A single institutional experience of factors affecting successful identification of sentinel lymph node in breast cancer patients.
BACKGROUND
Sentinel lymph node biopsy (SLNB) has become the standard of care in axillary staging of clinically node-negative breast cancer patients. We hypothesized that certain clinical parameters are associated with failure to identify a SLN.


METHODS
We performed an institutional review board-approved, retrospective analysis of 402 consecutive breast cancer patients who underwent SLNB from 2000 to 2007.


RESULTS
Of 402 patients, 399 had lymphoscintigraphy (LSG) performed at the time of radiocolloid injection. No significant differences in successful identification of a SLN were found with respect to patient age, histology, or pathologic status of the SLN. Thirteen of 27 patients with no nodes imaged on LSG failed to have a SLN identified at surgery, whereas only 8 of 372 patients with positive imaging on LSG failed to have a SLN identified at surgery (P < .0001). Patients with a body mass index (BMI) > or =40 had a significantly higher rate of failure to detect a SLN by LSG (5/29 patients) compared with patients with a normal BMI (4/145 patients; P < .01). There was a trend for association with increasing BMI and failure to identify a SLN at surgery. The rate of failure to identify a SLN demonstrated a significant improvement in LSG after 200 patients and in surgical success after 100 patients (P < .001).


CONCLUSIONS
Successful identification of a SLN was influenced by BMI, institutional experience, and successful imaging by LSG. After gaining appropriate experience, the probability of successfully identifying a SLN at the time of surgery in a patient with BMI <40 who imaged on LSG was 99.7%.
Department of Surgery, University of Iowa, Iowa City, IA 52242, USA.
Matthew T
MT
Johnson
Julie A
JA
Guidroz
Brian J
BJ
Smith
Michael M
MM
Graham
Carol E H
CE
Scott-Conner
Sonia L
SL
Sugg
Ronald J
RJ
Weigel
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008875:Middle Aged; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D021701:Sentinel Lymph Node Biopsy