Often present as testicular lumps.
Broadly categorised into germ cell tumours and non-germ cell tumours. Within the germ cell tumours, there are 2 classification systems.
Germ cell tumours
Thought to derive from a common precursor lesion known as intratubular germ cell neoplasia - undifferentiated (IGCNU). This precursor lesion was first described as 'carcinoma in situ' in 1978.
Divided into seminomas and non-seminomas.
2 classification systems: the 2004 WHO classification and the British Testicular Tumour Panel (BTTP) classification.
The latter is used mainly in the UK and Ireland, whilst the WHO classification is more international and has less cumbersome and less confusing labels. Whereas the term 'teratoma' is used in several BTTP entities, it has a more restricted use in the WHO classification. The WHO classification included malignant teratoma - immature, which was abbreviated to MTI and was a potential source of confusion with the BTTP MTI which stood for malignant teratoma - intermediate. The WHO classification is used below with the BTTP equivalents in braces.
- Choriocarcinoma (Malignant teratoma - trophoblastic)
- Embryonal carcinoma (Malignant teratoma - undifferentiated)
- Teratoma (Teratoma - differentiated)
- Yolk sac tumour (Yolk sac tumour)
- Mixtures of the above are termed mixed germ cell tumours (Malignant teratoma - intermediate)
Non-germ cell tumours
- Malignant lymphoma
- Interstitial cell tumour or Leydig cell tumour.
- Sertoli cell tumour
- Adenomatoid tumour
- Paratesticular sarcoma
- ↑ Skakkebaek NE. Carcinoma in situ of the testis: frequency and relationship to invasive germ cell tumours in infertile men. Histopathology. 1978 May; 2(3):157-70.
- ↑ Berney DM. Staging and classification of testicular tumours: pitfalls from macroscopy to diagnosis. Journal of clinical pathology. 2008 Jan; 61(1):20-4.(Link to article – subscription may be required.)