Predictive factors for metastatic involvement of nonsentinel nodes in patients with breast cancer

Predictive Factors for the Status of Non-sentinel Nodes in Breast Cancer Patients with Tumor Positive Sentinel Nodes

In patients with tumor positive sentinel nodes, axillary lymph node dissection is routinely performed while a majority of these patients have no tumor involvement in the non-sentinel nodes. The authors tried to identify a subgroup of patients with a tumor positive sentinel node without non-sentinel node tumor involvement. In 135 consecutive patients with tumor positive sentinel nodes and axillary lymph node dissection performed, the incidence of non-sentinel node involvement according to tumor and sentinel node related factors was examined. The size of the sentinel node metastasis, size of primary tumor and number of tumor positive sentinel nodes were the three factors significantly predicting the status of the non-sentinel nodes. The size of the sentinel node metastasis was the strongest predictive factor (P < 0.0001). In a subgroup of 41 patients with a stage T1 tumor and micrometastatic involvement in the sentinel node only 2 patients (5%) had non-sentinel node involvement. In patients with small primary tumors and micrometastatic involvement of the sentinel nodes, the chance of non-sentinel node involvement is small but cannot be discarded. Because the clinical relevance of micrometastases in lymph nodes is still unclear it is not advisable to omit axillary lymph node dissection even in these patients.

Prediction of tumour involvement in remaining axillary lymph nodes when the sentinel node in a woman with breast cancer contains metastases

Background

In a significant proportion of women with breast cancer, the sentinel node is the only involved node in the axilla. The purpose of this study was to identify factors associated with histologically positive non-sentinel lymph nodes.

Methods

Between 1997 and 2002, 800 women with early breast cancer underwent sentinel node biopsy. In 263 patients the node contained metastases, including 83 with micrometastases detected by immunohistochemistry (IHC), 40 micrometastases detected on haematoxylin, eosin and safranine (HES) staining, and 140 macrometastases. All clinical and histological criteria were recorded and analysed with reference to histology of the non-sentinel node.

Results

The risk of metastasis in the non-sentinel lymph node was related to the volume of the tumour in the sentinel node. Non-sentinel nodes were involved in five (6·0 per cent) of 83 women when the sentinel node contained only micrometastatic cells detected on IHC, and in three (7·5 per cent) of 40 women when micrometastases were detected by HES, compared with 55 (39·3 per cent) of 140 when the sentinel node contained macrometastases on HES staining. Univariate analysis revealed a significant association between non-sentinel node involvement and type of metastasis within the sentinel node, clinical primary tumour size, palpable axillary lymph nodes before operation, pathological primary tumour size and the presence of peritumoral lymphovascular invasion. On multivariate analysis, the type of metastasis within the sentinel node (P &lt; 0·001), histological tumour size greater than 20 mm (P = 0·017) and the presence of palpable axillary nodes before operation (P = 0·014) remained significant.

Conclusion

Clinical and pathological factors associated with sentinel node histology can reliably predict women for whom further axillary clearance is recommended, but it is not yet possible to determine a subgroup of patients in whom the sentinel node is the only involved node and for whom further axillary treatment may be unnecessary.

A prospective study of the value of axillary node sampling in addition to sentinel lymph node biopsy in patients with breast cancer

AIMS

Limitations of sentinel lymph node biopsy (SLNB) include the occurrence of false negative (FN) results and the need to further treat SLNB positive axillae. The aims of this study were to: (1) compare the accuracy of SLNB alone to a combined SLNB and axillary sampling procedure (SLNB+AS). (2) evaluate if the additional AS could identify those SLNB positive cases with no further disease in the axilla.

METHODS

Sixty-seven combined SLNB+AS procedures were performed prospectively in 66 patients, followed by Level II axillary dissection. Additionally sampled nodes were recorded if they were clinically suspicious or not at intra-operative palpation.

RESULTS

The FN rate for SLNB alone was 14.3%, whilst that for SLNB+AS was reduced to 3.6%. However, the benefit of additional sampling was only seen in those cases with tumours >/=3 cm and clinically suspicious nodes (n=12). Of 12 cases with a positive SLN but negative AS, 4 (30%) were found to have disease elsewhere in the axilla.

CONCLUSION

SLNB is inaccurate in the presence of suspicious nodes found at operation and careful palpation and sampling of these nodes is recommended, especially with larger tumours. In SLNB positive patients, AS is unreliable in predicting those patients with no further disease in the axilla.

Pathological work-up of sentinel lymph nodes in breast cancer. Review of current data to be considered for the formulation of guidelines

Controversies and inconsistencies regarding the pathological work-up of sentinel lymph nodes (SNs) led the European Working Group for Breast Screening Pathology (EWGBSP) to review published data and current evidence that can promote the formulation of European guidelines for the pathological work-up of SNs. After an evaluation of the accuracy of SN biopsy as a staging procedure, the yields of different sectioning methods and the immunohistochemical detection of metastatic cells are reviewed. Currently published data do not allow the significance of micrometastases or isolated tumour cells to be established, but it is suggested that approximately 18% of the cases may be associated with further nodal (non-SN) metastases, i.e. approximately 2% of all patients initially staged by SN biopsy. The methods for the intraoperative and molecular assessment of SNs are also surveyed.

Current status of sentinel lymph node mapping and biopsy: facts and controversies

Lymphatic mapping and sentinel lymph node biopsy were first reported in 1977 by Cabanas for penile cancer. Since that time, the technique has become rapidly assimilated into clinical practice. Morton first described the application of lymphatic mapping for melanoma only a decade ago, and this technique is now accepted as the standard of care. The application for lymphatic mapping and sentinel lymph node biopsy in breast cancer remains approximately 5 years behind its utilization in melanoma. This technique has the potential to be utilized in all solid tumors. The rapid assent of this technique in clinical practice is the result of multiple factors, including accuracy, decreased morbidity, and supplying the pathologist with only a few nodes to allow a more focused and sensitive pathologic evaluation. Despite the success and acceptance of lymphatic mapping, many controversies remain. We have attempted to clearly highlight these controversies in this review.

Effect of Increasing the Surface Sampled by Imprint Cytology on the Intraoperative Assessment of Axillary Sentinel Lymph Nodes in Breast Cancer Patients

As axillary sentinel nodes predict the nodal status and may allow dissection of the axilla on a selective basis we assessed the effects of increasing the surface sampled during intraoperative imprint cytology. Sentinel nodes from 110 patients identified with Patent blue and/or the high radioactivity due to the uptake of 99m-Tc-labeled colloidal albumin were analyzed via hematoxylin and eosin-stained touch preparations. Imprint cytology was performed either on bisected nodes (Protocol One; n = 55) or on sentinel nodes sliced into multiple pieces at 2- to 3-mm intervals (Protocol Two; n = 55). The sentinel nodes were submitted in toto to permanent step sectioning and immunostaining for cytokeratins. There were equal numbers of patients with involved nodes in the two groups assessed. With Protocols One and Two the imprints had sensitivities of 52 and 61 per cent, negative predictive values of 74 and 78 per cent, and false negative rates of 47 and 39 per cent, respectively. No macrometastasis missed by Protocol Two was absent from the surface sampled. These data suggest that increasing the surface sampled improves the proportion of involved sentinel nodes detected intraoperatively by imprint cytology, but a number of metastatic nodes still remain undetected by this method. The sampling of multiple surfaces is encouraged for a more accurate intraoperative assessment.

Sentinel lymphadenectomy without systematic axillary dissection in breast cancer patients: predictors of non-sentinel lymph node metastasis

AIMS

To identify factors predicting metastatic involvement of non sentinel axillary lymph nodes in breast cancer patients who underwent sentinel lymph node (SLN) biopsy followed by complete axillary dissection only in case of metastatic sentinel lymph node.

METHODS

A prospective database including 165 breast cancer patients who underwent SLN biopsy without further complete axillary dissection in case of non-metastatic SLN was reviewed. Primary tumor size, pathologic grade, lymphatic invasion in the primary tumor, estrogen receptor status, tumor size in the SLN and number of metastatic SLNs were tested as possible predictors of metastatic involvement of non-SLN.

RESULTS

The sentinel lymph node detection rate was 97% (160/165 patients). The mean number of SLNs per patient was 1.8 (range: 1-5). Fifty patients (31.3%) had a metastatic axillary SLN: 10 of the 42 patients with T1a or T1b breast tumors and 40 of the 118 patients with T1c< or = 15mm tumors. Fifteen of the 50 patients with metastatic SLN had metastatic non-SLN. Primary tumor size, tumor size in the SLN, pathologic grade, estrogen receptor status and age were not significantly associated with metastatic involvement of non-SLN. Number of metastatic SLNs fell short of reaching statistical significance (P: NS). Lymphatic invasion in the primary tumor was the only factor significantly associated with the presence of tumor in the non SLN (P<0.01).

CONCLUSION

In our series, only lymphatic invasion in the primary tumor was correlated with metastases detection in the non-SLN. We could not identify a subset of patients without metastatic non-SLN in patients with metastatic SLN.

Extracapsular extension of the sentinel lymph node metastasis: a predictor of nonsentinel node tumor burden

OBJECTIVE

To identify predictors of nonsentinel node (NSN) tumor involvement in patients with a tumor-involved sentinel node (SN).

SUMMARY BACKGROUND DATA

For many breast cancer patients who undergo intraoperative lymphatic mapping and sentinel lymphadenectomy (LM/SL), the SN is the only tumor-involved axillary node. Associations between NSN tumor involvement and several clinical and histopathologic factors have been identified. The authors hypothesize that extracapsular extension (ECE) of the SN metastasis is highly predictive of NSN tumor involvement.

METHODS

Between May 1998 and December 2001, 260 patients (263 cases) with clinical T1 or T2 (<5.0 cm) breast cancer underwent LM/SL at the University of North Carolina, using a combined blue dye and technetium sulfur colloid technique. In all cases with a tumor-involved SN, axillary lymph node dissection (ALND) was recommended. Statistical analysis, with Pearson chi-square tests, Fisher exact test, and multiple logistic regression, was performed.

RESULTS

The SN contained tumor in 74 (28.1%) cases. ALND was performed in 70 of the 74 cases. ECE of the SN metastasis was present in 18 (25.7%) of the 70 cases. Patients with ECE of the SN metastasis were more likely to have NSN tumor involvement and had a greater total number of tumor-involved nodes than patients without ECE of the SN metastasis. Increasing size of the SN metastasis and increasing size of the primary tumor, examined as continuous variables, were associated with an increased likelihood of NSN tumor involvement on univariate analysis. However, only ECE of the SN metastasis was associated with NSN tumor involvement on multivariate analysis.

CONCLUSIONS

ECE of the SN metastasis is a strong predictor of NSN tumor involvement. All patients with ECE of the SN metastasis should undergo mandatory completion ALND.

Ultrasonographically-guided fine-needle aspiration of axillary lymph nodes: role in breast cancer management

The knowledge of the status of axillary lymph nodes (LN) of patients with breast cancer is a fundamental prerequisite in the therapeutic decision. In the present work, we evaluated the impact of fine-needle aspiration cytology (FNAC) of ultrasonographically (US) selected axillary LN in the diagnosis of LN metastases and subsequently in the treatment of patients with breast cancer. Axillary US was performed in 298 patients with diagnosed breast cancer (267 invasive carcinomas and 31 ductal carcinoma in situ DCIS), and in 95 patients it was followed by FNAC of US suspicious LN. Smears were examined by routine cytological staining. Cases of uncertain diagnosis were stained in immunocytochemistry (ICC) with a combination of anticytokeratin and anti-HMFG2 antibodies. Eighty-five FNAC were informative (49 LN were positive for metastases, 36 were negative). In 49 of 267 patients with invasive breast carcinoma (18%), a preoperative diagnosis of metastatic LN in the axilla could be confirmed. These patients could proceed directly to axillary dissection. In addition, US-guided FNAC presurgically scored 49 out of 88 (55%) metastatic LN. Of all others, with nonsuspicious LN on US (203 cases including 31 DCIS), in which no FNAC examination was performed, 28 invasive carcinomas (16%) turned out to be LN positive on histological examination. Based on these data, US examination should be performed in all patients with breast cancer adding ICC-supported FNAC only on US-suspect LN. This presurgical protocol is reliable for screening patients with LN metastases that should proceed directly to axillary dissection or adjuvant chemotherapy, thus avoiding sentinel lymph node biopsy.

Complete sectioning of axillary sentinel nodes in patients with breast cancer. Analysis of two different step sectioning and immunohistochemistry protocols in 246 patients

AIMS

To evaluate two detailed step sectioning protocols for sentinel lymph nodes (SLNs).

METHODS

After vital dye or combined dye and radiocolloid guided biopsy, SLNs were fixed in formalin and embedded in paraffin wax. In protocol A, SLNs from 123 patients were sectioned in steps of 50-100 micro m, whereas in protocol B, SLNs from 123 patients were sectioned at steps of 250 micro m. Epithelial marker immunohistochemistry (IHC) was performed on multiple levels in cases with negative haematoxylin and eosin findings.

RESULTS

In groups A and B, 74 and 47 patients were found to have tumour cells in their axillary SLNs, and 19 (28%) and 18 (19%) patients, respectively, were upstaged as compared with the standard histological assessment. Nodal involvement detected by deeper sections was often micrometastatic or in isolated tumour cells

CONCLUSIONS

Serial sectioning and IHC are recommended for the evaluation of SLNs. The optimal extent of the histopathological work up should be studied further.

Non-sentinel lymph node involvement in patients with breast cancer and sentinel node micrometastasis; too early to abandon axillary clearance

AIMS

It has been suggested that patients with T1-2 breast tumours and sentinel node (SLN) micrometastases, defined as foci of tumour cells smaller than 2 mm, may be spared completion axillary lymph node dissection because of the low incidence of further metastatic disease. To gain insight into the extent of non-sentinel lymph node (n-SLN) involvement, SLNs and complementary axillary clearance specimens in patients with SLN micrometastases were examined.

METHODS

A set of 32 patients with SLN micrometastases was selected on the basis of pathology reports and review of SLNs. Five hundred and thirteen n-SLNs from the axillary clearance specimens were serially sectioned and analysed by means of immunohistochemistry for metastatic disease. Lymph node metastases were grouped as macrometastases (> 2 mm), and micrometastases (< 2 mm), and further subdivided as isolated tumour cells (ITCs) or clusters.

RESULTS

In 11 of 32 patients, one or more n-SLN was involved. Grade 3 tumours and tumours > 2 cm (T2-3 v T1) were significantly associated with n-SLN micrometastases as clusters (grade: odds ratio (OR), 8.3; 95% confidence interval (CI), 1.4 to 50.0; size: T2-3 tumours v T1: OR, 15; 95% CI, 2.18 to 103.0). However, no subgroup of tumours with regard to size and grade was identified that did not have n-SLN metastases.

CONCLUSIONS

In patients with breast cancer and SLN micrometastases, n-SLN involvement is relatively common. The incidence of metastatic clusters in n-SLN is greatly increased in patients with T2-3 tumours and grade 3 tumours. Therefore, axillary lymph node dissection is especially warranted in these patients. However, because n-SLN metastases also occur in T1 and low grade tumours, even these should be subjected to routine axillary dissection to achieve local control.

Completion axillary lymph node dissection minimizes the likelihood of false negatives for patients with invasive breast carcinoma and cytokeratin positive only sentinel lymph nodes

OBJECTIVE

To document the incidence of metastatic disease in complete axillary lymph node dissections (CALND) of patients with invasive carcinoma after a sentinel lymph node (SLN) biopsy, positive only by immunohistochemical staining for cytokeratin (CK-IHC).

METHODS

Sections of all SLNs, negative by routine histology, were immunostained and examined for cytokeratin positive cells. Sections of lymph nodes from CALND specimens were interpreted using routine hematoxylin and eosin (H&E) staining.

RESULTS

A total of 409 patients (29.6%) had metastatic disease in at least one sentinel lymph node on H&E examination. Of 971 H&E negative patients, 78 (8.0%) were positive only by CK-IHC. Sixty-two of the CK-IHC positive only patients underwent CALND. Nine of these 62 patients (14.5%) had metastases identified in the CALND specimen.

CONCLUSIONS

Because 14.5% of patients with invasive breast cancer and SLNs positive only by CK-IHC were found to have H&E positive lymph nodes on CALND, we conclude first, that CK-IHC should be used to evaluate SLNs, and second, that CALND should be considered when SLNs are positive by CK-IHC only. This approach will result in an absolute reduction of the false negative rate (absolute false negative rate reduced by 2.6% in our series).

Sentinel lymph node biopsy in breast cancer

The concept of sentinel lymph node (SLN) biopsy in breast cancer patients is simple, attractive and rapidly emerging as a new standard of care. Several aspects of the technique of lymphatic mapping, case selection, pathologic analysis and the finding of micrometastases, and the accuracy of the technique are important subjects of study and debate in the literature and will be discussed in this review. High identification rates can be attained by the use of both radioguided and blue dye lymphatic mapping. Intradermal injection of tracers has reported to be successful, suggesting that dermal and parenchymal lymphatics drain to the same SLN. Extra axillary drainage is only seen after peri- or intratumoural injection. SLN biopsy is most widely used for both palpable and non-palpable T1 and T2 tumours, and limited experience exists for other indications. Accuracy is high only in experienced hands. The impact of failure of the procedure on regional disease control and survival will be assessed in a trial of the NSABP (National Adjuvant Breast and Bowel Project). The influence of a positive SLN biopsy with and without axillary dissection on survival and local control will be studied in trials of the BASO (British Association of Surgical Oncology), ACOSOG (American College of Surgeons Oncology Group) and EORTC (European Organisation for Research and Treatment of Cancer). These phase III trials and related studies on the importance of micrometastases in the SLN will give new insights in the safety of the SLN procedure and in the importance of treatment of regional lymph nodes in relation to local disease control and survival.

Sentinel nodal assessment in patients with carcinoma of the lung

BACKGROUND

Assessment of sentinel nodes to predict metastases in a regional nodal basin is valuable for staging patients with melanoma and breast carcinoma. This study tested whether injection of isosulfan blue and technetium-99 could identify mediastinal sentinel nodes in patients with lung carcinoma and determine whether sentinel node histology predicts distal nodal metastases.

METHODS

Isosulfan blue and technetium-99 were injected into the tumor and pulmonary resection performed. The hilum and mediastinum were assessed visually and with the gamma probe, and a mediastinal nodal dissection was performed.

RESULTS

Thirty-one patients were evaluated. Three patients had positive sentinel nodes and positive distal mediastinal nodes. Twenty-two patients had negative sentinel nodes and negative distal nodes. No sentinel node was identified in 6 patients and 2 patients had two sentinel nodes.

CONCLUSIONS

These data demonstrate that this rapid, simple technique can identify sentinel nodes in the mediastinum and that the sentinel node is an accurate predictor of distal nodal metastases in patients with lung cancer.

Axillary lymph-node dissection for positive sentinel nodes in breast cancer patients

AIM

The aim was to identify a subset of breast cancer patient with positive sentinel nodes (SNs) for whom secondary axillary clearance would be unnecessary.

METHODS

Between March 1999 and May 2001, 288 patients with T0-T2 breast cancer less than 3cm in diameter had SN detection either by a colorimetric method or using a combined technique. SNs were stained with haematoxylin and eosin (H&E). For all negative SNs, serial sections and immunochemistry (IHC) were performed. All patients with positive SNs underwent a complete axillary lymph node dissection. One hundred and twenty patients were SN positve.

RESULTS

Non-sentinel node positivity (NSNP) was closely associated with the size of the tumour (14.3%, 54.1% and 51.8% for pT1a-b, pT1c and pT2 tumours respectively) and with the size of the SN metastasis: 15.9% IHC detected micrometastasis, 33.3% and 78.8% micro- and macrometastasis detected with H&E staining respectively. NSNP was found in 24.0% and 42.8% of patients with pT1c breast cancer and with micrometastasis detected by IHC and H&E staining. The node positivity rate reached 81.1% for pT1c lesions with macrometastasis in the SN. For the patients with pT2 breast cancer, these rates were 12.5% (IHC), 28.5% (H&E) 91.1% (macrometastasis).

CONCLUSIONS

We are unable to isolate precisely a subset of patients for whom total axillary lymph node dissection would be unnecessary. A subset of 14 small tumours (<1cm diameter) demonstrated micrometastases in the SN without NSNP.