Patients' views about parathyroid transplantation for post-thyroidectomy hypoparathyroidism

Incidence of post-surgical hypoparathyroidism (POSH) after total thyroidectomy

Post-surgical hypoparathyroidism (POSH) is a recognised complication of total thyroidectomy, leading to hypocalcaemia and its associated adverse effects. This retrospective study aimed to determine the incidence of POSH and identify perioperative predictors for its development. Data from patients who underwent total or completion thyroidectomy between January 2017 and July 2022 were retrospectively analysed. The incidence of POSH was assessed, and patients were categorised into transient or prolonged POSH at six months postoperatively. Potential predictors for POSH were investigated including gender, histological diagnosis, and preoperative thyroid function. A total of 133 adult patients were included in the study. The incidence of patients recovering from transient POSH within six months was 15%, and 5% had prolonged POSH beyond six months of surgery. Parathyroid hormone (PTH) levels normalised in 83% of prolonged POSH patients within 14-33 months, reducing the incidence of persistent POSH to 0.75%. Despite normal PTH levels, overall, 3% had persistent marginally low calcium levels (mean 2.11 mmol/L) in keeping with relative parathyroid insufficiency. Histological diagnosis of malignancy was the only significant risk factor for both transient and prolonged POSH (RR 2.95, CI 1.54 to 5.67, p = 0.001) in this cohort. Cautious capsular dissection during thyroidectomy and protection of the parathyroid glands and vascular supply produce a low incidence of POSH. Although the vast majority of patients with POSH recover after six months, hypocalcaemia may persist due to relative parathyroid insufficiency, requiring long-term calcium supplementation. Further research is needed to determine the best strategies for preventing and treating this condition.

Efficacy of parathyroid autotransplantation in endoscopic total thyroidectomy with CLND

Purpose

To evaluate the safety and efficacy of autologous parathyroid transplantation in laparoscopic total thyroidectomy combined with central lymph node dissection (CLND).

Methods

Retrospective analysis of clinical data of 152 patients admitted to the General Surgery Department of Gansu Provincial People's Hospital who underwent endoscopic total thyroidectomy combined with CLND from June 2018 to December 2021. The intraoperative parathyroid glands were divided into the orthotopic preservation group (non-transplantation group) and the immediate active autologous transplantation group (transplantation group) according to the different treatment management of parathyroid glands during operation. The levels of Ca2+ in parathyroid blood and the incidence of hypoparathyroidism were compared between the two groups before operation and 1 day, 3 day, 1 week, 1 month, 3 months and 6 months after operation.

Results

There was no significant difference in PTH between the preoperative transplantation group compared and the non-transplantation group (P>0.05); The PTH in the transplantation group was lower than that of the non-transplantation group 1 and 3 d after surgery, and the difference was statistically significant (P<0.05); No statistically significant difference in PTH between patients in the transplantation group compared with those in the non-transplantation group at 1 week postoperatively (P>0.05); PTH was significantly higher in the transplant group than in the non-transplant group at 1, 3 and 6 months after surgery, with statistically significant differences (P<0.05); there was no statistically differences (P>0.05) in serum Ca2+ between the preoperative, 1d, 3d and 1 week postoperative transplantation group and the non-transplantation group; Blood Ca2+ was significantly higher in the transplant group than in the non-transplant group at 1, 3 and 6 months after surgery, with statistically significant differences (P<0.05); The rate of temporary hypoparathyroidism in the transplantion group was higher than that in the non-transplantion group, and the rate of permanent hypoparathyroidism was lower than that in the non-transplantion group (P=0.044); There was no significant difference in the concentration of PTH in the cephalic vein of the elbow between the transplanted side and the non-transplanted side at 1 day and 3 days postoperatively (P>0.05); the concentration of PTH in cephalic vein of the elbow was significantly higher than that in non-transplanted side at 1 week, 1 month, 3 months and 6 months postoperatively (P<0.001); the number central area dissection and metastasis dissection in the transplantation group were significantly higher than those in the non-transplantation group (P<0.05).

Conclusions

Most autologous parathyroid glands, having functional parathyroid autograft, is helpful to the occurrence of hypoparathyroidism after endoscopic total thyroidectomy with CLND, and it is an effective strategy to prevent permanent hypoparathyroidism, and more thorough area dissection is beneficial to the disease prognosis.

Single inferior parathyroid autotransplantation during total thyroidectomy with bilateral central lymph node dissection for papillary thyroid carcinoma: a retrospective cohort study

BACKGROUND

Management of the inferior parathyroid gland using total thyroidectomy (TT) with central lymph node dissection (CLND) is still controversial. Therefore, we evaluated the safety and effectiveness of single inferior parathyroid autotransplantation.

METHODS

The clinical data of patients with papillary thyroid carcinoma (PTC) who underwent TT with bilateral CLND from January 2018 to December 2020 were collected. Quality of life (QoL) was assessed using the Chinese version of the EORTC QLQ-C30 and THYCA-QOL. The patients were divided into an autotransplantation group and a preservation group according to whether a single inferior parathyroid gland was transplanted. The incidence of permanent hypoparathyroidism, the number of resected central lymph nodes (CLNs), the rate of recurrence reoperation, the rate of radioactive iodine (RAI) treatment, and the QoL score were compared between the two groups.

RESULTS

A total of 296 patients were included in the study; there were 99 patients in the autotransplantation group and 197 in the preservation group. The incidence of permanent hypoparathyroidism was 3.0% (3/99) and 4.6% (9/197) in the autotransplantation and preservation groups, respectively (P = 0.532). The median number of resected CLNs was 12 (8-17) and 10 (6-14) in the autotransplantation and preservation groups, respectively (P = 0.015). No reoperations were performed for patients with CLN recurrence, and the rates of lateral lymph node (LLN) recurrence reoperation were 2.0% (2/99) and 3.6% (7/197) in the autotransplantation and preservation groups, respectively (P = 0.473). The RAI treatment rates were 12.1% (12/99) and 22.3% (44/197) in the autotransplantation and preservation groups, respectively (P = 0.034). A total of 276 questionnaires were recovered, including 84 in the autotransplantation group and 192 in the preservation group. The QoL of the two groups of patients is similar (P > 0.05).

CONCLUSION

Single inferior parathyroid autotransplantation during thyroidectomy can be used to prevent permanent hypoparathyroidism and can enable more extensive CLND.

Parathyroid Allotransplantation: A Systematic Review

Background: To date, there is no satisfactory treatment for patients with calcium and vitamin D supplementation refractive hypoparathyroidism. Parathyroid allotransplantation by design is a one-time cure through its restoration of the parathyroid function and, therefore, could be the solution. A systematic literature review is conducted in the present paper, with the aim of outlining the possibilities of parathyroid allotransplantation and to calculate its efficacy. Additionally, various transplantation characteristics are linked to success. Methods: This review is carried out according to the PRISMA statement and checklist. Relevant articles were searched for in medical databases with the most recent literature search performed on 9 December 2021. Results: In total, 24 articles involving 22 unique patient cohorts were identified with 203 transplantations performed on 148 patients. Numerous types of (exploratory) interventions were carried out with virtually no protocols that were alike: there was the use of (non-) cryopreserved parathyroid tissue combined with direct transplantation or pretreatment using in vitro techniques, such as culturing cells and macro-/microencapsulation. The variability increased further when considering immunosuppression, graft histology, and donor–recipient compatibility, but this was found to be reported in its entirety by exception. As a result of the large heterogeneity among studies, we constructed our own criterium for transplantation success. With only the studies eligible for our assessment, the pooled success rate for parathyroid allotransplantation emerged to be 46% (13/28 transplantations) with a median follow-up duration of 12 months (Q1–Q3: 8–24 months). Conclusions: Manifold possibilities have been explored around parathyroid allotransplantation but are presented as a double-edged sword due to high clinical diverseness, low expertise in carrying out the procedure, and unsatisfactory study quality. Transplantations carried out with permanent immunosuppression seem to be the most promising, but, in its current state, little could be said about the treatment efficacy with a high quality of evidence. Of foremost importance in pursuing the answer whether parathyroid allotransplantation is a suitable treatment for hypoparathyroidism, a standardized definition of transplantation success must be established with a high-quality trial.

Parathyroid allotransplantation for the treatment of permanent hypoparathyroidism: A systematic review

BACKGROUND

Hypoparathyroidism is the most common complication of bilateral operations in the central neck. No formal guidelines exist for the management of permanent hypoparathyroidism. Current treatment involving medical supplementation increases resource utilization and patient morbidity while decreasing quality of life. Parathyroid allotransplant (PA) offers a promising therapy; however, the optimal technique and role of immunosuppression (IS) in PA remain unclear.

METHODS

We performed a systematic search of the Embase, MEDLINE, and Cochrane Library databases to identify studies investigating PA for treatment of hypoparathyroidism.

RESULTS

A total of 24 studies including 186 individual allograft transplants in 146 patients were identified. Pooled graft survival for allotransplants in transplant-naïve vs prior transplant recipients was 29.9% and 80%, respectively.

CONCLUSIONS

PA using normocellular, fresh parathyroid donor tissue that is ABO-compatible, with induction and, at minimum, short-term maintenance IS presents a potentially safe and effective therapeutic option for permanent hypoparathyroidism in patients tolerating IS.

MANAGEMENT OF ENDOCRINE DISEASE: Postsurgical hypoparathyroidism: current treatments and future prospects for parathyroid allotransplantation

BACKGROUND

Permanent postsurgical hypoparathyroidism (POSH) is a major complication of anterior neck surgery in general and of thyroid surgery in particular. Depending on diagnostic criteria, up to 10% of patients undergoing bilateral thyroid surgery develop POSH. This leads to a multitude of symptoms that decrease the quality of life and burden the healthcare provision through complex needs for medication and treatment of specific complications, such as seizures and laryngospasm.

METHODS

Narrative review of current medical treatments for POSH and of the experience accumulated with parathyroid allotransplantation.

RESULTS

In most patients, POSH is controlled with regular use of calcium supplements and active vitamin D analogues but a significant proportion of patients continue to experience severe symptoms requiring repeated emergency admissions. Replacement therapy with synthetic PTH compounds (PTH1-34, Natpara® and PTH1-84, teriparatide, Forsteo®) has been assessed in multicentre trials, but the use of this medication is restricted by costs and concerns related to the risk of development of osteosarcoma. Based on recent case reports of successful allotransplantation of parathyroid tissue between siblings, there is renewed interest in this technique. Data on selection of donors, parathyroid cell preparation before allotransplantation, site and timing of transplantation, need for immunosuppression and long-term outcomes are reviewed.

CONCLUSION

A prospective trial to assess the efficacy of parathyroid allotransplantation in patients with severely symptomatic protracted post-surgical hypoparathyroidism is warranted.

Superior parathyroid blood supply safety in thyroid cancer surgery: A randomized controlled trial

BACKGROUND

To evaluate the clinical value of a technique protecting blood supply to the superior parathyroid during surgery for thyroid cancer.

MATERIALS AND METHODS

The observation group comprised 113 patients admitted to our hospital during the period from January 1, 2016 to December 31, 2016, who were diagnosed with thyroid cancer and treated by surgery using a technique protecting blood supply to the superior parathyroid. The control group comprised 113 patients diagnosed with thyroid cancer who were treated by surgery using the conventional technique. Postoperative parathyroid function damage and blood calcium levels were assessed in both groups.

RESULTS

The incidences of hypocalcemia and low parathyroid hormone in the observation and control groups were 10.6% and 31.9%, and 14.2% and 35.4%, respectively. The relative risk (RR) of the control group was increased (RR = 3.009 for control; RR = 2.493 for observation). Univariate logistic regression analysis showed that postoperative temporary hypoparathyroidism was associated with lymph node metastasis, use of the above protective technique, and tumor size [(odds ratio, OR = 1.936, 95%CI 1.029-3.643; P = 0.041), (OR = 0.301, 95%CI 0.156-0.579; P = 0.001) and (OR = 2.022, 95%CI 1.089-3.756; P = 0.026), respectively]. Postoperative temporary hypoparathyroidism was also associated with lymph node dissection (Bilateral vs. No, P = 0.003) and T classification (T3 vs. T1, P = 0.034). Multivariate logistic regression analysis showed that, after including significant independent variables of univariate logistic regression analysis (e.g., lymph node metastasis, lymph node resection, protective technique, tumor size, and T classification), the protective technique was a factor supporting reduced incidence of postoperative temporary hypoparathyroidism (OR = 0.325, 95% CI 0.163-0.648; P = 0.001).

CONCLUSION

Application of a technique protecting blood supply to the superior parathyroid during thyroid cancer surgery effectively reduced the incidence of postoperative temporary hypoparathyroidism. However, because of the imbalance in lymph node dissection between the two groups, confounding factors could not be completely eliminated, and matched pair analysis is needed to eliminate these factors.