and Pilar González-Peramato2
Most tumors containing both germ cell and sex cord-stromal elements are characterized by combining in a harmonic way, in nests or cords, two cell types, germ cells (some similar to gonocytes) and cells of the sexual cords (similar to immature granulosa cells). This is the case of gonadoblastomas. The three cases of gonadoblastomas chosen are representative of the different gonads in which it can develop, one on a streak gonad of a patient with Frasier syndrome (gonadal dysgenesis 46, XY and nephropathy), another on a dysgenetic testis with AMH (dysgenetic male pseudohermaphroditism) deficit, and the third one in a gonad associated with seminoma of a patient with 46,XY gonadal dysgenesis. Throughout the three cases we expose: (a) the different patterns that may be present in the gonadoblastomas (nodular, dissecting) and the relationship with the undifferentiated gonadal tissue (UGT); (b) the evolution of this neoplasia either towards regression by calcification, or progression to a germ cell tumor; and (c) the differential diagnosis with other entities with which the gonadoblastoma has certain morphological similarity. This is the case of Sertoli cell nodules with infiltration by GCNIS or gonadoblastoid testicular dysplasia.
Case 76. Gonadoblastoma in a Dysgenetic Testis
Clinical case. A 6-month-old patient with bilateral cryptorchidism. On the left side, in the surgical exploration, a cord-like structure that was interpreted as a uterine tube was found attached to the testicle. This testicle and the tube were removed. The phenotype was male and the karyotype 46, XY.
Comments. The gonad has two features of interest. First, it meets the characteristics of a dysgenetic testicle; second, it is a carrier of a gonadoblastoma. The dysgenetic testicle is defined by the presence of three findings: thin and poorly collagenized albuginea, absence of separation plane of the albuginea and testicular parenchyma, and the presence of seminiferous tubules inside. As the normal collagenization of the albuginea is dependent on AMH, the abnormal thickness and collagenization of the same is showing that either Sertoli cells are unable to produce AMH by a mutation in AMH gene or there is a resistance in the target structures due to a deficit of type II receptor of this hormone. Another logical consequence is the ipsilateral persistence of the uterine tube and in some cases of the uterus (male with uterus). The presence of bilateral cryptorchidism associated on one side with a uterine horn is characteristic of persistent Müllerian duct syndrome. The second and not least important fact of interest is that the testicle shows a gonadoblastoma. A rare finding in the testis of these patients, gonadoblastoma is much more frequent in the DSD with streak gonads. Also about a characteristic of its rarity is the fact that when these patients develop an infiltrative germ cell tumor (the risk is 18%) most of them do it to form a GCNIS.