How Many Tumor Cells in the Intraoperative Imprint Cytology of Sentinel Lymph Nodes Are Enough To Diagnose Metastatic Breast Carcinomas?
Mei-Ling Wu, Shu-Chuan Yang, Wen-Chia Hsieh, Hsiao-Ting Wang, Min-Hua Huang, Siou-Ling Ciou, Ai-Ying Chuang. Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan
Background: Intraoperative imprint cytology examination (ICE) of sentinel lymph nodes (SLNs) is widely used in detecting metastatic breast carcinomas. Occasionally, few cases with tumor cells detected in the ICE have no or <=0.2mm isolated tumor cells on the H&E and/or IHC sections, which will be classified as no LN metastasis in the AJCC staging system.
Design: From 2007 to 2010, all ICE signed out as atypical cells, suspicious of malignancy or metastatic carcinomas were reviewed. On review, cases with crushed lymphocytes, histiocytes, and/or endothelium which were originally misdiagnosed as atypical cells were excluded. The numbers of the tumor clusters/single cells and the size of the largest tumor cluster were recorded. The aim of this study was to evaluate how many tumor cells in the ICE having >0.2mm metastatic carcinomas on the permanent sections. To avoid false positive, 100% specificity is the goal.
Results: Three hundred and nine SLNs from 253 patients (IDC: 218, ILC: 10, mixed invasive ductal and lobular carcinomas: 16, tubular carcinoma: 1, invasive papillary carcinoma: 3, metaplastic carcinoma: 2, DCIS: 2, DCIS with microinvasion: 4) had tumor cells in the ICE. There were 217 SLNs having >= 30 tumor clusters/single cells. The numbers of tumor clusters/single cells in remaining 92 SLNs ranged from 1 to 28 (mean 9.4, median 7.5). The size of the largest tumor cluster in each SLN ranged from 0.02mm to 8mm (mean 0.75, median 0.4).
Among 22 SLNs with no or <=0.2mm isolated tumor cells on the H&E and/or IHC sections, the highest number of tumor clusters/single cells is 15 (range 1-15), and the size of largest tumor cluster is 0.28mm (range 0.03-0.28). Using the number of tumor clusters/single cells > 15 could achieve a sensitivity of 83.6% in predicting metastasis (specificity 100%). If using tumor cluster size >=0.3mm as an add-on criteria, we can increase the sensitivity to 84.7%.
Using the number of tumor clusters/single cells >10 could achieve a sensitivity of 86.8 % in predicting metastasis (specificity 95.5%). If using tumor cluster size >=0.3mm as an add-on criteria, we can increase the sensitivity to 87.1%.
Conclusions: To predict metastasis in breast cancer patients using intraoperative imprint cytology of sentinel lymph nodes, the sensitivity is 83.6% when number of tumor clusters/single cells is >15. Combing the size of the largest tumor cluster does not significantly increase the sensitivity of prediction metastasis.
Wednesday, March 21, 2012 9:30 AM
Poster Session V # 20, Wednesday Morning