An Alternative and Up-To-Date Recommendation for a Proper Site for Parathyroid Transplantation: The Omentum

Various sites have been used for parathyroid allotransplant, such as injection into the forearm, sternocleidomastoid, or deltoid muscles. However, transplant efficiency in these regions varies according to the results reported in the literature and also obtained from our previous studies. Using the omentum "as a natural incubator" for composite tissue-derived cell transplants to increase transplant success is possible.

To examine the efficiency of transplant sites for parathyroid allotransplant, we compared clinical cases from the literature and our experience with 23 cases. The omental transplant process is performed under general anesthesia by laparoscopic intervention. The abdominal cavity is visualized with an endocamera from a 5-mm trocar. With the help of a flexible catheter from another 5-mm trocar, microencapsulated or naked parathyroid cells are deposited on the omentum in approximately 30 mL of isotonic saline. The trocar sites are then sutured, and the surgery is terminated. Recipients were followed for 6 months with examination of biochemical parameters (parathormone, calcium, and phosphorus levels), medication use, and clinical scoring.

In the 23 patients who received parathyroid allotransplants over the omentum, 7 recipients did not exhibit any changes according to the scoring system criteria. However, on average, serum calcium and phosphorus levels remained within the healthy reference range. In addition, use of oral medications among patients decreased, indicating successful transplant survival. These results were consistent with a significant decrease in hypocalcemia symptoms among patients.

In the 23 patients, the success rate was 69.5% for the first 6-month period after transplant. Recent developments and large cohorts are needed to demonstrate the higher efficacy of parathyroid allotransplant over the omentum.