Uterine Pathology Flashcards
What is endometriosis?
Ectopic endometrial tissue elsewhere in the body e.g. in pelvis
Epidemiology of endometriosis?
6-10% of women aged 30-40 years
Now thought 1 in 10 women of reproductive age suffer from it
Aetiology of endometriosis?
unknown but regurgitation theory/metaplasia theory/ stem cell theory/ metastasis theory
What is the ‘regurgitation theory’?
Menstrual flow backs up through fallopian tubes, with subsequent implantation of endometrial tissue in the peritoneum.
What is the metaplasia theory?
The metaplastic theory suggests that pelvic endometriosis may be derived through the metaplastic transformation of peritoneal mesothelium. Endometriosis may manifest as a serial change from the adjacent mesothelial cells.
What is the stem cell theory for endometriosis?
The stem cell theory suggests that the stem cells in the uterus may be able to migrate outside of the uterus where they can form endometrial-like tissue.
Pathogenesis of endometriosis?
i.e. how does it lead to fibrosis?
Each month these ectopic foci react in the same way to endometrium in the uterus, building up and then breaking down and bleeding. However, this blood has no way to escape leading to pain/inflammation/scarring/cyst formation or nodules. I.e. bleeding into tissues –> fibrosis
Clinical features of endometriosis?
o 25% asymptomatic o Dysmenorrhoea o Dyspareunia o Pelvic pain, pain during intercourse o Subfertility o Pain on passing stool o Dysuria
Treatment for endometriosis?
- NSAIDs are first-line, with progesterone-only or combined contraceptive pills.
- Disease recurrence is common.
- Surgical ablation of lesions is the definitive treatment.
Gold standard for diagnosis of endometriosis?
laparoscopy and biopsy
What are endometrial polyps?
Localised overgrowth of endometrial tissue that projects into the uterine cavity and is attached by a pedicle. Can be single or multiple.
Endometrial polyps can be either sessile or pedunculated. What does this mean?
Sessile - broad based
Pedunculated - on a narrow stalk
Epidemiology of endometrial polyps?
<10% of women aged 40 – 50 years
How does the incidence of endometrial polyps change with age?
The incidence of polyps rises steadily with increasing age and it varies according to population studied, but about one in ten women will have a polyp in their lifetime.
Aetiology of endometrial polyps?
unknown
Proposed that they arise as the inappropriate reaction of foci of endometrium to oestrogenic stimulation
Clinical features of endometrial polyps?
o Often asymptomatic
o Intermenstrual/post-menopausal bleeding
o Menorrhagia
o Dysmenorrhoea
Investigations for endometrial polyps?
o Ultrasound
o Hysteroscopy
Are endometrial polyps benign?
- Almost all polyps are benign (malignant changes reported in <1% of polyps)
- The risk of malignancy in polyps increases with age and carries a risk of 2.3% in symptomatic postmenopausal women (0.3% if asymptomatic)
How many layers does the uterus have? What are they?
3:
- Outer perimetrium/serosa
- Middle myometrium (smooth muscle layer)
- Inner endometrium
What are the 4 parts of the uterus?
- Fundus
- Body
- Isthmus
- Cervix
The endometrium itself is divided into 2 layers. What are they?
- Stratum functionalis
2. Stratum basalis
What is the stratum functionalis of the endometrium made up of?
Made up of glands and supporting connective tissue, called stroma
How is the stratum functionalis of the endometrium affected during the menstrual cycle?
During the menstrual cycle, this layer expands and vascularises and is subsequently sloughed off during menstruation (i.e. functional)
How is the stratum basalis affected during the menstrual cycle?
This layer stays relatively constant
Regenerates the overlying functional layer after each menstrual cycle
What is the growth of the functional layer of the endometrium regulated by?
Hormones secreted by the ovaries –> Oestrogen stimulates the growth of endometrial glands and stroma.
What does each ovary consist of?
Each ovary is made up of a number of ovarian follicles:
Each follicle consists of an oocyte (female germ cell) surrounded by theca cels and granulosa cells
REVISE THIS!! (IMS/Body Systems?)
Function of theca cells and granulosa cells?
Oestrogen synthesis:
- Theca cells produce androgens in response to LH.
- Granulosa cells respond to FSH mainly by synthesising androgens to oestrogens
Effect of oestrogen on the uterus?
Oestrogen stimulates the growth of endometrial glands and stroma of the endometrium
What part of the menstrual cycle does oestrogen dominate?
First phase of the menstrual cycle
What is the first phase of the menstrual cycle called?
Proliferative phase (follicular phase) because it’s when the lining of the endometrium grows (proliferates).
At the end of the follicular phase of the menstrual cycle, what happens?
Ovulation occurs due to LH surge from the pituitary:
o One ovarian follicle expels the oocyte into the fallopian tube and it travels to the uterus.
o Follicle then collapses to form a corpus luteum
What is the 2nd phase of the menstrual cycle called?
Luteal phase / secretory phase
What is the corpus luteum responsible for?
Progesterone production in luteal phase
What are the effects of progesterone in the luteal phase of the menstrual cycle?
o Counteracts the effect of oestrogen on the endometrium by preventing further proliferation.
• At the same time, it causes the glands to produce secretions that acts as nutrients for any developing embryo
What is endometrial hyperplasia?
Hyperplasia of the endometrium that most often results when the endometrium is exposed to high levels of oestrogen for a prolonged time (and low levels of progesterone).
What are the effects of the endometrium being exposed to oestrogen for a prolonged time?
o This leads to excessive growth of endometrial glands relative to stroma; meaning a high gland-to-stroma ratio.
o This is also accompanied by low levels of progesterone, which (as mentioned previously) normally has an opposing effect to oestrogen
Epidemiology of endometrial hyperplasia?
> 40 years 3 times more incidence than endometrial cancer