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.     

Rapid intraoperative immunohistochemical evaluation of sentinel lymph nodes for metastatic breast carcinoma.

OBJECTIVE: Sentinel lymph node (SLN) biopsy is an integral part of the surgical management of patients with breast cancer. Rapid immunohistochemistry (RIHC) has the potential to increase detection of metastatic carcinoma at the time of frozen section consultation. The authors assessed the accuracy and turnaround time of a newly developed RIHC method for pancytokeratin (RIHC-CK). METHODS: Sixty-six SLNs from 32 patients with breast carcinoma were examined for metastasis using the Zymed Sentinel Lymph Node Rapid IHC Kit. Intraoperative frozen sections (6 mum) of the SLNs were incubated with Zymed anti-pan-cytokeratin/HRP conjugate, diaminobenzidine (DAB), and stained with hematoxylin. Slides were ready within 8 minutes and were interpreted as positive or negative for metastatic carcinoma. Results were compared with previous intraoperative touch preparations, frozen sections, hematoxylin and eosin (Perm H&E), and AEl/3-immunostained permanent sections (Perm CK). RESULTS: Fourteen lymph nodes (19%) in 13 patients tested positive for metastatic carcinoma in Perm H&E, the gold standard. RIHC-CK had the highest sensitivity (92%) of the intraoperative tests, compared with touch preparations (64%) and frozen sections (80%). RIHC-CK showed 94% accuracy, compared with 96% (frozen section) and 93% (touch preparation). The RIHC technique took 8 minutes and was easy to perform and interpret. CONCLUSIONS: Zymed RIHC is a sensitive method for detecting breast cancer metastases in SLNs. The speed, accuracy, and ease of interpretation of the test allow for recognition of micrometastases (<2 mm) that might otherwise be undetectable by current methods of intraoperative evaluation. The prognostic significance and effect on surgical management of micrometastases in SLNs have yet to be determined.     

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.     

Accuracy of frozen section diagnosis: a retrospective analysis of 4785 cases

During a 1-year period 4785 intraoperative consultations were performed. The pathology reports were retrospectively reviewed to determine the accuracy of frozen section diagnosis in various tissue types. Skin for evaluation of section margins and axillary sentinel lymph nodes for evaluation of metastatic disease were most frequently sent for frozen section diagnosis. The number of discordant cases were 182, 178 were false negative and four were false positive. When frozen section diagnoses were compared with permanent section diagnoses, the overall diagnostic concordance was 95.1%. The number of deferred specimens was 57. The accuracy of frozen section diagnosis varied between tissue types, and axillary sentinel lymph nodes accounted for the greatest number of discordances. In conclusion, the frozen section diagnosis is a reliable method with varying concordance and deferral rates between tissue types. We suggest regular monitoring of the performance in frozen section diagnosis.     

Reliability of intraoperative frozen section and imprint cytological investigation of sentinel lymph nodes in breast cancer

AIMS: The sentinel lymph node procedure enables selective targeting of the first draining lymph node, where the initial metastases will form. A negative sentinel node (SN) predicts the absence of tumour metastases in the other regional lymph nodes with high accuracy. This means that in the case of a negative SN, regional lymph node dissection is no longer necessary. Besides saving costs, this will prevent many side-effects of lymph node dissection. The aim of this study was to evaluate the reliability of intraoperative cytological and frozen section investigation of the SN to detect metastases. This would allow the axillary lymph node dissection to be performed in the same session as the SN procedure and the excision of the primary tumour in case of a positive SN. METHODS AND RESULTS: Seventy-four SNs were detected by gamma probe detection of nanocolloid and visual localization of Patent Blue accumulations in 54 women with stage T1-2N0M0 invasive breast cancer. The identified SN were immediately investigated by frozen section and imprint cytological investigation. Diagnoses were confirmed on the paraffin material, and in case of negative frozen section and paraffin haematoxylin and eosin sections, skip sections and immunohistochemistry were performed. Thirty-one SNs (42%) contained metastases, of which 27 were detected by the frozen section procedure (sensitivity 87%). There were no false positives (specificity 100%). The sensitivity of the imprints was 62% with a specificity of 100%. When evaluating the data per patient, for the frozen section procedure the sensitivity was 91% and the specificity 100%, and for the imprints, the sensitivity was 63% and the specificity 100%. There were no SNs in which the imprints showed metastases and the frozen section did not. CONCLUSIONS: Intraoperative frozen section analysis is a reliable procedure by which a high percentage of sentinel lymph node metastases can be detected in breast cancer patients without false positive results. This allows the surgeon to perform an immediate axillary lymph node dissection in case of positive SNs. In up to 10% of cases, the final paraffin sections will reveal micrometastases that were not detected by the frozen section, and in these patients axillary lymph node dissection will have to be performed in a second session. The imprint method is significantly less sensitive than the frozen section but may be used as an alternative when frozen section is not possible.     

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   

Intraoperative evaluation of sentinel lymph nodes in breast carcinoma by imprint cytology,frozen section and rapid immunohistochemistry

Sentinel lymph nodes (SLN) isolated in 40 patients of breast carcinoma (stage T₁/T₂) were evaluated intraoperatively by imprint cytology and frozen section. Rapid immunohistochemistry (IHC) was done in cases where both imprint smears and frozen sections were negative for any metastatic tumor deposits. The results of these different techniques were compared with postoperative paraffin sections taken as “Gold Standard.” Nottingham modification of Bloom Richardson scoring system was used for grading the tumors. Further, the correlation of the SLN status with tumor size, grade, and lymphovascular invasion was studied. The sensitivity, specificity, and overall accuracy of imprint cytology were 91.7, 100, and 95% respectively, and those of the frozen section were 95.8, 100, and 97.5% respectively. Examination of multiple serial sections improved the sensitivity and overall accuracy of frozen section. Results of intraoperative rapid IHC were equivalent to final paraffin sections. Histological grade and lymphovascular invasion were in direct correlation with SLN metastasis (P < 0.05). The risk of lymphovascular invasion increased from 22.2% in grade I tumors to 85.7% in grade III tumors. SLN biopsy is a reliable method to evaluate the status of the axillary lymph nodes. Imprint cytology can be used reliably where the facility of frozen section is not available. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Use of intraoperative stereomicroscopy for preventing loss of metastases during frozen sectioning of sentinel lymph nodes in breast cancer

Aims:  Optimal detection of metastases in sentinel lymph nodes (SLN) remains controversial. To determine the reliability of intraoperative frozen sections, SLN protocol with one frozen section was compared with macroscopic SLN evaluation with consecutive complete SLN embedding.
Methods and results:  SLN from 135 consecutive breast cancer patients were analysed under a sereomicroscope. Frozen sections were performed in suspicious or clearly involved SLN on cut surface. One control group ( n  = 143) underwent one intraoperative frozen section on each SLN. The second control group ( n  = 90) was subjected to stereomicroscopy and one intraoperative frozen section on each SLN. A conventional SLN protocol with cytokeratin immunohistochemistry was performed postoperatively in all cases. All groups were statistically comparable. In the study group metastases were suspected in 21 SLN (16%) under the stereomicroscope and all were confirmed histologically. The negative SLN rate was significantly lower in the study group than in the main control group (47% versus 64%, P  = 0.008), suggesting loss of metastases during frozen sections. More macrometastases were detected in the study group (30% versus 15%, P  = 0.006); there were no differences in isolated tumour cells or micrometastases. The false-negative rate was significantly lower in the control groups (29% versus 13% and 12%, P  = 0.001).
Conclusions:  Frozen sections potentially lead to loss or reduced size of metastatic deposits in SLN. Avoiding intraoperative frozen sections on grossly inconspicuous SLN may therefore be justified.     

Accuracy and cost of intraoperative lymph node frozen sections at radical prostatectomy

AIM: To assess the value of intraoperative diagnostic examination of frozen sections of lymph nodes removed during radical prostatectomy. METHODS: Pelvic lymph nodes from patients with prostatic carcinoma were obtained (1) as frozen sections during radical prostatectomy, to exclude patients from non-curative surgery, and (2) as paraffin sections postoperatively from lymphadenectomy performed at radical prostatectomy, to stage the tumour and assess need for adjuvant treatment. Findings from the two approaches were used to assess the accuracy and cost of frozen section diagnosis, and to judge the results of omitting intraoperative diagnosis. RESULTS: In 82 patients frozen section revealed metastasis in six (7.3%), and metastases were found in a further four (4.9%) on paraffin sections (false negatives). Of the 195 patients undergoing staging lymphadenectomy (without frozen section), metastatic cancer was seen in nine cases (4.6%). The frozen section cost of metastatic cancer detection per patient was calculated as 7516 Pounds (550 Pounds x 82/6), with an associated false negative rate of 33%. CONCLUSIONS: Frozen section diagnosis of metastatic carcinoma in pelvic lymph nodes before radical prostatectomy has a high false negative rate and is costly. It may not be justified with the observed low incidence of lymph node metastasis.     

Anatomopathological analysis of sentinel and nonsentinel lymph nodes in breast cancer: hematoxylin-eosin versus immunohistochemistry

The authors compare the detection of metastases in sentinel lymph nodes (SLNs) and nonsentinel lymph nodes (NSLNs) using hematoxylin-eosin (HE) staining versus immunohistochemistry (IHC). Thirty-six patients with breast carcinoma undergo exeresis of the primary tumor and of 50 SLNs and 491 NSLNs. Sentinel lymph nodes are sectioned into transverse slices of 2- to 3-mm thickness, and a cytologic smear and a frozen section were obtained from each slice. The slices are completely cut into serial sections at 100-microm intervals. Two consecutive 4-microm-thick sections are then obtained from each level and were prepared for HE staining and IHC. Nonsentinel lymph nodes are evaluated similarly to SLNs. The authors obtain 4076 SLN sections and 32 012 NSLN sections, for a total of 36 088 sections. A comparison of HE staining versus IHC based on the total number of sections shows a sensitivity of 93.8%, a negative predictive value of 98.9%, and an accuracy of 99.1%. The values obtained by HE staining are similar to those obtained by IHC.     

Towards reasonable workload in diagnosis of sentinel lymph nodes: comparison of two frozen section methods

AIMS: To compare two methods of histological assessment with intraoperative diagnosis of sentinel node metastases in breast cancer. METHODS AND RESULTS: A total of 204 consecutive breast cancer cases with lymphatic mapping, sentinel node biopsy and intraoperative diagnosis were included. The sentinel nodes in the first 102 cases (method A) were bisected and serially sectioned. In the other 102 cases (method B) the nodes were sliced thinly with a razor blade. All 1-1.5 mm thick slices were mounted on prechilled mounting medium on frozen section buttons. Cytological imprints were also made of the attached tissue slices. Postoperative diagnosis of sentinel lymph node metatases was taken as gold standard. Sentinel node metastases were found in 28 (27%) cases in group A and in 42 (40%) cases in group B (P = 0.05). The median size of the sentinel node metastases was 4.3 mm in group A and 3.3 mm in group B (P < 0.05). CONCLUSION: Method B finds more and smaller metastases and takes less time and effort in the laboratory. When using method A, many small metastases are not detected at all.     

Frozen section diagnosis for axillary sentinel lymph nodes: the first six years.

Intraoperative frozen section of axillary lymph nodes for the detection of metastatic breast cancer has been controversial because of the labor-intensive techniques necessary to obtain a highly sensitive test, and because of the uncertain significance of frequently detected submicrometastatic carcinoma. In total, 874 consecutive axillary sentinel lymph node cases examined by intraoperative frozen section over a 6-year period were reviewed retrospectively. Frozen section had a sensitivity of 60% and was 100% specific, but when cases with submicrometastatic tumor cells were considered negative, the sensitivity rose to 83%. Rare cases were called 'atypical' on frozen section; almost all of these cases were negative for carcinoma on permanent sections.     

mRNA markers of breast cancer nodal metastases: comparison between mammaglobin and carcinoembryonic antigen in 248 patients

Histological detection of axillary lymph node metastases is still the most valuable prognostic parameter for breast cancer, but about 30% of node-negative patients relapse within five years, suggesting that current methods are inadequate for identifying metastatic disease. More sensitive, PCR-based methods for the detection of metastatic cells are now available, enabling the amplification of cancer cell-specific mRNA messages by the RT-PCR assay. An ideal tumour marker, consistently expressed in tumour samples and not at all in normal lymph nodes, remains to be identified. The present study first investigated the expression of seven mRNA markers, CEA, CK19, c-Met, mammaglobin, MUC-1, beta1-->GalNAc-T and p97, selected on the basis of their previously reported specificity for breast cancer cells. Eighteen lymph nodes were examined from patients without tumours. Only mammaglobin mRNA and CEA mRNA were not expressed in normal nodes. All of the other markers showed a band of expression in 17%-55% of cases, indicating that they are not breast cancer-specific. CEA mRNA and mammaglobin mRNA expression could be detected in 15/20 (75%) and 19/20 (95%) primary breast carcinomas, respectively. The expression of mammaglobin mRNA and CEA mRNA was then compared in axillary lymph nodes from 248 consecutive breast cancer patients, 89 with histologically documented lymph node metastasis and 159 without histological evidence of metastatic disease. Ninety-seven per cent of the patients with histologically involved nodes showed expression of mammaglobin mRNA, whereas CEA mRNA was expressed in 79% of these cases. In the group of patients with histologically negative lymph nodes, 46 (29%) and 32 (20%) were found to be positive for mammaglobin and CEA expression, respectively, indicating the presence of metastases not detected by routine histological examination of one lymph node section. These results show that both mammaglobin RT-PCR and CEA RT-PCR are useful tools for the detection of breast cancer metastases in axillary lymph nodes. The detection sensitivity of the mammaglobin RT-PCR is far superior to that of the CEA RT-PCR, allowing the diagnosis of occult metastases in nearly one-third of cases.     

Axillary sentinel lymph node examination in breast carcinoma.

OBJECTIVE: To evaluate whether the type of pathologic examination of breast sentinel nodes (frozen section, step sections, and immunoperoxidase staining) results in different percentages of nodes positive for metastatic disease. DESIGN: Twenty-eight consecutive patients with breast sentinel node biopsies were evaluated by step-sectioning the sentinel node(s) along with performing immunoperoxidase stains for low-molecular-weight cytokeratin and epithelial membrane antigen. SETTING AND PARTICIPANTS: The patients were from a university hospital and large private hospital. MAIN OUTCOME MEASURES: The results of the step sections and immunoperoxidase stains were compared with routine examination, that is, intraoperative frozen section along with a single hematoxylin-eosin slide. RESULTS: Nine cases were positive by routine evaluation, 10 by step sections, and 11 by immunoperoxidase staining. CONCLUSIONS: The large, multi-institutional studies of sentinel node utility must take into account the surgical pathology methods used to evaluate these specimens so that uniform techniques, which reliably predict the status of the axillary nodes, can be instituted at all institutions that use this procedure.     

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.     

Sentinel node investigation in breast cancer: 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 (SNs) in patients with breast cancer reveal additional node positive patients, to arrive at a sensitive yet workable protocol for histopathological SN examination. METHODS: This study comprised 86 women with one or more positive SN after a successful SN procedure for clinical stage T1-T2 invasive breast cancer. SNs 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 SN positive patients increased from 80%, 83%, 85%, 87% to 88% in the H&E sections through levels 1 to 5, and with IHC these values were 86%, 90%, 94%, 98%, and 100%. Three of nine patients in whom metastases were detected at levels 3-5 only had metastases in the subsequent axillary lymph node dissection. CONCLUSIONS: Multiple level sectioning of SNs (five levels at 250 microm intervals) and the use of IHC detects additional metastases up to the last level. 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.     

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.     

Predicting sentinel lymph node metastases in infiltrating breast carcinoma with vascular invasion

Sentinel lymph node and clinically negative axillary node status was compared with well-known clinicopathological characteristics such as tumor size, histologic and nuclear grade, lymphovascular invasion, steroid receptor, and HER-2 status in patients with breast cancer (pT1 and pT2). Positive sentinel lymph nodes were found in 29 of 100 patients: 19 with metastases detected by hematoxylin and eosin staining and 10 with micrometastases confirmed by immunohistochemistry with cytokeratin. Positive sentinel lymph nodes were present in larger carcinomas (P < 0.03), more frequently in tumors with negative PR status (P < 0.037) and evident lymphovascular invasion (P < 0.002). Lymphovascular invasion was also associated with breast cancer of higher histologic (P = 0.011) and nuclear grade (P = 0.039). Tumor size and the presence of lymphovascular invasion were found to be significant predictors of pathologically positive sentinel lymph node in T1 and T2.     

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.     

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.