Role of imprint cytology in the intraoperative evaluation of sentinel lymph nodes for malignant melanoma

Controversy exists over the utility of different methods for intra-operative sentinel lymph node (SLN) evaluation in patients with malignant melanoma (MM). The aim of this study was to evaluate the role of intra-operative imprint cytology (IC) in patients with MM. 215 SLNs from 99 patients with MM were examined by IC and results compared with the results of permanent sections. 24 patients had MM deposits in their SLNs and this was confirmed by histological examination. Intraoperative IC was positive in 11 of these patients (46% sensitivity). In addition, there were three false-positive IC diagnoses (79% positive predictive value); one of these was due to contamination during the sectioning of the SLN. The specificity and the negative predictive values of the IC were 96 and 85%, respectively. IC is a valuable method of intra-operative SLN evaluation which can spare approximately half of the patients with clinically occult regional metastases from a second surgical procedure. However, special care must be taken to avoid false-positive results due to contamination.     

Intraoperative imprint cytology of sentinel nodes in breast cancer

BACKGROUND AND OBJECTIVES: Sentinel node (SN) biopsy is a new standard of care for axillary node staging in patients with early-stage, clinically node-negative breast cancer. A second operation can be avoided when the results are available intraoperatively. However, there is no standard intraoperative method for SN assessment. The aim of this study was to evaluate intraoperative imprint cytology (IC) for the detection of SN involvement in patients with early-stage breast cancer. METHODS: One hundred eighty-five consecutive patients with a breast tumor underwent SN biopsy with intraoperative IC. The SN was bisected and a touch preparation was made with a glass slide, on both sides of the cut. Permanent sections were evaluated with H&E and immunohistochemical staining. The IC results were compared with the final histologic results. RESULTS: The sensitivity, specificity, accuracy, and positive and negative predictive values of IC were 33.3, 78.4, 78.9, 90, and 77.5%, respectively. IC was more sensitive for macrometastases than for micrometastases. In the 118 patients studied after the learning phase, 9 patients with a positive SN by IC avoided a second operation. CONCLUSIONS: Intraoperative IC of SNs appears to be reasonably reliable in patients with breast cancer, permitting axillary dissection during the same surgical procedure when positive. In contrast, sensitivity for detection of micrometastases is low.     

Intraoperative evaluation of axillary sentinel lymph nodes using touch imprint cytology and immunohistochemistry. Part II. Results.

AIM: In order to operate selectively on positive axillae during the initial operative session for early breast cancer, an accurate and rapid intraoperative method to examine an axillary node sample (ANS) or a sentinel node biopsy (SNB) is required. The aim of this study was to determine the feasibility and accuracy of Immunohistochemistry (IHC)-stained touch imprints in detecting metastatic axillary nodes intraoperatively. MATERIAL AND METHODS: Four hundred and thirty-two axillary nodes from 52 patients (23 axillary node clearance (ANC), 15 ANS and 14 SNB) were bisected, imprinted and stained with anti-cytokeratin 19 IHC. Results were compared with those of routine haematoxylin and eosin (H&E)-stained sections. RESULTS: IHC imprints detected 32 positive nodes from 12 patients. H&E sections detected 31 positive nodes from 11 patients. IHC imprints missed metastases in three nodes and missed the diagnosis of positive axillae in two patients. H&E missed metastases in four nodes and missed the diagnosis of positive axillae in 3 patients. On a node-basis, sensitivities were 91.4 and 88.5%, negative predictive values (NPV) were 99.2 and 99.0% and overall accuracies were 99.3 and 99.1% for IHC imprints and H&E sections, respectively. On a patient-basis, sensitivities were 85.7 and 78.5%, NPVs were 95.2 and 93.1% and overall accuracies were 96.1 and 94.2% for IHC imprints and H&E sections respectively. There were no false positives. Interpretation of the results by a non-histopathologist was concordant with that of a histopathologist. Results might be obtained within 30-45 min depending on the number of examined nodes. CONCLUSION: Intraoperative IHC staining of touch imprints of axillary sentinel nodes is feasible and is a reliable method for evaluating axillary nodes. Slides can be reliably interpreted by a trained non-histopathologist.     

Intraoperative touch imprint of sentinel lymph nodes in breast carcinoma patients

BACKGROUND: Sentinel lymph node examination in patients with breast carcinoma has been gaining in popularity. Currently, there is no standard intraoperative assessment of sentinel lymph nodes. To assess the utility of an intraoperative touch imprint (TI) evaluation, the authors compared TI cytology with surface hematoxylin and eosin (H&E) histology in sentinel lymph nodes from patients with breast carcinoma. METHODS: Sixty five sentinel lymph node biopsy cases were identified. Diagnoses from TI and surface H&E histologic sections were compared. RESULTS: Touch imprint had a specificity of 100%, a negative predictive value of 88%, a sensitivity of 65%, and a false negative rate of 9% per sentinel lymph node biopsy case. Eighty three percent of the false negative TI cases were due to micrometastasis. Preoperative chemotherapy, primary tumor type, and primary tumor size did not significantly contribute to false negative events. Touch imprint identified 67% of the cases that required completion axillary dissection. CONCLUSIONS: Touch imprint is a reliable and accurate intraoperative technique, with the potential to save a significant number of patients morbidity and the cost of a second surgical procedure to remove axillary lymph nodes. The difficulty of identifying micrometastases appeared to be the major source of false negative events, a problem that is not unique to TI cytology.     

Intraoperative touch imprint cytology of sentinel lymph nodes in breast cancer: experience at a tertiary care center in Mexico

Background Sentinel lymph node (SLN) biopsy in patients with breast cancer has emerged as a conservative and promising procedure. One of the most important issues is the intraoperative evaluation of the SLN with a high degree of accuracy by frozen section and/or imprint cytology. The objective of this study was to test the ability of intraoperative touch imprint cytology (ITIC) to predict metastasis on SLN. Methods SLNs were freshly examined, bisected in <0.5 cm or serially sectioned at 2 mm intervals on the long axis. Each surface of the section was touched on the glass slide, and stained. Results of ITIC were compared with permanent sections. Sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), and accuracy (Acc) were calculated. False negatives were reviewed. Results We analyzed 179 SLN from 110 patients. The comparison between ITIC and final results of the SLN showed 139 (77.6%) true negative imprints, and 28 (15.6%) true positive. There were 12 (6.70%) false negative (FN) imprints which included 6 macrometastases, 3 micrometastases, and 3 isolated tumor cells. Re-screening after the definitive results of false negative imprints showed again 10 negative imprints, one with two groups of cells and one with multiple groups of cells. The overall Se was 70% (73.6% for micro/macrometastases and 82.3% for macrometastases), Sp and PPV were 100% in all cases. NPV was 92.1% overall (93.4% micro/macrometastases and 96% in macrometastases).Global accuracy was 93.3% (94.4% for micro/macrometastases and 96% for in macrometastases). Conclusions ITIC is excellent to detect macrometastases, however, it fails to detect micrometastases. False negative imprints for macrometastases are mainly due to sampling error. The immediate availability, low cost, high Sp, PPV, preservation of the lymph node for histopathologic examination, avoiding of a second surgery are the major advantages of intraoperative evaluation of SLN.     

Intraoperative evaluation of axillary sentinel lymph nodes using touch imprint cytology and immunohistochemistry: I. Protocol of rapid immunostaining of touch imprints.

AIMS: Sentinel Node Biopsy (SNB) is considered an accurate method of detecting axillary lymph node status in patients with small breast cancer. Combined with an accurate and rapid histopathology tool, it could spare this group of patients unnecessary Axillary Node Clearance (ANC) with its associated hazards. Intraoperative examination of SNB for cancer cells has been investigated using both Frozen Sections (FS) and Imprint Cytology (IC) stained with different stains. This study is devoted to establish a reliable and rapid protocol for immunostaining of touch imprints from SNB. METHODS:We investigated two different EPOS (Enhanced Polymer One-Step staining--DAKO) anticytokeratin antibodies, five different tissue fixatives and different incubation periods and temperatures with both positive and negative controls. RESULTS: We have developed a protocol, which produced good and consistent immunostaining of touch imprints. The initial results using this protocol are concordant with those of permanent Haematoxylin and Eosin (H&E) sections. CONCLUSIONS: We propose this protocol for rapid immunostaining of touch imprints of SNB.     

乳腺癌术中前哨淋巴结印片细胞学的评估

乳腺癌的手术治疗发生了巨大的变化,前哨淋巴结活检是其中之一。前哨淋巴结活检可准确评估区域淋巴结状态,从而避免在腋淋巴结阴性乳腺癌中行腋淋巴结清扫术,减少手术的并发症。乳腺癌前哨淋巴结术中病理学诊断是目前限制前哨淋巴结发展成为乳腺癌的手术规范的主要原因之一,如果能够进行准确地术中诊断,就可以避免再次手术。本文对乳腺癌前哨淋巴结的术中诊断的两种主要方法印片细胞学与冷冻切片的优缺点进行比较,回顾相关机构进行术中诊断的研究结果,并且对印片对诊断前哨淋巴结中存在的问题以及可能改进的方向进行初步的探讨。     

Feasibility of imprint cytology for evaluation of mediastinal lymph nodes in lung cancer

BACKGROUND: Intraoperative evaluation of mediastinal lymph nodes is a necessary step which helps us to decide whether or not to continue the operation of lung cancer. Imprint cytology (IC) can be used as an alternative method in staging. It is a more rapid and simpler procedure than frozen section (FS) analysis. Therefore, we compared the diagnostic accuracy of IC with permanent section on 1050 mediastinal lymph nodes. METHODS: A total of 255 non-small cell lung cancer patients who underwent surgical procedure between January 1995 and April 2004 were included. There were 236 males and 19 females with a mean age of 54.2 years (range 26-79 years). In order to obtain lymph node samples mediastinoscopy was performed in 232 (91%), anterior mediastinotomy in 50 (20%) and video-assisted thoracoscopic surgery in 16 (6.3%) patients. During final pathological diagnosis, both imprint and permanent section slides were compared. RESULTS: There were five false-positive and eight false-negative results. The sensitivity, specificity and the predictive values for positive and negative results were 93.1, 99.5, 95.6 and 99.1%, respectively. The overall efficiency was 98.8%. CONCLUSIONS: The diagnostic IC is an accurate, reliable, simple and less time-consuming method for evaluation of mediastinal lymph nodes in lung cancer, compared with FS method.     

Accuracy of intraoperative imprint cytology of sentinel lymph nodes in cT1 infiltrating breast cancer

BackgroundIntraoperative examination of sentinel lymph nodes (SLN) in breast cancer can avoid a new surgical procedure in case of positive SLN, but its value, efficacy and the methods used are still controversial. The aim of our study was to evaluate the imprint cytology intraoperative method of SLN analysis performed at our institution.MethodsWe did a retrospective study of the sentinel lymph node procedures performed during a period of 24 months on cT1N0 unifocal breast cancers. Intraoperative procedure was mainly by imprint cytology (touch prep).ResultsA SLN procedure was performed on 187 women with 360 SLN. Two hundred and seventy-seven SLN among 156 women were analyzed intraoperatively by touch prep. 19/48 positive SLN were detected by intraoperative touch prep (sensitivity 39.6%; specificity 100%; positive predictive value 100%; negative predictive value 88.7%, accuracy 89.5%). False negative rate of cytological intraoperative examination of SLN was 11,2% by SLN and 18,3% by patient. By univariate analysis, this rate significantly increased with lymphovascular invasion, tumor size cT1b and c and histological SBR grade 2 or 3. By multivariate analysis, only lymphovascular invasion was a predictive factor of intraoperative touch prep failure (OR = 3.3; IC 1.3-8.4).ConclusionIntraoperative imprint cytology of SLN in breast cancer is associated with a high rate of false negativity that questions its use in this setting.     

Intraoperative touch imprint cytological analysis of sentinel lymph nodes for the presence of metastases in breast cancer

BACKGROUND: Imprint cytology may provide a fast and accurate method for intraoperative screening of sentinel lymph nodes, so a decision can be made regarding whether to perform axillary clearance during primary surgery. If the findings are negative, in many cases axillary dissection can be omitted. Patients and METHODS: 128 sentinel nodes from a cohort of 87 patients that had been identified using technetium-99m nanocolloid as a radioactive tracer and Patent blue dye were dissected for rapid Diff-Quick stained touch preparations. Intraoperative evaluation of sentinel node status by imprint cytology was correlated with histopathological results of permanent sections. Tumor-negative nodes in routine paraffin sections were further investigated with the employment of an anti-cytokeratin antibody. RESULTS: 36 of all sentinel nodes harbored metastases in the paraffin sections, of which 32 were identified by imprint cytology (sensitivity 88.8%). 3 sentinel nodes were positive by imprint cytology and negative by histopathology of the paraffin sections. Comparison of the results of the touch preparations with the final histopathology (hematoxylin-eosin and anticytokeratin antibody stains) demonstrated a sensitivity of 83.3% and a negative predictive value of 92.5%. The specificity and positive predictive value were 100% each. CONCLUSIONS: Touch imprint cytology is potentially useful for intraoperative evaluation of sentinel lymph nodes in breast cancer patients.     

Intraoperative assessment of sentinel lymph nodes in patients with breast carcinoma: accuracy of rapid imprint cytology compared with definitive histologic workup

BACKGROUND: As sentinel lymph node biopsy (SNB) becomes a new surgical standard in the treatment of patients with breast carcinoma, there is an emergent need for a fast and accurate method with which to assess the SN intraoperatively, so a decision can be made regarding whether to perform axillary lymph node dissection during primary surgery. In the current study, the authors performed a prospective investigation of the relative merits of imprint cytology for that purpose.METHODS: Seventy-six patients with T1-T2 breast carcinoma were included after undergoing successful SNB. SNs were freshly sectioned at 2-mm intervals and imprint smears were obtained from all cut surfaces. The smears were examined using a rapid May-Grünwald-Giemsa stain variation, and the SNs were judged to be positive or negative for metastases. SNs later were submitted for paraffin embedding and serial sectioning. Both hematoxylin and eosin stained and cytokeratin (CK) immunostained sections were examined. The postoperative evaluation of the SNs was taken as the gold standard.RESULTS: Intraoperative cytology showed a sensitivity of 67.7%, a specificity of 100%, an accuracy of 86.8%, and a negative predictive value of 81.8%. The majority of false-negative cases (8 of 10 cases) were due to micrometastasis in the SNs that were discovered only after exhaustive examination with serial sectioning and CK immunostaining.CONCLUSIONS: The results of the current study demonstrate that the accuracy of imprint cytology is high enough to warrant its use for intraoperative SN assessment. If the findings are negative, axillary lymph node dissection can be omitted. Only a few patients with SN micrometastasis may require reoperation.     

Touch imprint cytology and immunohistochemistry for the assessment of sentinel lymph nodes in patients with breast cancer

AIMS: Accurate evaluation of sentinel nodes is of clinical importance to avoid further surgery for axillary node dissection. A prospective study was carried out to investigate the feasibility and accuracy of touch imprint cytology (TIC) and touch imprint immunohistochemistry (TIHC). METHODS: Two hundred and five sentinel nodes from consecutive 118 patients with primary breast cancer were studied after successful identification of sentinel nodes. Sentinel nodes were sectioned at 2 mm intervals and imprint specimens prepared from all cut surfaces were subjected to Papanicolaou staining and immunohistochemical staining using anti-cytokeratin antibody. RESULTS: Forty-nine sentinel nodes from 40 patients were positive by permanent section. The sensitivity of TIC was 84% (41/49) per sentinel node and 83% (33/40) on a per patient basis. The sensitivity of TIHC was 86% (42/49) per sentinel node and 83% (33/40) on a per patient basis. When the results of TIC and TIHC were combined, the sensitivity was 88% (43/49) per sentinel node and 85% (34/40) on a per patient basis. Among the 156 negative sentinel nodes, four sentinel nodes from four different patients were consistently positive by TIC and TIHC, but only one patient out of 78 node-negative patients was upstaged. CONCLUSIONS: Touch imprint cytology is sufficiently sensitive for intraoperative evaluation of sentinel nodes. A slight improvement in the sensitivity is expected when immunohistochemistry is used. The combination of these methods provides better sensitivity than either method alone.     

Intraoperative sentinel lymph node examination by frozen section, immunohistochemistry and imprint cytology during breast surgery--a prospective study

The aim of this study was to compare the sensitivity of intraoperative frozen section with hematoxyllin-eosin (H&E) staining, immunohistochemistry (IHC) or imprint cytology (IC) in the analysis of sentinel node (SN) in breast cancer. Towards this end, a prospective study of 102 patients undergoing mastectomy or sector resection with SN biopsy was conducted. Frozen sections of SN with H&E, IHC staining and IC had sensitivities of 73.5%, 75.5% and 51.0%, respectively. The combination of H&E and IHC raised the overall sensitivity to 83.7%. Macrometastases (>2 mm) were detected in 100% of the cases with H&E, 92.6% with IHC and 81.5% with IC; and micrometastases (2 mm) in 35.0%, 45.0% and 5.0%, respectively. The combination of H&E and IHC staining raised the sensitivity to 55.0%. Frozen-section analysis with H&E staining showed high sensitivity in detecting macrometastases but not micrometastases. The sensitivity for detection of micrometastases was not substantially increased by the use of intraoperative IHC. Imprint cytology did not provide any additional information.     

Factors associated with the misdiagnosis of sentinel lymph nodes using touch imprint cytology for early stage breast cancer

Accurate intraoperative diagnosis of sentinel node metastasis enables the surgeon to make an immediate decision to proceed to axillary lymph node dissection (ALND), thereby avoiding the economic and psychological costs of a second operation. The present study aimed to evaluate the clinical value of touch imprint cytology (TIC) and investigate the potential factors associated with misdiagnosis. A total of 366 patients with Tis-T2 breast carcinoma were included after undergoing successful sentinel lymph node biopsy (SLNB). TIC was routinely performed intraoperatively, and the results were compared with definitive histological assessments of serial sections (SS) with hematoxylin and eosin (H&E) staining. A total of 992 SLNs from 366 patients were used in the study. Based on the final histological diagnosis, the sensitivity, specificity and overall accuracy of TIC was 76.6, 98.8 and 92.3%, respectively, on a per patient basis, and 79.9, 98.9 and 96.1%, respectively, on a per node basis. TIC was significantly more sensitive for macrometastasis than micrometastasis (80.0 vs. 28.6%, P<0.01). Of 9 total 'false positives', 3 were due to micrometastasis which were not identified by serial section with H&E staining, 4 were actual false-positives which were due to interpretation error, and 2 were due to sampling error. The majority of the false-negatives (28 of 30 SLNs) were due to micrometastasis in the SLNs (sampling error). In conclusion, TIC is feasible for clinical use and is able to detect macrometastasis in the SLNs of early stage invasive breast cancer patients with an acceptable accuracy while its ability to detect micrometastasis is limited.     

Accuracy of intraoperative imprint cytology for sentinel lymph node evaluation in the treatment of breast carcinoma

BACKGROUND: The current report provides results from a large retrospective analysis of intraoperative imprint cytology performed on axillary sentinel lymph nodes (IIC(N)) removed over the course of 2137 breast surgeries (4905 lymph nodes). It is hoped that these results may serve as benchmarks for those interested in using this technique. METHODS: The current study included 2078 patients with T1-2 invasive breast carcinoma who underwent sentinel lymph node biopsy (SLNB) and IIC(N). Lymph nodes were bivalved, imprinted, stained with Diff-Quik (Baxter Diagnostics, McGaw Park, IL), and reviewed by a cytopathologist. A positive intraoperative diagnosis led to immediate complete axillary lymph node dissection (CALND). On final pathology, lymph nodes found to be negative on hematoxylin and eosin staining were submitted for cytokeratin staining. RESULTS: Of the 2137 cases for which SLNB was performed, 673 were found to have positive lymph node status on final pathology. Of these 673 cases, 359 were identified by IIC(N), resulting in a sensitivity rate of 53.3%. The specificity and overall accuracy rates for this technique were 99.5% and 85.0%, respectively. In IDC cases, IIC(N) had a sensitivity rate of 55.5%, compared with 38.7% in ILC cases. Based on these results, the reoperative CALND rate was calculated to be approximately 14.7%, with 54.5% of these reoperative procedures being performed for cases in which lymph nodes positive only for micrometastases were found. Macrometastasis-positive lymph nodes that went undetected by IIC(N) were present in only 154 of the 2137 cases examined (7.2%). CONCLUSIONS: IIC(N) accurately predicts final lymph node status in 85.0% of patients. Although the accuracy of this technique varies with tumor size and type, IIC(N) remains a time-efficient and cost-effective adjunct to SLNB.     

Intraoperative imprint cytology for the diagnosis of sentinel node metastases in breast cancer

Accurate intraoperative diagnosis of sentinel node metastases enables the selection of patients for axillary lymph node dissection, thus avoiding an unnecessary additional operation in patients with false-negative results. The main reason for false-negative results of imprint cytology was poor quality of the imprint samples because of sampling error. False-positive imprint cytology results that lead to an unnecessary axillary lymph node dissection are very rare. Imprint cytology can be recommended for the intraoperative examination of sentinel nodes in breast cancer patients.