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.
Contractor
K
K
Northwick Park and St Mark's Hospital NHS Trust, Watford Road, Harrow, London, UK.
Gohel
M
M
Al-Salami
E
E
Kaur
K
K
Aqel
N
N
Nigar
E
E
Burke
M
M
Singhal
H
H
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*