Bicalutamide and third-generation aromatase inhibitors in testotoxicosis

Familial Male-limited Precocious Puberty (FMPP) and Testicular Germ Cell Tumors

OBJECTIVE

The purpose of this study is to report development of a malignant testicular germ cell tumor (GCT) in 2 young adult males with familial male-limited precocious puberty (FMPP) because of LHCGR pathogenic variants in 2 families. Secondarily, to study the possible relation between FMPP and testicular tumors and to investigate whether FMPP might predispose to development of malignant testicular tumors in adulthood a literature review is conducted.

METHODS

Data on 6 cases in 2 families are obtained from the available medical records. In addition, a database search is performed in Cochrane, PubMed, and Embase for studies that report on a possible link between FMPP and testicular tumors.

RESULTS

The characteristics of 6 males with FMPP based on activating LH receptor (LHCGR) germline pathogenic variants are described, as are details of the testicular GCTs. Furthermore, a literature review identified 4 more patients with signs of FMPP and a (precursor of) testicular GCT in adolescence or adulthood (age 15-35 years). Additionally, 12 patients with signs of precocious puberty and, simultaneously, occurrence of a Leydig cell adenoma or Leydig cell hyperplasia are reported.

CONCLUSION

There is a strong suggestion that FMPP might increase the risk of development of testicular GCTs in early adulthood compared with the risk in the general population. Therefore, prolonged patient monitoring from mid-pubertal age onward including instruction for self-examination and periodic testicular ultrasound investigation in patients with a germline LHCGR pathogenic variant might contribute to early detection and thus early treatment of testicular GCT.

Precocious Puberty in a Boy With Bilateral Leydig Cell Tumors due to a Somatic Gain-of-Function LHCGR Variant

Context

Autosomal dominant and rarely de novo gain-of-function variants in the LHCGR gene are associated with precocious male puberty, while somatic LHCGR variants have been found in isolated Leydig cell adenomas and Leydig cell hyperplasia. Bilateral diffuse Leydig cell tumor formation in peripheral precocious male puberty has not been reported.

Case Description

We present a boy with gonadotropin-independent precocious puberty and rapid virilization beginning in infancy resistant to standard therapy. Treatment with abiraterone in addition to letrozole and bicalutamide proved effective. Bilateral diffuse Leydig cell tumors were identified at age 5 years.

Results

Whole-genome sequencing of tumor and blood samples was performed. The patient was confirmed to have bilateral, diffuse Leydig cell tumors harboring the somatic, gain-of-function p.Asp578His variant in the LHCGR gene. Digital droplet polymerase chain reaction of the LHCGR variant performed in tumor and blood samples detected low levels of this same variant in the blood.

Conclusion

We report a young boy with severe gonadotropin-independent precocious puberty beginning in infancy who developed bilateral diffuse Leydig cell tumors at age 5 years due to a somatic gain-of-function p.Asp578His variant in LHCGR. The gain-of-function nature of the LHCGR variant and the developmental timing of the somatic mutation likely play a role in the risk of tumor formation. Abiraterone (a CYP17A1 inhibitor), in combination with an antiandrogen, aromatase inhibitor, and glucocorticoid, appears to be an effective therapy for severe peripheral precocious puberty in boys.

Case report: Fluctuating tumor markers in a boy with gonadotropin-releasing hormone-independent precocious puberty induced by a pineal germ cell tumor

GnRH-independent precocious puberty (GIPP) can be the presenting clinical picture experienced by patients with secreting germ cell tumor (GCT). Indeed, as luteinizing hormone (LH) and human chorionic gonadotropin (hCG) share identical α-subunits and similar β-subunits, an increased secretion of β-hCG may result in a precocious activation of Leydig cells. Though the co-occurrence of raised β-hCG levels and signs of precocious virilization usually prompts a complete oncological work-up, the diagnostic and therapeutic management of GCT-induced GIPP may be challenging. We report the case of a 6.2 year-old boy presenting with clinical and biochemical findings consistent with GIPP (discrepancy between overt virilization and pre-pubertal testicular volume, suppressed gonadotropins and remarkably raised testosterone). Brain imaging detected a bilobed cyst of the pineal gland, while serum and cerebrospinal baseline assessment initially ruled out raised alpha-fetoprotein or β-hCG levels. Nevertheless, a strict biochemical follow-up highlighted a fluctuant trend of tumor markers, with a more aggressive behavior and recurrent erections occurring as a result of unpredictable phases of raised testosterone and serum/cerebrospinal β-hCG, followed by sudden spontaneous decrease. Accordingly, a secreting pineal GCT was suspected. Given the fluctuating trend of tumor markers, surgery was initially kept on hold and a combined treatment with bicalutamide (androgen receptor blocker) and anastrozole (aromatase inhibitor) was undertaken in order to prevent the patient from experiencing further virilization and excessive bone age maturation. Subsequently, a progression in the size of the pineal tumor prompted surgical resection and a diagnosis of secreting GCT was histologically confirmed. Accordingly, the patient was started on adjuvant chemo- and radiotherapy. Antineoplastic treatment was followed by persistent and remarkable decrease of tumor markers and by a complete pubertal arrest. We reported the challenging diagnosis of a secreting pineal GCT in a patient with GIPP and a fluctuating trend of tumor markers, testosterone levels and associated clinical signs, hence prompting the indication for a systematic assessment and a strict monitoring whenever a patient with GnRH-independent precocious puberty shows clinical or radiological markers potentially consistent with a GCT.

Long-Term Treatment With Letrozole in a Boy With Familial Male-Limited Precocious Puberty

BACKGROUND

The long-term follow-up in children with familial male-limited precocious puberty (FMPP) who were treated with letrozole, triptorelin, and spironolactone is limited, especially considering the efficiency and safety.

OBJECTIVE

We describe the clinical characteristics and long-term treatment with letrozole on adult height of a boy diagnosed with FMPP, confirmed by analysis of the LHCGR gene.

METHODS

Physical examinations, bone age (BA), testosterone, and gonadotropin levels were measured as well as gene sequencing of the proband and parents.

RESULTS

The boy was referred to the hospital at 3.1 years of age due to peripheral precocious puberty. His height was 116.8cm (+5.1SD) and BA was 9 years. Genetic analysis revealed a patrilineal c.1703C>T.(p.Ala568Val) mutation of the LHCGR gene. After treating with letrozole for 1.6 years, the height according to BA went from -3.52SD to -2.82SD. Triptorelin was added at age 4.7 years based on both the evidence of central puberty and his growth velocity according to BA. During the 6.9 years of treatment, he had a height gain of 51.9cm, and BA increased 5.2 years. At age 10, his present height is 168.7cm (0.05SD) and BA is 14.7 years. No adverse effects of treatment were encountered.

CONCLUSION

A patrilineal mutation of the LHCGR gene has been identified in a boy with FMPP. His height is 168.7cm (-0.05SD) which is approaching his adult height after long-term treatment with letrozole, triptorelin, and spironolactone.

A Case of Familial Male-limited Precocious Puberty with a Novel Mutation

Familial male-limited precocious puberty (FMPP), also known as testotoxicosis, is a rare cause of precocious puberty in males. It is caused by a mutation in the luteinizing hormone/chorionic gonadotropin receptor (LHCGR) gene, resulting in the receptor being constitutively activated. This causes excessive production of testosterone, leading to precocious puberty in males. Generally, boys present with signs of puberty, such as pubic hair growth, acne, and increased height velocity around the age of 2-4 years old. Like any other cause of precocious puberty, the goal of treatment is to prevent virilization and also delay closure of the epiphyseal plates to maintain adult height potential. Treatment, therefore, is aimed at decreasing the effects of testosterone, as well as stopping the conversion of testosterone to estrogen. Little is known about the long-term effects of treatment because the disorder is so rare. However, studies using bicalutamide and anastrozole have been promising. In this report, we present a boy with FMPP with a novel mutation in the LHCGR gene, who has been responding well to therapy using both drugs.

Testotoxicosis without Testicular Mass: Revealed by Peripheral Precocious Puberty and Confirmed by Somatic LHCGR Gene Mutation

Purpose: Testotoxicosis is an autosomal dominant form of limited gonadotropin-independent precocious puberty in boys. It is caused by a heterozygous constitutively activating mutation of the LHCGR gene encoding the luteinizing/hormone receptor (LHR). Some twenty mutations of the LHCGR gene have been reported. Most of them are constitutive mutations isolated from blood leukocyte DNA, although others are somatic, found only in testicular tumoural tissue. In all the previously reported cases of these somatic mutations, the tumour, whether a nodular Leydig cell adenoma or hyperplasia, was easily visible on testicular ultrasonography. The aim of this study was to describe an unusual presentation of a patient with the clinical and hormonal characteristics of testotoxicosis but no well-circumscribed lesion at testicular ultrasonography.Materials and Methods: Molecular analysis of the LHCGR gene was performed by direct sequencing of DNA extracted from peripheral leucocytes and testicular biopsy.Results: Molecular analysis didn't find any LHR mutation in blood, whereas it revealed for the first time a somatic D578H mutation in testicular tissue despite no evidence of a nodular aspect at testis ultrasonography.Conclusions: This observation underlines the need to look for a somatic LHCGR gene mutation from the testicular biopsies of all boys with testotoxicosis with no constitutive LHCGR gene mutation identified from blood DNA, even in the absence of circumscribed testicular lesion at ultrasonography. In addition, based on the known link between LHR mutations and testicular tumourigenesis, yearly ultrasound monitoring of the testes should be considered for these patients.

TESTOTOXICOSIS WITH AN EPISODIC COURSE: AN UNUSUAL CASE WITHIN A SERIES

Objective

To describe an unusual case of familial male precocious puberty (FMPP) characterized by periodic remission compared to a series of boys with typical testotoxicosis.

Methods

Medical records of boys with FMPP followed at our institution from 2001-2017 were reviewed. Variables analyzed included age, family history, physical exam, hormone levels, bone age, and treatment.

Results

A boy of age 2 years 10 months presented with growth acceleration and masturbatory behaviors. On exam, he had 6-mL testes, an enlarged phallus (10.5 × 2.5 cm), and Tanner 2 pubic hair. Testosterone was 242 ng/dL (normal level, ≤30 ng/dL). Genetic testing revealed an Asp578Gly luteinizing hormone receptor mutation confirming FMPP. Anastrozole 1 mg and bicalutamide 50 mg daily were started. During 7.5 years of follow-up, two periods of spontaneous remission occurred lasting >3 years and 10 months, respectively. Both were characterized by prepubertal testosterone levels (10 to 28 ng/dL) and arrested pubertal development off therapy. Relapses were marked by elevated testosterone, growth acceleration, and pubertal progression. Ten additional boys aged 3.46 ± 0.72 years with FMPP were identified, one of whom also had an Asp578Gly mutation. Average testosterone at presentation was 335 ± 193 ng/dL (range, 146 to 778 ng/dL) and average bone age/chronologic age was 2.02 ± 0.47. All were treated with bicalutamide and anastrozole or letrozole.

Conclusion

We report a case of intermittent FMPP in contrast to a series of boys with a characteristic clinical course. To our knowledge, a similar case has not previously been reported. Our case expands the clinical spectrum of this rare condition.

Disorders of Puberty: Pharmacotherapeutic Strategies for Management

During puberty, with activation of the hypothalamic pituitary axis that has been quiescent since the neonatal period, linear growth accelerates, secondary sexual characteristics develop, and adult fertility potential and bone mass are achieved, together with psychosocial and emotional maturation.Disordered pubertal onset and progress, either early or late, presents frequently for endocrine care. Where a disorder is found, due either to a central hypothalamic pituitary cause or to primary gonadal failure, pharmacotherapeutic interventions are required to alter the trajectory of disturbed pubertal onset or progress and for maintenance of adolescent and adult sex hormone status. This paper describes pharmacologic interventions used for pubertal disorders but is not intended to address the diagnostic cascade in detail.

Peripheral precocious puberty including congenital adrenal hyperplasia: causes, consequences, management and outcomes

Peripheral precocious puberty results from peripheral production of sex steroids independent of activation of the hypothalamic-pituitary gonadal axis. It is much less common than central precocious puberty. Causes are variable and can be congenital or acquired. In this review, we will discuss the diagnosis and management of the most common etiologies including congenital adrenal hyperplasia, McCune Albright syndrome, familial male-limited precocious puberty, and adrenal and gonadal tumors.

Bicalutamide as an Androgen Blocker With Secondary Effect of Promoting Feminization in Male-to-Female Transgender Adolescents

PURPOSE

The purpose of the study was to describe the novel use of bicalutamide in transgender youth.

METHODS

This is a retrospective review of patients with gender dysphoria followed in the pediatric endocrine clinic at Riley Hospital for Children.

RESULTS

Of 104 patients with gender dysphoria, 23 male-to-female adolescents received bicalutamide 50 mg daily as a second-line puberty blocker after insurance company denial of a gonadotropin-releasing hormone analog. Six patients received estrogen concurrently. Of 13 patients treated exclusively with bicalutamide seen in follow-up, 84.6% had breast development within 6 months, the majority being ≥ Tanner stage III.

CONCLUSIONS

Bicalutamide may be an alternative to gonadotropin-releasing hormone analogs in transgender male-to-female youth who are also ready to undergo physical transition.

Diseases caused by mutations in luteinizing hormone/chorionic gonadotropin receptor

Accumulating evidence showed that the luteinizing hormone/chorionic gonadotropin receptor (LHCGR) is an essential regulator of sexual development and reproduction from zebrafish to human. Activating and inactivating mutations of LHCGR gene have been identified from patients of different phenotypes. Familial male-limited precocious puberty, Leydig cell hypoplasia, and empty follicle syndrome are caused by LHCGR mutations. More than 50 mutations have been reported from subjects of different ethnic backgrounds. Functional analyses of the mutant LHCGR revealed multiple defects, including cell surface expression, ligand binding, and signaling. The difference of the two native ligands and signaling pathway activated by LHCGR are illustrated. Potential therapeutic implications from the analyses of the naturally occurring LHCGR mutations, such as pharmacological chaperones, are highlighted.

Adult height in patients with familial male-limited precocious puberty and the role of an aromatase inhibitor in patient management

BACKGROUND

There is little adult height data in patients with familial male-limited precocious puberty (FMPP) and no management consensus. We assessed the treatment and adult height in local patients with FMPP and those reported in the literature.

METHODS

Growth data were obtained on four local patients with FMPP and a search performed to obtain management details and adult height data on cases in the literature. UK (90) population standards were used to calculate standard deviation scores (SDS).

RESULTS

Adult height data were available on 25 men with FMPP of whom 21 were treated. Median adult height SDS of patients was -1.5 SD with a mid-parental target of -0.6 SD (p=0.1). Eight patients (32%) had an adult height above the mid-parental target and seven patients (28%) had a height >2 SD below the mean. The median height SD was -0.03 in untreated patients and +0.5 SD in those receiving an aromatase inhibitor. There was no relationship between height and age at presentation.

CONCLUSIONS

Aromatase inhibitor therapy is associated with a positive height outcome in FMPP but the outcome with and without intervention is unpredictable. Clinicians need to be cautious when counselling families about the potential height outcome in FMPP.

Premature Adrenarche

Adrenarche is when a child's adrenal cortex starts to secrete adrenal androgen precursors. Dehydroepiandrosterone (DHEA) is the most abundant product of the adrenal cortex, and is a weak androgen agonist thought to be responsible for the clinical signs of pubarche by conversion to more potent androgens, testosterone, and dihydrotestosterone. DHEA's extra-adrenal sulfation product, dehydroepiandrosterone sulfate, is a stable marker for adrenal androgenic activity. Pubarche is the physical manifestation of androgenic hormone production, and includes the development of pubic and axillary hair, adult body odor, and acne. This stage is usually considered premature if it commences before age 8 years in girls or age 9 years in boys. Premature adrenarche is a diagnosis of exclusion, as true centrally mediated precocious puberty, congenital adrenal hyperplasia, exogenous androgen exposure, and androgen-secreting tumors must be ruled out. Premature adrenarche may be associated with a history of an infant who was small for gestational age at birth who then gained weight rapidly thereafter or became obese. In some instances, premature adrenarche may predict functional ovarian hyperandrogenism in adolescence. Management of premature adrenarche is largely aimed at observation, lifestyle adjustments for weight concerns, and monitoring for future possible persistent androgen excess and insulin resistance. [Pediatr Ann. 2018;47(1):e7-e11.].

Effect of Antiandrogen, Aromatase Inhibitor, and Gonadotropin-releasing Hormone Analog on Adult Height in Familial Male Precocious Puberty

OBJECTIVE

Antiandrogen, aromatase inhibitor, and gonadotropin-releasing hormone analog (GnRHa) treatment normalizes growth rate and bone maturation and increases predicted adult height (AH) in boys with familial male-limited precocious puberty (FMPP). To evaluate the effect of long-term antiandrogen, aromatase inhibitor, and GnRHa on AH, boys with FMPP who were treated were followed to AH.

STUDY DESIGN

Twenty-eight boys with FMPP, referred to the National Institutes of Health, were started on antiandrogen and aromatase inhibitor at 4.9 ± 1.5 years of age; GnRHa was added at 6.9 ± 1.5 years of age. Treatment was discontinued at 12.2 ± 0.5 years of age (bone age, 14.4 ± 1.3). AH was assessed at 16.4 ± 1.3 years of age (bone age, 18.5 ± 0.6).

RESULTS

AH (mean ± SD) for all treated subjects was 173.6 ± 6.8 cm (-0.4 ± 1.0 SD relative to adult US males). For 25 subjects with pretreatment predicted AH, AH significantly exceeded predicted AH at treatment onset (173.8 ± 6.9 vs 164.9 ± 10.7 cm; P < .001), but fell short of predicted AH at treatment discontinuation (177.3 ± 9.0 cm; P < .001). For 11 subjects with maternal or sporadic inheritance, the mean AH was 3.1 cm (0.4 SD score) below sex-adjusted midparental height (175.4 ± 5.8 vs 178.5 ± 3.1 cm [midparental height]; P = .10). For 16 subjects with affected and untreated fathers, AH was significantly greater than fathers' AH (172.8 ± 7.4 vs 168.8 ± 7.2 cm; P < .05).

CONCLUSIONS

Long-term treatment with antiandrogen, aromatase inhibitor, and GnRHa in boys with FMPP results in AH modestly below sex-adjusted midparental height and within the range for adult males in the general population.

Cosegregation of a novel mutation in the sixth transmembrane segment of the luteinizing/choriogonadotropin hormone receptor with two Brazilian siblings with severe testotoxicosis

PURPOSE

Testotoxicosis is an autosomal dominant form of gonadotropin-independent precocious puberty caused by heterozygous constitutively activating mutations of the luteinizing hormone/choriogonadotropin receptor (LHCGR) gene. The aim of this study was to describe two Brazilian siblings with testotoxicosis, to confirm the molecular diagnosis, and to perform an in silico analysis of a novel mutation in the hot spot of the LHCGR gene.

MATERIALS AND METHODS

Molecular analysis of the mutation on the LHCGR gene was performed by direct Sanger sequencing, followed by an in silico analysis using HOPE bioinformatics tool to predict a functional defect of the mutant.

RESULTS

Both patients presented with gonadotropin-independent precocious puberty before the age of four years. Genetic analysis revealed a novel non-maternally inherited p.Asp578Val mutation of the LHCGR gene. An in silico analysis showed that the p.Asp578Val mutation disturbed amino acid physicochemical features regarding its size, charge, and hydrophobicity value.

CONCLUSIONS

Clinical and hormonal profile of the siblings here evaluated was not different while compared to those patients previously described. An in silico mutation analysis reinforced the causative role of recurrent activating mutations in the intracellular loop and transmembrane helices of the LHCGR. The segregation of this mutation with the offsprings' phenotype indicated that it is causative.

Treatment of Peripheral Precocious Puberty

There are many etiologies of peripheral precocious puberty (PPP) with diverse manifestations resulting from exposure to androgens, estrogens, or both. The clinical presentation depends on the underlying process and may be acute or gradual. The primary goals of therapy are to halt pubertal development and restore sex steroids to prepubertal values. Attenuation of linear growth velocity and rate of skeletal maturation in order to maximize height potential are additional considerations for many patients. McCune-Albright syndrome (MAS) and familial male-limited precocious puberty (FMPP) represent rare causes of PPP that arise from activating mutations in GNAS1 and the LH receptor gene, respectively. Several different therapeutic approaches have been investigated for both conditions with variable success. Experience to date suggests that the ideal therapy for precocious puberty secondary to MAS in girls remains elusive. In contrast, while the number of treated patients remains small, several successful therapeutic options for FMPP are available.

Testotoxicosis: Report of Two Cases, One with a Novel Mutation in LHCGR Gene

Testotoxicosis is a rare disorder which presents as isosexual peripheral precocious puberty in males. Despite the pattern of autosomal dominant inheritance, sporadic cases also may occur. Due to activating mutation in luteinizing hormone (LH))/choriogonadotropin receptor (LHCGR) gene, early virilization and advancement in bone age are common with increased serum testosterone levels above adult ranges, despite low LH and follicular-stimulating hormone (FSH) levels. There are different treatment regimens, such as combination of bicalutamide (antiandrogen agent) and a third-generation aromatase inhibitor, that are reported to be well-tolerated and successful in slowing bone age advancement and preventing progression of virilization. We report here two patients who presented with peripheral precocious puberty and an activating mutation in the LHCGR gene: one with a family history and previously determined mutation and the other without family history and with a novel mutation (c.830G>T). Combination of bicalutamide+anastrozole was ineffective in slowing pubertal progression and bone age. Short-term results were better with ketoconazole.

Novel approaches to short stature therapy

Besides growth hormone, several pharmaceutical products have been investigated for efficacy and safety in increasing short term growth or adult height. Short-term treatment with testosterone esters in boys with constitutional delay of growth and puberty is efficacious in generating secondary sex characteristics and growth acceleration. The addition of oxandrolone to growth hormone (GH) in Turner syndrome has an additive effect on adult height gain. Treatment with GnRH analogs is the established treatment of central precocious puberty, and its addition to GH therapy appears effective in increasing adult height in GH deficient children, and possibly short children born SGA or with SHOX deficiency, who are still short at pubertal onset. Aromatase inhibitors appear effective in several rare disorders, but their value in increasing adult height in early pubertal boys with GH deficiency or idiopathic short stature is uncertain. A trial with a C-natriuretic peptide analog offers hope for children with achondroplasia.

Third-generation Aromatase Inhibitor Improved Adult Height in a Japanese Boy with Testotoxicosis

In this study, we report a Japanese boy with testotoxicosis due to a heterozygous mutation [p. A572V] in the LH/CGR gene, who was the first boy treated with a third-generation aromatase inhibitor (AI) and reached his adult height in Japan. He showed accelerated growth and rapid penile growth from 3 yr of age and was diagnosed as having testotoxicosis. Combined treatment with anastrozole and spironolactone was started when he was 7 yr old and 145.8 cm (+4.45 SD) tall, at which point his bone age (BA) was 13.5 yr. His predicted adult height (PAH) was estimated to be 158.3 cm. The combined treatment was continued until he was 13 yr old and 166.5 cm tall, with his BA being 15.5 yr. He reached his adult height of 166.9 cm at 15 yr of age. Combined treatment with anastrozole and spironolactone successfully decelerated BA advancement, prolonged pubertal period and improved adult height.

Familial male-limited precocious puberty in neurofibromatosis type I

Precocious puberty in patients with neurofibromatosis type 1 (NF-1) is predominantly central in origin, with intracranial pathologies like optic glioma. We describe one patient with NF-1 who presented with precocious puberty with the eventual diagnosis of familial male-limited precocious puberty and share the potential pitfalls. He presented at 7 years of age with growth spurt and pubertal genitalia development with enlarged testicular volume of 7 mL, but LHRH stimulation test revealed blunted luteinizing hormone and follicle-stimulating hormone peak suggestive of a peripheral cause, contrary to the expectation due to the background of NF-1. Testosterone level was elevated with bone age advancement by 2 years. Genetic analysis revealed a previously reported heterozygous missense mutation of the luteinizing hormone/choriogonadotropin receptor gene Ala572Val. His father was also heterozygous for the same mutation but was apparently asymptomatic and not short.

CONCLUSION

Our report illustrates two potential pitfalls in the clinical evaluation of patients with familial male-limited precocious puberty (FMPP). Firstly, patients with FMPP will have mild to moderately enlarged testes and should not be wrongly diagnosed as central precocious puberty without the gonadotropin-releasing hormone stimulation test. Secondly, family members with the same mutation may have different phenotypic severities, where some male carriers may have subtle features.

Precocious puberty--perspectives on diagnosis and management

The term 'precocious puberty' signifies the onset of secondary sexual characters before the age of 9 y in boys and 8 y in girls. Menarche before 9.5 y is also considered precocious. These definitions are constantly evolving due to the secular trends observed all over the world. It is crucial to decide whether the child has central (gonadotropin-dependent, GDPP) or peripheral (gonadotropin-independent, GIPP) form of precocious puberty. Some benign conditions such as premature thelarche and premature pubarche may mimic precocious puberty. A systematic approach with detailed history and clinical examination helps to arrive at a diagnosis in most cases. An underlying neurologic disorder is more likely in a very young boy. Basal LH level is the best screening test to diagnose GDPP. LH level less than 0.1 IU/L by a very sensitive assay indicates prepubertal stage. Stimulation tests using gonadotropin releasing hormone (GnRH) or its analog (GnRHa), leuprolide help to confirm the diagnosis of GDPP. High resolution MRI of brain helps to detect abnormalities in hypothalamus and pituitary region. GnRH analogs (GnRHa) are the only effective treatment for GDPP at present. In girls, breast size may regress; menses ceases and vaginal mucosa becomes non-estrogenized. In boys testicular volumes remain static or decrease and genital growth regresses. The effects of GnRH analogs are reversible on discontinuation of therapy, with restoration of normal function within 3 mo after stopping treatment. Treatment of GIPP however is far from satisfactory.

Toxicological assessment of drugs that affect the endocrine system in puberty-related disorders

INTRODUCTION

Toxicologists must ensure that clinical risk-to-benefit analysis should be made both for genders and age groups, with any treatment. Puberty concerns physiological changes leading to organism's maturation. Pubertal growth disorders are increasing in last decades: besides causing physical and psychological distress, they may signal underlying endocrine-metabolic abnormalities with serious health consequences later on. Therapeutic approaches for some health conditions in childhood and adolescence are considered.

AREAS COVERED

The authors discuss how some diseases and treatments can impact pubertal growth. The authors look at particular immunological disorders such as asthma and how both the disease and treatment affects pubertal growth. They also discuss how the provision of available data can help to assess the dose-response of the drug, in these cases, and minimize the chance of side effects. The authors also discuss pediatric inflammatory bowel disease and how both the disease and treatment can mitigate the growth delay. Last, but not least, the authors discuss how the effects of the drugs used in the treatment of psychiatric disorders may accentuate endocrine issues in juvenile patients. Hyperprolactinemia induction by some antipsychotics is highlighted as an example.

EXPERT OPINION

Appropriate risk-benefit analysis of drugs prescribed during childhood and adolescence and intended to be used in the long term is required. Furthermore, future treatment strategies and safer compounds development should be supported by the knowledge of mechanisms underlying adverse side effects in pubertal growth and development.

Treatment and outcomes of precocious puberty: an update

Precocious puberty is a common problem affecting up to 29 per 100,000 girls per year. The earliest identified neuroendocrine change in early puberty thus far is increased kisspeptin secretion from the arcuate nucleus and the anteroventral paraventricular nucleus of the hypothalamus. The regulation of kisspeptin secretion is not well understood, but neurokinin B and dynorphin provide autocrine regulation. The etiologies of precocious puberty may be subdivided into GnRH-dependent and GnRH-independent causes. GnRH-dependent precocious puberty, often called central precocious puberty (CPP), is usually treated with GnRH analogs. Newer developments in the treatment of CPP include expanded data on the safety and efficacy of the subdermal histrelin implant, which is useful for long-term treatment, although removal may be difficult in some cases. Preliminary data suggest that the implant may be left in place for up to 2 years without loss of biochemical suppression. In the last 2 years, more data have been published concerning extended-release leuprolide acetate injections that indicate that the 11.25-mg dose may not provide full biochemical suppression but may clinically suppress signs of puberty, including the accelerated growth velocity and advanced skeletal maturation seen in CPP. Treatment options for familial male-limited precocious puberty and McCune-Albright syndrome are expanding as well, although data are preliminary. Long-term outcome studies of CPP indicate overall good menstrual and reproductive function, but the prevalence of polycystic ovary syndrome may be higher than in the general population. Remarkably few studies have evaluated the behavioral and psychological outcomes of precocious puberty, in contrast to early normal maturation. Additional outcome studies of endocrine, metabolic, and psychological effects of CPP are clearly needed.

Characterization and management of testicular pathology in McCune-Albright syndrome

CONTEXT

The testicular phenotype in McCune-Albright syndrome (MAS) has not been well characterized. Boys present with a relatively low incidence of precocious puberty in comparison with girls. Radiographic and histological studies are limited to small series and case reports, which report testicular microlithiasis and Sertoli cell hyperplasia.

OBJECTIVE

Our objective was to characterize the biochemical, radiological, and histological spectrum and clinical management of testicular pathology in males with MAS.

PATIENTS, DESIGN, AND SETTING

Fifty-four males with MAS participated in this prospective cohort study at a clinical research center.

INTERVENTION

Evaluation included testicular exam, pubertal staging, testicular ultrasound, measurement of LH, FSH, and testosterone. Orchiectomies were performed when considered clinically indicated.

MAIN OUTCOME MEASURE

Prevalence and characterization of ultrasound lesions with correlation to histology were evaluated.

RESULTS

Of 54 males, 44 (81%) presented with ultrasound abnormalities including hyperechoic lesions (49%), hypoechoic lesions (30%), microlithiasis (30%), heterogeneity (47%), and focal calcifications (11%). Eight subjects underwent orchiectomy revealing large foci of Leydig cell hyperplasia, which could not be definitively distinguished from Leydig cell tumor. After no subjects developed clinical malignancy, a conservative approach was instituted, and subsequent subjects were followed with serial imaging. Testosterone and gonadotropins were normal in subjects without precocious puberty or pituitary disease. Eleven (21%) presented with precocious puberty, and a combination of aromatase inhibitors, androgen receptor blockers, and leuprolide resulted in improved predicted adult height. In addition, the first cases of testicular adrenal rest and bilateral germ cell tumors in association with MAS are presented.

CONCLUSIONS

Contrary to prevailing thinking, the incidence of gonadal pathology in MAS is equal in males and females. The predominant histopathological finding was Leydig cell hyperplasia, which carries a low risk of malignant transformation and can be managed conservatively.

Combined treatment with bicalutamide and anastrozole in a young boy with peripheral precocious puberty due to McCune-Albright Syndrome

McCune-Albright Syndrome (MAS) is a congenital endocrine disorder due to mosaic tissutal hyper-function. We describe a boy with a molecularly confirmed MAS, clinically evident with congenital café-au-lait spots, bone fibrous dysplasia, hyperthyroidism, and renal phosphate wasting syndrome. At 4.6 years of age he disclosed a rapid progression of peripheral puberty, so we decided to treat him with bicalutamide 25 mg/day and anastrozole 1 mg/day. Combined third generation aromatase inhibitors - competitive androgen receptor blockers were employed in familial male precocious puberty (FMPP). Combined treatment was performed for 49 months from the age of 4.6 to 6.7 years. The patient underwent clinical, laboratory, and instrumental evaluation twice a year from the first admission to the current age. This treatment caused a rapid normalization of growth velocity, subsequent reduction of penile androgenization, and stabilization of testicular volume. The therapy was well tolerated for all its duration and neither side effects, nor secondary hypothalamic activation were noted. This report provides further evidence of effectiveness and safety of combined third generation aromatase inhibitors - competitive androgen receptor blockers in male precocious peripheral puberty, firstly employed in male MAS, and contributes to expand the spectrum of disorders in which their employment may reveal promising.

Aromatase inhibitors in pediatrics

Aromatase, an enzyme located in the endoplasmic reticulum of estrogen-producing cells, catalyzes the rate-limiting step in the conversion of androgens to estrogens in many tissues. The clinical features of patients with defects in CYP19A1, the gene encoding aromatase, have revealed a major role for this enzyme in epiphyseal plate closure, which has promoted interest in the use of inhibitors of aromatase to improve adult height. The availability of the selective aromatase inhibitors letrozole and anastrozole--currently approved as adjuvant therapy for breast cancer--have stimulated off-label use of aromatase inhibitors in pediatrics for the following conditions: hyperestrogenism, such as aromatase excess syndrome, Peutz-Jeghers syndrome, McCune-Albright syndrome and functional follicular ovarian cysts; hyperandrogenism, for example, testotoxicosis (also known as familial male-limited precocious puberty) and congenital adrenal hyperplasia; pubertal gynecomastia; and short stature and/or pubertal delay in boys. Current data suggest that aromatase inhibitors are probably effective in the treatment of patients with aromatase excess syndrome or testotoxicosis, partially effective in Peutz-Jeghers and McCune-Albright syndrome, but probably ineffective in gynecomastia. Insufficient data are available in patients with congenital adrenal hyperplasia or functional ovarian cysts. Although aromatase inhibitors appear effective in increasing adult height of boys with short stature and/or pubertal delay, safety concerns, including vertebral deformities, a decrease in serum HDL cholesterol levels and increase of erythrocytosis, are reasons for caution.

Aromatase inhibitors in men: effects and therapeutic options

Aromatase inhibitors effectively delay epiphysial maturation in boys and improve testosterone levels in adult men Therefore, aromatase inhibitors may be used to increase adult height in boys with gonadotropin-independent precocious puberty, idiopathic short stature and constitutional delay of puberty. Long-term efficacy and safety of the use of aromatase inhibitors has not yet been established in males, however, and their routine use is therefore not yet recommended.