Intra-operative imprint cytology for assessing the sentinel node in breast cancer: results of its routine use over 8 years.
BACKGROUND
Intra-operative imprint cytology (IIC) for analysing sentinel lymph node/s (SLN) in breast cancer allows definitive axillary surgery as a one-step procedure. Most reported studies are research oriented. This study reports long-term results of IIC done as routine clinical practice.


METHODS
Eight hundred ninety-six female, operable breast cancer patients underwent SLN biopsy over an 8-year period (January 1999-December 2006). Data were extracted retrospectively from medical records. SLNs were sent intra-operatively to the laboratory where they were bisected, touch imprinted and stained with Hematoxylin & Eosin. Patients with positive IIC had axillary clearance. Formal histological analyses of SLNs were compared with IIC findings. The impact of routine pre-operative axillary ultrasound (introduced in 2003) on IIC sensitivity and specificity was also assessed.


RESULTS
Median age was 61 years (26-89) and median tumour size was 18 mm (2-100). A total of 244/896 patients had SLN metastases on final paraffin histology of which 177 were correctly detected by IIC (67 false negatives). 39/67 false negatives could be attributed to sampling error. The overall sensitivity and specificity of IIC for the identification of SLN metastases was 73% and 100%, respectively. The sensitivity of IIC after introduction of pre-operative axillary ultrasound decreased from 75% to 71%.


CONCLUSIONS
Routine use of IIC for analysis of the SLN in breast cancer allows complete axillary surgery during a single anaesthetic for a majority of patients undergoing SLN biopsy. Almost two thirds of positive axillae were spared a second operation. False negative results are frequent and patients should be warned about the potential need for further axillary surgery.
Northwick Park and St Mark's Hospital NHS Trust, Watford Road, Harrow, London, UK.
K
K
Contractor
M
M
Gohel
E
E
Al-Salami
K
K
Kaur
N
N
Aqel
E
E
Nigar
M
M
Burke
H
H
Singhal
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001365:Axilla; D001943:Breast Neoplasms / Q000473:pathology*; D003584:Cytological Techniques; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology / Q000601:surgery; D008207:Lymphatic Metastasis / Q000473:pathology*; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*