1. a. Adenomatoid tumor is a common paratesticular tumor involving the epididymis, tunica, and, rarely, the spermatic cord. These tumors can be found in association with the uterus, fallopian tubes, ovaries, and retroperitoneum adjacent to the adrenal. Histologically, the tumor consists of fibrous stroma with varying amounts of smooth muscle and inflammatory infiltrate. The epithelial cells are mesothelial in origin and form solid strands or cords. The cytoplasm contains vacuoles, which often coalesce resulting in cystic spaces with a “spider web” appearance.

2. c. The upper limit of serum AFP is up to 9 µg/mL. The half-life is 4 to 5 days.

3. e. In this setting, there is a 30% chance of having retroperitoneal metastasis. In a mixed germ cell tumor with more than 40% of embryonal carcinoma and vascular or lymphatic invasion, the likelihood of stage II disease increases.

4. b. Yolk sac tumors account for up to 60% of germ cell tumors in infants and children.

5. b. Elevated serum levels of AFP are generally due to the presence of yolk sac tumor either in pure form or in association with other germ cell tumor types. AFP production is also seen in glandular or in hepatoid elements of teratoma. About 13% of embryonal carcinomas may show AFP production in isolated or small groups of tumor cells and are not associated with detectable serum level elevations. Seminoma is generally negative for this marker histologically and serologically.

6. a. The patient with cryptorchidism has a 3 to 5 times increased risk of developing testicular cancer. Therefore, the lifetime probability of developing a germ cell tumor is approximately 3.5% to 14%.

7. c. The patient has a 2% to 5% chance of having a contralateral tumor and has a more than 20-fold increased risk for tumor development compared with the general population. Intratubular germ cell neoplasia can be identified in about 5% to 6% in the contralateral testicular biopsy. It is important to teach patients about tes – ticular tumors to perform regular self-examination of the contralateral testis.

8. d. Ectopic HCG production can be seen in any malignancy, particularly carcinomas. Such tumors often have marked nuclear anaplasia. The ectopic HCG production can cause elevated serum levels of HCG. Other placental glycoproteins (e.g., human placental lactogen, PLAP, etc.) can also be identified in nongerm cell tumors.

9. a. Carney syndrome is a rare disorder characterized by mucocutaneous pigmentation, atrial myxoma, endocrine tumors (pituitary, adrenals), and large cellcalcifying Sertoli cell tumors. The latter are often bilateral and consist of large eosinophilic cells resembling Leydig cells. The cells form cords or tubules. The calcifications vary in extent. Some of these tumors are malignant.

10. e. Spermatocytic seminoma is a rare neoplasm comprising about 2% to 5% of testicular germ cell tumors. There is no correlation with cryptorchidism. It usually arises in older men around age 50 to 55 and has not been reported in prepubertal children or adolescents. It has not been reported in extratesticular sites, or in association with other germ cell tumors. Clinically, most patients present with painless swelling, which may be present for years. There are cases with bilateral synchronous or metachronous involvement. There are reported cases of spermatocytic seminoma with metastases. However, only one well-documented case is known. Spermatocytic seminoma is rarely associated with sarcoma; these tumors metastasize as sarcomas.

11. a. Papillary cystadenoma of epididymis is a benign tumor that accounts for about one third of all primary epididymal tumors. Mean age is 36 years. It often involves the head of the epididymis. About two thirds of papillary cystadenomas of the epididymis occur in patients with von Hippel-Lindau syndrome. In this setting, they are more frequently bilateral. The tumor consists of cuboidal to low columnar clear cells lining dilated ducts and papillae with a single- or a doublelayer epithelium. The tumors resemble clear cell renal cell carcinoma.

12. c. Sertoli cell tumors account for about 1% of all primary testicular tumors. They can occur at any age but are most common in the fourth to fifth decades (it ranges from 20-80 years old). There are several subtypes: Sertoli cell tumors not otherwise specified, largecell calcifying Sertoli cell tumor, sclerosing Sertoli cell tumor, lipid-rich Sertoli cell tumor, and the Sertoli cell tumor with heterologous elements. Sclerosing Sertoli cell tumors are not associated with hormonal symptoms. Grossly, the lesion is usually small (0.4-1.5 cm in diameter) and consists of solid, white to yellow-tan nodules. Microscopically, it is composed of cords, solid or hollow tubules, and nests of Sertoli cells set in a densely collagenous stroma. The nuclei vary from large to small, and the cytoplasm is pale and sometimes vacuolated. Immunohistochemically, vimentin and inhibin are present in the neoplastic cells. Pancytokeratin (AE1/3) may be focally positive. All the reported cases had a benign outcome.

13. c. Nodular periorchitis (fibrous pseudotumor, fibromatous periorchitis) of the tunica and paratesticular soft tissue typically arise as painless scrotal masses that may be associated with a hydrocele or history of trauma or infection. Typically, these masses are multinodular, but in rare cases they are diffuse, encasing the testis. Microscopically, they consist of collagen with calcifications and focal inflammatory cells.

14. a. This is a typical seminoma associated with varying numbers of large multinucleated giant cells with abundant pink cytoplasm. Often, the cytoplasm contains vacuoles, which may contain erythrocytes. The syncytiotrophoblastic cells are usually accompanied by hemorrhage. They can cause elevated serum levels of HCG depending on their number. This type of seminoma has the same prognosis as pure seminoma.

15. d. Teratomas are often cystic and consist of all three germinal layers (ectoderm, mesoderm and endoderm). The cysts are lined by various types of epithelium. Some are squamous with keratin-filled lumina, others are mucinous and resemble large bowel epithelium, or respiratory in type (pseudostratified and ciliated). Between the cysts are hair follicles, sweat and sebaceous glands, smooth muscle, and fat. All the tissues may be mature, immature, or both. Teratoma in the prepubertal child is diploid and benign. However, in the postpubertal male, teratomas (mature or immature) are commonly aneuploid and present with metastasis in about 30% to 40% at initial presentation. Therefore, teratomas in the adult male are not referred to as benign irrespective of their histologic appearance.

16. d. Although some areas consist of solid sheets of cells, much of the tumor is arranged in glandular and papillary structures. The cells are large and the nuclei tend to be irregular and variable in shape or contour. The cells of embryonal carcinoma differ from those of seminoma, chiefly in that cell borders are usually ill-defined, nuclei are vacuolated rather than stippled with fine chromatin granules, and the nuclei tend to be more irregular in shape compared with the rounded seminoma cell. The cells are larger than those of seminoma.

17. a. In Sertoli cell-only syndrome, seminiferous tubules are devoid of germ cells and are lined by thin palestaining Sertoli cells only (wind-swept appearance).

18. b. The tumor is located mainly in the interstitium. Note that the cells have very little cytoplasm in contrast to seminoma. The nuclei are irregular in shape and smaller than seminoma cells. The prostate biopsy also revealed lymphoma. Lymphomas of the testis may be the primary manifestation of this disease and are usually seen in men older than 50 years of age. Generalized lymphoma usually develops within 2 years, and bilateral testicular involvement is seen in about 25% of cases.

19. a.Macroscopically, the tumors consist of nodular excrescences studying the tunica with or without diffuse thickening of the tunica vaginalis and/or albuginea. Histologically, the mesothelial lining of the tunica is prominent and multilayered. The cells extend into the adjacent soft tissue as an epithelial-like tumor with solid areas, as well as tubules, acinar, and papillary structures. The cells generally contain abundant pink cytoplasm with nuclear pleomorphism. The lining mesothelial cells of the tunica are hyperchromatic, hyperplastic, and represent the site of origin of the neoplasm. Four months following surgery, tumor nodules recurred in the cord adjacent to the incision. Malignant mesothelioma of the tunica is often a manifestation of systemic disease involving peritoneal and/or pleural surfaces.

20. a.Microscopically, yolk sac tumors are variable and 10 subtypes are recognized. In most instances, several of these coexist. The glandular/alveolar pattern, microcystic, and micropapillary patterns are the most common. The neoplasm forms numerous glandular spaces, some of which are quite large, others minute. Some of the smaller glands resemble fat cells or endothelial-lined spaces, but these, in fact, are lined by flattened or cuboidal cells with clear or pink cytoplasm and irregular vesicular nuclei. There is also a papillary component. Some of these have a prominent central vascular core constituting the so-called glomeruloid structure referred to as the Schiller-Duval body (Fig. 11.12A).

21. c. In cryptorchid testis, the walls of the tubules have a hyalinized, thickened appearance. The tubules contain only Sertoli cells, recognized by their stringy, vacuolated cytoplasm and the fact that their nuclei have prominent nucleoli. The best evidence of cryptorchidism is the presence of small, tightly packed seminiferous tubules filled with immature Sertoli cells. In contrast to the Sertoli cells in the adjacent atrophic tubules, the immature Sertoli cells appear very dark with elongated hyperchromatic nuclei.

22. d. The section shows a large nodule of Leydig cells. It contains seminiferous tubules. The chief difference between Leydig cell hyperplasia and Leydig cell tumor is the presence of entrapped tubules seen in hyperplasia. The reason for the Leydig cell hyperplasia is not apparent.

23. d. The section shows the wall of a cyst composed of mature squamous epithelium, consistent with epidermoid cyst. The cyst contains keratin. The absence of skin appendages distinguishes this cyst from the dermoid cyst. This lesion is benign. The question if this tumor is a monophasic teratoma is still unsettled. Rare epidermoid cysts are associated with intratubular germ cell neoplasia, unclassified.