Non-seminomatous germ cell tumors

2023-04-24   Andres M. Acosta, MD 

1.Department of Pathology, Indiana University, Indianapolis, IN

Classification

Definition

Non-seminomatous germ cell tumors (NSGCTs) comprise neoplasms with pure non-seminoma histology, as well as mixed tumors (which may include a component of seminoma). Among NSGCTs, mixed tumors are more frequent than pure tumors (~70% versus ~30%). The different histologic types of NSGCTs include embryonal carcinoma, post-pubertal yolk sac tumor (YSTs), post-pubertal teratoma, and trophoblastic neoplasms (the most frequent being choriocarcinoma). 

Non-seminomatous germ cell tumorsGenetic Event(s)
Embryonal carcinoma (EC)Genomic findings are overall similar in seminoma and non-seminomatous germ cell tumors (GCTs). However, there are some differences including a slightly lower mdeian ploidy (~2.8 versuss ~3.1) and different patterns of recurrent losses of chromosomal arms. 1 Unlike pure seminomas, nonseminomas invariably harbor gains of sequences of 12p and/or i(12p) but KIT, KRAS and NRAS mutations are relatively rare. 1 The rpocesses that drive the reprogramming of non-seminomatous GCTs are though to be driven largely by epigenetic mechanisms. 2 Like seminoma, embryonal carcinoma expresses miR-371-3p. 1,3
Yolk sac tumour (YST), postpubertal-typeYolk sac tumor postubertal type (YST) is expected to have a lower median ploidy and different patterns of recurrent chromosomal losses than seminomas. 1 Unlike pure seminomas, YST, postpubertal type almost invariably harbor gains of sequences of 12p and/or i(12p). 1 The rpocesses that drive the reprogramming of non-seminomatous GCTs are though to be driven largely by epigenetic mechanisms. 2 YST, postpubertal type does not demonstrate significant expression of miR-371-3p 1,3.
ChoriocarcinomaChoriocarcinoma is expected to have a lower median ploidy and different patterns of recurrent chromosomal losses than seminomas. 1 Choriocarcinoma harbors gains of sequences of 12p and/or i(12p). 1 The rpocesses that drive the reprogramming of non-seminomatous GCTs are though to be driven largely by epigenetic mechanisms. 2 Chriocarcinoma is not expected to express miR-371-3p 1,3.
Placental site trophoblastic tumourNo specific genetic findings so far.
Epithelioid trophoblastic tumourNo specific genetic findings so far.
Cystic trophoblastic tumourNo specific genetic findings so far.
Teratoma, postpubertal-typeIt occurs in adults mainly as a component of a mixed germ cell tumor and most commonly after chemotherapy. Cystic trophoblastic tumor typically demonstrate overrepresentation of sequences of 12p/i(12p) .4
Teratoma with somatic-type malignancy"Somatic-type" malignancies associated with teratoma demonstrate gains of 12p/i(12p), distinct methylation profiles, a high degreee of aneuploidy and relatively frequent alteration of genes of the TP53 pathway. 5-8 So called "somatic-type" malignancies arising in teratoma are often resistant to cisplatin-based chemotherapy regimens. 9
Mixed germ cell tumors of the testisMixed germ cell tumors have molecular features similar to nonseminomas.
Regressed germ cell tumorsNo specific genetic findings so far.

Article Bibliography

Reference NumberPubmed IDLast YearTitleAuthors
1298984072018Integrated Molecular Characterization of Testicular Germ Cell Tumors.Shen H et al
2314133242019Human germ cell tumours from a developmental perspective.Oosterhuis JW et al
3331586612021Integrated Expression of Circulating miR375 and miR371 to Identify Teratoma and Active Germ Cell Malignancy Components in Malignant Germ Cell Tumors.Nappi L et al
4321445402020Histology, 12p status, and IMP3 expression separate subtypes in testicular teratomas.Semjén D et al
5151679392004Fluorescence in situ hybridization analysis of chromosome 12p in paraffin-embedded tissue is useful for establishing germ cell origin of metastatic tumors.Kernek KM et al
6314789412019Fluorescent In Situ Hybridization Analysis for 12p Alterations in Sarcomatoid Yolk Sac Tumors.Idrees MT et al
7354382032022Morphological spectrum and molecular features of somatic malignant transformation in germ cell tumours.Lobo J et al
8360302882022Molecular correlates of male germ cell tumors with overgrowth of components resembling somatic malignancies.Wyvekens N et al
9358034132022Somatic-type malignancies in testicular germ cell tumors.Guo CC et al

Citation

Andres M. Acosta, MD

Non-seminomatous germ cell tumors

Atlas Genet Cytogenet Oncol Haematol. 2023-04-24

Online version: http://atlasgeneticsoncology.org/solid-tumor/209117/non-seminomatous-germ-cell-tumors