Sentinel lymph node biopsy in multicentric breast cancer. The experience of the European Institute of Oncology

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.

Conservative surgery for multifocal/multicentric breast cancer

Multifocal (MF) and multicentric (MC) breast cancer is regularly considered a relative contraindication for breast-conserving therapy (BCT). There are two reasons for this wide spread notion: However, we concur that if optimal 'cytoreductive surgery' is achieved this will result in good local control (i.e. in-breast relapse <10% at 10 years). This can only be achieved on the basis of the right imaging, image guidance for non-palpable foci, and tumor free (invasive as well as ductal carcinoma in situ) margins after adequate pathological assessment. Surgery must then be followed by whole breast irradiation and systemic treatments as indicated by primary cancer biology. Careful planning and adaptive application of oncoplastic techniques will result in an optimal cosmetic results. The meticulous work of Roland Holland and coworkers(1) in the early 1980's on whole breast specimen showed invasive foci at more then 2 cm distance from the invasive primary cancer in more then 40% of specimen. Although multiple tumor foci may occur in up to 60% of mastectomy specimens, equivalent survival outcomes were observed in prospective trials comparing BCT and mastectomy for clinically unifocal lesions, suggesting that the majority of these foci are not, or do not become, biologically relevant or clinically significant with appropriate treatment. As diagnostic tools advance, MF and MC tumors are more commonly diagnosed. Cancers that previously would have been classified as unifocal now can be detected as MF or MC. In addition, locoregional treatment modalities have improved significantly over the past decade. More recent studies reflect these advances in diagnosis and treatment. Studies evaluated staging MRI showed that up to 19% of woman with diagnosed breast cancer harbor a second malignant ipsilateral lesion. These findings should only have consequences when additional lesions are proven cancer. Multiple enhancing lesions on MRI are in itself not an indication for a mastectomy. The Z0011 trial and the AMAROS trial demonstrated a similar phenomenon for axillary treatment; less surgery does not necessarily lead to inferior local control or survival outcomes. Recent studies supplement the growing evidence that treatment of patients with MF/MC breast cancer with BCS, radiotherapy, and adjuvant systemic therapy can result in low rates of in-breast recurrence.

[Sentinel lymph node-multicentric and multifocal tumors: a valid technique?]

Sentinel node biopsy without complementary axillary lymph node dissection was validated for T1-2 N0 unifocal breast cancer without previous treatment since several years. In the situation of multifocal multicentric breast tumors, this procedure was considered as a contraindication. The aim of this work was to analyse literature results to determine if sentinel lymph node biopsy can be considered as a valid option without complementary axillary lymph node dissection for negative sentinel lymph node.

[Relevance of the sentinel lymph node biopsy in breast multifocal and multicentric cancer]

OBJECTIVES

The sentinel lymph node biopsy is a gold standard in the management of breast cancer. Its role in multifocal or multicentric tumors is still evolving. The aim of this study is to assess the feasibility and pertinence of sentinel lymph node biopsy in multifocal and multicentric tumors based on a systematic review of literature.

METHODS

A systematic review was conducted searching in the following electronic databases PubMed using "sentinel lymph node biopsy", "breast cancer", "multifocal tumor", "multicentric tumor" and "multiple tumor" as keywords. We included original articles published between 2000 and 2014, both French and English, studying feasibility of sentinel lymph node biopsy in invasive breast cancer, multicentric and/or multifocal tumors. The first end point was success rate and false negative rate.

RESULTS

Twenty-six articles were included in this literature review, with 2212 cases (782 multifocal, 737 multicentric and 693 multiple tumors). Percentage of tumors whose stage was higher than stage T2 ranged from 0 to 86.3%. Success rate average was 83.1%. False negative average was 8.2%. False negative rate was less than 10% in 15 articles. Mean of sentinel lymph node biopsy was 2 (1-9). The average rate of sentinel lymph node positive was 50.6%. Axillary recurrence rate was 0.5%.

CONCLUSION

Despite the methodological biases of the studies included in this review of literature, the false negative rate of sentinel node biopsy in multifocal and multicentric breast cancers are less than 10% with a low rate of axillary recurrence. Despite the lack of randomized study, this procedure can be routinely performed in accordance with rigorous technical process.

Extent of primary breast cancer surgery: standards and individualized concepts

Surgery is still a main therapeutic option in breast cancer treatment. Nowadays, methods of resection and reconstruction vary according to different tumors and patients. This review presents and discusses standards of care and arising questions on how radical primary breast cancer surgery should be according to different clinical situations. In most early breast cancer patients, breast conservation is the method of choice. The discussion on resection margins is still controversial as different studies show conflicting results. Modified radical mastectomy is the standard in locally advanced breast cancer patients, although there are different promising approaches to spare skin or even the nipple-areola complex. A sentinel node biopsy is the standard of care in clinically node-negative invasive breast cancer patients, whereas the significance of axillary lymphonodectomy seems to be questioned through a number of different findings. Although there are interesting findings to modify surgical approaches in very young or elderly breast cancer patients, it will always be an individualized approach if we do not adhere to current guidelines. Up to date, there are no special surgical procedures in BRCA mutation carriers or patients of high-risk families.

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.

Sentinel Lymph Node Biopsy in Early Breast Cancer: The Experience of the European Institute of Oncology in Special Clinical Scenarios

BACKGROUND: While axillary nodal status is still one of the most important prognostic factors in breast cancer, sentinel lymph node biopsy (SLNB) has evolved as a main procedure to strongly reduce postsurgical morbidity improving early and long-term quality of life. MATERIAL AND METHODS: Between 1996 and 2010, we performed 18,884 SLNBs for breast cancer, successfully confirming the validity of this technique and its positive impact on patients' quality of life, even though decision-making processes for adjuvant treatment strongly depend on biological features. RESULTS: This paper summarizes published data mainly collected in our institute considering special clinical scenarios such as ductal intraepithelial neoplasia, intramammary sentinel nodes, multicentric breast cancer, prior breast surgery, previous breast aesthetic surgery, second axillary SLNB, pregnant patients, primary chemotherapy, and male patients. CONCLUSIONS: In general, we believe that SLNB represents the standard procedure for axillary staging in virtually all clinical situations, even in those which were previously considered a contraindication for this procedure. At the moment, the only contraindication to SLNB is the presence of documented axillary metastases.

Accuracy of sentinel lymph node biopsy in large and multifocal/multicentric breast carcinoma--a systematic review

BACKGROUND

While sentinel lymph node biopsy (SLNB) is established in the management of small unifocal breast cancer its role in management of multifocal (MF), multicentric (MC) and larger tumors is still evolving.

METHODS

Medline was searched; studies meeting pre-determined criteria were included. Data were extracted and entered into evidence tables.

RESULTS

Twenty six studies met inclusion criteria and reported data on accuracy; no randomized trials were identified. For MF cancers (n = 314 cases), success rate for identification of an SLN was 86-94%, SLN positivity rate 42-59%, false negative rate (FNR) 0-33% and overall accuracy 78-100%. For MC (n = 294 cases): success rate 92-100%, SLN positivity rate 25-61%, FNR 4-8% and accuracy 96-100%. For 'multiple breast cancer' (studies combining MF/MC cases; n = 996 cases): success rate 92-100%, SLN positivity rate 12-63%, FNR 0-25%, and accuracy 82-100%. For larger tumors (n = 1912 cases): success rate 86-100%, SLN positivity rate 49-77%, FNR 3-18% and accuracy 85-98%. For MC/MF and larger cancers overall non-SLN positivity rates were up to 82%; axillary recurrence rates were low but seldom reported.

CONCLUSION

There are no randomized trials evaluating the safety of SLNB in MF/MC and larger breast cancers. Based on limited evidence, success rate and FNR appear to be similar to those for small unifocal cancers, however node positivity rates are higher and rates of non-SLN positivity are very high. Awareness of these issues is essential when recommending SLNB based axillary management for these higher-risk tumors.

[Surgery for invasive breast cancer]

As most solid tumors, surgery is often the first step of the multidisciplinary management for breast cancers. Although mastectomy and axillar lymphadenectomy still have indications, conservative treatment and sentinel node detection are commonly used. Thanks to induction chemotherapy and oncoplastic techniques, surgery is conservative in most cases, even for important tumors without overall survival prejudice. There is no consensus about resection margins status but a limit of 2 to 3 mm seems to be reasonable while oncoplastic surgery allows large resection and good cosmetic outcomes. In this overview, we present the state of the art for breast cancer surgery including conservative and radical treatments, axillar lymphadenectomy and sentinel lymph node detection, margins status, oncoplastic techniques.

Oncological and aesthetic considerations of conservational surgery for multifocal/multicentric breast cancer

Conventional indications for mastectomy (MX) reflect circumstances where breast conserving therapy (BCT) could compromise oncological or cosmetic outcome. MX continues to be recommended for the majority of women with multiple lesions within the same breast. In this article, we review the oncological safety and aesthetic considerations of BCT in the context of multifocal (MF) or multicentric (MC) breast cancer. Literature review facilitated by Medline and PubMed databases. Published studies have reported divergent results regarding the oncological adequacy of BCT in the management of MF or MC disease. Earlier studies demonstrated high rates of local recurrence (LR) for BCT. More recent series have found BCT to be comparable to MX in terms of LR, distant failure, disease free and overall survival. Few studies have adequately evaluated cosmetic outcomes following BCT for MF or MC breast cancer. Contemporary oncoplastic techniques have extended the clinical utility of BCT and are of particular relevance to breast conservation in the context of MF or MC lesions. Appropriate case selection, preoperative oncological and aesthetic planning, satisfactory clearance of the surgical margins and adjuvant radiotherapy are of paramount importance. In the absence of level-1 guidance concerning the management of women with MF or MC disease, each case requires discussion with regard to tumor and patient related factors in the context of the multidisciplinary team. In selected patients with MF or MC disease, BCT is oncologically safe and cosmetically acceptable. Uniformity of practice and the establishment of a standard of care will require an evidence-base from prospective studies.

Recent advances in the surgical care of breast cancer patients

A tremendous improvement in every aspect of breast cancer management has occurred in the last two decades. Surgeons, once solely interested in the extipartion of the primary tumor, are now faced with the need to incorporate a great deal of information, and to manage increasingly complex tasks.

As a comprehensive assessment of all aspects of breast cancer care is beyond the scope of the present paper, the current review will point out some of these innovations, evidence some controversies, and stress the need for the surgeon to specialize in the various aspects of treatment and to be integrated into the multisciplinary breast unit team.

False negative rate of sentinel lymph node biopsy in multicentric and multifocal breast cancers may be higher in cases with large additive tumor burden

We aimed to evaluate the feasibility of sentinel lymph node biopsy (SLNB) in multicentric/ multifocal breast cancer. In this prospective study, 23 women with multicentric/multifocal breast cancer underwent SLNB at our institution from April 2002 to February 2006. Presence of preoperative axillary metastases was confirmed by FNA. Patients underwent sub-areolar radiopharmaceutical injection +/- isosulfan blue to perform SLNB, then completion ALND. The false-negative (FN) rate of SLNB was determined based upon final pathology. Twenty women with multicentric and three with multifocal invasive carcinoma were enrolled. The SLN identification rate was 100%. The overall FN rate of SLNB was 15% (95% CI 0.0466, 0.4281). Both cases with FN SLNB had multicentric disease, pathologic stage III breast cancer and a larger tumor burden compared with the study population. SLNB using sub-areolar injection is feasible for patients with multicentric/multifocal breast cancer yet may be associated with a higher FN rate in patients with large additive tumor burden.

Current surgery for breast cancer

Surgeons retain the central role in the multidisciplinary care of the breast cancer patient. While technical details of the operations for these patients remain important, effective evidence-based decision making may be even more so. Advances in the methods of breast cancer diagnosis, localization techniques and surgical therapies, as well as the expanded role of the surgeon in breast cancer prevention, radiation therapy and the treatment of distant disease, requires surgeons to stay up to date with the available evidence. Herein, we present a review of the current surgical therapy of invasive breast cancer.

Axillary metastases in breast cancer patients with negative sentinel nodes: a follow-up of 3548 cases

PREMISES: Sentinel node biopsy (SNB) in patients with breast carcinoma accurately predicts the axillary node status. However, in some 4-7% of patients with negative sentinel nodes, the remaining axillary nodes harbour cancer cells.

OBJECTIVE

Our purpose was the long-term observation of a large number of patients who did not receive axillary dissection after a negative sentinel node biopsy, in order to evaluate the incidence of overt axillary metastases.

METHODS

Patients (3548) treated from 1996 to 2004, with negative sentinel nodes not submitted to axillary dissection, were followed up to 11 years with a median follow-up of 48 months.

RESULTS

Three hundred and sixteen unfavourable events occurred among the 3548 patients, 196 of which (5.5%) related to primary breast carcinoma. Thirty one cases of overt axillary metastases were found (0.9%): they received total axillary dissection and 27 of them are at present alive and well. The 5-year overall survival rate of the whole series was 98%.

CONCLUSIONS

Patients with negative sentinel node biopsy not submitted to axillary dissection show, at follow-up, a rate of overt axillary metastases lower than expected.

Sentinel lymph node biopsy in patients with multicentric/multifocal breast cancer: low false-negative rate and lack of axillary recurrence

BACKGROUND

Accuracy of sentinel lymph node biopsy (SLNB) and rate of axillary recurrence in multicentric/multifocal (MC/MF) breast cancer are reported.

METHODS

From 1999 to 2006, 93 patients with MC/MF breast cancer underwent SLNB; 41 underwent axillary lymph node dissection regardless of SLN pathology (group 1), and 52 underwent axillary lymph node dissection only if an SLN was positive (group 2). Patient demographics, SLN techniques, and pathology were recorded.

RESULTS

There were no differences between the 2 groups with respect to patient age; tumor size, grade, stage, and histology; or method of SLN detection. The incidence of axillary metastasis was greater in group 1 patients (68%) compared with group 2 patients (12%) (P < .01). In group 1, the sensitivity and specificity of SLNB were 93% and 100%, respectively, with a false-negative rate of 7%. None of the 52 patients in group 2 experienced axillary recurrence (median follow-up 4.8 years).

CONCLUSIONS

The accuracy of SLNB in MC/MF breast cancer is comparable with that observed in unifocal breast cancer. Despite a lower rate of SLN positivity in patients undergoing SLNB only, axillary recurrence was not observed.

Intraoperative frozen section assessment of sentinel lymph nodes in the operative management of women with symptomatic breast cancer

BACKGROUND

Maximisation of the potential of sentinel lymph node biopsy as a minimally invasive method of axillary staging requires sensitive intraoperative pathological analysis so that rates of re-operation for lymphatic metastases are minimised. The aim of this study was to describe the test parameters of the frozen section evaluation of sentinel node biopsy for breast cancer compared to the gold standard of standard permanent pathological evaluation at our institution.

METHODS

The accuracy of intraoperative frozen section (FS) of sentinel nodes was determined in 94 consecutive women undergoing surgery for clinically node negative, invasive breast cancer (37:T1 disease; 43:T2; 14:T3). Definitive evidence of lymphatic spread on FS indicated immediate level II axillary clearance while sentinel node "negativity" on intraoperative testing led to the operation being curtailed to allow formal H&E analysis of the remaining sentinel nodal tissue.

RESULTS

Intraoperative FS correctly predicted axillary involvement in 23/30 patients with lymphatic metastases (76% sensitivity rate) permitting definitive surgery to be completed at the index operation in 87 women (93%) overall. All SN found involved on FS were confirmed as harbouring tumour cells on subsequent formal specimen examination (100% specificity and positive predictive value) with 16 patients having additional non-sentinel nodes found also to contain tumour. Negative Predictive Values were highest in women with T1 tumours (97%) and lessened with more local advancement of disease (T2 rates: 86%; T3: 75%). Of those with falsely negative FS, three had only micrometastatic disease.

CONCLUSION

Intraoperative FS reliably evaluates the status of the sentinel node allowing most women complete their surgery in a single stage. Thus SN can be offered with increased confidence to those less likely to have negative axillae hence expanding the population of potential beneficiaries.

Conservative surgery in patients with multifocal/multicentric breast cancer

PURPOSE

Many physicians recommend mastectomy in case of multifocal (MF) or multicentric (MC) breast cancer due to a theoretical risk of poor local control with less extensive surgery. We retrospectively evaluate outcome of patients with MF/MC cancers who had breast conservation with specific attention on local control and predictive factors of recurrence.

PATIENTS AND METHODS

Four hundred and seventy six patients with either MF (n = 421) or MC (n = 55) breast cancer, underwent breast-conserving surgery between 1997 and 2002 in a single institution. Median follow up was 73 months (range 11-118).

RESULTS

Median age was 53 years (range 23-86). Invasive lobular carcinoma was found in 88 patients (18.5%) and mixed ductal-lobular cancer in 27 (5.7%) patients. Two hundred and sixty-seven patients (76.7%) had two identified tumor foci, 55 patients (15.3%) had three and 29 patients (8.0%) had four or more. Two hundred and sixty-one patients (55.3%) had nodal involvement. The 5-year cumulative incidence of local relapse was 5.1%. At the multivariate analysis, over-expression of HER2/neu and lack of both estrogen and progesterone receptors (HR: 3.2, 95% C.I. 1.01-10.0, and HR: 2.7, 95% C.I. 1.06-7.7, respectively) were associated with a higher ipsilateral breast cancer reappearance rate. Involvement of four or more lymph nodes and lack of estrogen and progesterone receptors (HR: 2.7, 95% C.I. 1.06-6.7, and HR: 4.7, 95% C.I. 2.1-10.4, respectively) were associated with poorer overall survival.

CONCLUSIONS

In selected patients with MF/MC breast cancer, wide conservative surgery is not associated with poor local disease control and can be considered whenever acceptable cosmetic results can be achieved.

Sentinel node biopsy in patients with multiple breast cancer

BACKGROUND

Multicentric or multifocal breast cancer is considered a limitation for sentinel lymph node biopsy (SLNB). Studies showing that all quadrants of the breast drain via common afferent lymphatic channels indicate that multiple tumors do not affect lymphatic drainage. We therefore assessed the accuracy of SLNB in patients with multiple breast tumors.

METHODS

Of the 942 breast cancer patients who underwent SLNB using radioisotope at Asan Medical Center between January 2003 and December 2006, 803 had unifocal and 139 had multiple tumors. Axillary dissection after SLNB was performed on 884 patients, 757 with unifocal and 127 with multiple tumors. All patients underwent lymphatic scintigram for removal of sentinel lymph nodes (SLNs). The clinical characteristics and accuracy of SLNB was compared in patients with unifocal and multiple breast cancer.

RESULTS

In the multiple tumor group, 2.68 +/- 0.84 SLNs were identified in 136 of 139 patients (identification rate, 97.84%); 81.5% of SLNs were identified by scintigram. The incidence of axillary metastases was 29.50% (41/139). SLNB accuracy was 97.63% (124/127), with a false negative (FN) rate of 7.89% (3/38). In the unifocal group, 2.67 +/- 0.96 SLNs were identified in 787 of 803 patients (identification rate, 98.00%); 84.8% of SLNs were identified by scintigram. The incidence of axillary metastasis was 22.04% (177/803). SLNB accuracy was 98.02% (742/757), with a FN rate of 8.62% (15/174). The accuracy and FN rate of SLNB did not differ significantly between unifocal and multiple breast cancer.

CONCLUSION

The accuracy of SLNB in multiple breast cancer is comparable to its accuracy in unifocal cancer. These findings indicate that SLNB can be used an as alternative to complete axillary lymph node dissection in patients with multiple breast tumors.

Sentinel lymph node biopsy in multiple breast cancer using subareolar injection of the tracer

We performed subdermal injection of (99m)Tc-labelled albumin combined with subareolar (SA) injection of blue dye to axillary lymphatic mapping and sentinel lymph node biopsy (SLNB) in patients with multifocal and multicentric breast cancer to evaluate the feasibility and accuracy of this technique. A retrospective analysis of our experience on 235 SLNB showed that 30(12.7%) had multiple cancer (MC) on final pathologic examination and was considered in relation to the aim of the study. Mean age was 57.19 years (range 24-90). Mean number of SLNs identified was 1.93 (range 1-5). Mean number of axillary LNs examined was 18.10 (range 12-27). Overall successful identification was 100% with a false negative (FN) rate of 6.25%. Overall accuracy of lymphatic mapping and sensitivity was 96.6% and 93.7%, respectively. SLNB using the SA injection technique may be an alternative to complete axillary dissection in patients with multiple breast cancers and a clinically negative axilla.

Contraindications of sentinel lymph node biopsy: are there any really?

BACKGROUND

One of the most exciting and talked about new surgical techniques in breast cancer surgery is the sentinel lymph node biopsy. It is an alternative procedure to standard axillary lymph node dissection, which makes possible less invasive surgery and side effects for patients with early breast cancer that wouldn't benefit further from axillary lymph node clearance. Sentinel lymph node biopsy helps to accurately evaluate the status of the axilla and the extent of disease, but also determines appropriate adjuvant treatment and long-term follow-up. However, like all surgical procedures, the sentinel lymph node biopsy is not appropriate for each and every patient.

METHODS

In this article we review the absolute and relative contraindications of the procedure in respect to clinically positive axilla, neoadjuvant therapy, tumor size, multicentric and multifocal disease, in situ carcinoma, pregnancy, age, body-mass index, allergies to dye and/or radio colloid and prior breast and/or axillary surgery.

RESULTS

Certain conditions involving host factors and tumor biologic characteristics may have a negative impact on the success rate and accuracy of the procedure. The overall fraction of patients unsuitable or with multiple risk factors that may compromise the success of the sentinel lymph node biopsy, is very small. Nevertheless, these patients need to be successfully identified, appropriately advised and cautioned, and so do the surgeons that perform the procedure.

CONCLUSION

When performed by an experienced multi-disciplinary team, the SLNB is a highly effective and accurate alternative to standard level I and II axillary clearance in the vast majority of patients with early breast cancer.