Placental pathology

Question 1

Tenney-Parker change - define.
Histological findings.
Causes.

Answer 1

Increased numbers of trophoblastic syncytial knots, often due to maternal hypertension or uteroplacental insufficiency
Histo: terminal villous hypoplasia.

Question 2

32F. Endometrial currettings for HMB

Dx?
What is it?
ddx?
IHC?

Answer 2

Placental site nodule.
Foci of persistent intermediate trophoblasts and extracellular matrix remaining after pregnancy. Usu microscopic incidental finding.
Histo: Round to oval lobulated margins, central hyalinized core. Trophoblast cells dispersed as single cells, clusters or cords with eosinophilic,hyalinized extracellular matrix. Minimal pleomorphism, mitotic activity, Ki67< 5%
DDx: Atypical placental site nodule (larger focus if persistent, chorionic-type IT with increased cellularity, more cohesion of IT, mild nuclear atypia, and increased Ki67 labeling c/p to PSN).
IHC: Placental alkaline phosphatase (PLAP) - strongly stains trophoblast cells.

Question 3

25F, G2 P1 E1 presents with vaginal bleeding.

Question 4

Describe the role of p57 in diagnosing molar prengnacies?

Answer 4

p57 is a cyclin dependent kinase inhibitor protein, the product of the paternally imprinted, maternally expressed gene CDKN1C (p57KIP2) located on chromosome 11p15.5

p57 immunohistochemical stain can be used to separate a complete hydatidiform mole from partial hydatidiform mole and nonmolar gestations

Normal p57 expression (strong nuclear staining in villous cytotrophoblasts, intermediate trophoblasts and villous stromal cells) is seen in all gestations that contain maternal genetic material. p57 expression is lost in complete hydatidiform mole, while it is retained in partial hydatidiform moles and nonmolar specimens. p57 immunohistochemistry cannot distinguish between a partial hydatidiform mole and nonmolar gestations. Complete hydatidiform moles (CHM), including very early complete moles, lack maternal genetic contribution, therefore p57 expression is typically absent in villous and stromal cytotrophoblasts.

Question 5

Difference in cell lineage in placental site trophoblastic tumour and epithelioid trophoblastic tumour.

Answer 5

PSTT: implantation site intermediate trophoblasts.
ETT: chorionic-type intermediate trophoblasts.

Question 6

30F h/o IUFD at 23/40 placenta

Key feature demonstrated

Answer 6

Parvovirus B19 infection

Villous edema associated with hydrops
Ground-glass eosinophilic nuclear inclusions in nucleated red blood cells within fetal capillaries (“lantern cells”)

The arrows demonstrate erythroid precursors with characteristic parvovirus inclusions in this placenta from a fetus infection with parvovirus B19

Question 7

layers of placental membranes

Answer 7

Question 8

placental inflammation

Name and describe the criteria used to grade and stage placental inflammation

Answer 8

Question 9

Chorangiosis

define:
Associations:

Answer 9

The presence of >/= 10 capillaries per terminal villus in 10 terminal villi in a tleast three different regiosn of hte placenta.

Associated with congenital anomalies, maternal diabetes, maternal anaemia, smoking, twin gestations, and delivery at high altitiude.