Histological grading of an immature teratoma of the ovary is based on which finding?

• A Proportion of yolk sac elements present
• B Number of mitoses in mature cartilage
• C Quantity of immature neuroectodermal tissue per slide ✓
• D Degree of nuclear atypia in the squamous epithelium

Explanation

Immature teratomas are graded 1 to 3 according to the amount of immature neuroectodermal tissue, assessed by counting low power fields containing primitive neural elements. Grade correlates with risk of extraovarian spread and recurrence and guides use of adjuvant chemotherapy in higher grades. Mature cartilage mitoses, squamous atypia and yolk sac proportions do not define the grade; a yolk sac component would instead reclassify the lesion as a mixed germ cell tumour.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.