Sentinel lymph node biopsy: An audit of intraoperative assessment after introduction of a cytotechnology service

Objective: To audit results from intraoperative assessment of sentinel lymph node biopsy (SLNB) after the introduction of a cytotechnologist. Study design: Since 2010, a cytotechnologist has been involved in the intraoperative assessment of SLNB in our breast cancer patients. The data from patients over the period 2006 - 2013 were used to compare outcomes before and after the introduction of a cytotechnology service. The database was divided into the periods 2006 - 2008 and 2010 - 2013 (2009 was the training period). Results: A total of 335 intraoperative SLNB assessments were performed: 165 between 2006 and 2008 (group 1) and 170 between 2010 and 2013 (group 2). In the study period (2010 - 2013), 2 (1%) metastatic deposits >2 mm were missed in patients with lobular carcinoma and 1 in a patient with ductal carcinoma. There was one (0.6%) false positive in a patient with a lobular carcinoma in each group. For patients with metastases >2 mm, group 1 had a sensitivity of 87% and a specificity of 99%. Group 2 had a sensitivity of 92% and a specificity of 99%. Conclusion: A trained cytotechnologist performing imprint cytology on SLNB to determine metastatic breast cancer can deliver results comparable with those of a group of pathologists.