Pitfalls of minimally invasive parathyroidectomy for the treatment of primary hyperparathyroidism.

OBJECTIVE: To analyze the risk factors associated with failure of minimally invasive parathyroidectomy (MIP) in patients with primary hyperparathyroidism (PHPT). MATERIALS AND METHODS: A retrospective analysis was performed using a prospectively collected database of patients diagnosed with primary hyperparathyroidism who underwent MIP between December 2006 and November 2025. Demographic, intraoperative, and postoperative variables were analyzed. Logistic regression analysis was performed to identify risk factors associated with failures in MIP, which included conversion to bilateral neck exploration (BNE), disease persistence (DP), and disease recurrence (DR). RESULTS: A total of 497 patients underwent MIP; 427 (85.9%) were women, with a mean age of 59.8 years (range: 22-93 years). Fifty-nine patients (11.9%) required conversion to BNE. A gland weight greater than 300 mg and discordant preoperative imaging studies were independently associated with conversion to BNE in both univariable and multivariable analyses. Postoperatively, 13 patients (2.6%) presented with DP, and a significant association was found between this failure and age over 70 years (p < 0.05). Recurrent disease occurred in only 3 patients (0.6%). Obesity, a gland weight greater than 300 mg and discordant imaging studies showed an association with DR in the univariable analysis; however, these findings should be interpreted cautiously given the low number of recurrence events. CONCLUSION: Patients with over 70 years, those without preoperative matching studies, and/or those with gland weight exceeding 300 mg should be informed about the increased risk of failure of MIP. Appropriate patient selection is essential to minimize the risk of MIP failure.