Sections Of Sentinel Lymph Node Research Articles

Sentinel lymph node evaluation in endometrial cancer and the importance of micrometastases

The presence of lymph node (LN) metastases has a major impact on the prognosis of women with endometrial cancer and compromises recurrence-free time. LN assessment has become the standard of care in the surgical staging of patients and plays a crucial role in decision making. Sentinel lymph node (SLN) detection improves the accuracy of lymphatic drainage mapping compared to pelvic node dissection used alone. Serial sectioning of SLNs followed by immunohistochemical examination with conventional histology improves accuracy of micrometastatic identification. In this review, we found a high incidence of micrometastases in endometrial cancer, reaching 25% depending on the stage and the techniques used for the node examination. Current data are insufficient to evaluate the prognostic impact of the presence of micrometastases, but it seems that more accurate detection of lymphatic spread will allow better stratification of intermediate risk patients. Ultimately, this will assist in tailoring adjuvant treatment.

Serial sections of sentinel lymph nodes in breast cancer: How much do you need to cut?

Serial sections of sentinel lymph nodes in breast cancer: How much do you need to cut?

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

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. 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). 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.

Extensive Pathological Analysis of Selected Melanoma Sentinel Lymph Nodes: High Metastasis Detection Rates at Reduced Workload

Extensive pathological workup of sentinel lymph nodes (SLNs) in melanoma detects more patients with metastasis-positive SLNs than do routine protocols, but at the cost of high laboratory workloads. We aimed to design a protocol that reduced this workload without compromising metastasis detection. We analyzed 920 SLNs from 321 consecutive patients with melanoma by complete step sectioning and immunohistochemistry. We designed different models to theoretically reduce the number of histological sections examined and compared the results from these simulations with results obtained with our extended protocol, with the restricted national Danish protocol, and with the protocol recommended by the European Organization for Research and Treatment of Cancer (EORTC). The extended protocol increased the metastasis detection rate by 22% (95% confidence interval, 11-34; 30.8% vs. 25.2%, P < .0001) compared with the national Danish protocol, and it had a similar rate to that reported by the EORTC (30.8% vs. 29.4%, P = .6229). The workload associated with complete step sectioning could be reduced by 40% by focusing step sectioning on the SLNs with the highest gamma counts, while examining SLNs with lower gamma counts with one to three central sections. The false-negative rate for detecting metastases with this reduced protocol was 6% compared with complete step sectioning. Combining complete step sectioning of SLNs with immunohistochemistry ensures high metastasis detection rates. Workloads can be markedly reduced with only a slight increase in the false-negative rate by focusing analysis on the SLNs most likely to contain metastases, i.e., those with the highest gamma counts.

Intraoperative diagnosis of cancer metastasis in sentinel lymph node of oral cancer patients

Sentinel lymph node (SLN) biopsy in the head and neck region is attracting attention. If intraoperative frozen section and/or cytology of SLN is available, one can select an appropriate patient who must undergo neck dissection in a one-stage procedure. We began intraoperative diagnosis of SLN biopsy in patients who underwent oral cancer surgery in 2003. From August 2003 to December 2006, 44 previously untreated patients were accumulated. All patients underwent SLN biopsy prior to the resection of primary cancer. Intraoperative diagnosis of SLN biopsy was performed by multislice frozen section analysis. Patients with positive SLN underwent immediate neck dissection in the same session. Imprint cytology specimen was prepared at the same time. The results of frozen section analysis and imprint cytology were compared with postoperative pathologic diagnosis of permanent specimens. The sensitivity, specificity, overall accuracy, positive and negative predictive value of intraoperative multislice frozen section analysis in lymph node basis were 90.9%, 100%, 99.1%, 100% and 99.0%, respectively. On the other hand, the indexes of imprint cytology were 27.3%, 99.0%, 92.0%, 75.0% and 92.6%, respectively. All indexes of intraoperative frozen section analysis were superior to imprint cytology. In our experience, multislice frozen section analysis surpasses imprint cytology in intraoperative diagnosis of SLN biopsy.

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.

Prospective Randomized Study Comparing Sentinel Lymph Node Evaluation With Standard Pathologic Evaluation for the Staging of Colon Carcinoma

The principal role of sentinel lymph node (SLN) sampling and ultrastaging in colon cancer is enhanced staging accuracy. The utility of this technique for patients with colon cancer remains controversial. This multicenter randomized trial was conducted to determine if focused assessment of the SLN with step sectioning and immunohistochemistry (IHC) enhances the ability to stage the regional nodal basin over conventional histopathology in patients with resectable colon cancer. Between August 2002 and April 2006 we randomly assigned 161 patients with stage I-III colon cancer to standard histopathologic evaluation or SLN mapping (ex vivo, subserosal, peritumoral, 1% isosulfan blue dye) and ultrastaging with pan-cytokeratin IHC in conjunction with standard histopathology. SLN-positive disease was defined as individual tumor cells or cell aggregates identified by hematoxylin and eosin (H&E) and/or IHC. Primary end point was the rate of nodal upstaging. Significant nodal upstaging was identified with SLN ultrastaging (Control vs. SLN: 38.7% vs. 57.3%, P = 0.019). When SLNs with cell aggregates < or =0.2 mm in size were excluded, no statistically significant difference in node-positive rate was apparent between the control and SLN arms (38.7% vs. 39.0%, P = 0.97). However, a 10.7% (6/56) nodal upstaging was identified by evaluation of H&E stained step sections of SLNs among study arm patients who would have otherwise been staged node-negative (N0) by conventional pathologic assessment alone. SLN mapping, step sectioning, and immunohistochemistry (IHC) identifies small volume nodal disease and improves staging in patients with resectable colon cancer. A prospective trial is ongoing to determine the clinical significance of colon cancer micrometastasis in sentinel lymph nodes.

Combined application of RT-PCR and immunohistochemistry on paraffin embedded sentinel lymph nodes of prostate cancer patients

The detection of tumor cells in the sentinel lymph node (SLN) is of great importance for the prognosis of cancer patients. At present, immunohistochemistry and RT-PCR for tumor marker expression are the most sensitive techniques available for this analysis. However, so far, most RT-PCR-based analyses of SLNs have been performed on fresh material, excluding a direct comparison with the (immuno)histologic results. In our view, this does not entirely aid routine diagnosis. We established an efficient method for RNA extraction and RT-PCR from paraffin sections of SLNs from prostate cancer patients and compared the results with the (immuno)histologic data of adjacent sections. Amplifiable RNA was obtained from 133 SLNs of 68 prostate cancer patients. Correlation of PSA-specific RT-PCR with (immuno)histologic findings showed a positive and negative predictive value of 83% and 100%, respectively, for the prostate cancer patients investigated. Four of 12 patients with biochemical relapse, but without (immuno)histologically detectable tumor cells were RT-PCR-positive for PSA. We found that single sections of paraffin-embedded SLNs are suitable for routinely performed RT-PCR. Combined with (immuno)histology, PSA-specific RT-PCR is a revealing supplementary technique for the detection of tumor cells in SLNs of prostate cancer patients.

Clinical significance of PCR-detected metastases in sentinel nodes of breast cancer patients: An interim report

9516 Background: The presence of metastases in axillary lymph nodes (LN) is an important prognostic indicator in breast cancer and provides important staging information for treatment selection. Standard pathology fails to identify many patients with LN metastases; ∼30% “node-negative” patients die of recurrent disease. Retrospective analyses show that many of these LN contained missed metastases. In 1996 we initiated a prospective multicenter trial to test the hypothesis that RT-PCR analysis of sentinel lymph nodes (SLN) would improve the prediction of disease-free survival. Methods: In this translational study, we first identified mammaglobin (MAM) as a superior molecular marker, then proceeded to analyze blinded consecutive patient specimens. Alternate sections of SLN were analyzed by standard pathology (H&E, IHC) or frozen for end point RT-PCR for MAM. This is an interim report of the first cohort of 300 consecutive patients at 5 yrs follow-up. Results: MAM is expressed in 99% primary tumors (153/155)...

Clinical significance of PCR-detected metastases in sentinel nodes of breast cancer patients: An interim report

9516 Background: The presence of metastases in axillary lymph nodes (LN) is an important prognostic indicator in breast cancer and provides important staging information for treatment selection. Standard pathology fails to identify many patients with LN metastases; ∼30% “node-negative” patients die of recurrent disease. Retrospective analyses show that many of these LN contained missed metastases. In 1996 we initiated a prospective multicenter trial to test the hypothesis that RT-PCR analysis of sentinel lymph nodes (SLN) would improve the prediction of disease-free survival. Methods: In this translational study, we first identified mammaglobin (MAM) as a superior molecular marker, then proceeded to analyze blinded consecutive patient specimens. Alternate sections of SLN were analyzed by standard pathology (H&E, IHC) or frozen for end point RT-PCR for MAM. This is an interim report of the first cohort of 300 consecutive patients at 5 yrs follow-up. Results: MAM is expressed in 99% primary tumors (153/155) and in 93% (78/84) patients with path+ SLN. Patients with path–SLN (30%; 64/216) were upstaged based on high MAM expression. High MAM expression correlated with ER status, tumor size, and number of path+ LN (Χ2, p<0.02 each). MAM PCR detection of SLN metastases correlated with distant recurrence, with 5 yr survivals of 96% PCR–vs. 84% PCR+ (estimated by Kaplan-Meier; log rank p=0.02). Most importantly, MAM PCR detected nodal disease in the majority (5 of 9) of recurrent patients with path- LN. The addition of MAM PCR to histological LN staging improved correlation with distant metastases (p=0.02) independently of tumor size (p=0.01) by Cox regression. These are the first follow-up data to compare RT-PCR detection of LN metastasis with distant recurrence in breast cancer patients. Conclusions: MAM RT-PCR detection of metastatic disease is associated with a significant reduction in recurrence-free survival. This interim analysis indicates that PCR detection of metastatic disease appears to be a valuable prognostic indicator in breast cancer patients, complements staging by nodal pathology and may ultimately lead to more individualized therapy. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Veridex, LLC, a Johnson & Johnson Co. Veridex, LLC, a Johnson & Johnson Co. DOD Clinical Translational Research Award

Validation of markers for the intraoperative detection of metastasis in breast sentinel lymph nodes

9547 Background: The presence of axillary lymph node (ALN) metastasis is the most important prognostic factor for breast cancer patients. Sentinel lymph node (SLN) status is highly predictive of overall ALN involvement. SLN-positive patients have historically undergone ALN dissection in a second surgery. Intraoperative SLN analysis methods have been implemented to reduce the cost and complications of second surgeries, but these methods suffer from poor and variable sensitivity and a lack of standardization. We are investigating the feasibility of RT-PCR as the basis for improving the intraoperative diagnosis of clinically relevant SLN metastasis. Methods: Eight molecular markers, including mammaglobin, were identified from a genome-wide gene expression analysis of breast and other tissues. Alternate serial sections of SLN from 254 breast cancer patients were analyzed by permanent section H&E or quick frozen for RNA extraction. Blinded SLN cDNAs were analyzed by quantitative RT-PCR. PCR signal was compared to H&E results on a patient basis. Using multivariate receiver operating curves (ROCs), PCR cut-offs were selected that optimally correlated with H&E results. Results: A two-gene assay (mammaglobin and VBM1) detected clinically actionable metastasis (> 0.2 mm) with 90% sensitivity and 94% specificity. The performance of this marker combination was validated by leave half out cross-validation. Addition of a third gene had minimal impact on overall performance. Conclusions: This is the first comprehensive study demonstrating the utility of RT-PCR as the basis of an intraoperative assay for detecting clinically actionable breast metastasis. Mammaglobin / VBM1 expression closely correlates with standard H&E detection of SLN metastasis, demonstrating that molecular analysis has the potential to significantly reduce second surgeries for patients undergoing SLN biopsies. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Veridex, LLC, a Johnson & Johnson Co. Veridex, LLC, a Johnson & Johnson Co. Veridex, LLC, a Johnson & Johnson Co. Veridex, LLC

Validation of markers for the intraoperative detection of metastasis in breast sentinel lymph nodes

9547 Background: The presence of axillary lymph node (ALN) metastasis is the most important prognostic factor for breast cancer patients. Sentinel lymph node (SLN) status is highly predictive of overall ALN involvement. SLN-positive patients have historically undergone ALN dissection in a second surgery. Intraoperative SLN analysis methods have been implemented to reduce the cost and complications of second surgeries, but these methods suffer from poor and variable sensitivity and a lack of standardization. We are investigating the feasibility of RT-PCR as the basis for improving the intraoperative diagnosis of clinically relevant SLN metastasis. Methods: Eight molecular markers, including mammaglobin, were identified from a genome-wide gene expression analysis of breast and other tissues. Alternate serial sections of SLN from 254 breast cancer patients were analyzed by permanent section H&E or quick frozen for RNA extraction. Blinded SLN cDNAs were analyzed by quantitative RT-PCR. PCR signal was compared to H&E results on a patient basis. Using multivariate receiver operating curves (ROCs), PCR cut-offs were selected that optimally correlated with H&E results. Results: A two-gene assay (mammaglobin and VBM1) detected clinically actionable metastasis (> 0.2 mm) with 90% sensitivity and 94% specificity. The performance of this marker combination was validated by leave half out cross-validation. Addition of a third gene had minimal impact on overall performance. Conclusions: This is the first comprehensive study demonstrating the utility of RT-PCR as the basis of an intraoperative assay for detecting clinically actionable breast metastasis. Mammaglobin / VBM1 expression closely correlates with standard H&E detection of SLN metastasis, demonstrating that molecular analysis has the potential to significantly reduce second surgeries for patients undergoing SLN biopsies. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Veridex, LLC, a Johnson & Johnson Co. Veridex, LLC, a Johnson & Johnson Co. Veridex, LLC, a Johnson & Johnson Co. Veridex, LLC

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...

Evaluation of intraoperative frozen section diagnosis of sentinel lymph nodes in breast cancer.

Intraoperative frozen sections (FS) of sentinel lymph nodes (SLNs) can be used to detect metastatic disease, allowing immediate axillary lymph node dissection (ALND). However, pathological inconsistency in the SLNs diagnosis is sometimes encountered when the results of FS and permanent sections are compared. The purpose of this study was to reveal the usefulness and limitations of FS for the diagnosis of SLNs in patients with breast cancer. We reviewed the results for 569 patients with breast cancer at stage 0-II who underwent a sentinel node biopsy between February 1998 and December 2002. SLNs were analyzed using standard FS procedures and a single section stained with hematoxylin and eosin was examined. Patients determined to have positive SLNs based on the results of the FS diagnosis immediately underwent ALND. Permanent sections were later prepared from the remaining frozen tissues and examined using hematoxylin and eosin staining without additional immunohistochemical staining. Seven cases (1%) with atypical cells were found in the FS diagnosis intraoperatively, which were counted as "negative" by the following analysis. The final pathology results showed metastasis in the SLN sections in 159 patients (28%), of whom 26 were diagnosed as negative by the FS diagnosis. Accuracy, specificity and the false-negative rate were 95, 100 and 16%, respectively. The mean size of the nodal metastases in the false-negative cases was significantly smaller than that in the true-positive cases (n = 72) (P < 0.01). False-negative rates for T1b, T1c and T2 were 33, 19 and 14%, respectively. The rate of micrometastasis in T1 (43%) was significantly higher than that of T2 (13%) (P < 0.01). FS diagnosis for SLNs is reliable. Patients with negative SLNs by the FS diagnosis can avoid reoperation for ALND. However, FS may fail to detect micrometastases, especially in cases with small tumors.

Comparison of Pathologist-Detected and Automated Computer-Assisted Image Analysis Detected Sentinel Lymph Node Micrometastases in Breast Cancer

Sentinel lymph node biopsy has stimulated interest in identification of micrometastatic disease in lymph nodes, but identifying small clusters of tumor cells or single tumor cells in lymph nodes can be tedious and inaccurate. The optimal method of detecting micrometastases in sentinel nodes has not been established. Detection is dependent on node sectioning strategy and the ability to locate and confirm tumor cells on histologic sections. Immunohistochemical techniques have greatly enhanced detection in histologic sections; however, comparison of detection methodology has not been undertaken. Automated computer-assisted detection of candidate tumor cells may have the potential to significantly assist the pathologist. This study compares computer-assisted micrometastasis detection with routine detection by a pathologist. Cytokeratin-stained sentinel lymph node sections from 100 patients at the University of Vermont were evaluated by automated computer-assisted cell detection. Based on original routine light microscopy screening, 20 cases that were positive and 80 cases that were negative for micrometastases were selected. One-level (43 cases) or two-level (54 cases) cytokeratin-stained sections were examined per lymph node block. All 100 patients had previously been classified as node negative by using routine hematoxylin and eosin stained sections. Technical staining problems precluded computer-assisted cell detection scanning in three cases. Computer-assisted cell detection detected 19 of 20 (95.0%; 95% confidence interval, 75–100%) cases positive by routine light microscopy. Micrometastases missed by computer-assisted cell detection were caused by cells outside the instrument’s scanning region. Computer-assisted cell detection detected additional micrometastases, undetected by light microscopy, in 8 of 77 (10.4%; 95% confidence interval, 5–20%) cases. The computer-assisted cell detection–positive, light microscopy–missed detection rate was similar for cases with one (3 of 30; 10.0%) or two (5 of 47; 10.6%) cytokeratin sections. Metastases detected by routine light microscopy tended to be larger (0.01–0.50 mm) than did metastases detected only by computer-assisted cell detection (0.01–0.03 mm). In a selected series of patients, automated computer-assisted cell detection identified more micrometastases than were identified by routine light microscopy screening of cytokeratin-stained sections. Computer-assisted detection of events that are limited in number or size may be more reliable than detection by a pathologist using routine light microscopy. Factors such as human fatigue, incomplete section screening, and variable staining contribute to missing metastases by routine light microscopy screening. Metastases identified exclusively by computer-assisted cell detection tend to be extremely small, and the clinical significance of their identification is currently unknown.

Tyrosinase RT-PCR as a Supplement to Histology for Detecting Melanoma and Nevus Cells in Paraffin Sections of Sentinel Lymph Nodes

The detection of tyrosinase mRNA in sentinel lymph nodes (SLNs) by reverse transcription polymerase chain reaction (RT-PCR) is a sensitive indicator for the presence of melanoma or nevus cells, but it does not enable a distinction between both. We have established an efficient method for extraction and reverse transcription of tyrosinase mRNA from paraffin sections that permits the close correlation of the RT-PCR results with (immuno)histologic findings in adjacent sections. One hundred fifty-three SLNs and 6 non-SLN specimens originating from 92 melanoma and 4 nonmelanoma patients were studied to test the reliability of this approach. The predictive value of positive RT-PCR results was 0.98 for the presence of melanoma or nevus cells; the corresponding negative predictive value was 0.83. Furthermore, the detection rate of tyrosinase mRNA significantly correlated with tumor burden. Among the 33 melanoma-positive SLNs without nevus cells, positive RT-PCR results were obtained in all specimens with extended peripheral (S2) or deeply invasive (S3) micrometastases but in only 46% of the cases with few localized melanoma cells in the subcapsular zone (S1). Routine (immuno)histologic evaluation alone had missed microclusters of melanoma cells in one SLN and small nevus cell aggregates in six other SLNs. They were detected only during microscopic reexamination caused by a positive RT-PCR result. We conclude that histology and immunohistochemistry remain the indispensable gold standard for the identification of melanoma and nevus cells in SLNs. Additional molecular analyses using adjacent paraffin sections may further improve the diagnostic accuracy by sensitizing and guiding the microscopist’s attention.

Improved immunohistochemical evaluation of micrometastases in sentinel lymph nodes of cutaneous melanoma with 'MCW melanoma cocktail'--a mixture of monoclonal antibodies to MART-1, Melan-A, and tyrosinase.

BackgroundMART-1, Melan-A, and Tyrosinase have shown encouraging results for evaluation of melanoma micrometastases in sentinel lymph nodes, as compared to conventionally used S-100 protein and HMB-45. To achieve higher sensitivity, some studies recommend evaluation of three sections, each at intervals of 200 μ. This would mean, routine staining of three adjacent sections in each of the three clusters at intervals of 200 μ, requiring nine slides resulting in added expense. If a cocktail of these antibodies could be used, only one section would be required instead of three generating significant cost savings.MethodsWe prepared a combination of monoclonal antibodies to these three immunomarkers in optimized dilutions (MART-1, clone M2-7C10, dilution 1:500; Melan-A, clone A103, dilution 1:100; and Tyrosinase, clone T311, dilution 1:50) and designated it as 'MCW melanoma cocktail'. Formalin-fixed paraffin-embedded tissue sections of sentinel lymph nodes from patients with cutaneous melanoma, without macro-metastases were evaluated with this cocktail.ResultsMelanoma micrometastases were easily detectable with the cocktail in 41 out of 188 slices (8/24 cases). The diagnostic accuracy amongst five pathologists did not show statistically significant difference. Out of 188 slices, 78 had adjacent sections immunostained individually with MART-1 and Melan-A during our previous study. Of these 78 slices, 21 were positive for melanoma micrometastases with MART-1 and Melan-A individually. However, the adjacent section of these slices immunostained with the cocktail detected metastases in four additional slices. Thus, MART-1 and Melan-A could not detect melanoma micrometastases individually in 16% (4/25) of slices positive with the cocktail. Benign capsular nevi were immunoreactive for the cocktail in 4.8% (9/188) slices. All 81 slices of negative test controls (sentinel lymph nodes of mammary carcinoma) were interpreted correctly as negative for melanoma micrometastases.ConclusionsThe melanoma cocktail facilitated easy interpretation of melanoma micrometastases in sentinel lymph nodes with high interobserver agreement. There was improvement in detection rate with the cocktail as compared to MART-1 and Melan-A individually. Furthermore, this approach facilitates cost savings.

Sentinel Node Biopsy in Gastric Cancer: Preliminary Results

Background: Extent of lymphadenectomy in gastric cancer is one of the still unresolved and ongoing questions. Whether extensive procedures lead to better survival remains controversial. The detection of sentinel node could become a helpful method to define the desirable extent of lymph node dissection for each particular patient. Material and methods: Prospective, single-centre, clinical trial. Sentinel node is identified using vital blue dye. After performance of D2 lymphadenectomy, the pathologist minutely investigates all lymphatic nodes by histological and imunohistochemistry techniques.Results: During a period of 36 months, an attempt to localise the sentinel node for biopsy was made in 22 patients. The successful rate of sentinel node detection with a good relation between metastatic involvement of the sentinel node and other nodes was 56% (13 out of 22 patients). All these patients suffered from small tumours and early stage of the disease. In large tumours and advanced stages, blue dye stained the tissue around the tumour diffusely rendering the identification of true sentinel node impossible. Fresh frozen section of the sentinel node resulted in two patients in a false negative outcome because of micrometastatic involvement.Conclusions: Sentinel node biopsy in gastric cancer using vital staining is a feasible method. Reliable results were seen in early stage of the disease. Fresh frozen section of sentinel node has probably a low sensitivity for detection of micro-metastases.

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The detection of occult metastatic breast cancer cells by RT-PCR is limited by the poor specificity of most tumour mRNA markers. MAGE-A3 is a highly specific tumour mRNA marker that is not expressed in non-cancer cells. This study assesses MAGE-A3 mRNA as a molecular marker for the detection of tumour cells in the sentinel lymph nodes (SLN) of breast cancer patients. Serial frozen sections of SLN (n= 121) were obtained from 77 AJCC (American Joint Committee on Cancer) Stage I–IIIA breast cancer patients. MAGE-A3 mRNA analysis of SLN was performed by RT-PCR and Southern blot analysis. Tumour cells were detected in 48 of 121 (40%) SLN from 77 patients by H&E or IHC staining, and 35 of 77 (45%) patients, overall, had histopathologically (H&E and/or IHC) positive SLN. Among histopathologically negative SLN, 28 of 73 (38%) SLN were MAGE-A3 mRNA positive by RT-PCR. Overall, 41 of 77 (53%) patients and 50 of 121 (41%) SLN were positive for MAGE-A3. MAGE-A3 mRNA expression in the SLN occurred more frequently with infiltrating lobular carcinoma (P< 0.001) than with infiltrating ductal carcinoma, adding further evidence of possible phenotypic differences between these 2 subtypes of breast cancer. Due to its high specificity, MAGE-A3 mRNA is a potentially useful marker for detecting breast cancer cells in the SLN. One half of breast tumours expressed MAGE-A3 mRNA, which has important potential implications for antigen-specific targeted immunotherapy. © 2001 Cancer Research Campaign http://www.bjcancer.com

Detection of MAGE-A3 in breast cancer patients' sentinel lymph nodes.

The detection of occult metastatic breast cancer cells by RT-PCR is limited by the poor specificity of most tumour mRNA markers. MAGE-A3 is a highly specific tumour mRNA marker that is not expressed in non-cancer cells. This study assesses MAGE-A3 mRNA as a molecular marker for the detection of tumour cells in the sentinel lymph nodes (SLN) of breast cancer patients. Serial frozen sections of SLN (n= 121) were obtained from 77 AJCC (American Joint Committee on Cancer) Stage I–IIIA breast cancer patients. MAGE-A3 mRNA analysis of SLN was performed by RT-PCR and Southern blot analysis. Tumour cells were detected in 48 of 121 (40%) SLN from 77 patients by H&E or IHC staining, and 35 of 77 (45%) patients, overall, had histopathologically (H&E and/or IHC) positive SLN. Among histopathologically negative SLN, 28 of 73 (38%) SLN were MAGE-A3 mRNA positive by RT-PCR. Overall, 41 of 77 (53%) patients and 50 of 121 (41%) SLN were positive for MAGE-A3. MAGE-A3 mRNA expression in the SLN occurred more frequently with infiltrating lobular carcinoma (P< 0.001) than with infiltrating ductal carcinoma, adding further evidence of possible phenotypic differences between these 2 subtypes of breast cancer. Due to its high specificity, MAGE-A3 mRNA is a potentially useful marker for detecting breast cancer cells in the SLN. One half of breast tumours expressed MAGE-A3 mRNA, which has important potential implications for antigen-specific targeted immunotherapy. © 2001 Cancer Research Campaign