The value of intraoperative frozen section examination of sentinel lymph nodes in breast cancer

Background

Sentinel node biopsy is a standard diagnostic component for the treatment of patients with a primary mammary carcinoma. By concomitantly performing intraoperative lymph node biopsy and primary tumor resection, patients with a positive sentinel node (SN) are not subjected to the inconvenience and risks of second surgical intervention. The aim of this retrospective study was to determine the sensitivity, accuracy and long-term consequences of the frozen section (FS) examination of the SN in breast cancer patients.

Methods

Sentinel lymph node biopsy was performed in 615 patients with an invasive tumor of the breast. Frozen sections of the SN were taken from the optimal cross-sectional surface. Serial sections were made from the remaining SN and stained using hematoxylin–eosin and immunohistochemistry.

Results

Sentinel node frozen biopsy accurately predicted the state of the axilla in 559 (90.7%) patients. There were 50 false-negative findings in patients with sentinel node metastases. The sensitivity and specificity of the intraoperative frozen section examination were 71.6% and 100%, respectively. Follow-up (mean 36.3 months) of all false-negative cases showed no development of local axillary recurrence. The results demonstrated no significant relation between tumor size and frozen section sensitivity. Frozen section investigation was less sensitive in ascertaining micrometastases (sensitivity 61.1%) than macrometastases (sensitivity 84.0%, p < 0.001).

Conclusion

Intraoperative frozen section examination of the sentinel node is a useful predictor of axillary lymph node status in breast cancer patients. Seventy-two percent of the patients with metastatic disease were correctly diagnosed and spared a second surgical procedure.     

The role of sentinel node biopsy in ductal carcinoma in situ of the breast

Aim

Sentinel node biopsy (SNB) is an accepted alternative to lymphadenectomy in the case of invasive breast carcinoma, although the sentinel node's role in ductal carcinoma in situ (DCIS) diagnosed on core needle biopsy has not been well defined nevertheless guidelines recommend this procedure. The purpose of this study was to determine the diagnostic value of sentinel nodes in female patients with primary DCIS using core needle stereotactic biopsy.

Material and methods

Between the years 2000 and 2005, 261 patients were diagnosed with DCIS by core needle biopsy. In this group, 183 patients underwent SNB to determine lymph node involvement. Those patients with metastases to the sentinel node underwent axillary lymphadenectomy.

Results

In the group of 183 patients that underwent SNB, 10 patients (5.5%) showed metastases to the sentinel lymph node. Histopathological studies of the primary lesions of these 10 patients revealed invasive ductal carcinoma in 6 cases (3.5%) and 1 case (0.5%) of invasive lobular carcinoma. Only 3 of the patients (1.5%) were given a final diagnosis of DCIS with metastases to sentinel lymph nodes, of which 2 cases were DCIS and 1 case was DCIS with microinvasion. Axillary lymphadenectomy performed on patients with abnormal SNB showed involvement of other axillary lymph nodes in 4 patients.

Conclusions

SNB as a diagnostic tool in DCIS remains controversial as the number of cases of axillary lymph node metastases is minuscule. The biggest clinical challenge in this situation is a group of patients with primary diagnosis of DCIS in which invasive components are seen by mammotomic biopsy.     

Outcome following sentinel lymph node biopsy-guided decisions in breast cancer patients with conversion from positive to negative axillary lymph nodes after neoadjuvant chemotherapy

Purpose

Many breast cancer patients with positive axillary lymph nodes achieve complete node remission after neoadjuvant chemotherapy. The usefulness of sentinel lymph node biopsy in this situation is uncertain. This study evaluated the outcomes of sentinel biopsy-guided decisions in patients who had conversion of axillary nodes from clinically positive to negative following neoadjuvant chemotherapy.

Methods

We reviewed the records of 1247 patients from five hospitals in Korea who had breast cancer with clinically axillary lymph node-positive status and negative conversion after neoadjuvant chemotherapy, between 2005 and 2012. Patients who underwent axillary operations with sentinel biopsy-guided decisions (Group A) were compared with patients who underwent complete axillary lymph node dissection without sentinel lymph node biopsy (Group B). Axillary node recurrence and distant recurrence-free survival were compared.

Results

There were 428 cases in Group A and 819 in Group B. Kaplan–Meier analysis showed that recurrence-free survivals were not significantly different between Groups A and B (4-year axillary recurrence-free survival: 97.8 vs. 99.0%; p = 0.148). Multivariate analysis also indicated the two groups had no significant difference in axillary and distant recurrence-free survival.

Conclusions

For breast cancer patients who had clinical conversion of axillary lymph nodes from positive to negative following neoadjuvant chemotherapy, sentinel biopsy-guided axillary surgery, and axillary lymph node dissection without sentinel lymph node biopsy had similar rates of recurrence. Thus, sentinel biopsy-guided axillary operation in breast cancer patients who have clinically axillary lymph node positive to negative conversion following neoadjuvant chemotherapy is a useful strategy.

     

The roles of <Superscript>18</Superscript>F-FDG-PET/CT and US-guided FNAC in assessment of axillary nodal metastases in breast cancer patients

Background

There is a need for less invasive techniques for preoperative identification of axillary lymph node (ALN) metastases.

Method

Patients underwent ultrasonography (US) and ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT), and then US-guided fine needle aspiration cytology (FNAC) and/or sentinel lymph node (SLN) biopsy were performed based on the US findings of the ALNs. Subsequently, patients with positive FNAC as well as those with positive SLN underwent axillary lymph node dissection (ALND). Postoperatively, removed SLNs and ALNs were examined histologically.

Results

Fifty (85 %) of 59 patients with positive ¹⁸F-FDG uptake in the axilla had axillary metastases, but ¹⁸F-FDG uptake results were false-positive in 9 (15 %) cases. On the other hand, 29 patients with positive FNAC underwent ALND without the need for SLN biopsy, while the remaining 20 patients with negative FNAC as well as 249 patients with negative US findings underwent SLN biopsy. Subsequently, 68 patients with positive SLN underwent ALND.

Conclusions

Positive FDG uptake in the axilla does not always indicate axillary metastasis. US-guided FNAC is useful to avoid unnecessary ALND in patients with positive ¹⁸F-FDG uptake. However, SLN biopsy is needed in patients with negative US findings of the ALNs and those with negative FNAC.

     

The significance of immunohistochemistry positivity in sentinel nodes which are negative on haematoxylin and eosin in breast cancer

Introduction

Sentinel lymph node (SLN) biopsy allows a more detailed examination of a smaller number of lymph nodes in patients with clinically node negative breast cancer. Immunohistochemistry detects small tumour burden not routinely seen on haematoxylin and eosin (H&E). The significance of such findings remains to be fully elucidated.

Aim

To assess the axillary disease burden of patients in whom the sentinel lymph node biopsy was positive on immunohistochemistry and negative on H and E.

Methods

An analysis of patients who underwent SLN mapping for breast cancer at St Vincent's University Hospital from January 1st, 2000 to December 31st, 2006 was conducted. All SLNs were assessed by serial H&E and IHC sections. Patients with micrometastases (0.2–2 mm) underwent a completion axillary lymph node dissections (CLND). Patients with ITC (<0.2 mm) were individually discussed and a CLND was performed selectively based on additional clinicopathological criteria and patient preference. Analysis of the additional nodes from CLND was performed. Patients were followed for a median of 27 months (range 12–72 months).

Results

1076 patients who underwent SLN were included for analysis. 211 (20%) had a positive SLN biopsy using H&E. Forty-nine patients (5%) had a negative SLN on H&E which was positive on IHC. Of these, 15 had micrometastases and underwent a CLND. Two had further axillary nodal disease. ITC were found in the remaining 34 patients. Sixteen of these patients underwent a CLND. Five of this group had further nodal disease.

Conclusion

Micrometastases and isolated tumour cells, detected only by immunohistochemical analysis of sentinel lymph nodes, are associated with further positive nodes in the axilla in up to 15% of patients. This upstaging of disease may impact upon patient outcome.     

Selection for axillary clearance in breast cancer (ultrasound negative,sentinel node positive patients have low rates of further metastases)

Background

The aim of this study was to determine whether we could identify a subset of axillary clearance patients in whom the procedure yielded negative nodes and was therefore of no therapeutic benefit.

Methods

Over a three year period 138 patients underwent axillary clearance at our unit. The axillae of all patients were assessed preoperatively with clinical examination, ultrasound (USS) and FNAC if suspicious nodes identified. Patients with clinically malignant nodes or positive FNAC underwent axillary node clearance where appropriate, whilst completion axillary node clearance was performed in those who had no preoperative evidence of metastatic axillary disease but positive sentinel node biopsy (SNB)/axillary node sample (ANS).

Results

Of the 138 patients, the indications for axillary clearance were positive FNAC or clinically malignant nodes in 89 and positive SNB/ANS in the remaining 49. Patients with preoperative evidence of axillary metastases had significantly more positive nodes compared to those who underwent SNB and completion ANC 4.6 vs. 3.1 p = 0.037. Of the patients with ultrasonographically normal axillae but positive SNB, 8.7% had further nodal metastases at completion ANC. This was significantly less than in those with abnormal USS (negative FNAC) and positive SNB (41.7%); p = 0.033.

Conclusions

Preoperative ultrasound in conjunction with FNAC and clinical judgement identifies most patients with positive axillary nodes and such patients have more widespread disease. The additional value of completion axillary ANC in patients with ultrasonographically normal axillae but positive SNB appears small as sentinel node ‘biopsy’ serves to clear the axilla of metastases in most of these patients.     

Preoperative predictors of high and low axillary nodal burden in Z0011 eligible breast cancer patients with a positive lymph node needle biopsy result

Background

Z0011 trial showed that early breast cancer patients with low axillary nodal burden, may be spared an axillary lymph node dissection with no survival compromise. Axillary lymph node dissection can be reserved for patients with a high axillary nodal burden. We aim to determine the preoperative factors that could distinguish between low and high axillary nodal burden in Z0011 eligible patients with a needle biopsy proven metastatic node.

Accuracy of sentinel lymph node biopsy after neo-adjuvant chemotherapy in patients with locally advanced breast cancer and clinically positive axillary nodes

Background

Feasibility and accuracy of sentinel node biopsy (SLNB) after the delivery of neo-adjuvant chemotherapy (NAC) is controversial. We here report our experience in NAC-treated patients with locally advanced breast cancer and clinically positive axillary nodes, and compare it with the results from our previous randomized trial assessing SLNB in early-stage breast cancer patients.

Patients and methods

Sixty-four consecutive patients with large infiltrating tumor and clinically positive axillary nodes received NAC and subsequent lymphatic mapping, SLNB and complete axillary lymph node dissection (ALND). The status of the sentinel lymph node (SLN) was compared to that of the axilla.

Results

At least one SLN was identified in 60 of the 64 patients (93.8%). Among those 60 patients, 37 (61.7%) had one or more positive SLN(s) and 23 (38.3%) did not. Two of the patients with negative SLN(s) presented metastases in other non-sentinel nodes. SLNB thus had a false-negative rate, a negative predictive value and an overall accuracy of 5.1%, 91.3% and 96.7%, respectively. All these values were similar to those we reported for SLNB in the settings of early-stage breast cancer.

Conclusion

SLNB after NAC is safe and feasible in patients with locally advanced breast cancer and clinically positive nodes, and accurately predicts the status of the axilla.     

Analysis of direct oil contrast lymphography of upper limb lymphatics traversing the axilla – A lesson from the past – Contribution to the concept of axillary reverse mapping

Introduction

Axillary reverse mapping (ARM) is a method to preserve upper extremity (UE) lymphatics during axillary surgery in breast cancer patients. This may reduce the incidence of lymphedema. Very precise method to demonstrate lymphatic drainage is direct X-ray lymphography.

Materials and methods

The evaluation of direct lymphography X-ray images of the axilla and proximal part of the upper extremity was performed in 9 subjects. As contrast was used Lipiodoil injected on the dorsal side of hand.

Results

The lymph from UE is drained by 2–4 main afferent collectors, which in 5 of 9 cases entered into one node in the lateral axilla (ARM node). This node was considered to be the sentinel lymph node for the UE. In 4 cases a cranial collector was shown, which led directly to nodes in the upper part of the axilla. This collector had numerous anastomoses with other collectors before entering the axillary nodes. The most important finding is the demonstration of numerous lymphatic anastomoses that take place between all imaged nodes in the axilla including the caudal nodes, which is the most frequent localization of the breast sentinel lymph node.

Conclusion

The relationship of lymphatic drainage of the UE and breast are closely related and share numerous connections. These connections represent the main problem of the ARM concept because they may pose potencional route for metastatic cancer cells in sentinel node positive breast cancer patients. Further studies are necessary to improve understanding of this method.Axillary reverse mapping – breast cancer – lymphedema – sentinel node biopsy.     

Sentinel lymph node biopsy and axillary dissection in breast cancer: results in a large series

BACKGROUND: Axillary lymph node dissection is an established component of the surgical treatment of breast cancer, and is an important procedure in cancer staging; however, it is associated with unpleasant side effects. We have investigated a radioactive tracer-guided procedure that facilitates identification, removal, and pathologic examination of the sentinel lymph node (i.e., the lymph node first receiving lymphatic fluid from the area of the breast containing the tumor) to predict the status of the axilla and to assess the safety of foregoing axillary dissection if the sentinel lymph node shows no involvement. METHODS: We injected 5-10 MBq of 99mTc-labeled colloidal particles of human albumin peritumorally in 376 consecutive patients with breast cancer who were enrolled at the European Institute of Oncology during the period from March 1996 through March 1998. The sentinel lymph node in each case was visualized by lymphoscintigraphy, and its general location was marked on the overlying skin. During breast surgery, the sentinel lymph node was identified for removal by monitoring the acoustic signal from a hand-held gamma ray-detecting probe. Total axillary dissection was then carried out. The pathologic status of the sentinel lymph node was compared with that of the whole axilla. RESULTS: The sentinel lymph node was identified in 371 (98.7%) of the 376 patients and accurately predicted the state of the axilla in 359 (95.5%) of the patients, with 12 false-negative findings (6.7%; 95% confidence interval = 3.5%-11.4%) among a total of 180 patients with positive axillary lymph nodes. CONCLUSIONS: Sentinel lymph node biopsy using a gamma ray-detecting probe allows staging of the axilla with high accuracy in patients with primary breast cancer. A randomized trial is necessary to determine whether axillary dissection may be avoided in those patients with an uninvolved sentinel lymph node.     

Lymphatic mapping with intralesional tracer administration in breast carcinoma patients

BACKGROUND: The objectives of the study were to determine how often a sentinel lymph node is visualized by lymphoscintigraphy in breast carcinoma patients, how often the sentinel lymph node is identified during surgery, and the sensitivity of these procedures to identify the presence of axillary lymph node metastasis. METHODS: A total of 136 patients were enrolled in 2 hospitals. Preoperative dynamic and static lymphoscintigraphy were performed; in addition, both a vital dye and a gamma detection probe were used intraoperatively. The tracers were injected into the primary lesion. Sentinel lymph node biopsy was followed by completion axillary lymph node dissection. The sentinel lymph nodes and other axillary lymph nodes were examined routinely and by immunohistochemical staining. RESULTS: A sentinel lymph node was visualized by lymphoscintigraphy in 118 patients (87%). During the operation a sentinel lymph node was localized in 126 patients (93%). A total of 224 sentinel lymph nodes were harvested (average of 1.7 and range of 1-4 sentinel lymph nodes per patient). Of all the sentinel lymph nodes, 37 were blue (17%), 68 were radioactive (30%), and 119 were both blue and radioactive (53%). The sentinel lymph nodes contained metastatic disease in 56 patients (44%). Three sentinel lymph node biopsies were false-negative (sensitivity 95%). CONCLUSIONS: Sentinel lymph node biopsy with preoperative lymphoscintigraphy after intralesional tracer administration and intraoperative use of both a gamma detection probe and a vital dye is a reliable technique for staging the axilla of breast carcinoma patients.     

A prospective validation study of sentinel lymph node biopsy in multicentric breast cancer: SMMaC trial

Background

Multicentric breast cancer is often considered a contra-indication for sentinel lymph node (SLN) biopsy due to concerns with sensitivity and false negative rate. To assess SLN feasibility and accuracy in multicentric breast cancer, the multi-institutional SMMaC trial was conducted.

Methods

In this study 30 patients with multicentric breast cancer and a clinically negative axilla were prospectively included. Periareolar injection of radioisotope and blue dye was administered. In all patients SLN biopsy was validated by back-up completion axillary lymph node dissection.

Results

the SLN was successfully identified in 30 of 30 patients (identification rate 100%). The incidence of axillary metastases was 66.7% (20/30). The false negative rate was 0% (0/20) and the sensitivity was 100% (20/20). The negative predictive value was 100% (10/10).

Conclusion

SLN biopsy in multicentric breast cancer seems feasible and accurate and should therefore be considered in patients with multicentric breast cancer and clinically negative axilla.     

Staging and management of axillary lymph nodes in patients with local recurrence in the breast or chest wall after a previous negative sentinel node procedure

Objective

To evaluate axillary staging and management in patients with local recurrence (LR) after a previous negative sentinel lymph node biopsy (SNB).

Methods

Between 1999 and 2008, 130 patients with previous negative SNB developed a LR of breast or chest wall. After examination of clinical records, 70 patients met the inclusion criteria and remained available for analysis.

Results

Thirty-seven patients were treated with axillary lymph node dissection (ALND), followed by axillary radiotherapy in 9 cases. In 26 of these 37 patients no positive axillary lymph nodes were found. Nineteen patients received no treatment of the axilla at all. Of those, 9 were older than 70 years of age at diagnosis of LR. In 13 patients a second SNB was attempted, but was successful in only 5 cases. Eight patients underwent a complementary ALND. Overall, positive lymph nodes were detected in 13 of the 50 patients who underwent axillary staging, either by SNB or ALND. The median length of follow-up of the 70 patients following their diagnosis of LR was 24 months (range 2–81 months). During this follow-up period one patient developed an axillary recurrence. This was a patient who refused to undergo ALND but was given locoregional radiotherapy instead.

Conclusions

In the absence of guidelines for staging and management of the axilla at time of LR of breast or chest wall, many different strategies are being used. Considering the high rate of positive axillary lymph nodes in these patients, repeat surgical staging is appropriate.     

Sentinel lymph node biopsy in patients with breast cancer using superparamagnetic iron oxide and a magnetometer

Background

Some hospitals lack facilities for radioisotopes in sentinel node biopsy. A novel method is used with a superparamagnetic tracer and a magnetometer instead of a radioisotope.

Methods

Thirty patients were included in the study after obtaining IRB approval. Superparamagnetic iron oxide and patent blue dye were injected in the subareolar breast tissue. Following a few minutes of massage to promote migration of the iron tracer and blue dye throughout the lymphatic vessels, the axillary lymph nodes were detected transdermally using a handheld magnetometer and followed by standard axillary dissection in all patients.

Results

Of 30 patients evaluated, sentinel lymph nodes were identified in 90% (27/30) using both blue dye and magnetic tracer. Sentinel lymph nodes were identified using the magnetic method in 23/30 (77%) and blue dye in 24/30 (80%). There was one false-negative sentinel node, resulting in an overall sensitivity of 6/7 (86%).

Conclusions

This is the first study to use a magnetic tracer to identify sentinel lymph nodes in patients with breast cancer. This new technique may alter the role of radioisotopes with further refinement and experience.     

Sentinel lymph node biopsy in the management of breast cancer

Sentinel node localization is the second most important development in this century after conservative lumpectomy for the treatment of early breast cancer. The sentinel node mapping is a new multidisciplinary approach for staging of axilla in an accurate and less morbid way as compared to axillary node dissection. Sentinel lymph node biopsy in patients with breast cancer has been adopted rapidly into clinical practice. The accuracy of sentinel lymph node biopsy is more than 95%, when performed meticulously (by an experienced multidisciplinary team) with proper patient selection. Sentinel lymph node biopsy is most widely used for both palpable and non-palpable T1 and T2 tumors. Recent studies show application of sentinel lymph node technique in patients with locally advanced breast cancer and after neoadjuvant chemotherapy. Therefore, sentinel lymph node biopsy technique has application in developing countries and other countries where screening for breast cancer is not common and most patients present relatively in advanced stage of the disease. Several aspects of the sentinel lymph node biopsy including technique, case selection, pathologic analysis and accuracy with supportive important studies published in the literature will be discussed in this review.     

Sentinel Node Biopsy in Early Breast Cancer Patients with Palpable Axillary Node

Background: Sentinel lymph node biopsy is a reliable method for evaluation of the axillary lymph node status in early stage breast cancer patients with non-palpable lymph nodes. The present study evaluated the status of sentinel and non-sentinel lymph nodes in T1T2 patients with palpable axillary lymph nodes. Materials and Methods: One hundred and two women with early breast cancer were investigated in this study. Patients were selected for axillary sentinel lymph node biopsy and then surgery .Then the rates of false negative and true positive, and diagnostic accuracy of sentinel lymph nodes biopsy were evaluated. In addition, the hormone receptors status of the tumor was determined through IHC and data was analyzed in SPSS21. Results: In this study, the mean age of the patients was 49 years, 85% had invasive ductal carcinoma  in their pathology reports, 77% were ER/PR positive, 30% HER2 positive and 9.8% triple negative and 69% had KI67<14%. In frozen pathology, 15.7 and 84.3% were sentinel positive and negative, respectively, and in the final pathology, 41 and 58.8% were sentinel positive and negative, respectively. This difference arises from the false negative rate of the frozen pathology, which was about 31.3%. The sensitivity, specificity, and diagnostic accuracy of the frozen section were 24, 90 and 43%, respectively. Lymphovascular invasion is an important effective factor in the involvement of sentinel and non-sentinel lymph nodes. Statistical analysis showed that the probability of sentinel and non-sentinel lymph nodes involvement was higher in receptor positive patients and those with KI67>14% (p<0.002) whereas the rate of involvement was lower in triple negative patients. Conclusion: Sentinel node biopsy can be used in a significant percentage of breast cancer patients with palpable and reactive axillary lymph nodes.     

The role of preoperative axillary ultrasound and fine-needle aspiration cytology in identifying patients with extensive axillary lymph node involvement

Introduction

In the recent past, both clinically node-positive and node-negative but sentinel node-positive patients underwent axillary lymph node dissection (ALND), although the two groups seem to have substantially different degree of nodal involvement.

Sentinel lymph node biopsy after previous axillary surgery: A review

Background

The utility of axillary lymph node dissection (ALND) in the management of breast cancer is currently under close scrutiny. At primary diagnosis the use of sentinel lymph node biopsy (SLNB) has restricted ALND for proven nodal disease, however the management of the axilla at local (in-breast) relapse is less clearly defined with many undergoing routine ALND. This review examines the role of SLNB in the re-operative setting with the objective of developing an axillary management algorithm for use at in-breast local relapse, and restricting ALND to node-positive recurrent cancers.

Methods

We reviewed published reports of SLNB at local relapse in women who had previously undergone axillary surgery either as lymph node biopsy, SLNB, axillary sampling (AS) or axillary lymph node dissection (ALND).

Results

There have been no randomised trials. Six reports with 327 cases were identified; of which 61% (199/327) had previous SLNB or ALND with <9 nodes removed. There was an overall successful sentinel lymph node (SLN) localisation at re-operation of 69% (227/327), range of 51-100%. In patients who have previously had limited axillary surgery (<9 nodes removed), the rate of successful SLN localisation was 83% (165/199), range of 68-100% and 142/165 (86%, range 80-100%) were node negative. In these highly selected patients no axillary recurrences were noted in those who had a negative SLN at re-operation after 26-46 months follow up.

Conclusion

SLNB at in-breast relapse is feasible and safe with successful localisation related to the extent of previous axillary surgery.     

A mathematical prediction model incorporating molecular subtype for risk of non-sentinel lymph node metastasis in sentinel lymph node-positive breast cancer patients: a retrospective analysis and nomogram development

Background

Molecular subtype of breast cancer is associated with sentinel lymph node status. We sought to establish a mathematical prediction model that included breast cancer molecular subtype for risk of positive non-sentinel lymph nodes in breast cancer patients with sentinel lymph node metastasis and further validate the model in a separate validation cohort.

Methods

We reviewed the clinicopathologic data of breast cancer patients with sentinel lymph node metastasis who underwent axillary lymph node dissection between June 16, 2014 and November 16, 2017 at our hospital. Sentinel lymph node biopsy was performed and patients with pathologically proven sentinel lymph node metastasis underwent axillary lymph node dissection. Independent risks for non-sentinel lymph node metastasis were assessed in a training cohort by multivariate analysis and incorporated into a mathematical prediction model. The model was further validated in a separate validation cohort, and a nomogram was developed and evaluated for diagnostic performance in predicting the risk of non-sentinel lymph node metastasis. Moreover, we assessed the performance of five different models in predicting non-sentinel lymph node metastasis in training cohort.

Results

Totally, 495 cases were eligible for the study, including 291 patients in the training cohort and 204 in the validation cohort. Non-sentinel lymph node metastasis was observed in 33.3% (97/291) patients in the training cohort. The AUC of MSKCC, Tenon, MDA, Ljubljana, and Louisville models in training cohort were 0.7613, 0.7142, 0.7076, 0.7483, and 0.671, respectively. Multivariate regression analysis indicated that tumor size (OR?=?1.439; 95% CI 1.025–2.021; P?=?0.036), sentinel lymph node macro-metastasis versus micro-metastasis (OR?=?5.063; 95% CI 1.111–23.074; P?=?0.036), the number of positive sentinel lymph nodes (OR?=?2.583, 95% CI 1.714–3.892; P?<?0.001), and the number of negative sentinel lymph nodes (OR?=?0.686, 95% CI 0.575–0.817; P?<?0.001) were independent statistically significant predictors of non-sentinel lymph node metastasis. Furthermore, luminal B (OR?=?3.311, 95% CI 1.593–6.884; P?=?0.001) and HER2 overexpression (OR?=?4.308, 95% CI 1.097–16.912; P?=?0.036) were independent and statistically significant predictor of non-sentinel lymph node metastasis versus luminal A. A regression model based on the results of multivariate analysis was established to predict the risk of non-sentinel lymph node metastasis, which had an AUC of 0.8188. The model was validated in the validation cohort and showed excellent diagnostic performance.

Conclusions

The mathematical prediction model that incorporates five variables including breast cancer molecular subtype demonstrates excellent diagnostic performance in assessing the risk of non-sentinel lymph node metastasis in sentinel lymph node-positive patients. The prediction model could be of help surgeons in evaluating the risk of non-sentinel lymph node involvement for breast cancer patients; however, the model requires further validation in prospective studies.

     

Initial experience with sentinel node biopsy in breast cancer at the National Cancer Center Hospital East

BACKGROUND: Axillary lymph node dissection is an important procedure in the surgical treatment of breast cancer. Axillary lymph node dissection is still performed in over half of breast cancer patients having histologically negative nodes, regardless of the morbidity in terms of axillary pain, numbness and lymphedema. The first regional lymph nodes draining a primary tumor are the sentinel lymph nodes. Sentinel node biopsy is a promising surgical technique for predicting histological findings in the remaining axillary lymph nodes, especially in patients with clinically node-negative breast cancer, and a worldwide feasibility study is currently in progress. METHODS: Intraoperative lymphatic mapping and sentinel node biopsy were performed in the axilla by subcutaneous injection of blue dye (indigocarmine) in 88 cases of stage 0-IIIB breast cancer. Sentinel lymph nodes were identified by detecting blue-staining lymph nodes or dye-filled lymphatic tracts after total or partial mastectomy. Finally, axillary lymph node dissection was performed up to Levels I and II or more. RESULTS: Sentinel lymph nodes were successfully identified in 65 of the 88 cases (74%). In the final histological examination, the sentinel lymph nodes in 40 cases were negative, including four cases with non-sentinel-node-positive breast cancer (specificity, 100%; sensitivity, 86%). In nine (31%) of the 29 cases with histologically node-positive breast cancer, the sentinel lymph nodes were the only lymph nodes affected. Axillary lymph node status was accurately predicted in 61 (94%) of the 65 cases. CONCLUSIONS: Although it was the initial experience at the National Cancer Center Hospital East, sentinel node biopsy proved feasible and successful. This method may be a reasonable alternative to the standard axillary lymph node dissection in patients with early breast cancer.