Complete hydatidiform mole is distinguished from partial hydatidiform mole by which combination of histological and cytogenetic features?

• A Complete mole: 69,XXX or 69,XXY karyotype; diffuse trophoblastic hyperplasia; fetal/embryonic tissue absent
• B Complete mole: 46,XX or 46,XY (androgenetic diploid); diffuse trophoblastic hyperplasia; fetal tissue absent ✓
• C Partial mole: 46,XY androgenetic; focal trophoblastic hyperplasia; fetal tissue present
• D Complete mole: 46,XX biparental; focal trophoblastic hyperplasia; fetal tissue present

Explanation

Complete mole is androgenetic diploid (46,XX most commonly, or 46,XY) — arising from fertilisation of an anucleate egg by one (then duplicated) or two sperm; no maternal DNA. Histology shows diffuse circumferential trophoblastic hyperplasia, cistern formation, and absence of fetal/embryonic tissue. Partial mole is triploid (69,XXX or 69,XXY, rarely 69,XYY) — fertilisation of a normal egg by two sperm; focal trophoblastic hyperplasia and fetal tissue are present.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.