Pathology of the Uterine Body and Endometrium

Question 1

Explain the development of the uterus

Answer 1

• At 6 weeks the coelomic lining of the epithelium forms the lateral Mullerian ducts. This grows downwards into the pelvis to fuse with urogenital sinus.
• The fused portion of the ducts for the uterus
• Unfused parts form fallopian tube.
• The endometrial cavity, linings of the fallopian tubes and peritoneal covering of all gynaecological organs are all derived from coelomic lining.

Question 2

Name some developmental abnormalities of the uterus

Answer 2

• Septate uterus,
• Bicornuate uterus,
• Unicornate uterus

Question 3

Describe the appearence of the endometrium in the proliferative phase

Answer 3

Oestrogen causes thickening of the endometrium and increased growth and motility of myometrium, thin alkaline cervical mucus is produced.
Histologically: Mitotic figures are present and glands are small, round and narrow.

Question 4

Describe the appearence of the endometrium in the secretory phase

Answer 4

Secretory phase: Progesterone stimulates further thickening of endometrium into a glandular secretory form. Thick acidic mucus is produce (to prevent polyspermy)
Histologically: Glands appear distended, plumper and more tortuous. They are secreting glycogen so pink glycogen is seen in the glands

Question 5

Describe the appearence of the endometrium in the menses

Answer 5

Menses: In the absence of fertilisation the corpus luteum breaks down and the internal lining of the endometrium is shed.
Histologically: Appears bloody with fragmented glands

Question 6

What is endometriosis?
Where are site of endometriosis?
What are the symptoms?

Answer 6

Presence of endometrial tissue outside of the uterus.
- Sites include: ovaries, peritoneal surfaces (inc uterine ligaments and rectovaginal septum), large and small bowel, appendix and mucosa of cervix, vagina, fallopian tubes and laparotomy scars.
- Presentation: Dysmenorrhoea, pelvic pain and infertility

Question 7

What is adenomyosis?

Answer 7

Presence of endometrial tissue within myometrium

Question 8

What are the two pathogenic mechanisms proposed for endometriosis

Answer 8

1. Metastatic theory - retrograde menstruation or surgical procedures introduce endometrium into sites out with endometrium.
2. Metaplastic theory - endometrium arises directly from coelomic epithelium of the pelvis. (endometrial tissue found out with endometrial cavity)

Question 9

Describe features of endometrial polyps

Answer 9

• Exophytic masses of variable size which project into the endometrial cavity.
• Can present with abnormal bleeding
• Treated via hysteroscope in outpatient clinic.
• Often there is thick walled blood vessels and fibrous stroma.
• Glands are usually inactive but can show proliferation, secretory changes or metaplasia

Question 10

Describe clinical features of endometrial hyperplasia and endometrial adenocarcinoma

Answer 10

• Associated with prolonged oestrogenic stimulation of endometrium.
• Could be caused by anovulatory cycles, endogenous sources of oestrogen (obesity, PCOS, tumours), exogenous sources of oestrogen (HRT).
  Symptoms include post menopausal bleeding
• Management for hyperplasia is progesterone therapy such as a Mirena or hysterectomy.
• Management of endometrial adenocarcinoma is treated with hysterectomy and further management.

Question 11

What are the histological features of endometrial hyperplasia

Answer 11

Histologically characterised by an increase in gland to stroma ration (less stroma between glands). Can be seen with or without atypia.
Atypical endometrial hyperplasia is known as a precursor for endometrial adenocarcinoma

Question 12

What is a leiomyoma and its symptoms

Answer 12

• Benign smooth muscle tumour of the myometrium, also known as fibroids
• Very common, can be singular or multiple.
• Symptoms include: Asymptomatic, abnormal bleeding, urinary frequency if large and impaired fertility

Question 13

What is the pathology and management of leiomyomas

Answer 13

Pathology - Sharpley demarcated, rough grey-white tumours with a whorled cut surface. Microscopically resembles smooth muscle cells
Management - Varies on number and size. Medical therapies include progesterone secreting IUS, hormonal therapies, tranexamic acid and GnRH antagonists. Surgical therapies include uterine artery embolisation, hysterectomy and myomectomy

Question 14

Describe features of Leiomyosarcoma

Answer 14

• Uncommon malignant smooth muscle tumour of the myometrium.
• Symptoms: Initially none then bleeding or pain.
• Pathology: Bulky invasive masses or polypoid, necrosis, haemorrhage and variable cut surface. Microscopically presents with overt cytological atypia, necrosis, mitotic activity and infiltrative margin.

Question 15

Describe features of endometrial stromal sarcoma

Answer 15

• Rare group of tumours,
• Diffusely infiltrative ‘worm like’ growth pattern seen macroscopically.
• Microscopically cells resemble proliferating endometrial stroma with mitoses.

Question 16

What are some gestational trophoblastic diseases?

Answer 16

• Umbrella term for hydatidiform moles (partial and complete) and frankly malignant tumours including choriocarcinoma.

Question 17

Describe a complete and partial mole

Answer 17

Partial - Fertilisation of one egg by two sperm resulting in a triploid karyotype. Risk of an invasive mole forming which invades and destroys the uterus
Complete mole - Fertilisation of an egg which has no genetic material so the sperm duplicates its chromosomal material. 10% occur when two sperm fertilise an egg with no genetic material. Microscopy shows enlarged villi with central cisterns and circumferential trophoblasts. This causes a diploid karyotype. Risk of an invasive mole which can become a choriocarcinoma (rapidly invasive).