The accuracy of sentinel node biopsy by 99m Tc-sodium phytate in patients with pancreatic cancer

Pancreaticoduodenectomy is the only potentially curative treatment for pancreatic cancer. The identification of the first nodal drainage site (sentinel node) may improve the detection of metastatic nodes and can contribute to a less invasive surgery. We aimed to determine the accuracy of sentinel node mapping in patients with pancreatic cancer using intraoperative radiotracer injection technique. At surgical exposure, peritumoral injection of 0.4-0.5 mci/0.5 ml of 99mTc- sodium phytate was performed. After tumor resection, sentinel nodes were investigated in the most common areas using a hand-held gamma probe. Any lymph node with in vivo count twice the background was considered as sentinel node, thus, it was removed and sent for pathological assessment. Then a standard lymph node dissection was performed for all patients. Fourteen patients with cancer in the head of the pancreas were included in this study. Overall, 180 lymph nodes were harvested with a mean of 11.6±4.7 lymph nodes per patient. In eight patients, at least one sentinel node could be identified (detection rate about 64%). False negative rate of the study was 3/5 (60%). Our study revealed insufficient diagnostic accuracy and high false negative rate for sentinel lymph node mapping with 99mTc- sodium phytate in pancreatic cancer.