Gonadotropin-independent precocious puberty associated with a somatic activating mutation of the LH receptor gene: detection of a mutation present in only a small fraction of cells from testicular tissue using wild-type blocking polymerase chain reaction and laser-capture microdissection

A Multicenter Retrospective Review of Pediatric Leydig Cell Tumor of the Testis

Leydig cell tumors (LCTs) are rare tumors arising from testosterone-producing Leydig cells. Although LCTs are usually benign, malignancy has been reported in 10% of cases in adults, and local recurrence or metachronous tumors of the contralateral testis have been described. Radical orchiectomy is the current standard of care. We report on 12 children with LCT at 3 institutions between 2000 and 2016. Presenting symptoms included precocious puberty, palpable testicular mass, and scrotal swelling. Radical orchiectomy was performed in 9 patients. Three patients were treated with enucleation. All patients were alive at last follow-up without evidence of local recurrence or metastasis.

Constitutive luteinizing hormone receptor signaling causes sexual dysfunction and Leydig cell adenomas in male mice

The luteinizing hormone receptor (LHCGR) is necessary for fertility, and genetic mutations cause defects in reproductive development and function. Activating mutations in LHCGR cause familial male-limited precocious puberty (FMPP). We have previously characterized a mouse model (KiLHRD582G) for FMPP that exhibits the same phenotype of precocious puberty, Leydig cell hyperplasia, and elevated testosterone as boys with the disorder. We observed that KiLHRD582G male mice became infertile by 6 months of age, although sperm count and motility were normal. In this study, we sought to determine the reason for the progressive infertility and the long-term consequences of constant LHCGR signaling. Mating with superovulated females showed that infertile KiLHRD582G mice had functional sperm and normal accessory gland function. Sexual behavior studies revealed that KiLHRD582G mice mounted females, but intromission was brief and ejaculation was not achieved. Histological analysis of the reproductive tract showed unique metaplastic changes resulting in pseudostratified columnar epithelial cells with cilia in the ampulla and chondrocytes in the penile body of the KiLHRD582G mice. The infertile KiLHRD582G exhibited enlarged sinusoids and a decrease in smooth muscle content in the corpora cavernosa of the penile body. However, collagen content was unchanged. Leydig cell adenomas and degenerating seminiferous tubules were seen in 1-year-old KiLHRD582G mice. We conclude that progressive infertility in KiLHRD582G mice is due to sexual dysfunction likely due to functional defects in the penis.

Leydig cell tumor in a patient with 49,XXXXY karyotype: a review of literature

49,XXXXY pentasomy or Fraccaro's syndrome is the most severe variant of Klinefelter's syndrome (KS) affecting about 1/85000 male births. The classical presentation is the triad: mental retardation, hypergonadotropic hypogonadism and radio ulnar synostosis. Indeed, the reproductive function of Fraccaro's syndrome is distinguished from KS. Besides, Leydig cell tumors are described in cases of KS, but never documented in the Klinefelter variants.We describe a young adult of 22 years old who presented with hyper gonadotropic hypogonadism, delayed puberty and bilateral micro-cryptorchidism. Chromosomal pentasomy was confirmed since infancy. Bilateral orchidectomy revealed a unilateral well-circumscribed Leydig cell tumor associated with bilateral Leydig cell hyperplasia.Inspired from reporting the first case of Leydig cell tumor in a 49,XXXXY patient, we summarize the particularities of testicular function in 49,XXXXY from one side, and the risk and mechanisms of Leydig cell tumorigenesis in Klinefelter variants on the other side. The histological destructions in 49,XXXXY testes and hypogonadism are more profound than in Klinefelter patients, with early Sertoli, Leydig and germ cell destruction. Furthermore, the risk of Leydigioma development in KS and its variants remains a dilemma. We believe that the risk of Leydigioma is much higher in KS than the general population. By contrast, the risk could be lower in the Klinefelter variants with more than 3 supplementary X chromosomes, owing to an earlier and more profound destruction of Leydig cells rendering them irresponsive to chronic Luteinizing hormone (LH) stimulation.

Leydig cell tumors in children: contrasting clinical, hormonal, anatomical, and molecular characteristics in boys and girls

OBJECTIVE

To analyze the clinical, hormonal, anatomical, and molecular characteristics of Leydig cell tumors, a very rare cause of progressive hyperandrogenism in children.

STUDY DESIGN

Description of a 9-year-old boy with isosexual precocious pseudopuberty, and of a 12-year-old girl with rapidly progressive virilization, both due to a pure Leydig cell tumor. Review of all cases of pediatric Leydig cell tumors published since 1999 (when the first somatic mutations of the luteinizing hormone receptor were described) and reporting hormonal and/or molecular data.

RESULTS

Boys (n = 24) are younger than girls (n = 12) at diagnosis (median 6.5 vs 13.0 years, P = .04). Plasma gonadotrophins are more often completely suppressed in boys (6 cases) than in girls (2 cases). Pure Leydig cell tumors are exceedingly rare in girls (2 cases), who most often have Sertoli-Leydig tumors. These tumors affect either testis equally (11 left, 13 right) but occur more often in the left ovary (8 left, 3 right). Activating mutations of the alpha-subunit of the G(s) stimulatory protein have not been found in either boys or girls and activating mutations of the luteinizing hormone receptor have only been found in boys.

CONCLUSIONS

Leydig cell tumors in children display clinical, hormonal, anatomical, and molecular sexual dimorphism.