Macro-orchidism: a clinicopathological approach

Macroorchidism in an Indian boy with McCune-Albright syndrome

McCune-Albright syndrome (MAS) is defined by the clinical triad of fibrous dysplasia of bone (FD), café-au-lait spots and precocious puberty (PP). It is a rare disease with estimated prevalence between 1/100,000 and 1/1,000,000. The authors report a case of MAS in an Indian boy who had history of unilateral macroorchidism (but no other signs of MAS) since birth, then presented with PP, FD and café-au-lait spots at 6 years of age. On examination he had asymmetry of the face, café-au-lait spots and signs of sexual precocity with a right testicular volume of 25 ml (left 8 ml). Investigations revealed suppressed gonadotropins with elevated testosterone levels. Skeletal survey showed dysplastic changes involving multiple bones and advanced bone age. Reports of MAS in a boy with unilateral macroorchidism are scarce. Thus, unilateral macroorchidism at birth in a baby may be a feature of MAS and should be followed up with care.

McCune-Albright syndrome in a boy may present with a monolateral macroorchidism as an early and isolated clinical manifestation

BACKGROUND

Testis enlargement in McCune-Albright syndrome (MAS) is generally bilateral and associated with clinical and biochemical manifestations of sexual precocity.

CASE REPORT

We describe for the first time an unreported clinical expression of MAS in a 4.6-year-old boy presenting with monolateral testis enlargement and no signs of sexual precocity or other clinical manifestations of MAS at the time of presenting with macroorchidism. Both testosterone and LHRH-stimulated gonadotropin levels were in the prepubertal range. Serum inhibin B was increased to a pubertal level indicating Sertoli cell activation. The histological and immunocytochemical evaluation of the enlarged testis revealed Sertoli cell hyperplasia with no mature Leydig cells. Mutation R201C of GNAS1 gene, classically responsible for MAS, was identified in DNA samples from the right testis biopsy and leukocytes.

CONCLUSIONS

(a) MAS should be taken into consideration in the clinicopathological approach to a boy with monolateral macroorchidism; (b) testicular enlargement may be only the presenting clinical manifestation of MAS and is not necessarily linked to manifestations of peripheral precocious puberty; (c) testicular autonomous hyperfunction in MAS may be restricted to Sertoli cells, as also demonstrated previously by others.

Testicular biopsy. Contemporary interpretation

Biopsy of the testis is not universally accepted in contrast with biopsies of other organs. The pathologist studies and reports on the pathophysiology of the testicular biopsy specimen. Methodology requires the inclusion of qualitative and quantitative studies, the evaluation of the lesion's evolution (prognosis), and, often, therapeutic advice regarding treatment. Cooperation between pathologists and clinicians optimizes the utility of the biopsy for the patient.