Benign and Malignant Tumors of the Female Reproductive System Flashcards
Role of HPV E6 and E7
Gestational trophoblastic disease
- Group of benign disorders of abnormal trophoblastic proliferation
- Lesions arise from fetal tisue (trophoblast!) rather than maternal tissue
- Includes hydatidiform moles/molar pregnancies and placental site nodules
Molar pregnancy
- Form of gestational trophoblastic disease caused by polyspermy
- Benign, but has a risk for transformaton into malignant lesion (gestational trophoblastic neoplasia)
- Looks like a bubbly mass that may occupy the entire uterus (complete) or only part with a present fetus (partial)
- Often causes hyperthyroidism due to the excessive amount of beta hCG, which can act at TSH receptors to stimulate T4 production
Gestational trophoblastic neoplasia
- Group of malignant trophoblastic proliferation disorders
- Includes invasive moles, choriocarcinoma, placental site trophoblastic tumor, epithelioid trophoblastic tumor
ZP3 receptor
ZP for zona pellucida
Expressed on the surface of the zona pellucida of an egg and binds to the head of a sperm cell, triggering the release of acrosin from the sperm and initiating the acrosome reaction
Partial molar pregnancy
- Dispermy -> 69 xxy, xxx, or xyy -> partial molar pregnancy
- Ultrasound shows hydropic placenta and a fetus, however the fetus is nonviable
- Histology shows a mixture of normal villi and hydropic villi, as well as exaggerated implantation site trophoblasts. There will also be trophoblastic proliferation between the villi.
- 1-5% risk of malignant trophoblastic lesion progression
Mechanisms of preventing polyspermia
- Depolarization of the membrane during the acrosome reaction due to opening of sodium channels (short term effect)
- Cortical reaction: calcium let in by the hole made by the sperm causes release of granule contents at the rim of the oocyte. Carbohydrates from these granules are attached to the outer rim of the zona pellucida, forming a physical barrier to sperm.
Complete molar pregnancy
- Egg contains no genetic material -> sperm duplicates its own DNA after meiosis (called androgenesis) -> usually 46, XX -> complete molar pregnancy
- Both sets of chromosomes are paternal
- Described as “clear vesicles” or “cluster of grapes”
- “Snowstorm” pattern is typical, often with large “Lutein” cysts present on ovaries due to prolonged, high-level hCG stimulation
- Histologically, enlarged hydropic villi with central cisterns
- 15-20% risk of maligiant trophoblastic lesion progression
Placentas in molar pregnancy are often described as. . .
. . . “hydropic” due to the cystic lesions
Treatment for complete molar pregnancy
Suction dilation and curettage both confirms the diagnosis and is optimal therapy.
Follow procedure with serial beta hCG levels weekly. Once normalized, continue monitoring with monthly beta hCG levels.
GTN is usually diagnosed by. . .
. . . elevated beta hCG levels and a consistent clinical picture with supportive imaging findings
Histology is NOT taken as part of diagnosis, but will be pathologically analyzed as part of therapeutic excision to retroactively confirm the diagnosis
Evaluation for metastatic gestational trophoblastic neoplasia
- Pelvic ultrasound and chest x-ray are first steps
- If seen on the above, CT abdomen/pelvis and brain MRI are performed
Why should GTN never be biopsied?
Because it is SO HIGHLY VASCULAR
The patient will bleed out.
Treatment of GTN
- Disease confined to uterus: Hysterectomy
- Otherwise: Chemotherapy
- Brain involvement: Radiation therapy
HPV strains that cause genital warts
HPV6, HPV11
HPV strains that cause cervical epithelial neoplasia
- HPV 16, 18
- HPV 31, 33, 35, 39 (all 3x odd but 37)
- HPV 51, 52
Koilocytes
Cervical epithelial cells with nuclear enlargement and a “halo”
Sign of low-grade HPV infection
CIN grading system
In other words, if p16 is positive, it is considered a high grade lesion
CIN grading diagram
Note that the principle factor is thickness of the neoplastic cell region relative to the height of the epithelium, with “high-grade” being >2/3 of the epithelium replaced with neoplastic cells
HPV-derived squamous cell carcinoma histology
LFIL or CIN1 will likely. . .
. . . resolve on its own. So, we just need to check again in 1 year to ensure that it has.
The mechanism here is that, in CIN1, HPV has usually not integrated into the genome, so it is unlikely to persist.
What is going on in this cervical histology?
Adenocarcinoma in situ
Also usually driven by HPV 16 and 18
___ is a risk factor for more severe CIN
Smoking is a risk factor for more severe CIN
This is somewhat counterintiutive, since it is a virally driven process, but data shows that smokers are more likely to have severe CIN independent of other risk factors.
The HPV vaccine contains . . .
. . . L1 capsid proteins from various HPV strains
Layers of the endometrium
Proliferative and secretory endometrium cycling
Endometrial biopsy is recommended for women over the age of __ with abnormal uterine bleeding.
Endometrial biopsy is recommended for women over the age of 45 with abnormal uterine bleeding.
It is also recommended in women younger than 45 if there are risk factors for endometrial cancer (obesity, chronic anovulation)
What causes benign endometrial hyperplasia?
Estrogen signaling unopposed by progestins
What is going on in this endometrial biopsy?
What are the major risk factors for endometrial hyperplasia?
It’s all about unopposed estrogen signaling
PCOS: Chronic anovulation due to low FSH -> no corpus luteum -> no progesterome -> unopposed estrogen signaling
Obesity: Increased number of adipocytes -> adipocytes express aromatase -> converts androstenedione to estrone -> estrone converted to estradiol -> increased estrogen:progesterone ratio
Also tamoxifen therapy, nulliparity, early menarche, late menopause
How do you treat benign endometrial hyperplasia?
Lower the estrogen, raise the progesterone!
Progestin contraceptives highly effective.
What is going on in this endometrial biopsy?
Endometrial intraepithelial neoplasia
Note that in this biopsy there is one normal gland in the top left corner for comparison. Its epithelia are much smaller than all of the others.