IMMUNOHISTOCHEMICAL STUDY OF TESTICULAR TUMOR ON CELLULAR LOCALIZATION OF HCG, α FETOPROTEIN AND β₁ PREGNANCY SPECIFIC GLYCOPROTEIN

Report of 48 Cases

Abstract

In an effort to clarify the cellular localization of human chorionic gonadotropin (HCG), β₁-pregnancy specific glycoprotein (SP₁) and alfafetoprotein (AFP) on germ cell testicular tumor tissue, formalin fixed paraffin embedded tissue specimen of 48 cases germ cell testicular tumors and metastatic tumors to the retroperitoneal lymph nodes were studied with peroxidase antiperoxidase method. The following results were obtained in adult type non seminomatous germ cell tumor tissue from 25cases. Production sites of HCG, SP₁ and AFP were found 16 cases (64%). 14 cases (56%), and 18 cases (69.2%) respectively. However, in 8 cases, infant type germ cell testicular tumor tissue production sites of HCG and SP₁ were not found at all but AFP were found in 4 cases (50%).
Nine out of the 25 cases with adult type non seminomatous germ cell tumor showed an elevation of serum levels of AFP preoperatively, all of the 9 cases demonstrated AFP in their tumor tissue. Tissue existence of AFP in these tumor tissue were correlated well with preoperative high serum marker levels.
Seven out of 25 cases with adult type non seminomatous germ cell tumor showed an elevation of serum levels of β subunit HCG preoperatively, except in one of the 7 cases production sites of HCG was found within their tumor tissue.
One case showed an elevation of the serum level of β subunit HCG preoperatively, in whom production sites of HCG were not found in its tumor tissue, showed a continued elevation of β subunit HCG postoperatively.
It was suspected that residual tumor must be present. Therefore, intensive chemotherapy was done.
Localization of HCG and SP₁ was found almost within syncytiotrophoblastic giant cell like cells among the embryonal cell carcinoma and syncytiotrophoblastic giant cell in choriocarcinoma but in one case that was found within the cell lining a cyst.
Distribution of SP₁ was always narrow compared to HCG.
There were 2 cases in whom production sites of HCG were found but in the adacent tumor tissue SP₁ were not found.
Among the embryonal carcinoma cells, AFP was found with dark brown deposit of Diaminobenzidine or its sparse deposit. As reported earlier, AFP were found within endodermal sinus tumor tissue but within a part of teratoma cell lining the cyst with dark deposit of Diaminobenzidine was also found simultaneously.
Six out of 15 cases of seminoma showed abnormal high serum levels of β subunit HCG preoperatively, 4 of the 6 cases cellular localization of HCG and SP₁ was found within syncytiotrophoblastic giant cell like cells.
Although one case with serum levels of β subunit HCG within normal range one day before operation, HCG and SP₁ were found within syncytiotrophoblastic giant cell like cells. Therefore, diagnosis of pure seminoma requires preoperative measurement of serum levels of β subunit HCG and immunohistochemical method.