Germ cell tumor classification

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  • Ovarian germ cell tumors (OGCTs ): The histologic types that arise from the ovary are similar to those arising from the testes of men
    • Embryo-like neoplasms
      • Teratomas and their subtypes and
      • Dysgerminomas
    • Extraembryonic fetal-derived (placenta-like) cell populations
      • Yolk sac/primitiveplacenta forms (epithelial neoplasms differentiate into yolk sac tumors)
      • Mixed germ cell tumors (teratoma with yolk sac, dysgerminoma, and/or embryonal carcinoma) ●Rare OGCTs – Pure embryonal carcinomas, nongestational choriocarcinomas, and pure polyembryoma.
    • A mixture of both.
  • Extragonadal germ cell tumors (GCTs): no evidence of a primary tumor in the testes or ovaries
    • Typically arise in midline locations,
    • Specific sites vary with age
    • The most common sites in order of frequency
    • In adults:
      • Anterior mediastinum
        • Mature teratomas
        • Immature teratoma
        • Mediastinal seminoma
        • Mediastinal nonseminomatous GCT:
          • Yolk sac tumor (most common, pure or mixed)
          • Choriocarcinoma (less common)
          • Embryonal carcinoma (infrequent)
          • Mixed GCTs (a mixture of teratoma, seminoma, and other cell types)
      • Retroperitoneum
        • Retroperitoneal seminoma
        • Retroperitoneal nonseminomatous GCTs (Embryonal carcinoma is common)
        • Retroperitoneal teratomas (rare)
      • Pineal and suprasellar regions
    • In infants and young children:
      • Sacrococcygeal
      • Intracranial GCTs








Types Subtypes Signs and Symptoms Histopathology Lab finding Treatment Prognosis
Gonadal

Seminoma (Testis)

Gross: pale gray to yellow nodules that are uniform or slightly lobulated and often bulge from the cut surface
  • Complete blood count and blood chemistry tests.
  • Abnormal serum tumor marker levels (LDH, HCG).[1]
  • CT: Metastases to the para-aortic, inguinal, or iliac lymph nodes. Visceral metastasis may also be seen.
  • Pelvic MRI: may be diagnostic. multinodular tumors of uniform signal intensity
  • Hypo- to isointense on T2-weighted images and inhomogenous enhancement on contrast enhanced T1-weighted images.
  • Other diagnostic studies for seminoma include biopsy, FDG-PET scan, and bone scan.

Dysgerminoma

(Ovarian germ cell tumor)

  • Chemotherapy: except those with stage 1a, stage 1a, 1b dysgerminoma
  • Radiotherapy:


** Dysgerminoma is radiosensitive.

** Radiotherapy is not anymore the first option of treatment for dysgerminoma considering its association with ovarian failuredevelopment.

  • Surgery: for diagnostic grading and therapy depending on if the patient prefers to preserve the ovary or not.


Germinoma (Brain)

Extragonadal Embryonic

Teratoma

  • AFP
  • MSAFP
  • CT scans are often used to diagnose teratoma.


  • For malignant teratomas, usually, surgery is followed by chemotherapy.
  • Teratomas that are in surgically inaccessible locations, or are very complex, or are likely to be malignant (due to late discovery and/or treatment) sometimes are treated first with chemotherapy.


The prognosis of teratoma depends on the following:

  • Whether or not the tumor can be removed by surgery.
  • The size and location of the tumor
  • The patient’s general health
  • Teratomas are not dangerous for the fetus unless there is either a mass effect or a large amount of blood flow through the tumor (known as vascular steal). The mass effect frequently consists of obstruction of normal passage of fluids from surrounding organs. The vascular steal can place a strain on the growing heart of the fetus, even resulting in heart failure, and thus must be monitored by fetal echocardiography. After surgery, there is a risk of regrowth in place, or in nearby organs [1]

Extraembryonic

Coriocarcinoma

Yolk sac tumor