Adrenal Vein Sampling: Does the Location of the Non-adrenal Venous Sample Matter?

PURPOSE: Adrenal vein sampling (AVS) is used to lateralise and differentiate unilateral from bilateral aldosterone production in primary aldosteronism. The adrenal venous samples are standardised to a peripheral or low inferior vena cava (IVC) sample and compared. It is unknown whether the location of the non-adrenal sample affects the results. This study compares AVS results standardised to the low IVC and right external iliac vein (REIV). METHODS: Patients who underwent AVS between March 2021 and May 2023 were included. All procedures were undertaken by a single operator (AA). Demographic data and AVS results were collected from patients' electronic records. Catheterisation success and lateralisation were assessed using both low IVC and REIV samples. Equivalence test was used to compare the cortisol and aldosterone levels. RESULTS: Eighty-one patients, (M: F = 38:43), aged between 29 and 74 were included. Bilateral successful adrenal vein cannulation was achieved in 79/81 (97.5%) cases. The mean cortisol levels from the REIV were statistically equivalent although there was a small and not biologically significant difference from the low IVC (respective geometric means 183 nmol/l vs. 185 nmol/l, p = 0.015). This small difference in cortisol may be due to accessory adrenal venous drainage into the IVC. The aldosterone and aldosterone/cortisol ratios were statistically equivalent. There was no discordance in selectivity or lateralisation when the IVC or REIV measurements were used. CONCLUSION: The IVC and REIV samples may be used interchangeably during AVS.

Correlation of Preoperative Imaging Findings and Parathyroidectomy Outcomes Support NICE 2019 Guidance.

CONTEXT: Preoperative localization studies are standard practice in patients undergoing parathyroidectomy for primary hyperparathyroidism (pHPT). The most common modalities are neck ultrasound (US) and sestamibi scanning. However, the nature of pHPT is changing, with imaging increasingly yielding negative results. Numerous studies suggest unlocalized disease is associated with poor outcomes, calling into question whether such patients are best treated conservatively. OBJECTIVE: This study aims to correlate parathyroidectomy outcomes with preoperative imaging in a single, high-volume institution. METHODS: Data from a prospectively maintained departmental database of operations performed from 2017 to 2019 were analyzed. All patients undergoing first-time surgery for sporadic pHPT were included. Data collected included patient demographics, preoperative imaging, surgical strategy, and postoperative outcomes. RESULTS: A total of 609 consecutive parathyroidectomies were included, with a median age of 59 years (range 20-87 years). The all-comer cure rate was 97.5%; this was 97.9% in dual localized patients (those with positive US and sestamibi), compared to 95.8% in the dual unlocalized group (those with negative US and sestamibi) (P = 0.33). Unilateral neck exploration was the chosen approach in 59.9% of patients with double-positive imaging and 5.7% of patients with double-negative imaging (otherwise, bilateral parathyroid visualization was performed). There was no significant difference in postoperative complications between patients undergoing unilateral or bilateral neck exploration. CONCLUSIONS: Patients with negative preoperative imaging who undergo parathyroidectomy are cured in almost 96% of cases, compared to 98% when the disease is localized. This difference does not reach statistical or clinical significance. These findings therefore support current recommendations that all patients with pHPT who are likely to benefit from operative intervention should be considered for parathyroidectomy, irrespective of preoperative imaging findings.

Parathyroid surgery: an evidence-based volume-outcomes analysis : European Society of Endocrine Surgeons (ESES) positional statement.

BACKGROUND: The interest in correlation between hospital and surgeon practice volume and postoperative outcomes has grown considerably over the last decades; it has been suggested that surgery is likely to be associated with higher cure rates, lower morbidity and more favourable results in cost-effectiveness when performed in a high-volume setting. The aim of this paper is to undertake an evidence-based literature review of the relationship between surgical volume and clinical outcomes in parathyroidectomy for primary hyperparathyroidism. We used accepted quality markers to identify the relationship between volume and outcome with a view to defining a reproducible minimal surgical volume-related standard of care in parathyroid surgery. METHODS: A peer review literature analysis of volume and outcomes in parathyroid surgery was carried out and assessed from an evidence-based perspective. Results were discussed at the 2019 Conference of the European Society of Endocrine Surgeons devoted to "Volumes, Outcomes and Quality Standards in Endocrine Surgery". RESULTS: Literature reports no prospective randomised studies; thus, a low level of evidence may be achieved. CONCLUSIONS: Parathyroid surgery is at increased risk of failures, morbidity and need for reoperations and cost when performed in low-volume settings; thus, it should be concentrated in dedicated settings, with adequate annual volume and expertise. Acceptable results may be achieved moving parathyroid surgery cases away from low-volume settings (< 15 parathyroidectomies/year). Challenging procedures (primary hyperparathyroidism without unequivocal preoperative localization, hereditary variants, paediatric patients, reoperations) should be confined to high-volume settings (> 40 parathyroidectomies/year).

Autofluorescence in Parathyroidectomy: Signal Intensity Correlates with Serum Calcium and Parathyroid Hormone but Routine Clinical Use is Not Justified.

BACKGROUND: The inability to identify the pathological gland at surgery results in failure to cure hyperparathyroidism in 2-5%. The poorly understood characteristic of parathyroid tissue to manifest autofluorescence (AF) under near-infrared (NIR) light has been promoted as an intraoperative adjunct in parathyroid surgery. This study sought to explore potential clinical correlates for AF and assess the clinical utility of AF in parathyroid surgery. METHODS: Consecutive patients undergoing parathyroid surgery for primary and renal disease were included. NIR imaging was used intraoperatively and the degree of AF of parathyroid glands graded by the operating surgeon. Variables assessed for correlation with AF were: pre-operative serum calcium and PTH, SestaMIBI positivity, gland weight and histological composition. RESULTS: Ninety-six patients underwent parathyroidectomy over an 8-month period: 49 bilateral explorations, 41 unilateral and 6 focussed lateral approaches: 284 potentially 'visualisable' glands in total. Two hundred and fifty-seven glands (90.5%) were visualised with NIR. Correlation was found between the degree of fluorescence and pre-operative serum calcium and PTH, but not between gland weight and SestaMIBI positivity. In those with renal hyperparathyroidism, a predominance of oxyphil cells correlated with increased AF. CONCLUSION: Autofluorescence intensity correlates with serum calcium, PTH and gland composition. Further refinements would be required for this information to be of value in a clinical setting. Improvements allowing NIR to visualise the additional 9.5% of parathyroids and overcome the variation in signal intensity due to depth of access are required for the routine adoption of this technology. At present, its routine use in a clinical setting cannot be justified.

Undiagnosed Primary Hyperparathyroidism and Recurrent Miscarriage: The First Prospective Pilot Study.

BACKGROUND: Primary hyperparathyroidism (pHPT) in pregnancy is reported to be associated with significant maternal and foetal complications and an up to threefold increase in the risk of miscarriage. However, the true incidence of pHPT in pregnancy, complete and miscarried, is unknown and there are no data on the prevalence of undiagnosed pHPT in recurrent miscarriage (RM) (≥3 consecutive miscarriages under 24-week gestation). This is the first prospective study aiming to establish the prevalence of undiagnosed pHPT in RM. METHODS: Following UK National ethics committee approval, women who had experienced 3 or more consecutive miscarriages were recruited from a nationwide RM clinic. Serum corrected calcium, phosphate, PTH and vitamin D were evaluated. Patients with raised serum calcium and/or PTH were recalled for confirmatory tests. Power calculations suggested that a minimum of 272 patients were required to demonstrate a clinically significant incidence of pHPT. RESULTS: Three hundred women were recruited, median age 35 years (range 19-42). Eleven patients had incomplete data, leaving 289 patients suitable for analysis; 50/289 patients (17%) with abnormal tests were recalled. The prevalence of vitamin D deficiency (<25 nmol/l) and insufficiency (25-75 nmol/l) was 8.7 and 67.8%, respectively. One patient was diagnosed with pHPT (0.34%) and underwent successful parathyroidectomy. CONCLUSIONS: The prevalence of undiagnosed pHPT (0.34%) in RM in this study appears to be many times greater than the 0.05% expected in this age group. The findings of this pilot study merit follow-up with a larger-scale study. Routine serum calcium estimation is not currently undertaken in RM and should be considered.

A role for TET2 in parathyroid carcinoma.

Primary hyperparathyroidism (pHPT) is rarely caused by parathyroid carcinoma (PC, <1-5% of pHPT cases). The TET proteins oxidize the epigenetic mark 5-methylcytosine to 5-hydroxymethylcytosine (5hmC) and inactivation by mutation or epigenetic deregulation of TET1 and TET2 play important roles in various cancers. Recently, we found that 5hmC was severely reduced in all of the analyzed PCs and with deranged expression of TET1 for the majority of PCs. Here, we have examined the expression of the TET2 protein in 15 5hmC-negative PCs from patients who had local invasion or metastases. Cell growth and cell migratory roles for TET2 as well as epigenetic deregulated expression were addressed. Immunohistochemistry revealed very low/undetectable expression of TET2 in all PCs and verified for two PCs that were available for western blotting analysis. Knockdown of TET2 in the parathyroid cell line sHPT-1 resulted in increased cell growth and increased cell migration. DNA sequencing of TET2 in PCs revealed two common variants and no obvious inactivating mutations. Quantitative bisulfite pyrosequencing analysis of the TET2 promoter CpG island revealed higher CpG methylation level in the PCs compared to that in normal tissues and treatment of a PC primary cell culture with the DNA methylation inhibitor 5-aza-2'-deoxycytidine caused increased expression of the methylated TET2 gene. Hence, the data suggest that deregulated expression of TET2 by DNA hypermethylation may contribute to the aberrantly low level of 5hmC in PCs and further that TET2 plays a cell growth and cell migratory regulatory role and may constitute a parathyroid tumor suppressor gene.

5-Hydroxymethylcytosine discriminates between parathyroid adenoma and carcinoma.

BACKGROUND: Primary hyperparathyroidism is characterized by enlarged parathyroid glands due to an adenoma (80-85 %) or multiglandular disease (~15 %) causing hypersecretion of parathyroid hormone (PTH) and generally hypercalcemia. Parathyroid cancer is rare (<1-5 %). The epigenetic mark 5-hydroxymethylcytosine (5hmC) is reduced in various cancers, and this may involve reduced expression of the ten-eleven translocation 1 (TET1) enzyme. Here, we have performed novel experiments to determine the 5hmC level and TET1 protein expression in 43 parathyroid adenomas (PAs) and 17 parathyroid carcinomas (PCs) from patients who had local invasion or metastases and to address a potential growth regulatory role of TET1. RESULTS: The global 5hmC level was determined by a semi-quantitative DNA immune-dot blot assay in a smaller number of tumors. The global 5hmC level was reduced in nine PCs and 15 PAs compared to four normal tissue samples (p < 0.05), and it was most severely reduced in the PCs. By immunohistochemistry, all 17 PCs stained negatively for 5hmC and TET1 showed negative or variably heterogeneous staining for the majority. All 43 PAs displayed positive 5hmC staining, and a similar aberrant staining pattern of 5hmC and TET1 was seen in about half of the PAs. Western blotting analysis of two PCs and nine PAs showed variable TET1 protein expression levels. A significantly higher tumor weight was associated to PAs displaying a more severe aberrant staining pattern of 5hmC and TET1. Overexpression of TET1 in a colony forming assay inhibited parathyroid tumor cell growth. CONCLUSIONS: 5hmC can discriminate between PAs and PCs. Whether 5hmC represents a novel marker for malignancy warrants further analysis in additional parathyroid tumor cohorts. The results support a growth regulatory role of TET1 in parathyroid tissue.

Hereditary hyperparathyroidism--a consensus report of the European Society of Endocrine Surgeons (ESES).

BACKGROUND: Hereditary hyperparathyroidism has been reported to occur in 5-10 % of cases of primary hyperparathyroidism in the context of multiple endocrine neoplasia (MEN) types 1, 2A and 4; hyperparathyroidism-jaw tumour (HPT-JT); familial isolated hyperparathyroidism (FIHPT); familial hypocalciuric hypercalcaemia (FHH); neonatal severe hyperparathyroidism (NSHPT) and autosomal dominant moderate hyperparathyroidism (ADMH). This paper aims to review the controversies in the main genetic, clinical and pathological features and surgical management of hereditary hyperparathyroidism. METHODS: A peer review literature analysis on hereditary hyperparathyroidism was carried out and analyzed in an evidence-based perspective. Results were discussed at the 2015 Workshop of the European Society of Endocrine Surgeons devoted to hyperparathyroidism due to multiple gland disease. RESULTS: Literature reports scarcity of prospective randomized studies; thus, a low level of evidence may be achieved. CONCLUSIONS: Hereditary hyperparathyroidism typically presents at an earlier age than the sporadic variants. Gene penetrance and expressivity varies. Parathyroid multiple gland involvement is common, but in some variants, it may occur metachronously often with long disease-free intervals, simulating a single-gland involvement. Bilateral neck exploration with subtotal parathyroidectomy or total parathyroidectomy + autotransplantation should be performed, especially in MEN 1, in order to decrease the persistent and recurrent hyperparathyroidism rates; in some variants (MEN 2A, HPT-JT), limited parathyroidectomy can achieve long-term normocalcemia. In FHH, surgery is contraindicated; in NSHPT, urgent total parathyroidectomy is required. In FIHPT, MEN 4 and ADMH, a tailored case-specific approach is recommended.

Lithium-associated hyperparathyroidism: surgical strategies in the era of minimally invasive parathyroidectomy.

BACKGROUND: Lithium remains an effective treatment of bipolar affective disorder. The long-term use of lithium is associated with an alteration in parathyroid function that may culminate in hyperparathyroidism. The long-term effects of lithium use are variable due to its complex effects on calcium homeostasis and bone metabolism, and as a consequence the indications for surgery remain poorly defined. The optimal surgical strategy for lithium-associated hyperparathyroidism in the era of minimally invasive surgery is also the subject of debate. The aim of the present study was to evaluate the variable findings of lithium-associated parathyroid disease. METHODS: A retrospective review was performed of patients undergoing parathyroid surgery presenting with lithium-associated hyperparathyroidism from July 1999 until July 2009 at the university hospital La Timone, Marseille, and from October 2005 to July 2009 at Hammersmith Hospital, Imperial College, London. Fifteen patients underwent surgery for lithium-associated hyperparathyroidism. Clinical data including patient demographics, duration of lithium use, clinical manifestations of hyperparathyroidism, indications for surgery, and biochemical parameters preoperatively and postoperatively were reviewed. Preoperative imaging, the surgical procedure performed, operative findings, and histopathology were also analyzed. RESULTS: All 15 patients had preoperative imaging: sestamibi scanning showed that 10 patients had localized single-gland disease, 1 had multiple hot spots, and 4 had a negative scan. Ultrasonography demonstrated a single abnormal gland in 8 patients and multiple enlarged glands in 1 patient; the test was negative in 6. As a consequence of concordant preoperative imaging a minimally invasive approach (endoscopic or a focused lateral approach) was adopted in 3 patients. Focused surgery demonstrated an enlarged hyperplastic gland in 3 cases and resulted in normocalcemia in the immediate postoperative period. However, one patient has a serum calcium at the upper limit of normal and elevated parathyroid hormone (PTH) levels, suggestive of possible recurrence of disease at 15 months follow-up. One patient has permanent hypoparathyroidism. In those patients who had open procedures, final histology showed hyperplastic multiglandular disease in 10 patients (83.3%) of patients and single-gland disease in 2 patients (16.7%). None of these patients show evidence of recurrence at follow-up. CONCLUSIONS: Lithium hyperparathyroidism is predominantly a multiglandular disease characterized by asymmetrical hyperplasia that is frequently associated with misleading or discordant localization studies. Bilateral neck exploration is therefore recommended in order to minimize the risk of disease recurrence.

Long-term follow-up after parathyroidectomy for radiation-induced hyperparathyroidism.

BACKGROUND: External radiation is associated with a risk of hyperparathyroidism. We reviewed the outcomes after operation for radiation-induced hyperparathyroidism (R-HPT). METHODS: We conducted a retrospective review of all patients who had operative therapy for R-HPT from 1980 to 2003 in our department with a minimum of 3 years of follow-up after operative therapy. RESULT: Between 1980 and 2003, 1932 patients underwent parathyroidectomy for primary hyperparathyroidism. Thirty-seven (1.92%) patients had a history of neck irradiation. Thirty-two patients underwent a bilateral exploration (BE), and 5 patients had a focused approach (FA). Thirty-five patients presented with single gland disease, and 2 patients had multiple gland disease. In the BE group, 26 patients remained cured biochemically after a median follow-up of 10.3 years (range, 3-21 years), and 6 patients had recurrence after a median of 13.2 years (range, 7-22 years). In the FA group, all 5 patients remained cured biochemically; however, the median follow-up remained shorter (6.4 years; range, 3-8 years). CONCLUSION: In R-HPT, the incidence of multiple gland disease at the time of initial operation was comparable with sporadic HPT. In the absence of thyroid disease, an FA may be proposed for R-HPT. Metachronous pathologic glands may develop several years after successful parathyroidectomy in R-HPT. Hence, lifelong follow-up of these patients is essential.

Germline NF1 mutational spectra and loss-of-heterozygosity analyses in patients with pheochromocytoma and neurofibromatosis type 1.

BACKGROUND: Neurofibromatosis type 1 (NF1) is a pheochromocytoma-associated syndrome. Because of the low prevalence of pheochromocytoma in NF1, we ascertained subjects by pheochromocytoma that also had NF1 in the hope of describing the germline NF1 mutational spectra of NF1-related pheochromocytoma. MATERIALS AND METHODS: An international registry for NF1-pheochromocytomas was established. Mutation scanning was performed using denaturing HPLC for intragenic variation and quantitative PCR for large deletions. Loss-of-heterozygosity analysis using markers in and around NF1 was performed. RESULTS: There were 37 eligible subjects (ages 14-70 yr). Of 21 patients with corresponding tumor available, 67% showed somatic loss of the nonmutated allele at the NF1 locus vs. 0 of 12 sporadic tumors (P = 0.0002). Overall, 86% of the 37 patients had exonic or splice site mutations, 14% large deletions or duplications; 79% of the mutations are novel. The cysteine-serine rich domain (CSR) was affected in 35% but the RAS GTPase activating protein domain (RGD) in only 13%. There did not appear to be an association between any clinical features, particularly pheochromocytoma presentation and severity, and NF1 mutation genotype. CONCLUSIONS: The germline NF1 mutational spectra comprise intragenic mutations and deletions in individuals with pheochromocytoma and NF1. NF1 mutations tended to cluster in the CSR over the RAS-GAP domain, suggesting that CSR plays a more prominent role in individuals with NF1-pheochromocytoma than in NF1 individuals without this tumor. Loss-of-heterozygosity of NF1 markers in NF1-related pheochromocytoma was significantly more frequent than in sporadic pheochromocytoma, providing further molecular evidence that pheochromocytoma is a true component of NF1.

Long-term outcome following laparoscopic adrenalectomy for large solid adrenal cortex tumors.

INTRODUCTION: Laparoscopic adrenalectomy (LA) is the procedure of choice for small benign adrenal tumors. In the absence of local invasion or metastases, the preoperative diagnosis of an adrenocortical carcinoma (ACC) is difficult, often leaving size as the principal predictor of malignancy. Large tumors are resectable laparoscopically, but the long-term outcome and therefore appropriateness of LA for cortical tumors > 6 cm is not known. METHODS: We reviewed the LA experience in our institution since its introduction in June 1994. Patients who underwent LA for solid cortical tumors > or = 60 mm in diameter without preoperative or intraoperative evidence of malignancy were reviewed. Follow-up data, including clinical examination, biochemical analysis, and repeat scans, were reviewed for evidence of local or systemic recurrent disease. RESULTS: Between 1994 and 2004 a total of 462 adrenalectomies were performed, 391 of which were done laparoscopically. Among them, 19 were solid cortical tumors > or = 60 mm in diameter with no overt malignant preoperative or intraoperative characteristics: 9 nonsecreting tumors, 8 Cushing's syndrome tumors (including 2 virilizing variants), 1 virilizing tumor, and 1 aldosteronoma. The mean age of the patients was 49.9 years (range 22-77 years), and the mean tumor size was 69.0 mm (range 60-80 mm). Histology confirmed a cortical adenoma in eight patients, malignant tumors in three, and indeterminate tumors in eight. The mean follow-up was 34 months (range 4-108 months). Two patients died of systemic recurrent disease (liver metastases) at 10 and 19 months, respectively, following surgery; two other patients died 12 and 21 months, respectively following surgery owing to unrelated cardiovascular and cerebrovascular pathology. One patient underwent surgery for local recurrence 54 months after primary surgery; the remaining 14 patients are well with no clinical or radiologic evidence of recurrent disease. CONCLUSIONS: Laparoscopic adrenalectomy for large solid cortical tumors without pre- or intraoperative evidence of malignancy is not contraindicated, and it is unlikely to have a deleterious effect on long-term outcome. Each case should be considered individually. We provide an algorithm for the approach to adrenocortical tumors > or = 6 cm.

Thyroid surgery: postoperative hematoma--prevention and treatment.

BACKGROUND AND AIMS: Postoperative haematoma formation is a fortunately rare but potentially life-threatening complication of thyroid surgery. This paper aims to identify potential aetiological factors, describe surgical techniques and newer haemostatic agents that may be used to minimise the risk of haematoma formation and propose surgical strategies to deal with haematoma formation. MATERIALS AND METHODS: An extensive literature search as well as own considerable experience in a tertiary referral centre endocrine surgical unit was drawn upon to review this topic. CONCLUSIONS: Postoperative haematoma may have a multifactorial aetiology. Numerous manoeuvres and surgical haemostatic agents may be employed to minimise the risk of haematoma formation but are no substitute for meticulous haemostasis. In the event of haematoma formation, early surgical re-intervention is strongly advocated with due care given to at risk structures.

A single-institution 25-year review of true parathyroid cysts.

BACKGROUND: Parathyroid cysts (PCs) are rare, and their origin is a subject of debate. They have been described as either functional, causing hyperparathyroidism, or non-functional in eucalcaemic patients. PATIENTS AND METHODS: We have performed a 25-year departmental review of PCs. Features studied included the clinical presentation and intra-operative findings, and a histological review was performed. Cases of cystic degeneration of parathyroid adenomas and pseudocystic change were excluded. RESULTS: Over 25 years, 22,009 thyroidectomies and 2,505 parathyroidectomies were performed in our department. Amongst these, 38 non-functional PCs were documented in 37 patients. The mode of presentation included incidental findings on routine chest x-ray, compressive symptoms or an asymptomatic palpable neck mass. Aspiration was the initial treatment in 14 patients and was curative in 10 of these. Four out of 14 patients underwent surgical procedures for recurrence of the cyst that occurred 6 to 48 months after aspiration. In 27 patients, surgery was performed and all identified PCs were localized in the inferior parathyroid glands. Histologically, the cyst wall consisted in associations of lymphoid, muscular, thymic, salivary, adipose and mesenchymal tissues. CONCLUSIONS: PCs are rare but should be included within the differential diagnosis of a neck lump. True PCs are non-functional. Pathological and immunohistochemical findings are suggestive of a branchial origin. Fine-needle aspiration may be curative and is diagnostic due to the characteristic appearance of the fluid and high PTH levels on assay.

The role of a more extensive surgical approach in the initial multimodality management of papillary thyroid cancer in children.

PURPOSE: Papillary thyroid cancer (PTC) in children is rare. The optimal initial surgical treatment remains controversial, given the generally favorable overall prognosis but high rate of cervical metastasis and local recurrence. Our objective was to examine the surgical outcomes of a policy of total thyroidectomy and routine selective lymph node dissection (SLND) as the initial surgical approach to children with PTC. METHODS: This is a retrospective cohort study comprising 14 children (age, < or =17 years) with PTC referred for thyroid surgery during the past 15 years. Clinical presentation, the surgical procedure, final pathology, lymph node involvement, complications, and recurrence rates are reported. RESULTS: There were 9 females and 5 males, with an average age of 12.5 years. Seven patients (50%) had clinically apparent cervical lymphadenopathy at the time of surgical referral. All subjects underwent total thyroidectomy, and 12 (86%) had SLND. Of the 12 who underwent SLND, 10 (83%) had nodal metastases. Temporary hypocalcemia was noted in 3 of the patients (21%), and 1 patient has required ongoing intermittent calcium supplementation. All patients are alive and well at follow-up with no clinical, biochemical, or radiological evidence of local recurrence. CONCLUSIONS: Total thyroidectomy with initial SLND is an appropriate surgical approach in children with PTC. It can be done without a significantly increased risk for permanent complications and may reduce the requirement for subsequent surgical intervention for local recurrence in this young population.

Parathyroid autotransplantation during total thyroidectomy--does the number of glands transplanted affect outcome?

Parathyroid autotransplantation is a technique for ensuring the continued function of parathyroid tissue at the time of total thyroidectomy (TT). The aim of this study was to ascertain whether the number of parathyroids transplanted affects the incidence of temporary and permanent hypoparathyroidism. A retrospective cohort study included all patients undergoing a TT in a single unit between July 1998 and June 2003. The number of parathyroids transplanted, the final pathology, and the incidence of temporary and permanent hypoparathyroidism were documented. Fisher's exact test was used for statistical analysis. A total of 1196 patients underwent a TT during the 5 years studied. Of these, 306 (25.6%) had no parathyroids transplanted, 650 (54.3%), 206 (17.2%), 34 (2.8%) had 1,2, or 3 glands autotransplanted, respectively. The incidence of temporary hypoparathyroidism was 9.8% for no gland transplants, 11.9%, 15.1%, and 31.4% for 1,2,and 3 gland transplants, respectively (p < 0.05). The incidence of permanent hypoparathyroidism was 0.98%, 0.77%, 0.97%, and 0%, respectively (p = NS). The incidence of temporary hypoparathyroidism was higher when surgery was performed for Graves' disease. Temporary hypocalcemia is closely related to the number of autotransplanted parathyroids during TT. The long-term outcome is not affected by the number of parathyroids autotransplanted. A "ready selective" approach to parathyroid autotransplantation is an effective strategy for minimizing the rate of permanent hypoparathyroidism.

Safety and feasibility of thyroid lobectomy via a lateral 2.5-cm incision with a cohort comparison of the first 50 cases: evolution of a surgical approach.

BACKGROUND AND AIMS: Over 500 minimal-access parathyroidectomies (MIPs) have been performed in our unit, and, from these, a technique for thyroid resection has evolved. We present a report on the evolution of minimal-access thyroid surgery (MATS) and compare the results with those from a cohort of patients operated on prior to the use of MATS. METHODS: We reviewed the evolution towards the MATS technique. The results of the MATS procedures were compared with those from an equal number of consecutive patients undergoing conventional lobectomy prior to the use of MATS. RESULTS: Fifty patients (mean age 45.6 years) underwent MATS between March 2002 and May 2004. The mean nodule diameter was 18.5 mm. In the MATS group there was one recurrent laryngeal nerve (RLN) injury, two temporary RLN neuropraxias, which recovered, and one haematoma. The control group (mean age 47.9 years) had a mean nodule size of 22 mm. In the controls there was one temporary RLN neuropraxia, which recovered, and two haematomas-P>0.05 (Fisher's exact test) for all the complications. CONCLUSIONS: MATS has evolved from an experimental approach into a safe and feasible surgical procedure based on the same operative approach as used for MIP. It provides an alternative to open thyroid surgery in appropriately selected cases.