Patient demographics, oncologic data, and the results of IMN sampling were reviewed.

RESULTS

581 patients undergoing 981 free flaps were identified. A total of 400 lymph node basins were harvested from 273 patients. Of these, nine had positive IMNs. Two of these nine patients had positive IMNs of the contralateral nonaffected breast. Five patients had positive axillary lymph nodes. Four patients had multifocal tumors, one of which was bilateral. Seven patients had an increase in cancer stage as a result of having positive IMNs. Six patients had a change in treatment: two patients required additional chemotherapy, one received adjuvant radiation therapy, and three necessitated both supplemental chemotherapy and radiation.

CONCLUSIONS

Opportunistic biopsy of the IMN while dissecting the recipient vessels is simple and results in no added morbidity. We recommend that biopsy of the IMN chain be performed whenever internal mammary vessels are dissected for microsurgical anastomosis in breast cancer patients. Positive IMN involvement should encourage thorough oncological workup and treatment reevaluation.

LEVEL OF EVIDENCE IV

Case series.

Internal Mammary Lymph Node Biopsy During Free-Flap Breast Reconstruction: Optimizing Adjuvant Breast Cancer Treatment Through Comprehensive Staging

BACKGROUND

Accurate breast cancer staging is essential for optimal management of adjuvant therapies. While breast lymphatic drainage involves both axillary and internal mammary (IM) lymph node (LN) basins, IM LN sampling is not routinely advocated. The current study analyzes the incidence of IM LN metastases sampled during free flap breast reconstruction and subsequent changes in adjuvant treatment.

METHODS

A retrospective analysis of patients with positive IM LN biopsies during free flap breast reconstruction was performed. Pre-reconstruction surgical and adjuvant therapies as well as staging and prognostic data were recorded. Change in adjuvant therapies based solely on IM LN positivity was determined.

RESULTS

IM LN metastases were found on 28 (1.3%) out of 2057 patients and comprised the study population. Mean age was 49 years with pre-reconstruction chemotherapy or radiation administered in 50 or 54% of cases, respectively. Five (18%) patients had previously undergone lumpectomy with axillary sampling. Mean tumor size was 3.1 cm with tumor location evenly distributed among all four quadrants. Ten (36%) patients had isolated IM LN metastases Patients with both axillary and IM disease had larger lesions, increased prevalence of pre-reconstruction chemotherapy and radiation. Based exclusively on positive IM LN disease, 17 (63%) patients had a change in adjuvant therapy.

CONCLUSION

Despite the low incidence of IM LN metastases, IM LN biopsy during free flap breast reconstruction is recommended. In 36% of cases, nodal metastases were isolated to the IM nodes. Identification of IM metastases influenced adjuvant therapies in a majority of cases.

Validation study for the hypothesis of internal mammary sentinel lymph node lymphatic drainage in breast cancer

According to axilla sentinel lymph node lymphatic drainage pattern, we hypothesized that internal mammary sentinel lymph node (IM-SLN) receives lymphatic drainage from not only the primary tumor area, but also the entire breast parenchyma. Based on the hypothesis a modified radiotracer injection technique was established and could increase the visualization rate of the IM-SLN significantly. To verify the hypothesis, two kinds of tracers were injected at different sites of breast. The radiotracer was injected with the modified technique, and the fluorescence tracer was injected in the peritumoral intra-parenchyma. The location of IM-SLN was identified by preoperative lymphoscintigraphy and intraoperative gamma probe. Then, internal mammary sentinel lymph node biopsy (IM-SLNB) was performed. The fluorescence status of IM-SLN was identified by the fluorescence imaging system. A total of 216 patients were enrolled from September 2013 to July 2015. The overall visualization rate of IM-SLN was 71.8% (155/216). The success rate of IM-SLNB was 97.3% (145/149). The radiotracer and the fluorescence tracer were identified in the same IM-SLN in 127 cases, the correlation and the agreement is significant (Case-base, r_s=0.836, P<0.001; Kappa=0.823, P<0.001). Different tracers injected into the different sites of the intra-parenchyma reached the same IM-SLN, which demonstrates the hypothesis that IM-SLN receives the lymphatic drainage from not only the primary tumor area but also the entire breast parenchyma.

Robot-assisted internal mammary lymph chain excision for breast cancer: A case report

RATIONALE

Understanding the status of internal mammary lymph nodes of breast cancer is critical in the accurate staging of breast cancer and the development of accurate therapeutic regimen for selected patients. Current techniques for dissection of internal mammary lymph node biopsy involve endoscopic or Traditional thoracic surgery, An important drawback of the current techniques is the great trauma caused by them.

PATIENT CONCERNS

Da Vinci robotic surgery system (Intuitive Surgical Inc. Sunnyvale, CA) was used to perform the internal mammary lymph chain excision for a breast cancer patient with left internal mammary lymph node metastasis.

DIAGNOSES

Positron emission tomography-computed tomography examination and Ultrasonography examination.

INTERVENTIONS

In this paper, we introduce a Robot-assisted technique for dissection of internal mammary lymph node biopsy with only 3 small trocar ports. This technique reduces the incision size and considerably reduce the trauma.

OUTCOMES

The operation lasted a duration of 1.5 hours. The operation was carried out smoothly with removal of 9 internal mammary lymph nodes in total. The amount of intra operative bleeding was less than 10 ml. The patient's postoperative recovery was fast. 11-month postoperative follow-up showed that the patient recovered well after surgery, no local recurrence or distant metastasis was found, and no obvious discomfort was reported.

LESSONS

Robot-assisted excision of internal mammary lymph chain in breast cancer is a safe, effective and simple operation with minimal invasion.

Sentinel lymph node biopsy in breast cancer: a technical and clinical appraisal

Breast cancer is the most common type of cancer diagnosed in women worldwide. Regional lymph node status is one of the strongest predictors of long-term prognosis in primary breast cancer. Sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection as the standard surgical procedure for staging clinically tumor-free regional nodes in patients with early-stage breast cancer. SLNB staging considerably reduces surgical morbidity in terms of shoulder dysfunction and lymphedema, without affecting diagnostic accuracy and prognostic information. Clinicians should not recommend axillary lymph node dissection for women with early-stage breast cancer who have tumor-free findings on SLNB because there is no advantage in terms of overall survival and disease-free survival. Starting from the early 1990s, SLNB has increasingly been used in breast cancer management, but its role is still debated under many clinical circumstances. Moreover, there is still a lack of standardization of the basic technical details of the procedure that is likely to be responsible for the variability found in the false-negative rate of the procedure (5.5-16.7%). In this article, we report the aspects of SLNB that are well established, those that are still debated, and the advancements that have taken place over the last 20 years. We have provided an update on the methodology from both a technical and a clinical point of view in the light of the most recent publications.

Initial Fludeoxyglucose (18F) Positron Emission Tomography-Computed Tomography (FDG-PET/CT) Imaging of Breast Cancer - Correlations with the Primary Tumour and Locoregional Metastases

BACKROUND

We aimed to evaluate initial PET/CT features of primary tumour and locoregional metastatic lymph nodes (LNs) in breast cancer and to look for potential relationships between several parameters from PET/CT.

MATERIAL/METHODS

Twenty-three women (mean age; 48.66±12.23 years) with a diagnosis of primary invasive ductal carcinoma were included. They underwent PET/CT imaging for the initial tumour staging and had no evidence of distant metastates. Patients were divided into two groups. The LABC (locally advanced breast cancer) group included 17 patients with ipsilateral axillary lymph node (LN) metastases. The Non-LABC group consisted of six patients without LN metastases. PET/CT parameters including tumour size, axillary LN size, SUV_max of ipsilateral axillary LNs (SUV_max-LN), SUV_max of primary tumour (SUV_max-T) and NT ratios (SUV_max-LN/SUV_max-T) were compared between the groups. Correlations between the above-mentioned PET/CT parameters in the LABC group as well as the correlation between tumour size and SUV_max-T within each group were evaluated statistically.

RESULTS

The mean values of the initial PET/CT parameters in the LABC group were significantly higher than those of the non-LABC group (p<0.05). The correlation between tumour size and SUV_max-T value within both LABC and non-LABC groups was statistically significant (p<0.05). In the LABC group, the correlations between the size and SUV_max-LN values of metastatic axillary LNs, between tumour size and metastatic axillary LN size, between SUV_max-T values and metastatic axillary LN size, between SUV_max-T and SUV_max-LN values, and between tumour size and SUV_max-LN values were all significant (p<0.05).

CONCLUSIONS

We found significant correlations between PET/CT parameters of the primary tumour and those of metastatic axillary LNs. Patients with LN metastases had relatively larger primary tumours and higher SUV_max values.

Sentinel Lymph Node Biopsy in Breast Cancer: Indications, Contraindications, and Controversies

Axillary lymph node status, a major prognostic factor in early-stage breast cancer, provides information important for individualized surgical treatment. Because imaging techniques have limited sensitivity to detect metastasis in axillary lymph nodes, the axilla must be explored surgically. The histology of all resected nodes at the time of axillary lymph node dissection (ALND) has traditionally been regarded as the most accurate method for assessing metastatic spread of disease to the locoregional lymph nodes. However, ALND may result in lymphedema, nerve injury, shoulder dysfunction, and other short-term and long-term complications limiting functionality and reducing quality of life. Sentinel lymph node biopsy (SLNB) is a less invasive method of assessing nodal involvement. The concept of SLNB is based on the notion that tumors drain in an orderly manner through the lymphatic system. Therefore, the SLN is the first to be affected by metastasis if the tumor has spread, and a tumor-free SLN makes it highly unlikely for other nodes to be affected. Sentinel lymph node biopsy has become the standard of care for primary treatment of early breast cancer and has replaced ALND to stage clinically node-negative patients, thus reducing ALND-associated morbidity. More than 20 years after its introduction, there are still aspects concerning SLNB and ALND that are currently debated. Moreover, SLNB remains an unstandardized procedure surrounded by many unresolved controversies concerning the technique itself. In this article, we review the main indications, contraindications, and controversies of SLNB in breast cancer in the light of the most recent publications.

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.

Internal Mammary Sentinel Lymph Node Biopsy With Modified Injection Technique: High Visualization Rate and Accurate Staging

Although the 2009 American Joint Committee on Cancer incorporated the internal mammary sentinel lymph node biopsy (IM-SLNB) concept, there has been little change in surgical practice patterns because of the low visualization rate of internal mammary sentinel lymph nodes (IMSLN) with the traditional radiotracer injection technique. In this study, various injection techniques were evaluated in term of the IMSLN visualization rate, and the impact of IM-SLNB on the diagnostic and prognostic value were analyzed.Clinically, axillary lymph nodes (ALN) negative patients (n = 407) were divided into group A (traditional peritumoral intraparenchymal injection) and group B (modified periareolar intraparenchymal injection). Group B was then separated into group B1 (low volume) and group B2 (high volume) according to the injection volume. Clinically, ALN-positive patients (n = 63) were managed as group B2. Internal mammary sentinel lymph node biopsy was performed for patients with IMSLN visualized.The IMSLN visualization rate was significantly higher in group B than that in group A (71.1% versus 15.5%, P < 0.001), whereas the axillary sentinel lymph nodes were reliably identified in both groups (98.9% versus 98.3%, P = 0.712). With high injection volume, group B2 was found to have higher IMSLN visualization rate than group B1 (75.1% versus 45.8%, P < 0.001). The IMSLN metastasis rate was only 8.1% (12/149) in clinically ALN-negative patients with successful IM-SLNB, and adjuvant treatment was altered in a small proportion. The IMSLN visualization rate was 69.8% (44/63) in clinically ALN-positive patients with the IMSLN metastasis rate up to 20.5% (9/44), and individual radiotherapy strategy could be guided with the IM-SLNB results.The modified injection technique (periareolar intraparenchymal, high volume, and ultrasound guidance) significantly improved the IMSLN visualization rate, making the routine IM-SLNB possible in daily practice. Internal mammary sentinel lymph node biopsy could provide individual minimally invasive staging, prognosis, and decision making of the internal mammary radiotherapy, especially for clinically ALN-positive patients.

Regional recurrence in the era of sentinel lymph node biopsy

BACKGROUND

The incidence of all-location regional recurrence after sentinel lymph node biopsy is not well documented. This study attempts to identify risk factors.

METHODS

A prospectively maintained database was queried to identify patients with a regional recurrence of breast cancer after a first operation for invasive unilateral breast cancer. Patients with regional recurrence were compared with those alive and disease free at 5 years.

RESULTS

Twenty-one of 1,060 patients (2%) experienced a regional recurrence. Most patients (95%) underwent sentinel lymph node biopsy as their axillary staging. Those with regional recurrences had larger tumors (P < .001), higher stage disease (P < .001), more estrogen receptor- and triple-negative breast cancers (P < .001), and more positive lymph nodes (P = .007). Mastectomy (P = .001) and receipt of neoadjuvant and/or chemotherapy (P < .001) were more common among those with regional recurrences.

CONCLUSIONS

Regional recurrence of breast cancer occurs infrequently. Risk factors include high-risk cancers, higher stage at presentation, nodal involvement, and need for therapies reflecting higher risk biology.

Role of SPECT-CT in breast cancer sentinel node biopsy when internal mammary chain drainage is observed

INTRODUCTION

SPECT-CT in the detection of the sentinel lymph node (SLN) of breast cancer offers known advantages over conventional planar lymphoscintigraphy. Sometimes, it shows atypical findings like mediastinal lymphatic drainage. We have evaluated these atypical findings showed by SPECT-CT performed in patients with migration to the internal mammary chain (IMC) and their roles in the management of the patients.

MATERIALS AND METHODS

We reviewed the 56 lymphoscintigraphies (planar and SPECT-CT) of 56 women (average age: 55 years) diagnosed with breast cancer with IMC migration observed in the planar images. We compared the two techniques, obtaining the number of depicted nodes, atypical locations, their exact anatomical location and their role in the management of the patient.

RESULTS

Planar images showed a total number of 81 IMC nodes. SPECT-CT showed 74 nodes in the IMC territory and 14 mediastinal lymphatic nodes in 6 patients. Out of the 81 IMC nodes reported by planar images, seven corresponded to mediastinal nodes. Planar and hybrid images showed 110 and 130 axillary nodes, respectively. SPECT-CT showed additional findings in five patients: three infraclavicular and two supraclavicular nodes that were exactly located. One intramammary node was discarded by the SPECT-CT as a focal skin contamination.

CONCLUSION

Mediastinal nodes are unexpected, but not uncommon findings that are important in the planning of SLN biopsy. SPECT-CT found more nodes than planar images, being able to separate mediastinal and IMC nodes, helping to exactly depict the SLN and its relations with anatomical structures.

Prognostic Significance of Tumor-Positive Internal Mammary Sentinel Lymph Nodes in Breast Cancer: A Multicenter Cohort Study

INTRODUCTION

The introduction of the sentinel lymph node biopsy (SLNB) in breast cancer has renewed interest in lymphatic drainage to the internal mammary (IM) nodes. The clinical impact of tumor positive IM nodes is not completely clear. This study evaluated the incidence and impact on overall survival of metastatic IM SLNs.

METHODS

Between 1997 and 2010, 3685 patients underwent surgery including SLNB for primary breast cancer following an intratumoral or peritumoral radioactive-tracer injection. The presence of lymph node metastases was categorized according to the TNM-classification. Cumulative overall survival was estimated and the influence of metastases in the IM nodes and other factors was assessed by Cox-regression-analysis.

RESULTS

In 754 patients (20.5 %) ipsilateral IM lymph nodes were visualized on preoperative lymphoscintigraphy, retrieval rate of IM SLNs was 81.0 %. IM metastases were detected in 130 patients (21.3 % of retrieved SLNs and 3.5 % of all patients respectively). The presence of IM metastases was associated with axillary metastases (p < 0.001). After a median follow-up of 61.2 months, 10.9 % of patients had died. In a multivariate analysis IM metastases did not have a significant effect on overall survival [HR] 1.20; CI: 0.73-1.98. In patients without axillary metastases (n = 2398), the presence of IM metastases (n = 43) was associated with worse survival [HR] 2.68; 95 % CI: 1.30-5.54.

CONCLUSION

Overall, the presence of IM metastases did not effect overall survival independent of other prognostic factors including axillary metastases. However, the small subgroup of patients who had IM metastases alone had worse outcome than patients without any regional lymph node metastases.

Breast cancer patient with an uncommon lymphatic drainage evidenced by SPECT/CT

SPECT/CT reinforces the role of lymphoscintigraphy in breast cancer by solving some cases with difficult reading on planar scintigraphy. An 80-year-old woman was referred to our institution for management of a screen-detected, nonpalpable, invasive lobular carcinoma of lower inner quadrant of the left breast. Lymphoscintigraphy was performed before surgery. Planar images showed an axillary sentinel node and 2 medially located hot spots. SPECT/CT allowed determining that one of the extra-axillary drainage sites was to the internal mammary basin, while the second corresponded to a mediastinal lymph node. Although this drainage was unexpected, mediastinum is a common site of breast cancer recurrence.

Lymphoscintigraphy with peritumoral injection versus lymphoscintigraphy with subdermal periareolar injection of technetium-labeled human albumin to identify sentinel lymph nodes in breast cancer patients

BACKGROUND

Preoperative lymphoscintigraphy is without doubt a valid method for the detection of the sentinel lymph node (SLN). There has been considerable debate regarding the optimal site for the introduction of the tracer; various sites include peritumoral (PT), periareolar (PA), subdermal, and intradermal injection.

PURPOSE

To evaluate retrospectively the lymphoscintigraphic identification rate of peritumoral (PT) injection versus subdermal periareolar (PA) injection in the detection of SLNs in breast cancer.

MATERIAL AND METHODS

Between October 2002 and December 2011, a cohort of 906 consecutive patients with biopsy proven breast cancer underwent 914 SLN biopsy procedures. A total of 339 procedures (Group A) were performed using a PT deep injection of radiotracer while 575 procedures (Group B) adopted a subdermal PA injection of radiotracer towards the upper outer quadrant, regardless of the site of the carcinoma. All the patients underwent synchronous excision of the breast cancer and SLN biopsy.

RESULTS

SLNs were identified in the lymphoscintigram in 308/339 cases (90.85%) of Group A (PT injection) and in 537/575 cases (93.39%) of Group B (PA injection). Furthermore, in 2/339 patients (0.58%) of Group A, internal mammary lymph nodes were found at lymphoscintigraphy, whereas no internal mammary sentinel nodes were found in the Group B patients. The intraoperative identification rate of axillary SLNs was 99.41% (337 of 339) in the Group A patients and 99.65% (573 of 575) in the Group B patients. There was no significant difference in the two groups between the incidence of the number of SLNs detected and the incidence of identification of positive SLNs.

CONCLUSION

PT versus PA injection of radiotracer showed comparable success rates for axillary SLN identification, and can be considered a rapid and reliable method.

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.

A meta-analysis of internal mammary lymph node metastasis in breast cancer patients

BACKGROUND

Knowing the status of the internal mammary lymph (IML) nodes is important for accurate staging and appropriate selection of subsequent treatment in breast cancer. We conducted a meta-analysis to clarify the rate of IML node metastasis in breast cancer patients and discussed the importance of this finding.

METHODS

We retrieved articles from the literature that reported positive rates of IML node metastasis in breast cancer patients. The quality of the selected articles was assessed using the 'Methodological Index for Non-Randomized Studies'. The heterogeneity was tested, and publication bias was assessed using a funnel plot. Finally, the positive rate of IML node metastasis in breast cancer patients was calculated using the random-effects model.

RESULTS

15 articles met the inclusion criteria and a total of 4,248 patients were included in the analysis. Heterogeneity across the studies was statistically significant (p = 0.014); thus, the random-effects model was used and the calculated positive rate of IML node metastasis was 23% (95% confidence interval (CI), 0.21-0.25).

CONCLUSIONS

Approximately 23% of the breast cancer patients had IML node metastases, for which the prognosis is generally poor. Accurate staging and integrated treatment are necessary to improve the survival of these patients.

Internal Mammary Sentinel Node Biopsy in Breast Cancer. Is it Indicated?

Axillary sentinel node (A-SN) biopsy is a standard procedure in breast cancer surgery. Sampling of intenal mammary sentinel nodes (IM-SN) is not performed routinly, although it is also considered an important prognostic factor of breast cancer. The role of this latter procedure was investigated in cases of IM-SN visualized on lymphoscintigraphy. Between January 2001 and June 2012 1542 patients with clinically node negative operable primary breast cancer had sentinel node biopsy (SNB). Both axillary and IM-SN were sampled (whenever detected), based on lymphoscintigraphy, intraoperative gamma probe detection and blu dye mapping. Lymphoscintigraphy showed IM-SN in 83 cases. IM-SN biopsy (IM-SNB) was succesfull in 77 patients (93%). A total of 86 IM-SNs were removed. IM-SN involvement was identified in 14 cases, representing 18% of patients who underwent IM-SNB. This included macrometastases (MAC) in 5 cases, micrometastases (MIC) in 2 cases, isolated tumor cells (ITC) in 7 cases. No significant differences were found between patients with and without IM-SN involvement in terms of age, tumor location, tumor size, axillary involvement, tumor grade or estrogen receptor status. The IM-SN involvement has lead to new therapeutic indications in 2 cases (2.6%), both of them due to MAC in the IM-SN: in 1 case change in chemotherapy and in 1 case change in radiotherapy, with the addition of iradiation of the internal mammary chain. Based on this series and information from the literature, we conclude that the indication for an IM-SNB procedure is very limited and its routine use should not be recommended.

(18)F-FDG PET/CT-positive internal mammary lymph nodes: pathologic correlation by ultrasound-guided fine-needle aspiration and assessment of associated risk factors

OBJECTIVE

Metastatic breast cancer in internal mammary (IM) lymph nodes is associated with a poor prognosis. This study correlates (18)F-FDG PET/CT-positive IM lymph nodes with ultrasound-guided fine-needle aspiration (FNA) cytopathologic results and determines risk factors for IM node positivity on PET/CT.

MATERIALS AND METHODS

For this retrospective study, a database search was performed to identify patients referred for whole-body (18)F-FDG PET/CT for initial staging or restaging of breast cancer from January 1, 2005, through December 31, 2010. The radiology reports and images were reviewed for patients with (18)F-FDG-avid IM lymph nodes on PET/ CT and correlated with the cytopathologic results from FNA of selected PET/CT-positive IM lymph nodes. The patients with positive IM nodes on PET/CT who underwent PET/CT for initial staging were compared against age-matched and tumor size-matched patients to identify risk factors for IM node positivity on PET/CT.

RESULTS

One hundred ten of 1259 patients (9%) had an (18)F-FDG-avid IM lymph node on PET/CT. Twenty-five patients underwent ultrasound-guided FNA of a suspicious IM node, and 20 IM lymph nodes (80%) were cytologically proven metastases from the primary breast malignancy. High tumor grade, the presence of lymphovascular invasion (LVI), and triple receptor-negative hormonal receptor status were found to be significant risk factors for IM node positivity on PET/CT (p < 0.05).

CONCLUSION

Although fewer than 10% of breast cancer patients have positive IM nodes on (18)F-FDG PET/CT performed for initial staging or restaging, a positive IM node indicates a very high likelihood of malignant involvement on ultrasound-guided FNA. The presences of high tumor grade, LVI, or triple receptor-negative status are risk factors for IM node positivity on (18)F-FDG PET/CT.

Predictive factors of isolated tumor cells and micrometastases in axillary lymph nodes in breast cancer

INTRODUCTION

Since the introduction of the sentinel lymph node biopsy (SLNB) in patients with breast cancer, micrometastases and isolated tumor cells are detected frequently in the SLN. As such, they offer an opportunity to study the development of regional metastases in breast cancer.

PATIENTS AND METHODS

Between June 1999 and November 2010 1418 patients with cT1-2N0 breast cancer underwent SLNB. Primary tumor characteristics and information regarding regional lymph node involvement were collected prospectively. Patients were categorized into four levels of lymph node involvement: pN0, pN0(i+), pN1mi and pN ≥ 1a. An univariate analysis and a binary logistic regression analysis were performed to assess the relation between patient- and tumor characteristics and lymph node involvement.

RESULTS

Increasing tumor size and younger age were associated with a higher risk of pN1mi and pN ≥ 1a and a lower chance of pN0 and pN0(i+). Triple negative molecular subtype was associated with a decreased risk of pN1mi and pN ≥ 1a. Tumor size was positively related to overall occurrence of regional lymph node metastases in a linear manner.

CONCLUSION

Patients with larger tumors, no triple negative disease, and younger age showed a decreased chance of both pN0 and pN0(i+) and an increased risk of both pN1mi and pN ≥ 1a. There seems to be a gradual shift in risk pattern from pN0 to pN0(i+) to pN1mi and to pN ≥ 1a-disease. The presence of the smallest metastases remained fairly constant over time when compared to macrometastases. This constant presence suggests that the risk of seeding and outgrowth of metastases remains constant over time.

Breast cancer sentinel node scintigraphy: differences between imaging results 1 and 2 h after injection

INTRODUCTION

Timing of image acquisition in breast cancer sentinel node scintigraphy remains a subject of debate. Therefore, the performance of our protocol in which images are acquired 1 and 2 h after injection was evaluated. The results of sentinel node scintigraphy 1 and 2 h after injection were compared with regard to the sentinel lymph nodes visualized.

METHODS

We studied 132 patients who were consecutively referred for sentinel lymph node biopsy. 99mTc-albumine nanocolloid (120 MBq) was injected peritumourally into patients with palpable tumours and intratumourally into patients with nonpalpable tumours. All scintigraphic images taken for the sentinel node procedure were evaluated. The number of sentinel nodes per anatomic localization and the interpretability of the images were scored.

RESULTS

A total of 132 patients underwent sentinel node scintigraphy 1 h after injection. Of these, 117 patients also underwent sentinel node scintigraphy 2 h after injection. An axillary sentinel node was visualized in 79.5 and 95.7% of patients, respectively, 1 and 2 h after injection. In 20.5% of the patients the images acquired 1 h after injection did not show a sentinel node. Furthermore, in all procedures, the images 1 h after injection were of no added value to those acquired 2 h after injection.

CONCLUSION

Scintigraphic imaging 2 h after a single peritumoural or intratumoural administration of about 120 MBq 99mTc-albumine nanocolloid yields an axillary sentinel node in over 95% of cases. Imaging 1 h after injection is of no additional value and can be omitted.

Sentinel lymph node biopsy of the internal mammary chain in breast cancer

Routine removal of the internal mammary chain (IMC) sentinel node in breast cancer patients remains a subject of discussion. The aim of this study was to determine the impact of routinely performed IMC sentinel node biopsy on the systemic and locoregional treatments plan. All patients with biopsy proven breast cancer who underwent a sentinel node procedure between 2002 and 2011 were included in a prospective database. In cases of IMC drainage, successful exploration of the IMC (i.e., sentinel node removed) and surgical complications were registered. If the removed sentinel node contained malignant cells we determined if this altered the treatment plan when practising the current guidelines. In total, 119 of the 493 included patients showed IMC drainage on lymphoscintigraphy. Exploration of the IMC was performed in 107 (89 %) patients; in 86/107 (80 %) exploration was successful. In 14/107 patients (13 %) the IMC sentinel node was tumor positive. Macro and micro metastases were found in eight and six patients, respectively. In the group of patients who underwent surgical exploration of the IMC, systemic treatment was changed in none, radiotherapy treatment in 13/107 patients (11 %). Routine sentinel node biopsy of the IMC does not alter the systemic treatment. Radiotherapy treatment is altered in a small proportion of the patients; however, solid scientific evidence for this adjustment is lacking.

Impact of internal mammary lymph node drainage identified by preoperative lymphoscintigraphy on outcomes in patients with stage I to III breast cancer

BACKGROUND

Involvement of internal mammary (IM) lymph nodes is associated with a poor prognosis for patients with breast cancer. This study examined the effect of drainage to IM nodes identified by lymphoscintigraphy on oncologic outcomes.

METHODS

A prospectively maintained breast cancer patient database at the University of Texas MD Anderson Cancer Center was used to identify patients with stage I to III breast cancer who underwent preoperative lymphoscintigraphy with peritumoral injection of colloid and intraoperative lymphatic mapping from 1996 to 2005. Medical records were reviewed of 1772 patients who had drainage to any lymph node basin on lymphoscintigraphy but who did not undergo IM nodal biopsy. Patients with IM drainage, with or without axillary drainage, were compared with patients without IM drainage. Local-regional recurrence, distant disease-free survival (DDFS), and overall survival were evaluated.

RESULTS

We identified IM drainage in 334 patients (18.8%). Patients with IM drainage were significantly younger, less likely to have upper outer quadrant tumors, and more likely to have smaller and medial tumors than patients without IM drainage. Rates of IM irradiation did not differ between the 2 groups. The median follow-up time was 7.4 years. On multivariate analysis, IM drainage was significantly associated with a worse DDFS (hazard ratio, 1.6; 95% confidence interval, 1.03-2.6; P = .04) but not local-regional recurrence or overall survival.

CONCLUSIONS

IM drainage on preoperative lymphoscintigraphy was found to be significantly associated with worse DDFS. Further study is needed to determine the role of lymphoscintigraphy in the personalization of breast cancer staging and therapy.

Long-term outcome of internal mammary lymph node detected by lymphoscintigraphy in early breast cancer

Purpose

Internal mammary lymph node (IMLN) metastasis is an important prognostic indicator in breast cancer. However, the necessity of internal mammary sentinel lymph node biopsy for accurate staging, for choosing adjuvant treatment, and as a prognostic indicator, has remained controversial.

Methods

From January 2001 to December 2006, 525 female breast cancer patients underwent radical surgery after preoperative lymphatic scintigraphy. We retrospectively analyzed the follow-up results, recurrences, and deaths of all patients.

Results

There was no significant difference in the clinicopathological characteristics between the axilla and the IMLN groups. The median follow-up period was 118.8 months (range, 7-122 months) in the axilla group and 107.7 months (range, 14-108 months) in the IMLN group. During the median follow-up period, the breast cancer-related death rate in the axilla group was 3.6%, which was not significantly different from that of the IMLN group (1.3%) (p=0.484). The five-year survival rates did not differ between the two groups (p=0.306). The overall recurrence rate and the locoregional recurrence rate also did not differ between the two groups (p=0.835 and p=0.582, respectively). The recurrence rate of IMLN (both ipsilateral and contralateral) metastasis was very low, accounting for 0.5% in the axilla group and 1.3% in the IMLN group (p=0.416).

Conclusion

The long-term follow-up results showed that there was no significant difference in both overall outcome and regional recurrence between the two groups. Therefore, the requirement for identification of nodal basins outside the axilla or IMLN sentinel biopsy should be reconsidered.

Ultrasound-guided sentinel node procedure for nonpalpable breast carcinoma

PURPOSE

Peritumoral and periareolar tracer injection techniques lead to different lymphatic drainage in sentinel lymph node biopsy procedures. In a prospective study, the visualization and identification rates of the ultrasound (US)-guided tracer injection technique for palpable and nonpalpable breast tumors were evaluated.

METHODS

In 1262 consecutive patients with cT₁₋₂N0 breast cancer, sentinel lymph node biopsy was performed following peritumoral tracer injection. In the case of nonpalpable breast lesions, Tc-99m nanocolloid injections were given using a 7.5 MHz US probe. In the case of ultrasonographically nonvisible microcalcifications, the US-guided injection technique was wire guided.

RESULTS

In 331 patients with nonpalpable breast lesions (26.2%), the lymphoscintigraphic visualization and surgical retrieval rates of axillary sentinel lymph nodes (SLNs) were 98.5 and 99.4%, respectively. For internal mammary (IM) SLNs, these rates were 21.1 and 17.8%, respectively. These rates were similar in patients with palpable and nonpalpable tumors. Axillary metastases were detected in 38.7% of the patients with palpable tumors versus 16.5% of those with nonpalpable tumors (P<0.001), whereas IM metastases were found in 4.8 and 3.0% of patients, respectively (P=0.165).

CONCLUSION

In nonpalpable breast lesions, the US-guided injection technique is an accurate technique for SLN identification and retrieval. The substantial rates of IM metastases in both palpable and nonpalpable lesions favor a peritumoral tracer injection technique.

Axillary staging in breast cancer patients with exclusive lymphoscintigraphic drainage to the internal mammary chain

BACKGROUND

The aim of this study was to evaluate the need of axillary staging in breast cancer patients showing exclusive lymphatic drainage to the internal mammary chain (IMC).

METHODS

A total of 2203 patients treated for breast carcinoma in three participating hospitals between July 2001 and July 2008 were analyzed. Only patients showing drainage to the IMC on preoperative lymphoscintigraphy were included. The number of harvested IMC sentinel lymph nodes (SLNs), axillary SLNs, and metastases were recorded. Finally, the follow-up of this group of patients was analyzed.

RESULTS

In 25/426 patients, drainage was exclusively to the IMC. Exploration of the axilla resulted in the harvesting of blue SLNs in 9 patients (36%) and the retrieval of an enlarged lymph node in 1 patient. In 4 of the remaining 15 patients, an axillary lymph node dissection (ALND) was done. Lymph node metastases were found in 3 patients who had blue axillary SLNs and in 1 patient who underwent ALND. In the 11 patients who had no blue SLNs and no ALND, no axillary recurrences were observed during follow-up (median = 26 months).

CONCLUSIONS

Proper staging of the axilla remains crucial in patients showing exclusive drainage to the IMC. When no axillary node can be retrieved, ALND remains subject to discussion.

Surgical approach to internal mammary sentinel node biopsy

BACKGROUND

Internal mammary node (IMN) metastasis has a similar prognostic importance as axillary nodal involvement. However, sampling of IMN is not performed routinely.

AIMS

To evaluate a simplified method for internal mammary sentinel node (IMSN) biopsy of breast cancer patients.

METHODS

A combination of simultaneous perilesional and intradermal radiocolloid injections over the lesion was used. All IMSNs were confirmed by lymphoscintigraphy and Carbon Nanoparticles Suspension Injection preoperatively and excised extrapleurally through the intercostal muscles.

RESULTS

Twenty-three of the 94 patients were found to have metastatic disease in the IMSNs. Four of 65 patients had metastases in the IMNs but not in the axilla. All 23 patients with positive IMSN were upstaged and received radiation to the internal mammary chain. The time from separating the pectoral major muscle to touch the node was ranged 21-48 min. The detecting sensitivity combined with preoperative lymphoscintigraphy, intraoperative gamma probe detection, and intraoperative black dye methods for IMSN was 100%.

CONCLUSIONS

The approach used is a reliable surgical technique for removing IMSN. It can improve the nodal staging in breast cancer with IMN metastases.

The sentinel node procedure in breast cancer: nuclear medicine as the starting point

Axillary node status is a major prognostic factor in early breast cancer. Staging with sentinel node biopsy (SNB) leads to a substantial reduction in surgical morbidity. Recent multiinstitutional studies revealed SNB false-negative rates ranging from 5.5% to 16.7%, higher than the target (<5%) set by the 2005 guidelines of the American Society of Clinical Oncology. These alarming data point to the necessity of optimization. Dual mapping with radiotracer and blue dye, combining 2 different injection sites, and routinely using lymphoscintigraphy may improve accuracy. Factors associated with decreased sensitivity, such as prior excisional biopsy or neoadjuvant chemotherapy, should be recognized. The use of SNB in situations with a high prevalence of node positivity (large tumor, multifocality) is controversial. The risk of missed disease after negative SNB ranges from 1% to 4% in patients with T1 tumor and up to 15% in patients with T3. With peritumoral injection, internal mammary drainage is seen in about 20% of cases. Patients combining internal mammary drainage with a positive axillary sentinel node have close to a 50% probability of internal mammary involvement. Lymphoscintigraphy might thus be helpful in selecting patients for whom internal mammary radiation has a high benefit-to-risk ratio.

Internal mammary lymph node recurrence: rare but characteristic metastasis site in breast cancer

Background

To assess the frequency of IMLN recurrence, its associated risk factors with disease-free interval (DFI) and its predicting factors on overall survival time.

Methods

133 cases of breast cancer IMLN recurrence were identified via the computerized CT reporting system between February 2003 and June 2008, during which chest CT for patients with breast cancer (n = 8867) were performed consecutively at Cancer Hospital, Fudan University, Shanghai, China. Patients' charts were retrieved and patients' characteristics, disease characteristics, and treatments after recurrence were collected for analysis. The frequency was 1.5% (133/8867).

Results

IMLN recurrence was presented as the first metastatic site in 121 (91%) patients while 88 (66.2%) had other concurrent metastases. Typical chest CT images included swelling of the IMLN at the ipsilateral side with local lump and sternal erosion located mostly between the second and third intercostal space. The median disease-free interval (DFI) of IMLN recurrence was 38 months. The independent factors that could delay the IMLN recurrence were small tumor size (HR 0.5 95%CI: 0.4 - 0.8; p = 0.002), and positive ER/PR disease (HR 0.6, 95% CI: 0.4 - 0.9; p = 0.006). The median survival time after IMLN recurrence was 42 months, with a 5-year survival rate of 30%. Univariate analysis showed four variables significantly influenced the survival time: DFI of IMLN recurrence (p = 0.001), no concurrent distant metastasis (p = 0.024), endocrine therapy for patients with positive ER/PR (p = 0.000), radiotherapy (p = 0.040). The independent factors that reduced the death risk were no concurrent distant metastases (HR: 0.7, 95% CI: 0.4 - 0.9; p = 0.031), endocrine therapy for patients with positive ER/PR status (HR: 0.2, 95% CI: 0.1 - 0.5; p = 0.001) and palliative radiotherapy (HR: 0.3, 95% CI: 0.1- 0.9; p = 0.026).

Conclusions

The risk of IMLN recurrence is low and there are certain characteristics features on CT images. ER/PR status is both a risk factor for DFI of IMLN recurrence and a prognostic factor for overall survival after IMLN recurrence. Patients with only IMLN recurrence and/or local lesion have a good prognosis.