SAT-073 Testicular Abnormalities in the Absence of Precocious Puberty in Mccune-Albright Syndrome

Background: Mc-Cune Albright Syndrome (MAS) is a rare disorder characterized by skeletal lesions, skin hyperpigmentation and hyperfunctioning endocrinopathies. Gonadotropin-independent precocious puberty is the most common endocrinopathy, known to be more common in females than males, but little is known about male gonadal pathology in MAS. Clinical case: 3-year-old boy presented with worsening unilateral limp and was noted to have a pathologic femoral fracture. Bone scan demonstrated extensive fibrous dysplasia in the long bones and skull base. He had a large café au lait spot on the back. He was diagnosed with MAS on clinical criteria. At 4 years of age, initial exam was normal without signs of precocious puberty. Linear growth followed the 70(th) percentile, on track for his genetic background (mid parental height 70(th) percentile). Initial hormonal work up showed normal thyroid function, prolactin, growth factors and pre-pubertal gonadotropins and testosterone. At 6 years of age, he started to demonstrate bilateral testicular enlargement of 4-6 mL with pubic hair Tanner stage I. Bone age was concordant with chronologic age. Gonadotropins and testosterone level were pre-pubertal. Testicular ultrasound showed bilateral enlargement with punctuate densities without evidence of hydrocele or mass. By 8 years of age, he had further testicular enlargement to 8 mL bilaterally, normal penile length 5.5 cm (6.2 ± 1.0) and no pubic hair. Biochemical evaluation showed normal thyroid function and pre-pubertal gonadotropins and testosterone. Repeat testicular ultrasound showed heterogeneous echotexture representing microlithiasis, without a focal mass. Conclusion: Macroorchidism can be present in the absence of gonadotropin independent precocious puberty in MAS. Testicular ultrasound evaluation is important, as hyper-hypoechoic lesions, bilateral microlithiasis, focal calcifications, are the most common testicular abnormality in males with MAS. Microlithiasis, due to calcium deposits within the seminiferous tubules, have been described often in this condition, and should be considered a marker of male MAS. The natural history of male fertility and testicular cancer risk in the context of microlithiasis and testicular calcifications is unknown. Close observation and testicular imaging at baseline and after age 5, to characterize subclinical involvement, are an appropriate course to follow.