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.     

Evaluation of axillary sentinel lymph node biopsy by immunohistochemistry and multilevel sectioning in patients with breast carcinoma

BACKGROUND: Axillary lymph node dissection for evaluation of the presence or absence of metastatic disease is the single most important prognostic factor for patients with newly diagnosed primary breast cancer. Recently, sentinel lymph node (SLN) biopsy is being investigated as an alternative to the evaluation of the entire axilla. We evaluated whether the application of multilevel sectioning and immunohistochemistry in SLNs will increase the accuracy of detection of metastatic deposits. METHODS: Between October 1998 and July 1999, 38 patients with breast carcinoma (25 ductal, 5 lobular, 4 tubular, and 4 mixed ductal and lobular) underwent successful SLN biopsy followed by complete axillary node dissection. Sentinel lymph nodes were localized with a combination of isosulfan blue dye and radionuclide colloid injection. Frozen sections and permanent sections of SLNs were examined. All negative SLNs were examined for micrometastases by 3 additional hematoxylin-eosin (H&E)-stained sections and immunohistochemistry with the cytokeratins AE1/AE3. RESULTS: Sentinel lymph nodes were successfully identified surgically in 38 (93%) of 41 patients. There was a 97% correlation between the results of the frozen sections and the permanent H&E-stained sections. Twelve (32%) of 38 patients showed evidence of metastatic disease in their SLN by routine H&E staining. In 7 (58%) of 12 patients with positive nodes, the sentinel node was the only positive node. The 26 patients with negative SLN examination by H&E were further analyzed for micrometastases; 5 (19%) were found to have metastatic deposits by immunohistochemistry. Of these patients, 2 were also converted to node positive by detection of micrometastatic disease by examination of the additional H&E levels. CONCLUSIONS: Sentinel lymph nodes can be accurately identified in the axilla of breast cancer patients. Evaluation of SLNs provides reliable information representative of the status of the axilla in these patients. Immunohistochemistry and, to a lesser degree, detailed multilevel sectioning are able to further improve our ability to detect micrometastatic disease in SLNs of breast cancer patients.     

Multiparameter flow cytometry as a tool for the detection of micrometastatic tumour cells in the sentinel lymph node procedure of patients with breast cancer

AIM: To investigate whether multiparameter flow cytometry (MP-FCM) can be used for the detection of micrometastasis in sentinel lymph nodes (SLNs) in breast cancer. METHODS: Formalin fixed, paraffin wax embedded sentinel lymph nodes (n = 238) from 98 patients were analysed. For each lymph node, sections for haematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) for cytokeratin (MNF116) were cut at three levels with a distance of 500 microm. The intervening material was used for MP-FCM. Cells were immunostained with MNF116, followed by an incubation with fluorescein isothiocyanate (FITC) labelled goat antimouse immunoglobulin. DNA was stained using propidium iodide. From each lymph node 100,000 cells were analysed on the flow cytometer. RESULTS: Thirty eight of the 98 patients with breast carcinoma showed evidence of metastatic disease in the SLN by one ore more of the three methods. In 37 of 38 cases where metastatic cells were seen in the routine H&E and/or IHC, more than 1% cytokeratin positive cells were detected by MP-FCM. In 24 patients, metastatic foci were more than 2 mm (macrometastasis) and in 14 these foci were smaller than 2 mm (micrometastasis). In three of these 14 cases, MP-FCM revealed positive SLNs, although this was not seen at first glance in the H&E or IHC sections. After revision of the slides, one of these three remained negative. However, MP-FCM analysis of the cytokeratin positive cells showed an aneuploid DNA peak, which was almost identical to that of the primary breast tumour. Duplicate measurements, done in 41 cases, showed a 99% reproducibility. In five of 14 patients with micrometastasis, one or two metastatic foci were found in the non-SLN. However, in 15 of 24 macrometastases multiple non-SLNs were found to have metastatic tumour. All micrometastases except for the remaining negative one mentioned above showed only diploid tumour cells, despite the fact that their primary tumours contained both diploid and aneuploid tumour cells. In primary tumours with more than 60% aneuploid cells, predominantly aneuploid macrometastasis were found, whereas diploid primary tumours only showed diploid micrometastases or macrometastases in their SLN. Aneuploid SLN macrometastases were associated with non-SLN metastases in five of seven patients, whereas diploid cases showed additional non-SLN metastases in only seven of 16 patients. CONCLUSION: In all cases, MP-FCM was sufficient to detect micrometastatic tumour cells in a large volume of lymph node tissue from SLNs. In some cases it was superior to H&E and IHC staining. Approximately 30% of SLN micrometastases are accompanied by additional non-SLN metastases. The size of the aneuploid fraction (> 60%) in the primary tumour may influence the risk of having both SLN and non-SLN metastases.     

Can Melan-A replace S-100 and HMB-45 in the evaluation of sentinel lymph nodes from patients with malignant melanoma?

The sentinel lymph node (SLN) biopsy has become an increasingly important procedure used in the primary staging of malignant melanoma. However, micrometastases in a lymph node can be easily missed on routine H&E-stained sections. Therefore, S-100 and HMB-45 IHC stains are standardly performed on grossly negative SLNs for detection of metastatic melanoma. Each of these IHC markers, however, is not ideal. The authors investigated whether the newer IHC marker Melan-A would improve the detection of metastatic melanoma in SLN biopsies. Forty lymph nodes previously diagnosed with metastatic melanoma were retrospectively evaluated for S-100, HMB-45, and Melan-A expression. In addition, 42 SLN biopsies for metastatic melanoma detection were prospectively collected and evaluated for S-100, HMB-45, and Melan-A expression. All lymph nodes with metastatic melanoma from the retrospective study demonstrated S-100 reactivity. Five of the lymph nodes with metastatic melanoma from the retrospective study failed to express either HMB-45 or Melan-A, all of which displayed a desmoplastic morphology. One of the metastases positive for S-100 and HMB-45 failed to show reactivity with Melan-A (3%). The prospective study found 10 lymph nodes from 42 cases to be positive for metastatic melanoma, which were positive for S-100 (100%). Nine of the involved lymph nodes were positive for HMB-45(90%), and nine were positive for Melan-A (90%). Melan-A, although very specific, cannot replace the use of S-100 and HMB-45 for the detection of metastatic melanoma in SLNs. It can, however, substitute for HMB-45 with equally good results.     

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.     

Strategies for optimizing pathologic staging of sentinel lymph nodes in breast cancer patients

Due to the extensive pathologic evaluation of the sentinel lymph node (SLN), micrometastases are frequently observed. If micrometastases are clinically relevant, the histopathologic examination of SLNs should be sensitive enough to detect them. The probability of detecting micrometastases was calculated when examining the SLN according to the current Dutch pathology protocol and strategies evaluated to optimize the chance of detection. The dimensions of 20 consecutive axillary SLNs in patients with cT1-2N0 breast cancer were measured. In a mathematical model, the probability of detecting micrometastases in a SLN was calculated. Similarly, strategies to optimize the probability of detecting micrometastases were explored. When applying the pathology guidelines, the calculated probability to detect a micrometastasis was 18% for a 200-microm micrometastasis and 69% for a 2.0-mm metastasis in a median sized SLN. To detect the smallest micrometastasis in a median-sized SLN with a 95% probability, the interval between the sections must be decreased to 200 microm, and 20 levels from both halves must be examined. Given a prognostic significance of micrometastases, our current pathology guidelines are not sensitive enough. The number of sections should be increased, while the interval between cuts should be no more than 200 microm.     

Intraoperative sentinel lymph node evaluation in patients with node-positive breast cancer status post neoadjuvant systemic therapy - An institutional experience

Recent studies have shown the feasibility and utility of sentinel lymph node (SLN) biopsy in patients with biopsy proven node-positive breast cancer after neoadjuvant chemotherapy. We reviewed our experience in intraoperative SLN evaluation in such cases and its effect on axillary management. A retrospective analysis of breast cancer patients (2015–2018) with a biopsy-proven positive axillary lymph node, who received neoadjuvant systemic therapy and underwent intraoperative SLN assessment was performed. Intraoperative SLN assessment results were compared with final pathology. Its accuracy and effect on axillary management is summarized. We identified 106 patients with positive axillary lymph node and neoadjuvant systemic therapy between the ages of 28 and 75 years who had SLN biopsy and lumpectomy (33) or mastectomy (73). Three or more SLNs were identified in 91 cases (86 %). The previously biopsied lymph node was identified as one of the sentinel lymph nodes in 93 cases (88 %). There is a high concordance rate between frozen section diagnosis and final diagnosis on sentinel lymph nodes. No false positive case and seven false negative frozen section diagnosis cases (diagnosed as negative on frozen section and positive on permanent sections) were identified. False-negative frozen section diagnosis correlated with low-volume nodal disease and obscuring tumor bed changes. Almost half of the positive lymph nodes were converted to negative after neoadjuvant chemotherapy. SLN biopsy with intraoperative frozen section evaluation after neoadjuvant systemic therapy in node-positive patients is an effective way to minimize axillary surgery.     

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 lymph node investigation in melanoma: detailed analysis of the yield from step sectioning and immunohistochemistry

AIMS: To evaluate in detail the extent to which step sectioning and immunohistochemical examination of sentinel lymph nodes (SLNs) in patients with melanoma reveal additional node positive patients, to arrive at a sensitive yet workable protocol for histopathological SLN examination. METHODS: The study comprised 29 patients with one or more positive SLN after a successful SLN procedure for clinical stage I/II melanoma. SLNs were lamellated into pieces of approximately 0.5 cm in size. One initial haematoxylin and eosin (H&E) stained central cross section was made for each block. When negative, four step ribbons were cut at intervals of 250 microm. One section from each ribbon was stained with H&E, and one was used for immunohistochemistry (IHC). RESULTS: When taking the cumulative total of detected metastases at level 5 as 100%, the percentage of SLN positive patients increased from 79%, 83%, 83%, 90% to 93% in the H&E sections through levels 1-5, and with IHC these values were 83%, 86%, 90%, 97%, and 100%, respectively. One of six patients in whom metastases were detected at levels 2-5 only had metastases in the subsequent additional lymph node dissection. CONCLUSIONS: Multiple level sectioning of SLNs (five levels at 250 microm intervals) and the use of IHC detects additional metastases up to the last level in melanoma SLNs. Although more levels of sectioning might increase the yield even further, this protocol ensures a reasonable workload for the pathologist with an acceptable sensitivity when compared with the published literature.     

Intraoperative examination of the sentinel lymph node for breast carcinoma staging.

Intraoperative pathologic examination of the sentinel lymph node (SLN) draining a primary breast carcinoma allows an SLN-positive patient to undergo complete axillary lymphadenectomy as part of the same surgical procedure. However, the optimal technique for rapid SLN assessment has not been determined. We reviewed our results with imprint cytology (IC) and frozen section (FS) examination of SLNs from 278 patients. Compared with H&E-stained paraffin sections, IC and FS had an overall accuracy of 93.2%. The false-reassurance rate (false-negative results/all negative results) was 8.4%. It correctly identified 98% of macrometastases but only 28% of micrometastases. There were no false-positive results. Compared with paraffin-section cytokeratin immunohistochemistry results, the IC-FS false-reassurance rate increased to 25.8%. The false-reassurance rate decreased with smaller primary tumor size (T1 vs T2/3) and ductal type, smaller diameter of the SLN (< or = 2.0 cm), and greater pathologist experience. IC combined with 2-level FS reliably identifies SLN macrometastases but commonly fails to detect SLN micrometastases. If SLN micrometastasis is used to determine the need for further lymphadenectomy, more sensitive intraoperative methods will be needed to avoid a second operation.     

Lymphangiogenesis in breast cancer is associated with non-sentinel lymph node metastases in sentinel node positive patients

Axillary lymph node dissection (ALND) is not suggested in breast cancer patients with negative sentinel lymph node (SLN) biopsies, and SLN is the only positive node in 40-70% of the remaining cases. To distinguish a subgroup in which ALND would be omitted, we investigated the role of lymphangiogenesis in primary breast cancer as a risk factor for distal lymph node involvements in patients with positive SLNs. 86 patients were included in this study. The frequency of proliferative lymphatic endothelial cells (LECP%) was evaluated in each specimen after immunohistochemical double staining for D2-40 and Ki-67. Larger primary tumor size, increased number of positive SLNs, lymphatic vessel invasion and LECP% were significantly associated with non-SLN metastases in the univariate analysis, but only LECP% retained significance in the multivariate model. A positive correlation between LECP% and lymphatic vessel invasion was also revealed. Our study confirmed the important role of lymphangiogenesis in tumor spread, and suggested that LECP% is a promising predictor for additional axillary lymph node involvements.     

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.     

The development of optimal pathological assessment of sentinel lymph nodes for melanoma

1158 sentinel lymph nodes (SLNs), excised from patients with primary cutaneous melanoma, were assessed pathologically using histology with immunohistochemistry (IHC) on all nodes, and RT-PCR for Mart-1 and tyrosinase on 55 nodes. RT-PCR was compared with the histology and IHC assessed on the same nodes. The evaluation of progressively more detailed protocols for histology and IHC modulated by the RT-PCR results led to a procedure that consistently detects metastases in 34% of patients submitted to SLN biopsy for cutaneous melanomas with a vertical growth phase and a mean thickness of 2.02 mm (range 0.25, with regression, to 19 mm). As this technique is virtually free of false positives and produces only a marginally lower detection rate than RT-PCR, which was subject to false positives of 7% in our study, it is suggested that this extended protocol should be the basis on which further evaluation of the place of RT-PCR in SLN assessment takes place. The evolved protocol described here has been adopted by the EORTC as the standard procedure for pathological handling of sentinel lymph nodes for melanoma when SLN status is a criterion in their clinical trials or studies.     

Iatrogenically false positive sentinel lymph nodes in breast cancer: Methods of recognition and evaluation

With the introduction of sentinel lymph node (SLN) biopsy as a standard procedure for staging clinically node negative breast cancer patients, meticulous pathologic evaluation of SLNs by serial sections and/or immunohistochemistry for cytokeratins has become commonplace in order to detect small volume metastases (isolated tumor cells and micrometastases). This practice has also brought to the fore the concept of iatrogenically false positive sentinel nodes secondary to epithelial displacement produced largely by preoperative needling procedures. While this concept is well described in the clinical and pathologic literature, it is, in our experience, still under-recognized, with such lymph nodes frequently incorrectly diagnosed as harboring true metastases, possibly resulting in unwarranted further surgery and/or chemotherapy. This review discusses the concept of displaced epithelium in the histologic evaluation of breast surgical specimens and provides a stepwise approach to the correct identification of iatrogenically transported displaced epithelial cells in sentinel lymph nodes.     

本院5年来乳腺癌前哨啉巴结活检报告

目的探讨乳腺癌前哨淋巴结活检技术的可行性和前哨淋巴结的组织学状况能否准确预告腋淋巴结的状况。方法使用美蓝染色和或^99mTc-SC同位素示踪法对我院收治的108例乳腺癌患者进行前哨淋巴结活检。结果108例患者中有95例成功确定前哨淋巴结，检出率88％，其中关蓝组为87S（S5／98），美蓝与核素联合组全部检出（100S）。40岁以下的妇女检出率明显高于40岁以上的妇女（P〈0．05），而假阴性率有显著性增高。97例浸润性癌（包括导管癌和腺癌）中假阴性率为22％，但当使用免疫组化检查法以后，假阴性率下降至14％。结论前哨淋巴结活检技术在临床是可行的，绝大多数前哨淋巴结可以比较准确地反映其余腋窝淋巴结的组织学特点。美蓝染色和／或^99mTc-SC同位素示踪法结合应用是较好的选择方法。     

Analysis of sentinel node biopsy - a single-institution experience supporting the use of serial sectioning and immunohistochemistry for detection of micrometastases by comparing four different histopathological laboratory protocols

Grabau D, Ryden L, Fernö M & Ingvar C
(2011) Histopathology 59 , 129–138 Analysis of sentinel node biopsy – a single‐institution experience supporting the use of serial sectioning and immunohistochemistry for detection of micrometastases by comparing four different histopathological laboratory protocols Aims: Detecting micrometastases (>0.2 and ≤2 mm/>200 cells) and isolated tumour cells (ITCs; ≤0.2 mm/<200 cells) is important for staging of breast cancer patients. The aim of this study was to systematically compare several laboratory protocols used to detect metastases after initial intraoperative frozen section examination. Methods and results: Four different protocols for the work‐up of sentinel lymph nodes (SLNs) after frozen sectioning were applied in the routine diagnostic process from 2001 to 2009. In addition, team‐work with a limited number of laboratory technicians and pathologists handling SLNs was introduced in 2008. The present study shows that there were, overall, significantly more node‐positive patients in the period when team‐work and intensive step sections including immunohistochemistry (IHC) were used (P = 0.01). This resulted in 13% more patients being found to have ITCs and micrometastases than in a time period when only step sections were performed. No increase in the number of false‐negative frozen sections was seen. Conclusions: Future guidelines for pathological work‐up of sentinel nodes in women with breast cancer might include team‐work and IHC if frozen sections are used intraoperatively.     

Axillary staging of breast cancer and the sentinel node

Pathological aspects of axillary nodal staging of breast cancer and in particular sentinel lymph node (SLN) biopsy are reviewed. SLN biopsy seems an almost ideal staging procedure because it has both high accuracy and a low false negative rate. It may also allow a cost effective use of more sensitive methods of metastasis detection. However, the biological relevance of metastases detected only by modern tools remains to be elucidated. This review focuses on standard axillary staging and the histopathological investigation of SLNs, with emphasis on the intraoperative setting. Future trends including ancillary studies, quality control issues, prediction of non-SLN involvement, and suggestions concerning the minimum requirements for the histology of axillary SLNs are also discussed.     

Sentinel lymph nodes for breast carcinoma: an update on current practice

Sentinel lymph node (SLN) biopsy has been established as the standard of care for axillary staging in patients with invasive breast carcinoma and clinically negative lymph nodes (cN0). Historically, all patients with a positive SLN underwent axillary lymph node dissection (ALND). The ACOSOG Z0011 trial showed that women with T1–T2 disease and cN0 who undergo breast‐conserving surgery and whole‐breast radiotherapy can safely avoid ALND. The main goal of SLN examination should be to detect all macrometastases (>2 mm). Gross sectioning of SLNs at 2‐mm intervals and microscopic examination of one haematoxylin and eosin‐stained section from each SLN block is the preferred method for pathological evaluation of SLNs. The role and timing of SLN biopsy for patients who have received neoadjuvant chemotherapy is controversial, and continues to be explored in clinical trials. SLN biopsies from patients with invasive breast carcinoma who have received neoadjuvant chemotherapy pose particular challenges for pathologists.     

乳腺癌非前哨淋巴结转移的预测

目的 :预测非前哨淋巴结 (non SLN)转移 ,以筛选出转移局限于前哨淋巴结 (SLN)的乳腺癌患者。方法 :采用99mTc SC作为示踪剂 ,对 95例乳腺癌患者行前哨淋巴结活检 ,对乳腺癌非前哨淋巴结转移进行单因素和多因素分析。结果 :95例患者中成功发现 91例患者有SLN (95 8% ) ,其中 85例患者SLN能准确反映腋窝淋巴结的病理状况 (93 4% )。临床肿块大小(P =0 0 2 8)、肿瘤分级 (P =0 0 40 )和原发灶cyclinD1蛋白 (P =0 0 17)的表达与non SLN转移显著相关。而Logistic多因素分析证实 ,临床肿块大小、肿瘤分级为独立的预测非前哨淋巴结转移的因子。结论 :可根据临床病理学特征 ,筛选出乳腺癌转移只局限于前哨淋巴结的患者 ,也存在免除腋窝淋巴结清扫的可能性     

乳腺癌前哨淋巴结微转移分子检测及其临床意义

目的探讨乳腺癌前哨淋巴结(SLN)定位和SLN微转移检测的临床意义。方法对66例乳腺癌患者行术前Y探测仪SLN定位,用RTPCR法检测SLN中CK19mRNA的表达。同时与常规病检法比较其检测敏感性。并比较转移组、微转移组、无转移组患者的临床病理资料。结果SLN定位成功率为97%,RTPCR法与常规病检法转移的检出率相比较差异有统计学意义(P<0.05)。在常规病检阴性的38例淋巴结中,RTPCR法检出8例有微转移。同时乳腺癌转移组与微转移组患者在肿物大小与淋巴管浸润上有相似性,而同无转移组差异有统计学意义(P<0.05)。结论RTPCR法较常规病理检查更为敏感,通过SLN定位和RTPCR的联合使用,可明显提高乳腺癌SLN微转移的检出率。同时也证明RTPCR法是可靠的,SLN微转移有可能作为肿瘤预后的指标。