The frequency and morphology of "giant spermatogonia" in the human testis

Number and DNA Content of Hypertrophic Spermatogonia in Normal and Cryptorchid Human Testes

The number and the DNA content of hypertrophic spermatogonia were studied in normal and cryptorchid testes. The number of hypertrophic spermatogonia in cryptorchid testes is higher than in control testes at the same age. This finding suggests alterations in the spermatogonia of cryptorchid males. The results show a polyploid DNA content in more than 80% of hypertrophic spermatogonia in both normal and cryptorchid testes. There were hypertrophic spermatogonia with a DNA content between 2c and 4c (0.5%) and between 4c and 8c (9%). These spermatogonia might be cells in the S phase of the cell cycle.

Primary testicular lesions are associated with testicular germ cell tumors of adult men

The present study aims to establish the nature and frequency of testicular lesions in the parenchyma adjacent to testicular germ cell tumors (TGCT) to improve understanding of the factors involved in the development of testicular cancer. Fifty-three cases of TGCT that were fixed in both neutral-buffered formalin and Bouin solution, allowing for the nuclear characterization of Sertoli cells (SCs), were included in this study. In each case, at least 3 sections of different areas of preserved parenchyma surrounding the TGCT were studied. We found Leydig cell hyperplasia, microlithiasis, angiopathy, adenomatous hyperplasia of the rete testis, SC nodules, SC dysgenesis and involution, SC-only tubules, tubular atrophy, adluminal compartment lesions, hypospermatogenesis associated with spermatocyte sloughing, spermatogonial maturation arrest, and hypertrophic and multinucleated spermatogonia. These lesions were found in regions both adjacent and far away from the tumoral mass, and abnormal seminiferous tubules were found intermingled with those showing complete spermatogenesis, suggesting that these lesions are primary and existed before the development of the tumor. Our study suggests that SCs might play a more important role in the development of testicular tumors than previously thought. Our data supports the hypothesis that there is an abnormal differentiation of SCs, caused either by genetic anomalies or by environmental agents during fetal life. This abnormal SC differentiation may cause not only primary spermatogenesis failure and spermatogenesis arrest at different levels, but may also contribute to the poor differentiation of gonocytes into spermatogonia. The abnormal gonocyte differentiation might favor the development of dysplastic germ cells that may later transform into intratubular germ cell neoplasia, unclassified type.

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.

Multinucleated spermatocytes and spermatids in human seminiferous tubules

The cytology of multinucleated spermatocytes and spermatid giant cells in the seminiferous tubules of men with oligozoospermia and of men older than 65 years has been investigated electron microscopically. Two different processes which are responsible for the origin of multinucleated germ cells have been analysed: Defects of the intercellular bridges (IB): they move apart and thus allow the confluence of one clone's cells to symplasms. The confluence of membranes: within one clone the membranes of neighbouring germ cells are dissolved and thus intercellular bridges are found in the cytoplasm of the resulting giant cells. The spermatid giant cells reveal a new organization of the cell nuclei and the cell organelles. Yet they disintegrate in the lumen of the seminiferous tubules. The appearance of giant cells therefore is an expression of the germ cell degeneration.

The significance of giant cells in human testicular seminomas. A clinico-pathological study

In order to study the nature and significance of various giant cells encountered in seminomatous tumors of the testis, we reviewed the morphology of 243 consecutive pure seminomas and 107 combined (mixed) tumors, as well as the long term clinical follow-up in 26 patients. Giant cells were grouped into histiocytic or neoplastic ones and the latter subtyped according to morphologic and immunocytochemical characteristics. Neoplastic giant cells were found in 34.6% of all pure seminomas and in 11.2% of all combined tumors, i.e. twice as often as histiocytic giant cells in either tumor group. The various types of neoplastic giant cells were found alone or in combinations with other types. Giant cells capable of elaborating B-HCG were seen in 19.3% of all pure seminomas and in 9.3% of seminomatous components of combined tumors. These incidences argue strongly against a trophoblastic element infiltrating a seminoma from a concomitant occult choriocarcinomatous focus. Large mononuclear giant cells, seen in spermatocytic seminomas, were observed in 15.6% of all pure seminomas, particularly in combination with B-HCG producing giant cells. Another type, characterized by marginated nuclei and eosinophilic cytoplasm were invariably part of a mononuclear cell population of similar features and encountered focally in 9.1% of all pure seminomas. Clinical follow-up, particularly in cases with B-HCG positive giant cells, revealed that treatment as for conventional seminomas at an early stage at least is followed by an excellent course.