Point mutations of the human parathyroid calcium receptor gene are not responsible for non-suppressible renal hyperparathyroidism

Point mutations of the human parathyroid calcium receptor gene are not responsible for non-suppressible renal hyperparathyroidism. The calcium-dependent secretion of parathyroid hormone (PTH) is mediated through an extracellular G protein-coupled calcium receptor (CaR). Inactivating point mutations of this receptor have been found in familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism. These diseases feature a decreased calcium sensitivity of the parathyroid glands, resulting in a rightward shift of the Ca2+-PTH relationship. Severe, non-suppressible renal hyperparathyroidism (rHPT) is often characterized by similar setpoint shifts to the right. Thus, point mutations of the CaR gene could contribute to non-suppressible rHPT. We examined genomic DNA of hyperplastic or mainly nodular tissues of 39 parathyroids from 25 rHPT-patients with resistance to calcitriol therapy. Amplification of the six exons of the CaR gene was followed by single-strand conformation polymorphism (SSCP) analysis. DNA sequencing was performed where band shifts were observed. No point mutations in the coding sequence of the CaR gene were detected using the PCR-SSCP strategy. Point mutations in the coding regions of the CaR gene probably play no role in the evolution of renal HPT and are not responsible for the calcitriol resistance of PTH secretion

Correlation of perioperative biochemical variables with single adenoma weight in patients with primary hyperparathyroidism

Background!#!Single parathyroid adenoma is the main cause of primary hyperparathyroidism (PHPT), with surgery remaining the gold standard for its treatment. The ability to preoperatively predict the parathyroid adenoma size and could facilitate the decision about the extent of surgical exploration. It is reasonable to hypothesize that the perioperative levels of PHPT-related variables (i.e. calcium, parathormone, phosphate) may predict the adenoma weight or/and demonstrate whether the adenoma is successfully removed or not. Aim of this study is to explore the relationship between perioperative biochemical values and adenoma weight. Secondarily, we investigated the relationship between adenoma weight and uni-/bilateral neck exploration.!##!Methods!#!Retrospective study of all patients undergone surgery for primary hyperparathyroidism due to single adenoma in a tertiary university hospital in Germany during a 6-year period. Following variables were analyzed: preoperative serum calcium, phosphorus and parathormone, intraoperative parathormone before and after adenoma excision, intraoperative PTH decrease, postoperative serum calcium and parathormone (PTH!##!Results!#!A total of 339 patients were included in the study. The median age of the patients was 60 years (range 21-90) and 77% were females. The median adenoma weight was 1 g (range 0.1-11). Adenoma weight correlated strong with maximum adenoma diameter (r = 0.72, p < 0.05), moderate with preoperative parathormone (r = 0.44) and parathormone decrease (r = 0.27), whereas there was no correlation with the intraoperative PTH decrease (r = 0.02). There was also a borderline (moderate to weak) correlation with pre- and postoperative calcium levels (r = 0.21 and r = 0.23 respectively) and a negative borderline correlation with phosphorus (r = - 0.21). Patients who required bilateral neck exploration, had significantly lighter adenomas (median weight 0.8 g vs 1.1 g, p = 0.005).!##!Conclusions!#!We conclude that preoperative PTH levels may only serve as an approximate guide to adenoma weight, as direct preoperative prediction is not possible. Serum calcium levels, PTH and calcium decrease correlate only weak with adenoma weight. Patients who require bilateral neck exploration, have significantly (20-25%) lighter adenomas

Current Practice of Surgery for Benign Goitre—An Analysis of the Prospective DGAV StuDoQ|Thyroid Registry

Background: To evaluate the current indications, resection strategies and short-term outcomes of surgery for benign goitre in a country with endemic goitre. Methods: Data of patients who underwent surgery for benign goitre were retrieved from the prospective StuDoQ/Thyroid registry and retrospectively analysed regarding the patient’s demographics, indications for surgery, surgical procedures, histology, and perioperative outcomes. Results: In a 15-month period, 12,888 patients from 83 departments underwent thyroid resections for benign conditions. Main indications for surgery were exclusion of malignancy (68%), compression symptoms (20.7%) and hyperthyroidism (9.7%). Preoperative fine needle aspiration cytology was performed in only 12.2% of patients with the indication “exclusion of malignancy”. Thyroidectomy (49.8%) or hemithyroidectomy (36.9%) were performed in 86.7% of patients. Minimally invasive or alternative surgical techniques were applied in only 2.2%. Intraoperative neuromonitoring was used in 98.4% of procedures, in 97.5% of patients at least one parathyroid gland was visualized, and in 15.3% of patients parathyroid tissue was autografted, respectively. The rates of unilateral and bilateral transient recurrent nerve palsy were 3.6% and 0.07% of nerves at risk, the rate of transitory hypoparathyroidism was 15.3%. The rates of postoperative bleeding and wound infections requiring reoperation were 1.4% and 0.07%, respectively. Conclusions: The indication “exclusion of malignancy” is made too liberally, and there is a strong attitude to perform complete thyroid resections. Postoperative hypoparathyroidism is the major complication after surgery for benign thyroid disease, thus requiring more awareness

Current practice of surgery for benign goitre—an analysis of the prospective DGAV StuDoQ|Thyroid registry

Background: To evaluate the current indications, resection strategies and short-term outcomes of surgery for benign goitre in a country with endemic goitre. Methods: Data of patients who underwent surgery for benign goitre were retrieved from the prospective StuDoQ/Thyroid registry and retrospectively analysed regarding the patient’s demographics, indications for surgery, surgical procedures, histology, and perioperative outcomes. Results: In a 15-month period, 12,888 patients from 83 departments underwent thyroid resections for benign conditions. Main indications for surgery were exclusion of malignancy (68%), compression symptoms (20.7%) and hyperthyroidism (9.7%). Preoperative fine needle aspiration cytology was performed in only 12.2% of patients with the indication "exclusion of malignancy". Thyroidectomy (49.8%) or hemithyroidectomy (36.9%) were performed in 86.7% of patients. Minimally invasive or alternative surgical techniques were applied in only 2.2%. Intraoperative neuromonitoring was used in 98.4% of procedures, in 97.5% of patients at least one parathyroid gland was visualized, and in 15.3% of patients parathyroid tissue was autografted, respectively. The rates of unilateral and bilateral transient recurrent nerve palsy were 3.6% and 0.07% of nerves at risk, the rate of transitory hypoparathyroidism was 15.3%. The rates of postoperative bleeding and wound infections requiring reoperation were 1.4% and 0.07%, respectively. Conclusions: The indication "exclusion of malignancy" is made too liberally, and there is a strong attitude to perform complete thyroid resections. Postoperative hypoparathyroidism is the major complication after surgery for benign thyroid disease, thus requiring more awareness

Short-Term Outcomes of Surgery for Graves’ Disease in Germany

Background: Surgical treatment of Graves’ disease (GD) has a potentially increased incidence of postoperative hypoparathyroidism, recurrent laryngeal nerve palsy (RLNP) and bleeding. The aim of this study was to evaluate the current extent of surgery for the treatment of GD and its safety as a short-term outcome. Methods: Patients who underwent thyroid resection for GD were identified from the prospective StuDoQ/Thyroid registry. Patient data were retrospectively analyzed regarding demographics, surgical procedures and perioperative outcomes. Statistics were performed with Student’s t-test or Fisher’s exact test and multivariate Cox regression analysis. The level of statistical significance was set at p < 0.05. Results: A total of 1808 patients with GD with a median age of 44 (range 14–85) years were enrolled in a 25-month period by 78 departments, of which 35.7% (n = 645) had an endocrine orbitopathy and 0.1% (n = 6) had thyrotoxic crisis. Conventional open surgery was used in 98.6% of cases and minimally invasive or remote-access approaches were used in 1.4%. Total thyroidectomy was performed in 93.4% of cases (n = 1688). Intraoperative neuromonitoring (IONM) was used in 98.9% (n = 1789) of procedures. In 98.3% (n = 1777) at least one parathyroid gland was visualized and in 20.7% (n = 375) parathyroids were autografted. The rates of unilateral and bilateral transient RLNP were 3.9% (n = 134/3429 nerves at risk) and 0.1% (n = 4/3429 NAR). The rates of transient RLNP tended to be higher when intermittent IONM was used compared to continuous IONM (4.1% vs. 3.4%, p < 0.059). The rate of transient postoperative hypoparathyroidism was overall 29% (n = 525/1808). Multivariate analysis revealed fewer than 300 thyroid resections and fewer than 15 thyroid resections for GD per year, male sex, BMI > 30, autotransplantation of parathyroid glands and previous bilateral thyroid surgery as independent risk factors for postoperative temporary hypoparathyroidism. Reoperations for bleeding (1.3%) were rare. Conclusion: Total thyroidectomy with IONM is safe and currently the most common surgical therapy for GD in Germany. Postoperative hypoparathyroidism is the major complication which should be focused on

Preoperative calcitonin testing improves the diagnosis of medullary thyroid carcinoma in female and male patients

Weber T, Powlawski A, Vorlander C, et al. Preoperative calcitonin testing improves the diagnosis of medullary thyroid carcinoma in female and male patients. European Journal of Endocrinology. 2021: EJE-21-1015.R1.Calcitonin (Ctn) measurement in patients with thyroid disease could potentially increase the detection rates of medullary thyroid carcinoma (MTC) but remains a controversial issue. The aim of this study was to evaluate routine preoperative Ctn measurements.; METHODS: All patients with thyroid surgery documented in the prospective StuDoQ|Thyroid registry between 03/2017 and 09/2020 were included. Cutoff levels for Ctn were determined with ROC analyses to assess the preoperative diagnosis of MTC in subgroups for females and males.; FINDINGS: In 29.590 of 39.679 patients (75%) participating in the registry, routine preoperative Ctn testing was performed. In 357 patients (227 females, 130 males) histopathology confirmed MTC with a mean tumor size of 14.7 mm (± 12.43). Biochemical cure was achieved in 71.4% of the patients. Ctn levels between 11 and 20 pg/ml were seen in 2.6% of the patients, and only 0.7% of the patients had Ctn levels above 21 pg/ml. Cutoff levels for the diagnosis of MTC were 7.9 pg/ml for females and 15 pg/ml for males (p 7.9 pg/ml and males >15 pg/ml without any other extrathyroidal sources for an elevated Ctn should be monitored. Thyroid surgery should be considered if Ctn levels are increasing, or ultrasound detects suspicious thyroid lesions