Extragonadal germ cell tumors: A fine‐needle aspiration biopsy study

Abstract

Germ cell tumors (GCT) are neoplasms that originate predominately in the ovary and testis. Tumors of germ cell origin only very uncommonly arise in extragonadal sites. We have diagnosed ten primary malignant extragonadal GCT arising in the mediastinum, retroperitoneum, liver, and sacrococcygeal region by fine-needle aspiration biopsy (FNAB). Patient ages ranged from 1 to 54 years; the majority were males. Our series included three seminomas, three yolk sac tumors (YST), one choriocarcinoma, one embryonal carcinoma, and two mixed, poorly differentiated GCT. In aspirates, seminomatous elements are dissociated with uniform mononucleate cells having large vesicular nuclei and prominent nucleoli. A tigroid background is produced with Diff-Quik-stained smears. YST yields cohesive clusters of cells with large nuclei, vacuolated cytoplasm, and extracellular hyaline matrix (spheres or hyaline globules). Giant multinucleate tumor cells are seen in choriocarcinoma. Embryonal carcinoma yields cellular smears of hyperchromatic cells with scant cytoplasm arranged predominantly in glandular or papillary formations. Ultrastructural (four cases) and immunocytochemical (seven cases) studies of aspirated material corroborated our cytologic interpretations. Aneuploid tumor cells were found by flow cytometry in aspirated material from a YST. Subsequent histologic examinations were performed on eight, and all were confirmatory. Although extragonadal GCT are relatively uncommon, they need to be considered in FNAB material from midline mass lesions. Ancillary studies were useful in confirming their diagnosis.

Cytologic features of extragonadal germ cell tumors

“…An earlier study by Collins et al revealed similar findings in their case of EC. 17 In the presence of these cytologic features, metastatic adenocarcinoma has to be excluded. A clinical history of a gonadal GCT and measurement of serum tumor markers may be helpful in such cases, because the distinction on cellular features alone may be difficult.…”

Fine-Needle Aspiration Biopsy (FNAB) Diagnosis of Germ Cell Tumors: Histologic and Cytologic Correlations

“…[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] The cytoplasm is usually slightly granular and eosinophilic to light blue, but may also contain large "punched-out" vacuoles due to the presence of large aggregates of glycogen ( Figure 3). Periodic acid-Schiff (PAS) staining of smears may be used to confirm the presence of large amounts of intracytoplasmic glycogen (Figure 4).…”

“…The FNAB smears from embryonal carcinoma are usually cellular and are arranged in sheets and clusters which may show a solid, papillary or glandular pattern. [6][7][8][9][10][11][12][13][14] The tumor cells have ill-defined cell borders, high nuclear cytoplasm ratio and light basophilic granular cytoplasm ( Figure 6). The nuclei are irregular with coarse chromatin and usually contain multiple nucleoli.…”

“…A number of antibodies may be used for differentiating germ cell tumors from other non-germ cell tumors, such as malignant lymphoma and adenocarcinoma, and making precise distinction among the various subtypes of germ cell tumors. 13,16 These antibodies include leucocyte common antigen (LCA), cytokeratin (CK), placental alkaline phosphatase (PLAP), alpha-fetoprotéin (AFP), human chorionic gonadotropin (HCG), Leu MI and Ki-I (CD-30). The various patterns of staining in the different subtypes 5 of germ cell tumors are given in Table 3.…”

“…[6][7][8][9][10][11][12][13][14] Distinction of germ cell tumors from other types of neoplastic and non-neoplastic lesions, as well as distinction between the various subtypes of germ cell tumor, may have important therapeutic implications and may thus be crucial to planning proper management of the patient. When the germ cell tumors occur in the gonad, fine-needle aspiration is infrequently performed, since resection is usually indicated regardless of the underlying pathology.…”