The reliability and accuracy of intraoperative imprint cytology of sentinel lymph nodes in breast cancer.

OBJECTIVE: Sentinel lymph node (SLN) biopsy is a new component of the surgical treatment of breast cancer that accurately predicts axillary status. In this study the authors evaluated the accuracy of intraoperative imprint cytology (IC) in comparison with definitive histologic evaluation of SLN in breast cancer patients. METHODS: A total 413 women with breast carcinoma and clinically negative axillary nodes underwent breast surgery and SLN biopsy. Mapping of SLN involved injection of (99m)Technecium labelled human albumin nanocolloid particles and Patent Blue dye. At the Department of Pathology, SLNs were bisected along its major axis. Both halves were imprinted 2-4 times on the slides and immediate staining with Hemacolor (Merck Germany) was performed for intraoperative examination. Imprint node negative women underwent no further surgery, while node positive women proceeded to full axillary clearance. Histological analysis of the SLN involved serial sectioning of the whole node with H&E and immunostaining for cytokeratin. RESULTS: Definitive histology revealed metastases (pN+) in 159/413 patients (38.5%): 69 (16.7%) macro metastases, 57 (13.8%) micro metastases, and 33 (8%) women with only isolated IHC positive cells or positive cell groups smaller than 0.2 mm (pNO sn+). The other 254 women had negative SLN biopsy. Imprint cytology detected 54/69 macro metastases, and 4/57 micro metastases. In the group with negative SLN (254), 2 cases were ''false positives''. CONCLUSIONS: Imprint of SLN biopsy can identify a negative axilla with high accuracy (specificity 99.2%). Overall sensitivity is only 36.5%, but macrometastases are detected in 77% which is important for performing ALDN in one session with operation of primary tumour.

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.

Added value of blue dye in sentinel node biopsy for breast cancer.

Sentinel node biopsy in breast cancer is a new rapidly advancing minimal invasive procedure which enables nodal staging of clinically node negative breast cancer patients without performing complete axillary dissection. There are still controversies over the added value of Blue Dye when lymphoscintigraphy and gamma probe are used. In our series, 91 consecutive patients with invasive breast carcinoma were operated by a single surgeon, using lymphoscintigraphy, gamma probe and Blue Dye. The sentinel nodes (SLN) were histologically examined by HE and immunohistochemistry. Lymphoscintigraphy was succesful in 81 patients (89%). After the injection of Blue Dye, SLN could be identified in all 91 patients. Metastases in the SLN were present in 35 patients. We retrieved 128 SLN, of these 93 were hot and blue, 19 only hot and 16 only blue. The distribution of metastatic and nonmetastatic SLN between these three labeling groups was not different (P = 0.9361). We could not show any difference in the metastatic involvement of SLN in patients in whom preoperative lymphoscintigraphy could visualise the SLN preoperatively compared to those in whom it could not (P = 0.7315). False negativity calculated in our initial series of 36 patients was 0%. Our study showed added value of Blue Dye in detection of metastatic and nonmetastatic SLN.