Testicular germ cell tumors. Classification based on fine needle aspiration biopsy

Fine needle aspiration (FNA) biopsy was performed preoperatively on 13 patients with testicular germ cell tumors. The cytologic typing of the tumors was based on the presence or absence of seminoma, embryonal carcinoma, yolk-sac tumor, choriocarcinoma and teratoma in the aspirate. The cytologic findings showed good agreement with the histologic findings. Only four cases showed a single type of tumor; the other nine cases showed as many as four different tumor components. A few characteristic cytologic features proved to be sufficient for tumor typing; this suggests that FNA biopsy cytology can also be useful in identifying metastatic germ cell tumors in extra-gonadal sites.     

Testicular tumors in carp-funa hybrid: annual cycle and effect on a wild population

This study documents the occurrence of testicular tumors in a wild population of carp-funa hybrids. The most prevalent tumor was a dysgerminoma. There were lower prevalences of seminomas, leiomyomas, Sertoli cell tumors, and spermatocytic seminomas. Sex-ratio, gonadosomic index (Gi) and the prevalence of tumors in the monthly catch was analysed for five consecutive reproduction periods (1980 to 1984). Gonadal tumors were found only in males. This may be important to the population dynamics of the carp-funa hybrid, since a high percentage of the fish that die during spawning have these tumors. A schematic model for the reservoir's population is suggested.     

Testicular aromatase

The cytochrome P450 aromatase (P450arom) is the terminal enzyme involved in the irreversible transformation of androgens into estrogens. The P450arom plays a role in development, reproduction, sexual differentiation and behaviour, but also in bone and lipid metabolisms, brain functions and diseases such as breast and testicular tumors. Besides testicular somatic cells, where the aromatase gene is expressed via promoter II and I.4, this gene is transduced in a fully active protein in rat germ cells providing evidences for an additional site of estrogen production within the male gonad of rodents (our results and these in the literature). In addition we provided evidence for the expression of P450arom in ejaculated human spermatozoa. Together with the widespread distribution of estrogen receptors (ER alpha and ER beta) in various testicular cells as well as in the other parts of the genital tract, these data suggest a physiological role for these female hormones in the regulation of spermatogenesis especially in the postmeiotic steps.     

Testicular dysgenesis syndrome

In the Western world fertility rates are low and infertility is a major health problem. Unofficial statistics from Denmark reveal that about 6% of all Danish children are now born after assisted reproduction techniques, including in vitro fertilization, intracytoplasmic sperm injection, donor insemination or homologous insemination. However, there are no retrospective data on trends in fecundity (ability to conceive). We, and others, have focused on some aspects of adverse trends in male reproductive health such as the rising incidence of testicular cancer, low and probably declining semen quality, high and possibly increasing frequencies of undescended testes and hypospadias. Due to medical specialization and the different ages at presentation of symptoms, reproductive problems used to be analysed separately by various professional groups, for instance paediatric endocrinologists, urologists, andrologists or oncologists. There is evidence that poor semen quality, testicular cancer, undescended testes and hypospadias are symptoms of one underlying entity, testicular dysgenesis syndrome (TDS), which may be increasingly common due to adverse environmental influences. Experimental and epidemiological studies suggest that TDS is the result of disruption of embryonal programming and gonadal development during fetal life. An endocrine disrupter hypothesis to explain the adverse trends has been proposed. It is recommended that future epidemiological studies on trends in male reproductive health should not focus on one symptom alone, but be more comprehensive and take all aspects of TDS into account.     

Testicular development in Brahman bulls

Brahman breed bulls (Bos indicus) are widely used to introduce environmental resistance traits into meat-producing herds. However, their reproductive development is slower than European breeds (Bos taurus). The objective of this study was to assess the development of the seminiferous epithelium in Brahman bulls. Twenty-three prepubertal bulls were castrated and testicular samples taken for histological processing. Light microscopic images were digitized and cells of the seminiferous epithelium were assessed. Immature Sertoli cells gradually decreased in numbers and were no longer detected after approximately 14 months of age; concurrently, the numbers of mature Sertoli cells increased from 10 to 14 months. Spermatogenesis started during the ninth month; prior to that, only gonocytes and immature Sertoli cells were observed. Type A spermatogonia, spermatocytes, round spermatids, elongated spermatids and spermatozoa were first detected at 9.5, 11, 11, 13 and 16 months of age, respectively. The delay in the onset of puberty in Brahman bulls with respect to B. taurus was attributed to a longer duration of the prepubertal period (interval from start of spermatogenesis to puberty) and a later start of spermatogenesis.     

Testicular involution following optic enucleation

Summary The testes of adult male Syrian hamsters underwent involution within six weeks after optic enucleation. The diameter of the seminiferous tubules was 39% less than controls. Sertoli cells, spermatogonia, and primary spermatocytes were still present, but all steps of spermatids were completely absent from the involuted testes. Lipid droplets filled the Sertoli cell cytoplasm and often encroached upon the nucleus. Sertoli cells had sparse mitochondria and smooth endoplasmic reticulum, but Golgi cisternae were abundant. Typical SertoliSertoli junctions attached contiguous Sertoli cells. With lanthanum tracers it was demonstrated that these junctions were impenetrable; therefore, the bloodtestis barrier was deemed intact. Irregularly shaped protrusions often arose from the peritubular tissue and extended inward toward the seminiferous epithelium, often displacing the cytoplasm of the Sertoli cells and spermatogonia. The core of these protrusions consisted of irregular extensions of myoid cell cytoplasm surrounded by the myoid cells' basal lamina. External to the myoid cell basal lamina were bundles of collagen filaments with the basal lamina of the seminiferous epithelium forming the outermost layer of these protrusions. The apices of the Sertoli cells gave rise to numerous leaf-like processes that extended into and obliterated the lumen of the tubules. The Sertoli cell basal cytoplasm often contained phagocytized degenerating germ cells that appeared to give rise to the lipid droplets that filled the Sertoli cell cytoplasm. Acid phosphatase rich lysosome-like organelles were seen fusing with the degenerating germ cells and lipid droplets. The degenerating germ cells also were shown to contain acid phosphatase activity.     

Testicular chromosomes of Gallus domesticus

Summary Testes of Gallus domesticus were studied (a) by light microscopy after hypotonic treatment followed by acetic-alcohol fixation and airdrying and (b) by electron microscopy of osmium-fixed, araldite-embedded material, some of which was pretreated with hypotonic solutions.The following conclusions were reached: (i) The number of chromosome pairs at meiosis is constant and is most probably 40 (although 39 or 38 is possible). (ii) The diploid chromosome number at mitotic metaphase cannot be certainly determined by light microscopy but there is no reason to suppose it is not double the number of meiotic bivalents. (iii) No essential difference in structure was found between long and short bivalents at meiosis by light or electron microscopy; the lengths of the bivalents at pachytene form a continuous series, (iv) Some short bivalents appear to contain less material per unit length than long ones; this could explain why these chromosomes cannot always be resolved by light microscopy when fully contracted. (v) So-called macro- and micro-chromosomes differ only in size, but not in behaviour, at mitosis and meiosis.     

Testicular function in Klinefelter syndrome

Klinefelter syndrome (KS) is the most common genetic form of male hypogonadism, but the phenotype becomes evident only after puberty. During childhood, and even during early puberty, pituitary-gonadal function in 47,XXY subjects is relatively normal, but from midpuberty onwards, FSH and LH levels increase to hypergonadotropic levels, inhibin B decreases to undetectable levels, and testosterone after an initial increase levels off at a low or low-normal level. Hence, most adult KS males display a clear hypergonadotropism with a varying degree of androgen deficiency; subsequently, testosterone substitution therapy is widely used to prevent symptoms and sequels of androgen deficiency. Testicular biopsies of prepubertal KS boys have shown preservation of seminiferous tubules with reduced numbers of germ cells, but Sertoli and Leydig cells have appeared normal. The testes in the adult KS male are, however, characterized by extensive fibrosis and hyalinization of the seminiferous tubules, and hyperplasia of the interstitium, but the tubules may show residual foci of spermatogenesis. Introduction of testicular sperm extraction in combination with intracytoplasmic sperm injection techniques has allowed non-mosaic KS males to father children.