Uterus - Pathology

2021-02-22 12:00 AM

Endometritis is inflammation of the endometrial lining in the uterus.


Endometritis is inflammation of the endometrial lining in the uterus. It can be acute or chronic.

  • Acute endometritis is an ascending infection from the cervix; it is associated with pregnancy and abortion.
  • Chronic endometritis is associated with PID and intrauterine devices; plasma cells are seen in the endometrium.

Endometriosis is the presence of endometrial glands and stroma outside the uterus. It most commonly affects women of reproductive age. Common sites of involvement are the ovaries, ovarian and uterine ligaments, a pouch of Douglas, serosa of bowel and urinary bladder, and peritoneal cavity. It can present with chronic pelvic pain, dysmenorrhea and dyspareunia, rectal pain and constipation, abnormal uterine bleeding, or infertility.


Grossly, endometriosis causes red-brown serosal nodules (an endometrioma is an ovarian “chocolate” (hemolyzed blood) cyst).

Leiomyoma (fibroid), the most common tumour of the female genital tract, is a benign, smooth muscle tumour of the myometrium. Leiomyomas have a high incidence in African Americans, though they are common across all populations. Their growth is estrogen-dependent.

Leiomyomas may present with menorrhagia, abdominal mass, pelvic/back pain, suprapubic discomfort, or infertility and spontaneous abortion.

Grossly, leiomyomas form well-circumscribed, rubbery, white-tan masses with a whorled, trabeculated appearance on the cut section. Leiomyomas are commonly multiple and may have subserosal, intramural, and submucosal location. The malignant variant is leiomyosarcoma.

Endometrial hyperplasia refers to a histological proliferation of endometrial glands with 2 important histopathologic categories:

  • Benign endometrial hyperplasia shows uniform remodelling of glands with cyst formation.
  • Endometrial intraepithelial neoplasia shows the crowded architecture and cytologic alteration on biopsy.

o   Patients are at high risk for endometrial adenocarcinoma.

o   Treatment options include total hysterectomy or progestin therapy with biopsy surveillance.

Endometrial adenocarcinoma is the most common malignant tumour of the lower female genital tract. It most commonly affects postmenopausal women who present with abnormal uterine bleeding. Risk factors are mostly related to estrogen:

  • Early menarche and late menopause
  • Nulliparity
  • Hypertension and diabetes
  • Obesity
  • Chronic anovulation
  • Estrogen-producing ovarian tumours (granulosa cell tumours)
  • ERT and tamoxifen
  • Endometrial hyperplasia (complex atypical hyperplasia)
  • Lynch syndrome (colorectal, endometrial, and ovarian cancers)

Endometrial adenocarcinoma typically forms a tan polypoid endometrial mass; invasion of the myometrium is prognostically important.

  • Endometroid adenocarcinoma (most common histological type): associated with PTEN mutations
  • Serous tumours: associated with TP53 mutations

Less common types of uterine malignancy include leiomyosarcoma, a malignant, smooth muscle tumour, and carcinosarcoma, which contains both malignant stromal cells and endometrial adenocarcinoma.

Adenomyosis is an invagination of the deeper layers of the endometrium into the myometrium, which causes menorrhagia and dysmenorrhea.

Anovulation can cause abnormal uterine bleeding, especially in women near menarche and menopause. Biopsy shows the glandular and stromal breakdown in a back-ground of proliferative phase endometrium.