Ross & Wilson Anatomy and Physiology in Health and Illness (211 page)

Disorders of the uterine body

Endometritis

This is usually caused by non-specific infection, following childbirth or miscarriage, especially if fragments of membranes or placenta have been retained in the uterus. It may also be caused by an intrauterine contraceptive device (IUD). The inflammation may subside after removal of retained products or the IUD. The infection may spread to surrounding pelvic structures, e.g. uterine tubes, or deeper layers of the uterus.

Endometriosis

This is the growth of endometrial tissue outside the uterus, usually in the ovaries, uterine tubes and other pelvic structures. The ectopic tissue, like the uterine endometrium, responds to fluctuations in sex hormone levels during the menstrual cycle, causing menstrual-type bleeding into the lower abdomen and, in the ovaries, the formation of coloured cysts, ‘chocolate cysts’. There is intermittent pain due to swelling, and recurrent haemorrhage causes fibrous tissue formation. Ovarian endometriosis may lead to pelvic inflammation, infertility and extensive pelvic adhesions, involving the ovaries, uterus, uterine ligaments and the bowel.

Adenomyosis

This is the growth of endometrium within the myometrium. The ectopic tissue may cause general or localised uterine enlargement. The lesions may cause dysmenorrhoea and irregular excessive bleeding (menorrhagia), usually beginning between 40 and 50 years of age.

Endometrial hyperplasia

Hyperplasia of the endometrium is associated with high blood oestrogen levels, e.g. in obesity, oestrogen therapy or an ovarian tumour. Sometimes it is associated with increased risk of malignant change.

Leiomyoma (fibroid, myoma)

These are very common, often multiple, benign tumours of myometrium. They are firm masses of smooth muscle encapsulated in compressed muscle fibres and they vary greatly in size. Large tumours may undergo degenerative changes if they outgrow their blood supply, leading to necrosis, fibrosis and calcification. They develop during the reproductive period and may be hormone dependent, enlarging during pregnancy and when oral contraceptives are used. They tend to regress after the menopause. Large tumours may cause pelvic discomfort, frequency of micturition, menorrhagia, irregular bleeding, dysmenorrhoea and reduced fertility. Malignant change is rare.

Endometrial carcinoma

This occurs mainly in women who have never been pregnant and is most common between 50 and 60 years of age. The incidence is increased when an oestrogen-secreting tumour is present and in women who are obese, hypertensive or diabetic, because they tend to have a high level of blood oestrogen. As the tumour grows, there is often ulceration and vaginal bleeding. Endometrium has no lymphatics, so lymph spread is delayed until there is extensive local spread that involves other pelvic structures. Distant metastases, spread in blood or lymph, develop later, most commonly in the liver, lungs and bones. Invasion of the ureters leads to hydronephrosis and uraemia, commonly the cause of death.

Disorders of the uterine tubes and ovaries

Acute salpingitis

Salpingitis is inflammation of the uterine tubes. It is usually due to infection spreading from the uterus, and only occasionally from the peritoneal cavity. The uterine tubes may be left permanently damaged by fibrous scar tissue, which can cause obstruction and infertility. Infection may spread into the peritoneum and involve the ovaries.

Ectopic pregnancy

This is the implantation of a fertilised ovum outside the uterus, most commonly in a uterine tube. As the fetus grows the tube may rupture and its contents enter the peritoneal cavity, causing acute inflammation (peritonitis) and possibly severe intraperitoneal haemorrhage.

Ovarian tumours

The majority of ovarian tumours are benign, usually occurring between 20 and 45 years of age. The rest occur mostly between 45 and 65 years and are divided between borderline malignancy (low-grade cancer) and frank malignancy.

Ovarian cancer is associated with developed societies, higher socioeconomic groups, and, in some families, a genetic susceptibility. Pregnancy and the use of the contraceptive pill have a protective effect. Most malignancies of the ovary arise from epithelium, but some arise from the germ cells of the ovary, or from stromal cells.

Metastatic ovarian tumours

The ovaries are a common site of metastatic spread from primary tumours in other pelvic organs, the breast, stomach, pancreas and biliary tract.

Female infertility

This common condition may be due to:

•
blockage of uterine tubes, often the consequence of pelvic inflammatory disease

•
anatomical abnormalities, e.g. retroversion (tilting backwards) of the uterus

•
endocrine factors; any abnormalities of the glands and hormones governing the menstrual cycle can interfere with, for example, ovulation or the uterine cycle

•
low body weight, e.g. in anorexia nervosa, or severe malnourishment

•
endometriosis.

Disorders of the breast

Mastitis (inflammation of the breast)

Acute non-suppurative mastitis

This occurs during lactation and is associated with painful congestion and oedema of the breast. It is of hormonal origin.

Acute suppurative (pyogenic) mastitis

The microbes enter through a nipple abrasion caused by the infant sucking. The most common causative microbes are
Staphylococcus aureus
and
Streptococcus pyogenes
usually acquired by the infant while in hospital. The infection spreads along the mammary ducts of a lobe causing localised swelling and redness. If it does not resolve it can become chronic and an abscess may form.

Tumours of the breast

Benign tumours

Most breast tumours (90%) are benign. Fibroadenomas are the commonest type and occur any time after puberty; incidence peaks in the third decade. Some are cystic and some solid, and they usually occur in women nearing the menopause. They may originate from secretory cells, fibrous tissue or from ducts.

Malignant tumours

The most common types of tumour are usually painless lumps found in the upper outer quadrant of the breast. There is considerable fibrosis around the tumour that may cause retraction of the nipple and necrosis and ulceration of the overlying skin. It is increasingly common between 35 and 70 years.

Early spread beyond the breast is via lymph to the axillary and internal mammary nodes. Local invasion involves the pectoral muscles and the pleura. Blood-spread metastases may occur later in many organs and bones, especially lumbar and thoracic vertebrae. The causes of breast cancer are not known, but an important predisposing factor appears to be high oestrogen exposure. Women with an early menarche, a late menopause, and no pregnancies have a higher than normal risk because they experience more menstrual cycles in their lifetimes, and each monthly cycle brings with it the oestrogen surge seen during the proliferative phase (
p. 445
). A genetic component is also likely, with close relatives of breast cancer sufferers having an elevated risk of developing the disease. In about 15% of cases, the disease is linked to the presence of one of two faulty genes, BRCA1 and BRCA2. Women carrying one of these genes have a very high (80–90%) chance of developing the disease, and there is also increased risk of ovarian and bowel cancer. In women carrying these genes, the average age at which the disease appears is significantly lower than in those without the gene. One per cent of all breast cancer occurs in men.

Diseases of the male reproductive system

Learning outcomes

After studying this section, you should be able to:

outline the causes and effects of penile and urethral infections

describe the main pathologies of the testis

discuss the principal disorders of the prostate gland

list the main causes of male infertility.