Table 1 Histopathological features suggesting a malignant phenotype of a testicular Leydig cell tumour (Albers P, Albrecht W, Algaba F, Bokemeyer C, Cohn-Cedermark G, Fizazi K, Horwich A, Laguna MP, European Association of U [2011])

I.

Large Tumour size (>5 cm)

II.

Cytological atypia

III.

Increased mitotic activity (>3 per 10 high power field [HPF])

IV.

Increased MIB-1 expression

V.

Necrosis

VI.

Vascular invasion

VII.

Infiltrative margins

VIII.

Extension beyond the testicular parenchyma

IX.

DNA aneuploidy