Page 109 - Fluorescence-guided cancer surgery

Intraoperative guidance in parathyroid surgery 107
Combining the two groups showed that in 16/25 patients the preoperative 99mTc-sestamibi-SPECT/CT scan indicated an adenoma. In 15 out of these 16 patients, the detected adenoma was NIR uorescent, leading to a positive predictive value of 94%. The only patient who had a 99mTc-sestamibi-SPECT/ CT positive lesion, that appeared non- uorescent, was a patient who su ered from parathyroid carcinoma.
DISCUSSION
Despite the fact that surgical resection of parathyroid adenomas is a commonly performed and overall successful surgical procedure, intraoperative detection of an adenoma can be challenging. Moreover, the anatomical site where parathyroid adenomas are located contains many vital structures like arteries, veins, and nerves. When preoperative localization fails, and extended surgical neck exploration is needed, the risk of iatrogenic damage to these structures and associated complications increase16. Therefore, intraoperative optical guidance in parathyroid surgery using exogenous contrast agents could assist in a faster and more accurate identi cation of parathyroid adenomas, without causing iatrogenic injury to surrounding vital structures.
Previously our research group showed feasibility of intraoperative identi cation of parathyroid adenomas using NIR uorescence imaging and low-dose MB in humans14. In that clinical trial, MB was administered after surgical exposure of the adenoma. The current study con rmed the results of the previous described study, showing the possibility to intraoperatively identify parathyroid adenomas using MB and its correlation with preoperative a 99mTc-sestamibi-SPECT/CT scan. Combining the two groups showed that 16 out of these 25 patients had a 99mTc-sestamibi-SPECT/CT scan indicating an adenoma. In 15 out of these 16 patients, the detected adenoma was NIR uorescent, leading to a positive predictive value of 94% for a NIR uorescent adenoma after a positive 99mTc-sestamibi-SPECT/CT scan. These ndings suggest that all patients with a positive 99mTc-sestamibi-SPECT/CT scan should receive MB for the improved identi cation of parathyroid adenomas.
In the current study, 2 parathyroid adenomas did not uoresce. The histopathological analysis of these 2 adenomas were comparable with the NIR uorescent positive adenomas, so the reason for non- uorescence remains unclear.