Tumor-induced osteomalacia: An overview.

Tumor-induced osteomalacia (TIO) is rare paraneoplastic syndrome of hypophosphatemic osteomalacia, caused by phosphaturic factors secreted by small mesenchymal origin tumors with distinct pathological features, called 'phosphaturic mesenchymal tumors'. FGF23 is the most well-characterized of the phosphaturic factors. Tumors are often small and located anywhere in the body from head to toe, which makes the localisation challenging. Functional imaging by somatostatin receptor-based PET imaging is the first line investigation, which should be followed with CT or MRI based anatomical imaging. Once localised, complete surgical excision is the treatment of choice, which brings dramatic resolution of symptoms. Medical management in the form of phosphate and active vitamin D supplements is given as a bridge to surgical management or in inoperable/non-localised patients. This review provides an overview of the epidemiology, pathophysiology, pathology, clinical features, diagnosis, and treatment of TIO, including the recent advances and directions for future research in this field.

Glucocorticoid therapy as first-line treatment in primary hypophysitis: a systematic review and individual patient data meta-analysis.

Objectives: High-dose glucocorticoids are associated with improved recovery of deficits in primary autoimmune hypophysitis (PAH), but optimal dosing, route, and duration are unclear. Design: We reviewed literature for first-line glucocorticoid treatment in PAH until December 2021 and performed an individual patient data meta-analysis to analyze clinical, hormonal, and radiological outcomes with respect to route, dose, and duration (<6.5 vs 6.5-12 vs >12 weeks) of glucocorticoid treatment according to disease severity. Results: A total of 153 PAH patients from 83 publications were included. The median age at presentation was 41 (32.5-48) years with a female preponderance (70.3%). Visual field recovery was significantly better with i.v. (91.7%) as compared to oral (54.5%) route and high dose (100%) and very high dose (90.9%) as compared to medium dose (20%) of glucocorticoids. Corticotroph axis recovery was greater in i.v. (54.8% vs 28.1% oral, P = 0.033) route and increasing glucocorticoid dose group (0% vs 38.1% vs 57.1%), attaining statistical significance (P = 0.012) with very high-dose. A longer duration of treatment (>6.5 weeks) was associated with better corticotroph and thyrotroph recovery. The need for rescue therapy was lower with i.v. route (38% vs 17.5%, P = 0.012) and with increasing glucocorticoid doses (53.3% vs 34.3% vs 17.3%, P = 0.016). In severe disease, visual field and corticotroph axis recovery were significantly higher with i.v. route and very high-dose steroids. The adverse effects of glucocorticoids were independent of dose and duration of treatment. Conclusions: Very high-dose glucocorticoids by i.v. route and cumulative longer duration (>6.5 weeks) lead to better outcomes and could be considered as first-line treatment of severe PAH cases.

Genetic spectrum of Kallmann syndrome: Single-center experience and systematic review.

OBJECTIVE: To study phenotype-genotype data of Asian-Indian Kallmann syndrome (KS) from our center and systematically review the studies analyzing multiple congenital hypogonadotropic hypogonadism (CHH) genes in KS cohorts using next-generation sequencing. DESIGN, PATIENTS, MEASUREMENT: Five hundred twenty-two KS probands (our center n = 78, published studies n = 444) were included in this systematic review. Molecular diagnosis was considered if the likely pathogenic/pathogenic variant in known CHH gene/s was reported in the appropriate allelic state. Varsome prediction tool (following American College of Medical Genetics standards) was used to analyze the variants. RESULT: For our center, the molecular diagnosis was seen in 20.5% of probands and was seen more often with severe than partial reproductive phenotype (28.3% vs. 4%, p = .0013). Our center data adds eight novel variants. The molecular diagnosis was seen in 31% as per the systematic review and analysis. It ranged from 16.6% to 72.2% at different centers. The affected genes were FGFR1 (9.8%), ANOS1 (7.5%), PROKR2 (6.1%), CHD7 (5.4%), oligogenic (2.1%), and others <1% each (FGF8, SOX10, PROK2, SEMA3A, IL17RD, and GNRHR). FGFR1 and ANOS1 were the commonly affected genes globally, whereas PROKR2 was commonest in studies from China and CHD7 from Japan, South Korea and Poland. CONCLUSION(S): This systematic review highlights that the genetic yield is 31% in KS probands, with distinct regional variations. The association of severe reproductive phenotype with the higher genetic yield needs further validation.

Gonadal dysfunction in male patients with Budd Chiari syndrome and its reversibility with treatment.

BACKGROUND AND AIMS: Budd Chiari syndrome (BCS) commonly affects adolescents and adults. With improved survival, important quality-of-life parameters such as sexual life and fertility become more relevant. This study was aimed to assess the gonadal function in male patients with BCS and the effect of treatment on gonadal function. METHODS: Thirty male patients with newly diagnosed BCS were prospectively assessed for the presence of gonadal dysfunction. Erectile function was assessed using standardized International Index of Erectile Function questionnaire (IIEF). Follicular stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), estradiol, total testosterone (TT), calculated free testosterone (cFT), calculated bioavailable testosterone (cBT), sperm count, and sperm motility were compared at baseline and at 6 months of treatment for the assessment of gonadal function. RESULTS: Sixteen (53.3%) out of 30 patients were sexually active at the time of study and 5/16 (31%) had erectile dysfunction. Hypogonadotropic hypogonadism (HH) was the most common pattern seen in 50% cases followed by hypergonadotropic hypogonadism (HyH) in 23% cases. 27% patients had eugonadism. At 6 months of treatment, 60% of patients in HH group became eugonadal as compared to only 14% in HyH group. Proportion of patients with erectile dysfunction reduced (5/16 vs 1/16) after 6 months of therapy. The improvement in sperm count and sperm motility was not significant. CONCLUSION: Gonadal dysfunction is common in male patients with BCS. HH remains the most common type of hypogonadism BCS and the type which improves significantly after treatment.

Regional genotypic variations in normosmic congenital hypogonadotropic hypogonadism: our experience and systematic review.

PURPOSE: To describe phenotype-genotype data of Asian-Indian normosmic congenital hypogonadotropic hypogonadism (nCHH) from our centre and perform a systematic review of genetic studies using next-generation sequencing (NGS) in nCHH. METHODS: Sixty-eight nCHH probands from our center, and 370 nCHH probands from published studies were included. Per-patient genetic variants were analyzed as per ACMG guidelines. Molecular diagnosis was defined as presence of a pathogenic or likely pathogenic variant in a known CHH gene following zygosity status as per known mode of genetic inheritance. RESULT: At our centre molecular diagnosis was observed in 35.3% of probands {GNRHR:16.2%, FGFR1:7.3%, KISS1R:4.4%, GNRH1:2.9%, TACR3:2.9%, CHD7:1.4%}. Molecular diagnosis was observed more often (44.7% vs 14.3%, p = 0.026) with severe than partial reproductive-phenotype. The study adds 12 novel variants and suggests GNRHR p.Thr32Ala variant may have a founder effect. In per-patient systematic review (including our cohort), the molecular diagnosis was reached in 23.2%, ranging from 3.5 to 46.7% at different centers. The affected genes were FGFR1:6.4%, GNRHR:4.3%, PROKR2:3.6%, TACR3:1.8%, CHD7:1.6%, KISS1R:1.4%, GNRH1:1.4% and others (PROK2, SOX3, SOX10, SOX11, IL17RD, IGSF10, TAC3, ANOS1, oligogenic): < 1% each. FGFR1 was the most commonly affected gene in most cohorts except Asia, whereas PROKR2 (in China and Japan) and GNRHR (in India) were the commonest. CONCLUSION: (s): The global molecular diagnosis rate was 23.2% in nCHH cohorts whereas that in our cohort was 35% with a higher rate (44.7%) in those with severe reproductive-phenotype. The most commonly affected gene in nCHH patients was FGFR1 globally while it was PROKR2 in East Asia and GNRHR in India.

GNRH1 Variants in Congenital Hypogonadotropic Hypogonadism: Single-Center Experience and Systematic Literature Review.

OBJECTIVE: As GNRH1 genotype-phenotype correlation in CHH is not well studied, we aim to describe the GNRH1 variants in our CHH cohort and present a systematic review as well as genotype-phenotype analysis of all mutation-positive cases reported in the world literature. DESIGN: This is a retrospective study of GNRH1 mutation-positive patients from a western Indian center. PRISMA guidelines-based PubMed search of the published literature of all GNRH1 mutation-positive patients was conducted. SETTING: This study was conducted in an academic medical center. PATIENT(S): This study included 2 probands from our cohort and 19 probands from the world literature. MAIN OUTCOME MEASURE(S): Demographic details, clinical presentation, biochemistry, imaging, treatment details, and genotypic data were recorded. RESULT(S): Two probands in our cohort carried two novel pathogenic biallelic GNRH1 variants (p.Glu24Leu, c.238-2A>G). Both had a severe reproductive phenotype. We report successful gonadotropin therapy and fertility in 1 proband. We included 19 probands from 12 studies after the literature review. Ten CHH probands (inclusive 2 from this study) with biallelic GNRH1 variants had severe reproductive phenotype, low gonadotropin levels, low/normal prolactin, normal pituitary imaging, and no extra-reproductive phenotype. Of seven biallelic variants reported, three were frameshift, two were splice-site, and two were missense mutations. All of them were pathogenic/likely pathogenic without oligogenicity. Of seven monoallelic GNRH1 variants reported in 11 probands, 4 had nonreproductive phenotype, 3 were benign/likely benign, and 4 were oligogenic. CONCLUSION(S): GNRH1 biallelic variants lead to severe reproductive phenotype, with low gonadotropin levels without nonreproductive features or oligogenicity. However, the role of GNRH1 monoallelic variants in CHH pathophysiology for reported variants remains questionable.

Early Pulse Glucocorticoid Therapy and Improved Hormonal Outcomes in Primary Hypophysitis.

INTRODUCTION: The role of glucocorticoids in primary autoimmune hypophysitis (PAH) has been fraught with variability in regimens, leading to inconsistent outcomes in terms of anterior pituitary (AP) hormonal recovery. Hence, we aimed to compare the clinical, hormonal, and radiological outcomes of a standardized high-dose glucocorticoid therapy group (GTG) in PAH with a matched clinical observation group (COG). METHODS: Thirty-nine retrospective patients with PAH evaluated and treated at a single center in western India from 1999 to 2019 with a median follow-up duration of 48 months were subdivided into the GTG (n = 18) and COG (n = 21) and compared for the outcomes. RESULTS: Baseline demographic, hormonal, and radiological features matched between the groups, except pituitary height, which was significantly higher in GTG. Cortisol, thyroid, and gonadal axes were affected in 25 (64%), 22 (56%), and 21 (54%) patients, respectively, and central diabetes insipidus was seen in 7 (18%) patients. Panhypophysitis (PH) was the most common radiological subtype (n = 33, 84.6%). Resolution of mass effects was similar in both groups. Overall and complete AP hormonal recovery was significantly higher in the GTG than in the COG (12/14 [85.7%) vs. 6/14 [42.8%], p = 0.02; 10/14 [71.4%] vs. 1/14 [7.7%], p = 0.0007, respectively). Proportion of cases with empty sella were significantly higher in the COG (9/20 [45%] vs 1/17 [5.9%], p = 0.001). Among PH patients in the GTG (n = 17), we found duration from symptoms onset to treatment as the predictor of recovery. CONCLUSION: In a PH subtype-predominant PAH cohort, a standardized high-dose glucocorticoid regimen resulted in higher overall and complete AP hormonal recovery than that in the COG. Initiation of glucocorticoids in the early disease course may have been contributory.

68 Ga-DOTATATE PET/CT imaging in endogenous hyperinsulinemic hypoglycemia: A tertiary endocrine centre experience.

OBJECTIVE: Literature regarding utility of 68 Ga-DOTATATE PET/CT in insulinoma localization across various subgroups [benign/malignant/multiple endocrine neoplasia-1 (MEN-1) syndrome associated] remains scarce. In this study, the performance of 68 Ga-DOTATATE PET/CT was compared with contrast-enhanced computed tomography (CECT) and 68 Ga-NODAGA-Exendin-4 PET/CT (whenever available) in an endogenous hyperinsulinemic hypoglycemia (EHH) cohort. DESIGN: Retrospective audit. PATIENTS: EHH patients [N = 36, lesions (n) = 49, final diagnosis: benign sporadic insulinoma (BSI) (N = 20), malignant insulinoma (N = 4, n = 14), MEN-1 syndrome associated insulinoma (N = 9, n = 15), Munchausen syndrome (N = 2) and drug-induced hypoglycemia (N = 1)] having both preoperative imaging modalities (CECT and 68 Ga-DOTATATE PET/CT). MEASUREMENTS: Per-lesion sensitivity (Sn) and positive predictive value (PPV) for histopathological diagnosis of insulinoma. RESULTS: Sn and PPV of 68 Ga-DOTATATE PET/CT were 67.3% and 89.2%; 55% and 100%; 85.7% and 100%; and 66.7% and 77% for overall EHH, BSI, malignant, and MEN-1 syndrome associated insulinoma cohorts respectively. Despite having comparatively lower sensitivity in BSI cohort, 68 Ga-DOTATATE PET/CT localized a pancreatic tail lesion missed by other modalities. 68 Ga-DOTATATE PET/CT had comparatively higher sensitivity in malignant insulinoma than BSI cohort. 68 Ga-DOTATATE PET/CT also paved the way for successful response to 177 Lu-based peptide receptor radionuclide therapy (PRRT). In MEN-1 cases, lower PPV as compared with BSI was due to uptake in non-insulinoma pancreatic neuroendocrine tumours (Pan-NET). CONCLUSIONS: 68 Ga-DOTATATE PET/CT has supplemental role in selected cases of BSI with negative and/or discordant results with CECT and 68 Ga-NODAGA-Exendin-4 PET/CT. In malignant insulinoma, 68 Ga-DOTATATE-PET/CT has an additional theranostic potential. Interference due to uptake in non-insulinoma Pan-NET in MEN-1 syndrome may hinder insulinoma localization with 68 Ga-DOTATATE-PET/CT.

Gonadotropins for testicular descent in cryptorchid congenital hypogonadotropic hypogonadism males beyond infancy.

OBJECTIVES: To study the effect of combined gonadotropin therapy (CGT) on testicular descent ± spermatogenesis in congenital hypogonadotropic hypogonadism (CHH) patients with cryptorchidism beyond infancy. METHODS: This retrospective cohort study included CHH patients with cryptorchidism [bilateral (n=5) or unilateral (n=1)] treated with CGT for testicular descent ± pubertal induction. All participants were treated with CGT [human menopausal gonadotropin (hMG) and human chorionic gonadotropin (hCG)] with hMG pretreatment in three and monitored for changes in testicular volume (TV), serum total testosterone (T), serum inhibin-B, and sperm concentration. RESULTS: Complete testicular descent to the scrotal position was achieved in 5/6 patients (10/11 testes) after 4.7 ± 1.6 months of treatment. There was 44 ± 18%, 97.5% (IQR: 44-195), 10-fold (IQR: 3-19.6), and two-fold (IQR: 1.7-9.3) increase in stretched penile length, ultrasound measured TV, T level, and serum inhibin-B from baseline, respectively. In two pediatric cases, testicular descent occurred with isolated hMG therapy. At the last follow up (median: 23.5, IQR: 10.5-38.7 months), all the descended testes remained in scrotal position. In four pubertal/postpubertal age patients, continuous CGT (18-60 months) yielded T and inhibin-B levels of 16.64 ± 1.46 nmol/l and 106 ± 32.6 pg/mL, respectively. All the three patients with available semen analysis had sperm concentration of ≥5 million/mL and one of them achieved paternity. CONCLUSIONS: A trial of CGT before orchiopexy may be considered in CHH males with cryptorchidism even beyond the narrow age-window of infancy. CGT may also have beneficial effects on future spermatogenesis and fertility outcomes in these patients.

Preoperative prediction of parathyroid carcinoma in an Asian Indian cohort.

BACKGROUND: Parathyroid carcinoma (PC) requires preoperative prediction for appropriate surgical management. Differentiation from symptomatic primary hyperparathyroidism (sPHPT) cohort is difficult. METHODS: Patients with sPHPT from a tertiary-care center, Western India, including Cohort-A (n = 19 [10/M; 9/F]) with PC and Cohort-B (n = 93 [33/M; 60/F] with benign parathyroid lesions) were compared to derive predictors for differential diagnosis. RESULTS: There were no differences in clinical or biochemical parameters between the two cohorts. Comparison of CECT parameters showed that irregular shape, tumor heterogeneity, infiltration, short/long-axis ratio >0.76, and long-diameter >30 mm had high negative-predictive value and intratumoral calcification had 100% positive-predictive value to diagnose PC; whereas there were no differences in contrast-enhancement patterns. Long diameter, short/long-axis ratio, and heterogeneity were significant predictors on multivariate analysis. CONCLUSION: It is difficult to predict diagnosis of PC in an Indian sPHPT cohort based on clinical and biochemical parameters, whereas CECT parathyroid-based parameters can aid in diagnosis.

Exendin-4-based imaging in insulinoma localization: Systematic review and meta-analysis.

BACKGROUND AND CONTEXT: Glucagon-like peptide-1 receptor (GLP-1 R) based imaging has shown higher sensitivity for insulinoma localization as compared to other anatomic/functional imaging. METHODOLOGY: We reviewed the published English literature for GLP-1 R targeted imaging in insulinoma in PubMed until August 2020 in accordance with PRISMA guidelines using the MeSH terms "((Exendin-4 PET/CT) OR (Exendin-4 SPECT/CT) OR (GLP-1 R imaging)) AND (Insulinoma)". An individual patient data-metanalysis (IPD-MA) was performed, and performance parameters were calculated for the histopathological diagnosis of insulinoma. MAIN OUTCOME MEASURES: True-positive (TP), false-positive (FP), false-negative (FN), true-negative (TN), sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) for insulinoma localization. RESULTS: A total of 179 cases (316 lesions) from 16 publications were included for IPD-MA. For insulinoma localization, exendin-4-PET/CT (Sn & PPV: 94%) performed better than exendin-4-SPECT/CT (Sn: 63%, PPV: 94%). The Sn was lower in malignant insulinoma cases whereas the Sp was higher in cases with MEN-1 syndrome. With exendin-4-based imaging, FP uptakes in Brunner's gland, normal pancreas, and other ß-cell pathologies and FN results in pancreatic tail lesions and malignancy were seen in a few patients. TN results suggested the correct diagnosis of other endogenous hyperinsulinemic hypoglycaemia (EHH) subtypes. CONCLUSION: For insulinoma localization, exendin-4 PET/CT should be preferred over exendin-4 SPECT/CT because of higher sensitivity and specificity. FP uptakes in Brunner's gland, normal pancreas, and other ß-cell pathologies and FN results in tail lesions, and malignant insulinomas are limitations. Higher specificity for insulinoma localization is particularly useful in patients with MEN-1 syndrome.

Hereditary medullary thyroid carcinoma syndromes: experience from western India.

The data from the Indian subcontinent on Medullary thyroid carcinoma (MTC) and associated endocrinopathies in hereditary MTC (HMTC) syndromes are limited. Hence, we analyzed clinical and biochemical characteristics, management, and outcomes of HMTC and other associated endocrinopathies [Pheochromocytoma (PCC) and Primary hyperparathyroidism (PHPT)] and compared with apparently sporadic MTC. The records of 97 (51 sporadic and 46 hereditary) consecutive MTC patients were retrospectively analyzed. RET mutation was available in 38 HMTC patients. HMTC group was subclassified into Multiple endocrine neoplasia (MEN) 2A index (n = 25), MEN2B index (n = 8), and MEN2A detected by familial screening (n = 12). Patients with HMTC and MEN2B index were younger at presentation than sporadic MTC. MEN2A patients detected by familial screening, but not MEN2A index and MEN2B index patients, had significantly lower serum calcitonin, smaller thyroid nodule size, more frequent early stage presentation (AJCC Stage ≤ II), and higher cure rate than sporadic MTC, which emphasizes the need for early diagnosis. RET (REarranged during Transfection) 634 mutations were the most common cause of HMTC and more frequently associated with PCC (overall 54% and 100% in those aged ≥ 35 years). Patients in ATA-Highest (HST) group had a universal presentation in stage IV with no cure. In contrast, the cure rate and postoperative disease progression (calcitonin doubling time) were similar between ATA-High (H) and ATA- Moderate (MOD) groups, suggesting the need for similar follow-up strategies for the latter two groups. Increased awareness of endocrine (PCC/PHPT) and non endocrine components may facilitate early diagnosis and management.

The utility of 68Ga-DOTATATE PET/CT in localizing primary/metastatic pheochromocytoma and paraganglioma in children and adolescents - a single-center experience.

OBJECTIVES: Pediatric pheochromocytoma and paraganglioma (PPGL) are rare tumors with limited data on the diagnostic performance of 68Ga-DOTA(0)-Tyr(3)-octreotate positron emission tomography-computed tomography (68Ga-DOTATATE PET/CT). We have described our experience of 68Ga-DOTATATE PET/CT in overall and von Hippel Lindau (VHL)-associated pediatric PPGL and compared its sensitivity with that of 131I-meta-iodobenzyl-guanidine (131I-MIBG), 18F-fluorodeoxyglucose PET/CT (18F-FDG PET/CT), and contrast-enhanced CT (CECT). METHODS: Retrospective evaluation of consecutive PPGL patients (age: ≤20 years), who had undergone at least one functional imaging [131I-MIBG, 18F-FDG PET/CT, and/or 68Ga-DOTATATE PET/CT], was done. Composite of anatomical and all the performed functional imaging scans, image comparator (IC), was considered as the gold standard for sensitivity analysis. RESULTS: In a cohort of 32 patients (16 males, age at diagnosis: 16.4 ± 2.68 years), lesion-wise sensitivity of 68Ga-DOTATATE PET/CT (95%) was higher than that of both 18F-FDG-PET/CT (80%, p=0.027) and 131I-MIBG (65%, p=0.0004) for overall lesions, than that of 18F-FDG-PET/CT (100 vs. 67%, p=0.017) for primary PPG, and than that of 131I-MIBG (93 vs. 42%, p=0.0001) for metastases. In the VHL (n=14), subgroup, 68Ga-DOTATATE PET/CT had higher lesion-wise sensitivity (100%) compared to 18F-FDG PET/CT (74%, p=0.045) and 131I-MIBG (64%, p=0.0145). CONCLUSIONS: In our pediatric PPGL cohort, overall lesion-wise sensitivity of 68Ga-DOTATATE PET/CT was higher than that of 18F-FDG PET/CT and 131I-MIBG scintigraphy. Hence, we recommend 68Ga-DOTATATE PET/CT as the preferred modality in pediatric PPGL. 68Ga-DOTATATE PET/CT may evolve as a preferred imaging modality for disease surveillance in VHL.

Prior testosterone replacement therapy may impact spermatogenic response to combined gonadotropin therapy in severe congenital hypogonadotropic hypogonadism.

OBJECTIVE: To study the effect of prior testosterone replacement therapy (TRT) on the spermatogenic response to combined gonadotropin therapy (CGT) in severe and partial phenotype congenital hypogonadotropic hypogonadism (CHH) patients. DESIGN: Retrospective cohort study. SETTING: Tertiary care center. PATIENTS: Patients of CHH without (n = 17) and with prior TRT (n = 18) were subdivided into severe and partial groups, based on mean testicular volume ≤ 3 cc and > 3 cc respectively. INTERVENTION: Participants were treated with hMG at a dose of 75-150 U 3/week and gradually escalating doses of hCG until maximum dose (2000 U 3/week or 5000 U 2/week) or serum total testosterone of ≥ 3.5 ng/ml was reached. MAIN OUTCOME MEASURES: Final mean TV, trough serum testosterone (T), sperm concentration RESULTS: Thirty-five patients (20 severe, baseline mean TV of 3.6 ± 2.7 ml) were started on CGT at 24.8 ± 6.1 years. The median duration of prior TRT was 38 (IQR 10-63.75) months in the exposed group. After 33 ± 12 months, final mean TV was 8.9 ± 5.5 ml, 86% achieved serum testosterone > 3.5 ng/ml and 70% achieved spermatogenesis [median 5 (0-12.6) million/ml]. Patients without prior TRT had significantly higher peak sperm count than those with prior- TRT (median 9 vs 0.05 million/ml, p = 0.004). This effect of prior TRT was more pronounced in severe phenotype patients (median 7 vs 0 million/ml, p = 0.01). CONCLUSION: Prior-TRT may interfere with spermatogenic response to CGT in CHH patients, especially in those with a severe phenotype.

Predictors of Chronic LH-Testosterone Axis Suppression in Male Macroprolactinomas With Normoprolactinemia on Cabergoline.

CONTEXT: Data are limited regarding prevalence, predictors, and mechanisms of persistent hypogonadotropic hypogonadism (HH) in males with a macroprolactinoma who achieve normoprolactinemia on dopamine-agonist therapy. None of the previous studies provide cutoffs to predict the achievement of eugonadism. OBJECTIVE: The objective of this work is to evaluate the prevalence of persistent HH and its determinants in men with a macroprolactinoma who achieve normoprolactinemia on cabergoline monotherapy. DESIGN AND SETTING: This retrospective study with prospective cross-sectional evaluation took place at a tertiary health care center. PATIENTS: Study participants included men with a macroprolactinoma and baseline HH who achieved normoprolactinemia on cabergoline monotherapy. MAIN OUTCOME MEASURES: Outcome measures of this study included the prevalence of persistent HH and its predictors. RESULTS: Thirty participants (age, 38.3 ± 10.1 years) with baseline tumor size of 4.08 ± 1.48 cm and median (interquartile range) prolactin of 2871 ng/mL (range, 1665-8425 ng/mL) were included. Eight of 30 participants achieved eugonadism after a median follow-up of 3 years. Patients with persistent HH had suppression of the luteinizing hormone (LH)-testosterone axis with sparing of other anterior pituitary hormonal axes, including follicle-stimulating hormone-inhibin B. Baseline prolactin (1674 vs 4120 ng/mL; P = .008) and maximal tumor diameter (2.55 ± 0.36 vs 4.64 ± 1.32 cm; P = .003) were lower in patients who achieved eugonadism. Baseline maximal tumor diameter less than or equal to 3.2 cm (sensitivity: 75%, specificity: 63.6%) and serum prolactin less than or equal to 2098 ng/mL (sensitivity: 87.5%, specificity: 77.3%) best predicted reversal of HH. CONCLUSION: Recovery of the LH-testosterone axis occurred in 26.7% of men with a macroprolactinoma who achieved normoprolactinemia on cabergoline monotherapy. Higher baseline tumor size and serum prolactin predict persistent HH. Our data favor chronic functional modification of the hypothalamic-pituitary-gonadal axis over gonadotroph damage as the cause of persistent HH.

177Lu-DOTATATE therapy in metastatic/inoperable pheochromocytoma-paraganglioma.

INTRODUCTION: 177Lu-DOTATATE-based peptide receptor radionuclide therapy (PRRT) is a promising therapy for metastatic and/or inoperable pheochromocytoma and paraganglioma (PPGL). We aim to evaluate the efficacy and safety of and identify predictors of response to 177Lu-DOTATATE therapy in metastatic and/or inoperable PPGL. METHODS: This retrospective study involved 15 patients of metastatic or unresectable PPGL, who received 177Lu-DOTATATE PRRT therapy. Clinical, biochemical (plasma-free normetanephrine), and radiological (anatomical and functional) responses were compared before and after the last therapy. RESULTS: A total of 15 patients (4 PCC, 4 sPGL, 5 HNPGL, 1 PCC + sPGL, 1 HNPGL + sPGL) were included. The median duration of follow up was 27 (range: 11-62) months from the start of PRRT. Based on the RECIST (1.1) criteria, progressive disease was seen in three (20%), stable disease in eight (53%), partial response in one (7%), and minor response in three (20%) and controlled disease in 12 (80%). On linear regression analysis the presence of PGL (P= 0.044) and baseline SUVmax >21 (P < 0.0001) were significant positive predictors of early response to PRRT. Encouraging safety profiles were noted with no long term nephrotoxicity and hematotoxicity. CONCLUSION: 177Lu-DOTATATE therapy is an effective and safe modality of treatment for patients with metastatic/inoperable PPGL. Although it is not prudent to withhold PRRT in metastatic PPGL with baseline SUVmax < 21, baseline SUVmax >21 can be used to predict early response to PRRT.

Exendin-4-based imaging in endogenous hyperinsulinemic hypoglycaemia cohort: A tertiary Endocrine centre experience.

CONTEXT: Insulinoma needs accurate preoperative localization for minimally invasive surgery. Exendin-4-based imaging has shown promising results. OBJECTIVE: To evaluate performance parameters of exendin-4-based imaging in insulinoma localization and compare with other imaging modalities. DESIGN: Retrospective cross-sectional study. PATIENTS: We report 14 patients with endogenous hyperinsulinemic hypoglycaemia (EHH) managed at our centre; in whom, the final diagnosis was insulinoma (n = 11), Munchausen syndrome (MS) (n = 2) and inconclusive (n = 1). Retrospective reporting of CECT, 68 Ga-DOTATATE PET/CT and 68 Ga-NODAGA-exendin-4-PET/CT was done. With per-lesion analysis, performance parameters were calculated for the histopathological diagnosis of insulinoma. MAIN OUTCOME MEASURES: True positive (TP), false positive (FP), false negative (FN), true negative (TN), sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) for insulinoma localization. RESULTS: In our cohort, 12 histopathologically proven insulinoma lesions [(TP): 11 primary lesions, 1 metastasis] were detected in 11 patients, whereas two patients had MS (TN). Sn and PPV were 75% and 100%, 33.3% and 80% and 83.3% and 71.4% for CECT, 68 Ga-DOTATATE PET/CT and 68 Ga-NODAGA-exendin-4-PET/CT, respectively. With exendin-4-based imaging, FP uptake in normal pancreatic tissue and FN results in the pancreatic tail lesion was seen. In one patient, TN result suggested the correct diagnosis of MS. CONCLUSION: 68 Ga-NODAGA-exendin-4-PET/CT has higher sensitivity than 68 Ga-DOTATATE PET/CT and CECT for insulinoma localization. FP uptake in normal pancreas and FN result in tail lesions are limitations of currently utilized exendin-4-based imaging.

Tumor-induced rickets-osteomalacia: an enigma.

Objective We report a case of pediatric thoracic tumor-induced osteomalacia (TIO) causing severe hypophosphatemic rickets with delayed diagnosis and emphasize on timely management of this rare entity. Case presentation A young boy presented with rickets since five years of age. Biochemical evaluation revealed hypophosphatemia, hyperphosphaturia, elevated alkaline phosphatase and normal calcium levels. Initially managed as hereditary hypophosphatemic rickets, he was given phosphorus supplements and calcitriol. Despite the therapy, skeletal deformities worsened requiring surgical corrections. Subsequently, he developed iatrogenic tertiary hyperparathyroidism for which he underwent total parathyroidectomy. Later on, he was found to have fibroblast growth factor-23 secreting thoracic mass (10.5 cm in largest dimension) which was excised with significant post operative improvement. Histopathology showed phosphaturic mesenchymal tumor-mixed connective tissue variant, confirming the diagnosis of TIO. Conclusion TIO, a correctable cause of hypophosphatemic rickets, should be considered in children presenting with hypophosphatemic rickets with evident mass on examination/imaging and in refractory cases.

Management of Insulin Autoimmune Hypoglycaemia: Single-centre experience from Western India with systematic review of world literature.

BACKGROUND: Awareness about Insulin Autoimmune Hypoglycaemia (IAH) and its management remains limited. METHODOLOGY: We describe two cohorts: Cohort 1 (n = 7) included patients with IAH from a tertiary care centre in India and Cohort 2 (n = 294) included systematic review of published English literature from PubMed. They were compared with our insulinoma patients (n = 41). RESULTS: Cohort 1 included seven female patients where two had drugs (carbimazole and thiocolchicoside) as triggering factors. Except for one patient requiring oral prednisolone, others had spontaneous remission. The unique features from our series are being first case series of IAH from India and reporting of second case of thiocolchicoside triggered IAH. Cohort 2 had 294 patients identified from 149 publications. Mean age was 54 ± 19 years. Thirty-five different triggers were identified from 160 cases. Antithyroid drugs were most common triggers in Japanese patients and most common HLA allele was DRB1*0406, while it was alpha-lipoic acid and HLA DRB1*0403 in non-Asians. Serum Insulin >100 µIU/mL and insulin to C-peptide molar ratio (ICMR) >0.25 had specificity of 100% and 97.5%, respectively, for IAH as compared to insulinoma. 56% patients had remission with complex carbohydrate diet and trigger removal while 43% required immunosuppressants. 70% achieved remission within 6 months. CONCLUSIONS: Middle age remains most common age group. Sulfhydryl drugs are most common triggers. Serum Insulin >100 µIU/mL and ICMR > 0.25 in critical sample are good predictors for diagnosis of IAH, which needs to be confirmed by IAA. Conservative management with dietary modification and trigger removal usually suffices in majority. Rests need immunosuppressants.

Tumor induced osteomalacia in head and neck region: single center experience and systematic review.

Tumor-induced osteomalacia in the head and neck region remains a challenging diagnosis to manage. Literature pertaining to management and outcome details remains sparse. We describe two cohorts: cohort 1 included seven patients from a single center in Western India with tumors located in paranasal sinuses (n = 3), intracranial (n = 2) and maxilla (n = 2). The unique features from our series is the management of persistent disease with radiation therapy (n = 2) and peptide receptor radionuclide therapy (PRRT) (n = 1). Cohort two has 163 patients identified from 109 publications for systematic review. Paranasal sinuses, mandible, intracranial disease, maxilla and oral cavity, in descending order, are reportedly common tumor sites. Within this cohort, mean age was 46 ± 14 years at presentation with 44.1% having local symptoms. Duration of symptoms varied from 1 to 240 months. Pre-surgery mean serum phosphorus was 1.4 ± 0.4 mg/dL and median FGF-23 levels were 3.6 (IQR:1.8-6.8) times of normal upper limit of normal. Majority (97.5%) were managed primarily with surgical excision; however, primary radiotherapy (n = 2) and surgery combined with radiotherapy (n = 2) were also reported. Twenty patients had persistent disease while nine patients had recurrence, more commonly noted with intracranial and oral cavity tumors. Surgery was the most common second mode of treatment employed succeeded by radiotherapy. Four patients had metastatic disease. The most common histopathological diagnosis reported is PMT mixed connective tissue, while the newer terminology 'PMT mixed epithelial and connective tissue type' has been described in 15 patients.