Factors associated with detection failure and false-negative sentinel node biopsy findings in gastric cancer: results of prospective single center trials.

BACKGROUND AND OBJECTIVES: The factors associated with successful sentinel node biopsy (SNB) are limited in gastric cancer despite a wide range of sensitivities reported. This study was performed to identify the factors associated with detection failure and SNB false-negativity in gastric cancer.
METHODS: SNB was performed on 156 gastric cancer patients from May 2002 to April 2007 at the Korean National Cancer Center during three consecutive prospective trials. Indications for SNB were determined preoperatively in cT1-2N0 patients. Dissected SNs and non-SNs after D2 lymphadenectomy were pathologically evaluated for metastasis. Clinical, pathological, and technical factors were analyzed for detection failure and false-negativity.
RESULTS: SNs were detected in 147 patients (94.2%) and the median number of SNs detected per patient was 3 (1-12). Twenty-five of 37 with nodal metastasis were diagnosed by SNB (sensitivity, 67.6%). Surgeon's inexperience (<or=30 procedures) and a male patient gender were significantly associated with detection failure (P = 0.014 and 0.031, respectively). A small number of SNs (<or= 3) was found to be significantly associated with false-negativity (P = 0.027).
CONCLUSIONS: SNB requires experience for successful detection and should be performed cautiously in male patients. Harvesting of more than three SNs is warranted to reduce false-negatives when diagnosing nodal metastasis.