Postoperative Thyroid-stimulating Hormone Research Articles

Prognostic Implications of Maintaining the Target Thyroid-Stimulating Hormone Status Based on the 2015 American Thyroid Association Guidelines in Patients with Low-Risk Papillary Thyroid Carcinoma after Lobectomy: A 5-Year Landmark Analysis

Background: The 2015 American Thyroid Association guidelines recommend the maintenance of serum thyroid stimulating hormone (TSH) levels ≤2 mIU/L in patients with low-risk papillary thyroid carcinoma (PTC) who underwent lobectomy; however, the evidence is insufficient. We investigated the association between maintaining the TSH status at ≤2 mIU/L and tumor recurrence in patients with low-risk PTC who underwent lobectomy through a 5-year landmark analysis. Methods: Between 2010 and 2016, 662 patients with low-risk PTC were included. The postoperative TSH status was determined using the ‘TSH > 2 ratio’, which was calculated using the TSH test results during the 5-year follow-up. The optimal cutoff value of ‘TSH > 2 ratio’ for tumor recurrence was determined using a receiver operating characteristic curve analysis. Recurrence-free survival (RFS) was compared between the groups using Kaplan–Meier and Cox proportional hazard regression analyses. Results: Patients with ‘TSH > 2 ratio’ > 0.1833 (n = 498) had a worse RFS outcome compared to patients with ‘TSH > 2 ratio’ ≤ 0.1833 (n = 164; p < 0.001). ‘TSH > 2 ratio’ > 0.1833 was a significant risk factor for tumor recurrence after the 5-year landmark (hazard ratio: 4.795, 95% confidence interval: 2.102–10.937, p < 0.001). Conclusions: Maintaining TSH levels ≤ 2 mIU/L below a certain percentage among the total TSH tests during the 5-year follow-up period has a negative impact on tumor recurrence.

Comparison of the effectiveness of ultrasound-guided radiofrequency ablation and conventional open thyroidectomy in the treatment of benign thyroid nodules.

To compare the effectiveness of ultrasound (US)-guided radiofrequency ablation (RFA) and conventional open thyroidectomy (OT) in the treatment of benign thyroid nodules (BTN). Medical records of 103 patients with BTN undergoing surgical treatment at The Affiliated Jiangning Hospital of Nanjing Medical University from March 2019 to March 2022 were retrospectively analyzed. Records show that 53 patients underwent US-guided RFA (observation group) and 50 patients underwent conventional OT (control group). Perioperative indicators (operation duration, intraoperative blood loss, postoperative hospital stay, incision length, and VAS score 12h and 24h after surgery), complications, thyroid function, and nodule recurrence in both groups were compared and analyzed. Perioperative indicators of patients in the observation group were better, and the visual analogue scale (VAS) scores at 12 and 24 hours after the surgery were lower than those of the control group (p<0.05). The incidence of complications in the observation group was significantly lower than that in the control group (p<0.05). There was no statistically significant difference in the preoperative levels of thyroid-stimulating hormone (TSH), serum free thyroxine (FT4) and serum free triiodothyronine (FT3) between the two groups (p>0.05). The postoperative TSH levels in the observation group increased compared to the preoperative levels and were higher than those in the control group, while FT4 and FT3 levels decreased after surgery and were lower than those in the control group (p<0.05). Compared to conventional open thyroidectomy, US-guided RFA is associated with less trauma, faster recovery, fewer complications, and less impact on thyroid function in the treatment of patients with BTN.

Retracting the thyroid matters: Who develops asymptomatic transient thyrotoxicosis after parathyroidectomy

BackgroundHyperthyroidism after parathyroidectomy is not a well-understood complication. We sought to determine the incidence and risk factors of hyperthyroidism after parathyroidectomy. Materials and methodsThis is a prospective study of 91 patients undergoing parathyroidectomy. Pre- and post-operative thyroid-stimulating hormone(TSH) and free thyroxine(T4) levels at two-week follow-ups were collected. Bivariate analyses were conducted to compare demographics, laboratory results, and intraoperative findings between patients with normal and suppressed post-parathyroidectomy TSH. ResultsTwenty-two(24.2 ​%) patients had suppressed TSH after parathyroidectomy and 2(2.2 ​%) reported symptoms of hyperthyroidism. All hyperthyroidism resolved within 6 weeks. No patients required medical treatment. Compared to the normal TSH group, the suppressed TSH group had significantly more bilateral explorations(91.0 ​% vs. 58.0 ​%, p ​= ​0.006), and superior parathyroid resections(95.5 ​% vs. 65.2 ​%, p ​= ​0.006). ConclusionTransient hyperthyroidism is common following parathyroidectomy, which is likely associated with intraoperative thyroid manipulation. Gentle retraction of thyroid glands in parathyroidectomy is warranted, especially during superior parathyroid gland resection.

Assessment for bone health in patients with differentiated thyroid carcinoma after postoperative thyroid-stimulating hormone suppression therapy: a new fracture risk assessment algorithm.

The fracture risk assessment tool (FRAX) is used to assess the 10-year risk of major site and hip fractures; however, whether this tool can be applied to patients receiving levothyroxine-based thyroid-stimulating hormone (TSH) suppressive therapy for postoperative differentiated thyroid cancer (DTC) patients is yet to be clarified. A total of 64 patients with DTC following thyroidectomy and oral levothyroxine for TSH suppression therapy and 30 gender- and age-matched controls were collected. The fracture risk was compared between the affected groups with different TSH levels. FRAX was used to calculate the fracture risk with and without bone mineral density (BMD). The TSH level was converted to an age-weighted score to estimate the fracture risk of postoperatively differentiated thyroid cancer patients. The sensitivity, specificity, and area under the AUC curve of the traditional FRAX and the new algorithm for osteoporosis diagnosis were compared. The dual-energy X-ray bone mineral density measurement T score was used as the gold standard to diagnose osteoporosis. There were 24 patients in the T ≥ -1-2.5 group, 23 in the -2.5 < T < -1 group, and 17 in the T ≤ -2.5 group. The T score of BMD in the disease group was significantly lower than that in the control group (p < 0.05). The risk of MOF and hip fracture without a T score were significantly different under various TSH levels (p < 0.05). The area under the curve (AUC) of FRAX without BMD for predicting major osteoporotic fractures (PMOF) and major hip fractures (PHF) was 0.694 and 0.683, respectively. The cutoff values were 2.15% and 0.25%, respectively. The AUC of FRAX with BMD for PMOF and PHF was 0.976 and 0.989, respectively, and the cutoff values were 4.15% and 1.1%, respectively. The AUC of FRAX without BMD for PMOF and PHF was 0.708 and 0.72, respectively, and the cutoff values were 5.5% and 1.55%, respectively. FRAX is suitable for postoperative DTC patients after TSH suppressive therapy. In the absence of BMD, TSH weighted by age can improve the specificity of FRAX in the diagnosis of osteoporosis in this population.

Lymph node ratio independently associated with postoperative thyroglobulin levels in papillary thyroid cancer

ObjectivesTo investigate the impact of the lymph node ratio (LNR) on postoperative thyroglobulin (Tg) levels in patients with papillary thyroid carcinoma (PTC). Patients and MethodsThis was a retrospective, cohort study. The association between clinicopathological variables and postoperative unstimulated Tg (uTg) levels, preablative-stimulated Tg (sTg) levels, and postablative unstimulated Tg levels was analysed. ResultsA total of 300 patients with PTC were identified. Multivariate logistic analysis showed that M classification (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.62–3.34), and postoperative thyroid-stimulating hormone levels (OR, 1.01; 95% CI, 1.01–1.02) were independently associated with postoperative uTg levels. One hundred and sixteen patients underwent radioactive iodine (RAI) therapy. Multivariate analysis showed that LNR in the central neck (OR, 1.24; 95% CI, 1.02–1.51), LNR in the lateral neck (OR, 1.73; 95% CI, 1.09–2.77), RAI dose (OR, 1.43; 95% CI, 1.21–1.69), and M classification (OR, 1.79; 95% CI, 1.22–2.61) were independently associated with preablative sTg levels. Tumour size (OR, 1.01; 95% CI, 1.00–1.01), LNR in the central neck (OR, 1.28; 95% CI, 1.08–1.51), LNR in the lateral neck (OR, 1.66; 95% CI, 1.10–2.49), RAI dose (OR, 1.54; 95% CI, 1.34–1.79), and M classification (OR, 1.56; 95% CI, 1.12–2.19) were also independently associated with postablative uTg levels. ConclusionLNR was independently associated with postoperative Tg levels in patients with PTC. Patients with high LNR were more likely to have incomplete biochemical responses after surgery.

Development of a predictive score for post-hemithyroidectomy hypothyroidism using skeletal muscle index, remnant thyroid index, and thyroid-stimulating hormone levels: a retrospective cohort study.

Hypothyroidism is a major complication of hemithyroidectomy. Low remnant thyroid volume and high serum thyroid-stimulating hormone (TSH) levels are suggested as risk factors for post-hemithyroidectomy hypothyroidism. Reduced skeletal muscle mass is associated with a variety of postoperative complications. However, its impact on post-hemithyroidectomy hypothyroidism has not yet been studied. This study aimed to evaluate the association between skeletal muscle mass and the onset of post-hemithyroidectomy hypothyroidism and develop a predictive score using skeletal muscle mass in combination with previously reported risk factors. This study retrospectively analyzed 226 consecutive patients who underwent hemithyroidectomy at Shinshu University Hospital between January 2011 and December 2020. The skeletal muscle area at the fourth thoracic vertebral level and maximal remnant thyroid area were quantified using preoperative computed tomography and standardized by dividing them by the square of the patient's height, designated as the skeletal muscle index (SMI) and remnant thyroid volume index (RTI). Subclinical hypothyroidism was defined as a postoperative elevated serum TSH level (>5 µU/mL) with a normal free thyroxine (FT4) level (≥0.9 ng/dL), overt hypothyroidism as a postoperative increase in serum TSH level (>5 µU/mL) and a decrease in serum FT4 level (<0.9 ng/dL), and symptomatic hypothyroidism as an elevated serum TSH level (>5 µU/mL) with hypothyroidism-related symptoms. Logistic regression analysis was used to determine the factors associated with the onset of hypothyroidism. Patients with euthyroid status had significantly higher SMI and RTI than those who developed post-hemithyroidectomy hypothyroidism (SMI, euthyroid: 12.0±2.4 vs. subclinical hypothyroid: 10.2±1.7, P<0.001, euthyroid vs. overt or symptomatic hypothyroid: 10.1±1.7, P<0.001, RTI, euthyroid: 1.19±0.41 vs. subclinical hypothyroid: 0.92±0.35, P<0.001, euthyroid vs. overt or symptomatic hypothyroid: 0.84±0.30, P<0.001). Multivariable analysis demonstrated that low SMI, low RTI [hazard ratio (HR): 3.35, P<0.001], and preoperative high serum TSH levels (HR: 2.54, P=0.003) were independent predictive factors for hypothyroidism. Patients who had low SMI, low RTI, and preoperative high serum TSH levels were more likely to develop hypothyroidism (68.8%) than those with either one (25.3%), two (47.8%), or none (15.2%) of these three factors. Preoperative evaluation of the SMI, RTI, and serum TSH levels may be useful in predicting the development of post-hemithyroidectomy hypothyroidism.

Exploring endocrinological pitfalls in pituitary surgery in the elderly

BackgroundEndoscopic transsphenoidal surgery (ETSS) is performed more frequently in elderly patients. We investigated endocrinological pitfalls in pituitary surgery in the elderly by a comparative study focusing only on elderly patients. MethodsNinety-nine elderly patients aged 65 years and over with non-functioning pituitary adenoma (NFPA) who underwent ETSS were retrospectively examined and classified into the early (aged 65–74 years) and late (aged 75 years and over) elderly groups. The baseline characteristics and anterior pituitary function were compared between the groups. ResultsSeventy patients were assigned to the early elderly group and 29 to the late elderly group. Thyroid-stimulating hormone (TSH) response in preoperative and postoperative thyrotropin-releasing hormone (TRH) tests revealed a significant difference between the groups. Preoperative and postoperative TSH responses were significantly correlated in both groups. Residual analysis of the correlation between preoperative free triiodothyronine (T3) secretion quantity and preoperative TSH response in both groups, which was significant, indicated that preoperative TSH response was significantly normal when preoperative free T3 secretion quantity was normal in the early elderly group, but preoperative free T3 secretion quantity was significantly lower regardless of preoperative TSH response in the late elderly group. ConculsionsThe present study suggested that preoperative and postoperative TSH secretory capacity was presumed to be normal when preoperative free T3 levels were normal in the early elderly patients with NFPA. On the other hand, TSH secretory capacity in the late elderly patients could only be assessed by the TRH test, which should be taken into account.

The Incidence of Hypothyroidism Following Hemithyroidectomy in a Tertiary Academic Center in Saudi Arabia

Background Hemithyroidectomy is a common procedure used to treat various benign and malignant conditions. It is often associated with complications, of which hypothyroidism is an underappreciated sequel. We sought to comprehend the rate and associated risk factors for developing hypothyroidism following hemithyroidectomy at King Abdulaziz University Hospital (KAUH). Methods In this retrospective study, we reviewed the medical records of all patients who had hemithyroidectomies for benign and malignant conditions between January 2008 and August 2022. Patients were analyzed for age, gender, body mass index (BMI), comorbidities, family history of thyroid disease, thyroid antibodies, and pre- and postoperative thyroid-stimulating hormone (TSH). Pre- and postoperative TSH levels were compared using the Wilcoxon signed-rank test. Results From 153 cases, 39 patients met the inclusion criteria; 31 (79.5%) were females. Seventeen (43.59%) patients developed biochemical hypothyroidism within two years following hemithyroidectomy; the majority (64.71%) of those with hypothyroidism developed it within the first six months. There was a significant increase in TSH levels following surgery (p< 0.001). Conclusion The overall incidence of hypothyroidism within two years of hemithyroidectomy is 43.59%; among those who developed hypothyroidism, the majority (64.71%) did so within the first six months. Thus, we strongly recommend continuous monitoring of TSH levels in the first six months, as it may aid in the decision to begin treatment before symptoms develop.

Evaluation of Afamin Level after Bariatric Surgery in Patient with Obesity.

The aim of this study is to evaluate afamin levels after weight loss in obese patients who underwent laparoscopic sleeve gastrectomy (LSG) and to investigate the relationship between them. In addition, after bariatric surgery, thyroid stimulating hormone (TSH), thyroxine (T4), low-density lipoprotein (LDL), very low-density protein (VLDL), total cholesterol, triglyceride (TG), high-density lipoprotein (HDL), insulin, and hemoglobin A1c (HgbA1c) levels were evaluated. Preoperative and postoperative 6th month venous blood samples were obtained from 43 patients included in this study. The preoperative and postoperative 6th month body mass index (BMI), TG, total cholesterol, VLDL, HDL, insulin, HgbA1c, TSH, T4, and afamin levels of the patients who underwent bariatric surgery with obesity were compared. Serum afamin levels of patients decreased at 6 months postoperatively; however, it was not statistically significant. We observed a statistically significant decrease in patients' BMI, HDL, VLDL, TG, total cholesterol, TSH, T4, HgbA1c, and insulin values (p < 0.05). There were significant increases in HDL and T4 values. The change in LDL value was statistically insignificant. Recent studies have shown that there may be a cause-effect relationship between afamin and obesity. In our study, we observed a decrease in serum afamin levels after weight loss following bariatric surgery. In addition, we think that afamin may be used as a potential marker of metabolic syndrome in the future and may lead to improvements in the medical treatment of obesity.

Predictive factors for hypothyroidy after hemithyroidectomy.

Background: Hemithyroidectomy is one of the most common procedures performed. It is used to treat patients with benign unilateral nodules. Hemithyroidectomy results in fewer risks of hypothyroidism and the need for thyroid hormone replacement therapy. The present study was designed to identify potential clinicopathologic risk factors associated with the onset of biochemical hypothyroidism. Methods: We conducted a retrospective review of all patients who underwent hemithyroidectomy between 2004 and 2019. Hypothyroidism was defined as a serum thyrotropin level greater than 5 mIU/L. The patients were analyzed for age, sex, preoperative and postoperative thyroid stimulating hormone (TSH), state, side, and volume of the remaining lobe, and histologic diagnosis. Results: Hypothyroidism was diagnosed in 30.8% of 214 patients. This complication appeared in the first year in 83.3% of the cases. A preoperative TSH level greater than 1.32 mIU/l, a remaining volume of the lobe less than 3 ml, and the presence of thyroiditis were associated with a significant increase in the risk of developing hypothyroidism (p<0.01). There were no significant differences in age, sex, state, and side of the remaining lobe. The mean thyroxine dose was 57 ± 26 micrograms. Conclusions: The risk of hypothyroidism after hemithyroidectomy should be assessed prior to surgery. Close monitoring is recommended in patients at high risk of developing this complication. However, all patients who undergo hemithyroidectomy should be monitored at least for the first year.

Total Thyroidectomy and Subsequent Weight Gain in Pediatric Populations.

To evaluate weight gain in children post-thyroidectomy and identify predictors. Charts from patients at a tertiary health care facility who underwent total thyroidectomy from 2014 to 2020 were reviewed for Body Mass Index z-scores (BMIz) at the time of thyroidectomy and at 1 and 2-year post-operation intervals. Patient demographic information, comorbidities, pre- and postoperative thyroid stimulating hormone, and postoperative free T4 levels were also extracted. Patients with other known endocrine abnormalities, chronic kidney disease, or without sufficient follow-up were excluded. A total of 56 patients (ages 3-17 years old) met the inclusion criteria (n=17 Graves' disease; n=39 presumed cancer). Over the first year, average BMIz significantly increased in patients with Graves' disease (∆BMIz=0.45 ± 0.77, p=0.03), Hispanic ethnicity (∆BMIz=0.43 ± 0.68, p=0.004), Medicaid/no insurance coverage (∆BMIz=0.33 ± 0.74, p=0.038), age <13 years at thyroidectomy (∆BMIz=0.35 ± 0.68, p=0.016), and persistent postoperative hypothyroidism (∆BMIz=0.41 ± 0.41, p=0.012). These changes remained significant after the second year. Age at thyroidectomy correlated negatively with ∆BMIz only after the first year (r=-0.40, p=0.002). Regression analysis, controlling for Graves' status, persistent postoperative hypothyroidism, and insurance coverage, identified age at thyroidectomy as a significant predictor of ∆BMIz after the first year (b=-0.06, p=0.004) and Hispanic ethnicity as a significant predictor after the second year (b=0.60, p=0.003). A small increase in BMIz post-thyroidectomy was observed across several patient subgroups. Younger age at thyroidectomy and Hispanic ethnicity were associated with increased BMIz in the first 2 years post-thyroidectomy. Level 4 - Historically controlled cohort Laryngoscope, 133:1518-1523, 2023.

Predictive factors for hypothyroidy after hemithyroidectomy.

Background: Hemithyroidectomy is one of the most common procedures performed. It is used to treat patients with benign unilateral nodules. Hemithyroidectomy results in fewer risks of hypothyroidism and the need for thyroid hormone replacement therapy. The present study was designed to identify potential clinicopathologic risk factors associated with the onset of biochemical hypothyroidism. Methods: We conducted a retrospective review of all patients who underwent hemithyroidectomy between 2004 and 2019. Hypothyroidism was defined as a serum thyrotropin level greater than 5 mIU/L. The patients were analyzed for age, sex, preoperative and postoperative thyroid stimulating hormone (TSH), state, side, and volume of the remaining lobe, and histologic diagnosis. Results: Hypothyroidism was diagnosed in 30.8% of 214 patients. This complication appeared in the first year in 83.3% of the cases. A preoperative TSH level greater than 1.32 mIU/l, a remaining volume of the lobe less than 3 ml, and the presence of thyroiditis were associated with a significant increase in the risk of developing hypothyroidism (p<0.01). There were no significant differences in age, sex, state, and side of the remaining lobe. The mean thyroxine dose was 57 ± 26 micrograms. Conclusions: The risk of hypothyroidism after hemithyroidectomy should be assessed prior to surgery. Close monitoring is recommended in patients at high risk of developing this complication. However, all patients who undergo hemithyroidectomy should be monitored at least for the first year.

Thyroid hormone replacement following lobectomy: Long-term institutional analysis 15 years after surgery

BackgroundThe decision to pursue lobectomy versus total thyroidectomy is highly individualized. The rate of thyroid hormone replacement therapy after lobectomy varies considerably (15%–48%) and studies are limited by short-term follow-up. We sought to assess long-term thyroid hormone replacement therapy-requirement for lobectomy. MethodsPatients undergoing lobectomy from January 2005 to July 2010 at an academic institution were reviewed. Demographic, laboratory, pathology, and thyroid hormone replacement therapy use were compared. ResultsIn total, 235 patients were included. The rate of thyroid hormone replacement therapy after lobectomy was 46.8% (110/235). The majority were female (84.7%), with a mean age of 52 ± 1 years, 97% with benign pathology, and the median duration of follow-up was 7.2 years. Among the 110 thyroid hormone replacement therapy, the mean postoperative thyroid stimulating hormone level 9.08 ± 0.96m IU/L and the time to thyroid hormone replacement therapy-initiation was 621 days; 24% started therapy ≥2 years after surgery. There was no difference in age, sex, or malignancy. Hashimoto thyroiditis was diagnosed in 21.8% patients who underwent thyroid hormone replacement therapy versus 8.0% of those without thyroid hormone replacement therapy (odds ratio 3.2; 95% confidence interval, 1.43–6.79; P < .001). On multivariate analysis, only Hashimoto thyroiditis was independently associated with thyroid hormone replacement therapy use (odds ratio 2.88; 95% confidence interval, 1.3–6.6; P = .012). ConclusionWith long-term follow-up, nearly 50% of patients who underwent lobectomy for benign disease required thyroid hormone replacement therapy and nearly one-quarter of these patients not starting until ≥2 years after surgery. Therefore, patients who undergo thyroid lobectomy should be counseled appropriately and thyroid function followed for a minimum of 2 years.

Effects of TSH suppressive therapy on bone mineral density (BMD) and bone turnover markers (BTMs) in patients with differentiated thyroid cancer in Northeast China: a prospective controlled cohort study.

This study aimed to evaluate the effects of thyroid-stimulating hormone (TSH) suppressive therapy on bone mineral density (BMD) and bone turnover markers (BTMs) in differentiated thyroid cancer (DTC) patients after postoperative 1-2 years in Northeast China. Five male, sixteen premenopausal, and eight postmenopausal female DTC patients receiving TSH suppressive therapy after thyroidectomy were enrolled. Patients were matched with healthy controls in a ratio of 1:2. All participants completed postoperative 1-year follow-up, and postmenopausal women completed 2-year follow-up. We measured BMD of the lumbar spine (LS), femoral neck (FN), and total hip (TH) using dual-energy X-ray absorptiometry (DXA). Bone formation marker P1NP and bone resorption marker β-CTX were also evaluated. Fracture risks were assessed by FRAX. There was no difference in BMD and BTMs between DTC patients and controls in the male group at 1-year follow-up. In the premenopausal women, the baseline P1NP was significantly lower in DTC patients than in the controls. The LS-BMD, FN-BMD, and TH-BMD in DTC patients were all higher than those in controls at 1-year follow-up. The difference in FN-BMD was not significant after adjusting for baseline P1NP. In the postmenopausal women, no differences in BMD and BTMs were observed between DTC patients and controls at the 1-year and 2-year follow-up. Our study indicated that postoperative 1-year TSH suppressive therapy did not show detrimental effects on BMD and BTMs in men, premenopausal, and postmenopausal DTC patients. The 2-year postoperative TSH suppressive therapy did not lead to additional loss of bone mass in postmenopausal DTC patients.

Magnetic resonance imaging characteristics predict pituitary function in non-functional pituitary macro-adenoma undergoing trans-sphenoidal surgery

IntroductionMaintaining the pituitary function after surgery is highly important. The aim of this study was to investigate the relationship between preoperative magnetic resonance imaging (MRI) characteristics and pituitary function after surgery of non-functional pituitary macroadenoma.MethodsThis retrospective study was performed between 2016 and 2018. Preoperative and postoperative MRI imaging data were retrieved from electronic registration system. The relationship between preoperative MRI characteristics and postoperative pituitary function as well as reconstruction of pituitary gland was investigated using regression models.ResultsComplete data were available for 44 patients. Before surgery, invisible normal tissue was observed in 23 patients (53.5%). Suprasellar extension and cavernous sinus invasion were seen in 36 patients (each one 49.1%). There was a significant reverse relationship between preoperative tumor size and postoperative thyroid stimulating hormone (TSH) (odds ratio (OR): − 0.99 (− 0.18, − 0.003), p = 0.04). In addition, we found a significant positive correlation between prolactin level after surgery and tumor size before surgery, (OR: 5.29 (1.65, 8.92), p = 0006). Moreover, postoperative panhypopituitarism was observed in 25% of patients with complete morphologic reconstitution of pituitary tissue. While the rate was 50% in patients with no or partial morphologic reconstruction of pituitary tissue.ConclusionPreoperative MRI characteristics predict TSH and prolactin level after operation. Furthermore, the adenoma size and volume prior to surgery are the main determinants of normal morphologic reconstruction of pituitary gland.

Is Maintaining Thyroid-Stimulating Hormone Effective in Patients Undergoing Thyroid Lobectomy for Low-Risk Differentiated Thyroid Cancer? A Systematic Review and Meta-Analysis.

Simple SummaryIn order to reduce the recurrence rate after surgical treatment of differentiated thyroid cancer (DTC), suppression of thyroid-stimulating hormone (TSH) or maintenance of a certain level after surgery are important. However, the effectiveness of TSH maintenance in the mid to lower reference range (0.5–2 mU/L) in patients undergoing thyroid lobectomy for low-risk DTC is uncertain. In this systematic review and meta-analysis, we compared and analyzed the recurrence rate according to whether TSH maintenance was performed in patients who underwent thyroid lobectomy for low-risk DTC. There was no difference in the recurrence rate with or without TSH control. Therefore, the recommendation to maintain TSH to reduce the recurrence rate after thyroid lobectomy is still controversial.There is no clear evidence that post-operative maintenance of thyroid-stimulating hormone (TSH) in the mid to lower reference range (0.5–2 mU/L) improves prognosis in patients undergoing thyroid lobectomy for low-risk differentiated thyroid cancer (DTC). The purpose of this systematic review and meta-analysis was to compare and analyze the recurrence rate according to whether the serum TSH level was maintained below 2 mU/L in patients who underwent thyroid lobectomy for low-risk DTC. Clinical data and outcomes were collected from MEDLINE, Embase, and the Cochrane Database of Systematic Reviews. The inclusion criteria were related studies on TSH maintenance or serum TSH concentration after surgery for DTC. Seven observational studies with a total of 3974 patients were included in this study. In the patients who received TSH maintenance less than 2 mU/L, the recurrence rate during the follow-up period was 2.3%. A subgroup analysis of five studies showed that the odds ratio for recurrence in patients who received TSH maintenance was 1.45 (p-value = 0.45) compared to patients who did not receive TSH maintenance. In conclusion, the evidence for the effectiveness of post-operative TSH maintenance less than 2 mU/L in patients undergoing thyroid lobectomy for low-risk DTC is insufficient.

Is thyroid hormone supplementation avoidable for patients with low‐risk papillary thyroid cancer after thyroid lobectomy? A two‐center observational study

Changing insights regarding the extent of surgery for low-risk papillary thyroid cancer (PTC) stir up discussions on the benefits and harms of thyroid lobectomy versus total thyroidectomy. The chance of needing postoperative thyroid hormone supplementation after thyroid lobectomy is still unclear. The purpose of this retrospective two-center study was to identify the incidence and risk factors of postoperative thyroid-stimulating hormone (TSH) elevation (>2.0 μIU/ml) after thyroid lobectomy for low-risk PTC. Medical records of 201 consecutive patients with low-risk PTC from two tertiary centers who underwent thyroid lobectomy between 2015 and 2019 were retrospectively reviewed. Postoperative thyroid function tests were measured regularly and patients were prescribed levothyroxine if the TSH level was higher than 2.0 μIU/ml. Multivariable regression models were used to evaluate potential risk factors associated with postoperative TSH elevation after thyroid lobectomy. At 6 weeks postoperatively, 85% had TSH level of >2 μIU/ml; this increased to 88% by 3-6 months. Receiver operating characteristic analysis identified preoperative TSH cut-off (>1.7 μIU/ml) to predict postoperative TSH elevation. Multivariate analysis revealed that only a high preoperative TSH level (>1.7 μIU/ml) was an independent risk factor for a postoperative TSH level of >2 μIU/ml (odds ratio = 7.71; p < .001). Nearly 90% of the patients who underwent thyroid lobectomy for low-risk PTC had a postoperative TSH level of >2 μIU/ml, necessitating thyroid hormone supplementation in accordance with current guidelines. This finding highlights that preoperative patient counseling should also focus on raising awareness about postoperative thyroid hormone supplementation for low-risk PTC patients seeking thyroid lobectomy.

Effect of sleeve gastrectomy on thyroid-stimulating hormone levels in morbidly obese patients with normal thyroid function.

There are many studies, which demonstrate that morbid obesity is associated with an increase in Thyroid Stimulating Hormone (TSH) levels. However, the effect of Laparoscopic Sleeve Gastrectomy (LSG) procedure on postoperative TSH levels is not clear. This study aims to evaluate the effect of weight loss after LSG procedure on TSH levels in euthyroid patients with morbid obesity. 159 Euthyroid patients who applied for an LSG procedure (93.7% female, with a mean age of 34.18±10.01 years, BMI 43.2±6.82 kg/m2) were retrospectively analyzed for the study. The parameters used in the analysis were their serum free T3 levels (fT3), free T4 levels (fT4), and TSH levels preoperatively and at 6 months after surgery. The postoperative correlation between TSH and BMI (Body Mass Index), % EWL (Percent Excess Weight Loss), and % TWL (Total Weight Loss) levels were evaluated. Mean BMI change from 43.2±6.82 kg/m2 to 30.48±5.63 kg/m2 (p<0.001), 6 months after LSG, was associated with a mean reduction in the TSH from 2.27±1.09 µU/dL to 1.61±0.99 µU/dL; p<0.001). Serum fT3 levels (3.23±0.42 ng/dL at baseline and 3.21±0.48 ng/dL at 6 months after surgery; p=0.409) remained steady. Serum fT4 levels (1.21±0.18 µU/dL at baseline and 1.43±0.20 µU/dL at 6 months after LSG; p<0.001) increased. Change in TSH was significantly correlated with change in BMI at 6 months after surgery (r=0.200, p=0.015). However, the decrease in TSH following LSG procedure did not correlate with % EWL (r=-0.114, p=0.159) and % TWL (r=-0.100, p=0.209). After the LSG procedure, there was a significant decrease in TSH levels and a significant increase in fT4 levels, but no change was seen in fT3 levels. While this decrease in TSH levels showed a positive correlation with BMI, no statistically significant correlation was found with % EWL and % TWL.

Frequency of Thyroid Hormone Replacement After Lobectomy for Differentiated Thyroid Cancer

ObjectiveTo determine the frequency of levothyroxine (LT4) supplementation after therapeutic lobectomy for low-risk differentiated thyroid cancer (DTC). MethodsThis retrospective cohort study enrolled adult patients with low-risk DTC confirmed using surgical pathology who underwent therapeutic lobectomy at a single institution from January 2016 through May 2020. The outcome measures were postoperative serum thyroid-stimulating hormone (TSH) levels and the initiation of LT4. The predictors of a postoperative TSH level of >2 mU/L and initiation of LT4 were evaluated using Cox proportional hazards models. ResultsPostoperative TSH levels were available for 115 patients (91%), of whom 97 (84%) had TSH levels >2 mU/L after thyroid lobectomy. Over a median follow-up of 2.6 years, a postoperative TSH level of >2 mU/L was associated with older age (median 52 vs 37 years; P = .01), higher preoperative TSH level (1.7 vs 0.85 mU/L; P < .001), and primary tumor size of <1 cm (38% vs 11%, P = .03). Multivariate analysis revealed that only preoperative TSH level was an independent predictor of a postoperative TSH level of >2 mU/L (hazard ratio [HR] 1.53, P = .003). Among patients with a postoperative TSH level of >2 mU/L, 66 (68%) were started on LT4 at a median of 74 days (interquartile range 41-126) after lobectomy, with 51 (77%) undergoing at least 1 subsequent dose adjustment to maintain compliance with current guidelines. ConclusionMore than 80% of the patients who underwent therapeutic lobectomy for DTC developed TSH levels that were elevated beyond the recommended range, and most of these patients were prescribed LT4 soon after the surgery.

Weight change in patients with differentiated thyroid carcinoma after total thyroidectomy versus lobectomy.

Thyroid hormone is an important hormone in maintaining metabolism and homeostasis in the body. There exists a common perception among patients that thyroid surgery will cause weight gain. Prevention of any undesired weight gain could be important for the maintenance of well-being in most patients. Our study compares changes in body mass index (BMI) and weight after total thyroidectomy or lobectomy in thyroid cancer patients. A total of 967 patients with differentiated thyroid carcinoma were enrolled in the study, from March 2011 to July 2016 at Chung-Ang University Hospital. Exclusion criteria were less than lobectomy, modified radical neck dissection, recurred operation, and combined operation for other causes. Primary endpoints were change in body weight and BMI at 2 years after surgery. A subgroup analysis was performed for patients with significant weight change. There were no differences between both groups in BMI after 2 years of thyroid operation. Thyroid stimulating hormone (TSH) levels were not significantly different. Fifteen percent of patients showed significant change in body weight after 2 years of operation. The subgroup analysis of these patients showed no significant differences in gender, age, or extent of operation between those who had gained weight compared to those who had lost weight. There were also no differences in postoperative TSH levels, levothyroxine supplementation, or radioactive iodine treatment. There was a minimal postoperative increase in mean BMI over the years in patients undergoing thyroidectomy for differentiated thyroid cancer. However, weight change did not differ in those undergoing thyroid lobectomy or total thyroidectomy.