HYDATIDIFORM MOLE

‘Hydatidiform’ means a drop of water & a mole mean shapeless masses. It is defined as abnormal placenta characterize by –

• Enlarged, oedematous, chorionic villi which become vesicular
• Trophoblastic proliferations

It may be non-invasive or invasive 2 forms are in non-invasive type-

1. Complete (classic mole)- it is derived from the father (androgenesis) has a chromosomal pattern of 46XX.
2. Partial mole is mostly triploid 69XXY.

(1.) Non-invasive Mole-

-Clinically condition appears in the 4-5 months of gestation, characterized by increased in uterine size, vaginal bleeding & history of the passage of grape-like masses per vaginam.

-Serial determination of β-hCG is elevated more in blood & urine as compared with the level in normal pregnancy.

-Pathological find in noninvasive & in invasive is different.

(a) Classic mole-

Grossly- it is enlarged, filled with grape-like vesicles up to 3 cm in diameter & vesicles contain clear water fluid.

Microscopically- large, round, oedematous villi with decreased vascularity, Trophoblastic proliferation in the form of masses.

(b) Partial Mole-

Grossly- the uterus is smaller than expected, but part of the placenta appears normal and the fetus is having multiple malformations.

Microscopically- some of the villi show oedematous change while others are normal. Trophoblastic proliferation is usually slight.

(2.) Invasive Mole-

Grossly- invasive mole shows the invasion of tissues into the uterine wall which causes hemorrhage.

Microscopically- usually lesion is benign & identical to classic mole, there is an elevated β hCG level.