The value of cytokeratin immunohistochemistry in the evaluation of axillary sentinel lymph nodes in patients with lobular breast carcinoma

BACKGROUND: Cytokeratin immunohistochemistry (IHC) reveals a higher rate of occult lymph node metastases among lobular carcinomas than among ductal breast cancers. IHC is widely used but is seldom recommended for the evaluation of sentinel lymph nodes in breast cancer patients. Objective: To assess the value of cytokeratin IHC for the detection of metastases in sentinel lymph nodes of patients with invasive lobular carcinoma. METHODS: The value of IHC, the types of metastasis found by this method, and the involvement of non-sentinel lymph nodes were analysed in a multi-institutional cohort of 449 patients with lobular breast carcinoma, staged by sentinel lymph node biopsy and routine assessment of the sentinel lymph nodes by IHC when multilevel haematoxylin and eosin staining revealed no metastasis. RESULTS: 189 patients (42%) had some type of sentinel node involvement, the frequency of this increasing with increasing tumour size. IHC was needed for identification of 65 of these cases: 17 of 19 isolated tumour cells, 40 of 64 micrometastases, and 8 of 106 larger metastases were detected by this means. Non-sentinel-node involvement was noted in 66 of 161 cases undergoing axillary dissection. Although isolated tumour cells were not associated with further lymph node involvement, sentinel node positivity detected by IHC was associated with further nodal metastases in 12 of 50 cases (0.24), a proportion that is higher than previously reported for breast cancer in general. CONCLUSIONS: IHC is recommended for the evaluation of sentinel nodes from patients with lobular breast carcinoma, as the micrometastases or larger metastases demonstrated by this method are often associated with a further metastatic nodal load.     

Breast epithelial cells in dermal angiolymphatic spaces: a manifestation of benign mechanical transport

Evidence suggesting that breast epithelial cells may reach axillary lymph nodes by benign mechanical transport (BMT), rather than metastatic means, has been recently reported. We report a case of a patient with ductal carcinoma in situ of the breast, who had displaced epithelial elements in the mastectomy specimen, dermal angiolymphatic spaces, and a sentinel lymph node. We attribute the epithelial aggregates in the dermal angiolymphatic spaces and a single cell in the sentinel lymph node to BMT, based on the clinicopathological findings of the case. We, therefore, suggest that the effects of BMT be considered in the differential diagnosis of epithelial aggregates in dermal angiolymphatic spaces in the appropriate clinicopathological setting.     

Sentinel lymph node biopsy in breast cancer: creating controversy and defining new standards

Sentinel lymph node (SLN) biopsy is an exciting and promising new addition to surgical management and pathologic evaluation of breast cancer. Sentinel nodes are more likely to contain metastases than nonsentinel nodes providing an opportunity to more accurately stage breast cancer patients. In the future, surgical management of the axilla may be approached as a staged procedure, perhaps eliminating axillary dissection in SLN-negative patients, should clinical trials demonstrate the safety of this approach. The advent of SLN biopsy has propelled an old question back to the forefront of clinical investigation: do occult metastases in lymph nodes have prognostic, predictive, and clinical significance? This article provides one opinion and a review on the pathology and future of SLN biopsy in breast cancer. Practicing pathologists will need to stay abreast of the issues and facts in order to participate in the debate and shape the future of pathologic management of sentinel nodes.     

Anatomo-pathologic study of sentinel lymph nodes in melanoma. Analysis of 200 cases

Pathologic evaluation of sentinel lymph node represents a new technique for managing high-risk primary melanoma. We examined the sentinel lymph node biopsies of 200 patients affected by primary melanomas of trunk, limbs, head and neck, who had been operated at "M. Bufalini" Hospital between April 1996 and July 1998. The lymphatic mapping has been performed through the preoperative intradermal injection of vital blue dye and technetium-labelled albumin. 319 sentinel lymph nodes were harvested and the 11.3% (15% of patients) were positive for melanoma metastases. No metastases were found in melanomas < or = 1 mm. The percentage of positive sentinel lymph nodes in patients with melanomas > 1 mm in thickness was 16.3% (22% of patients). In 5 cases (2.5%) nodal nevi were found, 1 of which was associated with micrometastasis. All 30 patients with positive sentinel lymph nodes underwent regional lymph node dissection and 555 lymph nodes were harvested. Melanoma metastases were found in only 7 patients, in 31 lymph nodes. The procedure of SLN detection and biopsy is a feasible surgical approach to melanoma patients. It is extremely useful in finding early metastases and in effective pathologic staging. As a consequence of the very low incidence of metastases in the sentinel lymph nodes of patients with thin melanomas, we suggest the sentinel lymph node mapping should be offered to patients with primary melanomas at least 1 mm in depth.     

Assessment of sentinel lymph nodes for breast cancer

Sentinel lymph node biopsy is standard of care for assessment of lymph node stage in early breast cancer in patients with clinically negative nodes. The limited clinical significance of low volume axillary metastatic disease has led to changes in surgical management of the axilla with a shift away from routine axillary lymph node dissection if the sentinel lymph node is found to contain metastatic tumour. This has led to a decrease in the use of intraoperative assessment of sentinel nodes. Specimen handling and histological assessment of sentinel lymph nodes is described, with the emphasis on identification of macrometastatic disease defined as metastases greater than 2 mm. Routine levels and/or cytokeratin immunohistochemistry is not recommended. The increasing use of neoadjuvant chemotherapy and growing evidence that sentinel lymph node biopsy is safe and accurate in this setting, including in patients with proven node positive disease, has resulted in new challenges in the interpretation of these specimens.     

Intraoperative evaluation of axillary lymph nodes for micrometastases using immunohistochemistry--preliminary study

The increase of utilization of sentinel lymph nodes concept for breast carcinoma has made intraoperative evaluation of immunohistochemistry using epithelial markers attractive. At present the optimal procedures for intraoperative detection of micrometastasis of axillary lymph nodes has not been established. The purpose of this study is to evaluate the immunohistochemistry for intraoperative diagnosis of axillary lymph nodes in patients with breast cancer. Lymph nodes from 170 patients(1048 lymph nodes) were examined immunohistochemistry using anti cytokeratin, compared with intraoperative frozen section of same lymph nodes with H & E staining. Tumor metastases were found in 50 patients(92 lymph nodes) in H & E staining section, compared with 64 patients(113 lymph nodes) stained with anti-cytokeratin. Of 14 patients whose metastases were detected by immunohistochemistry. Routine intraoperative frozen diagnosis using H & E stainings significantly underestimates lymph nodes metastases. The insufficient diagnosis may be overcome by immunohistochemistry using anti-cytokeratin and careful examination of routine sections with good qualities. The true clinical significance of these micrometastases will be determined by long term follow up studies.     

Intraoperative evaluation of sentinel lymph nodes for breast carcinoma: current methodologies

Sentinel lymph node biopsy is an important new addition to the surgical management of patients with breast carcinoma. Sentinel nodes have a higher chance of containing metastases than do nonsentinel nodes. Sentinel lymph node biopsy provides an opportunity to stage breast carcinoma patients more accurately and to modify subsequent treatment. One of the most exciting current roles of sentinel lymph node biopsy is the ability to stage patients intraoperatively, allowing a one-step axillary lymph node dissection if the sentinel lymph node contains metastatic carcinoma. Currently, intraoperative evaluation of sentinel lymph nodes is performed using imprint cytology with or without rapid cytokeratin staining, frozen sectioning with or without rapid cytokeratin staining, scrape preparations, or some combination of these techniques. We review the relative strengths and weaknesses of these different methodologies. A great deal of controversy exists regarding the management of patients with metastatic breast carcinoma, particularly those patients with occult and micrometastatic disease. These issues are beyond the scope of this article.     

Evaluation of sentinel lymph nodes in breast cancer

Sentinel lymph node biopsy is an accurate method for the detection of axillary metastases in cases of breast carcinoma and is of value as a replacement for axillary dissection. There is variation, however, in the methods and protocols used for the histopathological evaluation of sentinel lymph nodes, standardisation of which will be required if results of sentinel lymph node analysis are to be used to stratify patients into prognostic groups. The significance of micrometastases, isolated tumour cells (ITCs) and the value of immunohistochemistry are also matters for further definition. In this Expert Opinion we present reviews from two authors, providing American and European perspectives on the approach to sentinel lymph node evaluation.     

Breast cancer metastasis through the lympho-vascular system

Breast cancer metastasizes through the lymphovascular system to the regional lymph nodes in the axilla and to both visceral and non-visceral sites. Renewed interest in the route by which tumor cells gain access to blood and lymphatic capillaries are the subject of research at mechanical, anatomic, pathologic, genetic, epidemiologic and molecular levels. Two papers presented at the 7th International Symposium on Cancer Metastasis in San Francisco showed tumor cells entering the systemic circulation through the sentinel lymph node. This information challenges the current paradigm where clinicians believe that access is gained through intra- and peri-tumoral blood vessels and that metastasis to axillary lymph nodes is an interesting epi-phenomenon. The sentinel lymph node era has changed the modern surgical approach to the axilla and the basis of this change is summarized in this paper. A new approach to the management of axillary metastases after systemic therapy relies on determining whether there is a complete pathologic response; if no tumor is found in the previously biopsied node, a complete axillary lymph node dissection may be avoided. African American women seem to inherit a trait from West African ancestors and tend to develop more lethal types of breast cancer. These tumors may have a molecular machinery that enhances their ability to metastasize to visceral sites and future research may unearth the mechanisms for this phenomenon.     

Prevalence of occult metastases in axillary sentinel lymph nodes of breast carcinoma

Recently, sentinel lymph node biopsy (SLNB) has been accepted as a standard method of assessment of axillary lymph nodes in breast cancer patients with no clinical lymphadenopathy. There is no standard pathologic method to evaluate sentinel lymph nodes. The purpose of this study is to evaluate the frequency of occult lymph node metastasis in sentinel lymph nodes via serial sectioning and immunohistochemical study with cytokeratin and its relationship with other clinicopathologic factors. Paraffin-embedded blocks of axillary sentinel lymph nodes of breast cancer patients, biopsied in 2005-2009 and reported as negative, were reviewed with 3 μm sections, H and E staining and immunohistochemical study with an epithelial cytokeratin marker. Clinicopathologic data and relapse, if occurred was recorded and its relationship with occult metastasis was statistically analyzed. Sixty-eight sentinel pathology blocks of 66 patients (65 women and one man, median age 49 years) were investigated. Four cases (5.8%) of occult metastases were found, one by HE staining, and three cases with IHC (1 micrometastasis, 2 isolated tumor cells). Accuracy of reported cases was 94.1% upon re-examination. Sixty-four patients were followed after surgery and adjuvant therapy (range: 6-38 months, median: 21 months). No relapse was reported. There was no significant statistical relationship between occult metastasis and disease-free survival. Although 4 cases (5.8%) of sentinel lymph nodes were positive in the complementary study, with a median follow-up of 21 months, we found no difference in disease-free survival between these patients and others. To show a significant, however small, difference, one needs further research with a greater number of patients and longer follow-up.     

Intraoperative evaluation of sentinel lymph nodes for metastatic breast carcinoma by imprint cytology.

BACKGROUND: The increasing utilization of lymphatic mapping techniques for breast carcinoma has made intraoperative evaluation of sentinel lymph nodes attractive. Axillary lymph node dissection can be performed during the initial surgery if the sentinel lymph node is positive, potentially avoiding a second operative procedure. At present the optimal technique for rapid sentinel lymph node assessment has not been determined. Both frozen sectioning and intraoperative imprint cytology are used for rapid intraoperative sentinel lymph node evaluation at many institutions. The purpose of this study is to evaluate experience with imprint cytology for intraoperative evaluation of sentinel lymph nodes in patients with breast cancer. METHODS: A retrospective review of the intraoperative imprint cytology results of 678 sentinel lymph node mappings for breast carcinoma was performed. Sentinel nodes were evaluated intraoperatively by either bisecting or slicing the sentinel node into 4 mm sections. Imprints were made of each cut surface and stained with H&E and/or Diff-Quik. Permanent sections were evaluated with up to four H&E stained levels and cytokeratin immunohistochemistry. Intraoperative imprint cytology results were compared with final histologic results. Results: The sensitivity of imprint cytology was 53%, specificity was 98%, positive predictive value was 94%, negative predictive value was 82% and accuracy was 84%. The sensitivity for detecting macrometastases (more than 2mm) was significantly better than for detecting micrometastases (相似文献   

Update on sentinel node pathology in breast cancer

Pathologic examination of the sentinel lymph nodes (SLNs) in patients with breast cancer has been impacted by the publication of practicing changing trials over the last decade. With evidence from the ACOSOG Z0011 trial to suggest that there is no significant benefit to axillary lymph node dissection (ALND) in early-stage breast cancer patients with up to 2 positive SLNs, the rate of ALND, and in turn, intraoperative evaluation of SLNs has significantly decreased. It is of limited clinical significance to pursue multiple levels and cytokeratin immunohistochemistry to detect occult small metastases, such as isolated tumor cells and micrometastases, in this setting. Patients treated with neoadjuvant therapy, who represent a population with more extensive disease and aggressive tumor biology, were not included in Z0011 and similar trials, and thus, the evidence cannot be extrapolated to them. Recent trials have supported the safety and accuracy of sentinel lymph node biopsy (SLNB) in these patients when clinically node negative at the time of surgery. ALND remains the standard of care for any amount of residual disease in the SLNs and intraoperative evaluation of SLNs is still of value for real time surgical decision making. Given the potential prognostic significance of residual small metastases in treated lymph nodes, as well as the decreased false negative rate with the use of cytokeratin immunohistochemistry (IHC), it may be reasonable to maintain a low threshold for the use of cytokeratin IHC in post-neoadjuvant cases. Further recommendations for patients treated with neoadjuvant therapy await outcomes data from ongoing clinical trials. This review will provide an evidence-based discussion of best practices in SLN evaluation.     

Genomic alterations in primary breast cancers compared with their sentinel and more distal lymph node metastases: An aCGH study

Metastatic potential of breast cancer may be associated with specific genomic alterations and the earliest metastases are likely to be found in the sentinel lymph nodes (SLN). Using array comparative genomic hybridization (aCGH), we compared the genomes of primary breast invasive duct carcinomas (IDCs), their sentinel and more distal lymph node metastases, and IDCs without nodal metastasis. Thirty‐three samples from 22 patients with IDC were subjected to aCGH: 8 IDC samples from patients without lymph node metastasis, 11 IDCs associated with SLN metastases out of which 7 had paired samples of metastases, and 14 samples of lymph node metastases out of which 8 were sentinel‐distal pairs from 4 patients. aCGH data were analyzed by correlation of genomic profiles, cluster analysis, segmentation, and peak identification. Quantitative real‐time PCR was used for data validation. We observed high genomic similarity between primary tumors and their nodal metastases as well as between metastases to the sentinel and distal lymph nodes. Several recurrent alterations were detected preferentially in IDC associated with SLN metastases compared to IDCs without metastasis. Amplification within the 17q24.1‐24.2(59.96–62.76 Mb) region was associated with presence of sentinel or distal lymph node metastases; larger tumor size and higher histological grade. In our samples, there were genomic events associated with metastatic progression, which could be detected in both primary tumors and LN metastases. Gain on 17q24.1‐24.2 is a candidate region for further testing as a predictor of nodal metastasis. © 2009 Wiley‐Liss, Inc.     

Expression of retinoblastoma protein in breast cancer metastases to sentinel nodes: evaluation of its role as a marker for the presence of metastases in non-sentinel axillary nodes, and comparison to p16INK4a.

The aim of this study was to evaluate the role of retinoblastoma protein (pRb), alone and in combination with p16, as a predictive marker for metastases in non-sentinel nodes in cases where the sentinel node showed metastatic breast carcinoma. Paraffin blocks of lymph nodes from 48 patients with metastatic breast carcinoma were immunostained with a monoclonal antibody to retinoblastoma protein (PharMingen). Results were compared with known prognostic parameters of the primary tumor, estrogen and progesterone receptor status, proliferation index, and p16 (DAKO) expression. Lymph nodes from 38 of the 48 (79%) cases were pRb positive. There was no correlation of pRb staining alone with the primary tumor parameters studied or the proliferative index of the metastatic tumor. In 16 patients with both a sentinel node biopsy and an axillary lymph node dissection, 8 (50%) had metastatic breast carcinoma. The sentinel nodes of three of these eight patients (38%) were pRb negative (positive predictive value of 60% vs. 73% for p16). The remaining eight patients (50%) had no metastases in non-sentinel nodes, even though their sentinel nodes had metastatic breast carcinoma; six of these eight patients (75%) were pRb positive (negative predictive value of 55% vs. 83% for p16). pRb and p16 staining results combined showed that pRb-negative/p16-positive cases were associated with non-sentinel node metastases (positive predictive value of 100%) as well as poor prognostic parameters. Patients with the opposite staining profile (pRb positive and p16 negative) were mostly without non-sentinel node metastases (negative predictive value of 75%). Cases negative for both pRb and p16 were consistently associated with a better prognostic phenotype and absence of additional axillary node metastases. In conclusion, the presence or absence of pRb in sentinel nodes is of little predictive value for non-sentinel node metastases unless taken in conjunction with the presence of p16 staining. Instead, it appears to enhance the positive predictive value of p16 in determining the presence of non-sentinel node metastases. Due to the limited subgroup sample size in this study, clinical guidelines cannot be suggested as yet, but further research focused on the pRb-negative/p16-positivie and pRb-negative/p16-negative phenotypes may yield beneficial results.     

Modes of benign mechanical transport of breast epithelial cells to axillary lymph nodes

The status of axillary lymph nodes is a key prognostic indicator available for the management of patients with breast cancer. Sentinel lymph node (SLN) evaluation as a predictor of lymph node status has led to increased use of ancillary methods, principally immunohistochemistry, to increase the sensitivity of the SLN biopsy. So-called "occult" micrometastases detected by such methods have led to speculation that some may have reached the SLNs by benign mechanical transport (BMT) rather than a metastatic process. We review evidence suggesting two potential modes of BMT: lymphatic transport of epithelial cells displaced by biopsy of the primary breast tumor and by breast massage-assisted SLN localization. The biopsy techniques under most scrutiny include fine needle aspiration and large-gauge core biopsy. The evidence implicating breast massage prior to SLN biopsy as a mode of BMT has been supported by statistical analysis; however, no method of distinguishing massage-associated cells in SLNs from true occult micrometastases is available. The significance of small epithelial clusters in SLNs is currently unknown. Thus, deviation from current biopsy and SLN-localizing practices is unwarranted.     

Sentinel-Node-Biopsie beim Mammakarzinom

This overview examines how the introduction of sentinel lymph node biopsy (SLNB) has changed the pathological staging of breast cancer. The more intensive analysis of the sentinel lymph nodes (gross slicing, step sections, immunohistological or molecular analysis) has lead to stage shifting in breast cancer. Regarding the rate of up-staging by positive results of SLNB, there are significant differences between institutes, some method-related, some related to the interpretation of results. Methodological differences should be reduced by means of reliable guidelines with the goal of systematically identifying metastases of a particular size (a macrometastasis over 2 mm being the minimum criterion). The next review of the TNM classification should result in a reduction in interobserver variability as a result of better definitions of staging categories for isolated tumor cells and micrometastases. In addition, a staging category is expected for metastases which have been identified by calibrated quantitative molecular tests only and which are larger than isolated tumors. Even in settings where nodal staging by SLNB is based on molecular tests at least a proportion of the lymph node should be investigated histologically.     

Keratin immunohistochemistry does not contribute to correct lymph node staging in patients with invasive lobular carcinoma

Studies suggest that immunohistochemistry improves rate of detecting sentinel lymph node metastases and is needed for adequate staging in invasive lobular carcinoma. Our study evaluates the use of cytokeratin immunohistochemistry in detecting sentinel lymph node metastases and its effect on staging patients with invasive lobular carcinoma. Material from 76 patients with invasive lobular carcinoma was reviewed. Cytokeratin immunostaining was performed on negative nodes, and deposits were classified as macrometastasis (>2.0 mm), micrometastasis (>0.2-2 mm), or isolated tumor cells (相似文献   

Intraoperative cytologic evaluation of sentinel lymph nodes in patients with breast carcinoma by scrape preparation

Intraoperative evaluation of sentinel lymph nodes (SLNs) in patients with breast carcinoma allows surgeons to complete axillary lymph node dissection in one procedure if any SLN shows metastasis. The accuracy of intraoperative pathological diagnosis is critical for decision-making. The purpose of this study was to evaluate our rapid intraoperative cytologic diagnosis of SLN through comparing with the final surgical pathologic diagnosis of the corresponding lymph nodes. A total of 454 SLNs from 159 consecutive female patients with a preoperative diagnosis of breast carcinoma over 3-year period were included in this study. After gross examination of each bisected lymph node, a scrape preparation was prepared for each submitted lymph node and was stained by the rapid Papanicolaou method. The intraoperative cytologic diagnosis was compared with the final surgical pathologic diagnoses. The overall sensitivity of intraoperative cytology was 52.5% with specificity of 100%. There were 17 false-negative cases. Of them, six nodes had isolated tumor cells, seven nodes had micrometastasis (0.2-2 mm), and four nodes had macrometastasis (>2 mm). There were no interpretive errors identified. The size of metastasis and tumor grade appeared to be significant factors in detecting metastasis by cytology. In addition, subsequent non-SLN involvement was 9% in patients with micrometastasis versus 50% in patients with macrometastasis (P < 0.05). Our study shows that the intraoperative cytologic evaluation of SLNs in breast carcinoma is a reasonably accurate method. The majority of false-negative cases were due to micrometastasis and isolated tumor cells.     

The role of sentinel lymph node biopsy in the management of breast cancer

Axillary nodes status is the best single predictor of disease outcome in patients with breast cancer; presence ofaxillary node metastasis (ANM) reduces the patient's 5-year survival by 28-40%. However, ANM is seen in only 40% of all breast cancer and furthermore since axillary lymph node dissection (ALND) is associated with significant morbidity, sentinel lymph node biopsy (SLNB) seems to be a good alternative for nodal staging in breast cancer. Pathologically negative sentinel lymph node (SLN) is able to predict the absence of metastasis to the remainder of the regional lymph node basin with a very high degree of certainty. This article presents a systematic detailed review of the existing studies on SLNB in relation to the following parameters: sensitivity and accuracy of the different techniques used; pathologic evaluation of SLN; clinical and pathological factors affecting SLN status and role of SLNB in different clinical situations related to breast cancer management. We have also included brief mention of our experience at UMass from a pathological perspective in this review article.