Case 39. Spermatocytic Tumor

Clinical case. A 59-year-old patient who presented with a 1-year-long painless progressive growth of the right testicle. He disclosed negative tumor markers (AFP, hCG, and LDH).

Pathological findings. In the orchiectomy specimen, the testicle measures 8 × 7 × 6.5 cm. The section was taken by a gray-white, lobular-shaped tumor with no hemorrhagic or necrotic areas, limited to the testicle. The surface was bright. In the peripheral areas, testicular parenchyma was recognized. Histologically, the arrangement of the cells is very varied, with prevalence of the sheet, pseudoglandular, cystic and follicular patterns, all of them with a common denominator, intense edema. No lymphoid infiltrates are observed. Three cell types are identified, lymphocyte-like cells by their hyperchromatic nucleus, medium-sized cells, and giant cells. In these last two cell types, chromatin has a filamentous appearance reminiscent of first-order spermatocytes. Many tubules with intratubular growth are observed. The number of mitoses is high. There is no infiltration of vessels or paratesticular structures.

Comments. The presence of three cell types in the same tumor associated with the characteristics of the chromatin of medium and large cells that resembles germ cell spiremas at the beginning of the first meiotic division, makes the diagnosis of the spermatocytic tumor very easy. Interesting facts in this case are the intense edema that determines the appearance of a macrocystic pattern and the formation of structures similar to thyroid follicles. Spermatocytic tumor is a tumor only seen in the testicle. Its incidence is 0.4 cases per million, 0.61% of all germ cell tumors. The age of presentation (53.5 years) is higher than that of the seminoma and has no greater incidence in cryptorchidic patients. About 6% of cases present sarcomatous transformation with rhabdomyosarcoma being the most frequent component. In these cases, the behavior is aggressive. Exceptionally, spermatocytic tumors, without a sarcomatous transformation, can metastasize. The immunohistochemical markers common in the studies of germ cell tumors (PLAP, AFP, podoplanin, CD30, OCT3/4) are negative. Markers such as GAGE7 and NY-ESO-1 may be more useful. The electron microscopy shows a distribution of chromatin that recalls the spiremas of the first-order spermatocytes.

Case 40. Anaplastic Variant of Spermatocytic Tumor

Clinical case. A 32-year-old patient who over 1 month had had progressive enlargement of the left testicle with discomfort but without fever. The ultrasound examination showed a very heterogeneous left testicle with multiple hyperechoic areas. The 3-cm in diameter epididymis head was also hyperechoic. Hydrocele was also observed but tumor markers were negative.

Pathological findings. A tumor consisting of several poorly defined whitish nodules with a tendency to be located in the upper pole of the testicle and the testicular mediastinum. The tumor infiltrates the albuginea and extends widely to the epididymis. The tumor cells are arranged in sheets. They constitute a relatively uniform population of medium-sized cells with a round nucleus having finely granular to filamentous chromatin. The nucleolus is larger in the larger cells that appear irregularly distributed among the others. The cytoplasm varies from clear to basophilic. The number of mitosis is high. No lymphoid infiltrates or epithelioid granulomas are observed. Areas of necrosis are frequent. The tumor cells are negative for PLAP, OCT3/4, CD30, and cytokeratins and positive for C-kit. In the vicinity of the tumor nodules, there are many tubules filled with tumor cells.

Comments. The tumor meets the characteristics of the so-called anaplastic variant of the spermatocytic tumor by some. It is characterized by the proliferation in sheets of medium-sized monomorphic cells. The other two cell types of these tumors are very rare or absent. This case adds another peculiarity, its aggressive behavior infiltrating paratesticular structures. A differential diagnosis could be considered with seminoma (does not express PLAP or OCT3/4), with embryonal carcinoma (does not express CD30 or cytokeratins) and with a lymphoma (absence of specific markers). It is a tumor, which, as in this case, appears at a younger age than the usual spermatocytic tumor. Less than a dozen cases have been published, one of them bilateral. Whether or not it is a variant with more aggressive behavior is a matter for discussion.

Case 41. Teratoma, Prepubertal-Type (Ectodermic and Endodermic Preferential Differentiation)

Clinical case. A 10-month-old boy with progressively growing right testicle over the last 3 months. The ultrasonography revealed intraparenchymatous cystic lesions with hyperechoic areas inside. The tumor markers were negative.

Pathological findings. The testicle size is 2.8 × 2.5 × 2.4 cm. The sectioned surface shows a cystic structure. Some of those cysts are larger than 1 cm. Some contain a serous material and others a sebaceous one. Histologically, the wall of the cysts is very varied: skin structures (epidermis and dermis with their annexes), digestive tube (mucosecretor epithelium and smooth muscle wall), respiratory (mucosa surrounded by cartilaginous nests), and even nerve tissue with choroidal plexuses. GCNIS is not observed in the peritumoral parenchyma.

Comments. This teratoma shows the most typical characteristics of teratoma, prepubertal-type: it derives from several blastodermal leaves, absence of immature tissues, an arrangement of tissues in an easily identifiable organoid pattern, and what is definitive, absence of GCNIS. However, it should not be forgotten that in older children and in pubertal patients, teratomas may be associated with GCNIS and, despite their age, postpubertal-type teratoma should be considered.

Case 42. Enterogenous Cyst of the Testis in a Child

Clinical case. A 6-year-old boy with a history of testicular trauma 3 years ago, in follow-up consultation due to increased size of the right testicle. The ultrasonography revealed that the testicle measured 30 × 15 mm and presented a nodular lesion that took two third of the testis, with hypoechoic areas. The head of the epididymis was heterogeneous with calcifications. Tumor markers (AFP, b-HCG, and lactate dehydrogenase) were within normal limits. Lumpectomy was performed.

Pathological findings. The orchiectomy specimen weighed 18 g. The external surface was irregular. The sectioned surface shows cystic formations with yellowish-green mucous material that replaces most of the testicular parenchyma. Histologically, the greater cavity is partially lined by an epithelium similar to that of the large intestine, both in the surface epithelium and in the glands, which even have Paneth cells. Beneath it, there is a poorly organized layer of smooth muscle cells. Other cystic formations lack lining epithelium, and both mucosa and other lymphoid cells are prominent in the interior and wall. The peritumoral parenchyma is compressed, presents spermatogonia, and lacks GCNIS.

Comments. The most prominent features of this tumor are its cystic aspect, the mucous content, the organoid pattern that forms a wall similar to that of the large intestine and the lack of atypia in all its components. At a first view, the organoid pattern, the patient’s age, and the absence of GCNIS would suggest a prepubertal-type teratoma. But there are some histological data that suggest that this is not a good diagnosis: the perfect organization of the larger cyst wall, the intestinal-type epithelium with glands surrounded by a layer with abundant smooth muscle cells. And, which is more important, there is absence of any derivative of another blastodermic leaf. These two facts rule out the diagnosis of teratoma and, on the other hand, suggest the diagnosis of an enterogenous cyst.

The reported enterogenous cysts are preferably located in the mediastinum, the peritoneal cavity, the spinal canal subarachnoid space, and the cerebral ventricle. So far, only one case has been reported in a child. The most accepted histogenesis that could explain the enterogenic cysts of other locations, the “Split notochord syndrome,” is difficult to apply to testicular enterogenic cysts. A good alternative is based on the embryology of the testicle. Primordial germ cells originate in the extraembryonic mesoderm in intimate relation with the wall of the yolk sac, and until they colonize the genital crests that develop in the 4th and 5th weeks they travel a long way through the dorsal mesentery. It could occur that at any moment of the development they dragged cells of the primitive intestine that would end up developing the enterogenic cyst.