Uterine Fibroids

Defined as benign tumour of uterine smooth muscle, known as leiomyoma.
A firm tumour with whorled appearance.
Can arise from the :



a) Submucous fibroid

Arises from adjacent and protruding into endometrial cavity

b) Intramural fibroid

Arising centrally from the myometrium

c) Subserous fibroid

Arising from the outer border of myometrium

d) Pedunculated fibroid

Attached to the uterus by a narrow-pedicle (containing blood vessels)

3 types of degeneration :

a) Red degeneration

Typically occurs during pregnancy, when there's acute disruption of blood supply to the fibroids.
Presented as acute abdomen during pregnancy, with mild pyrexia and leucocytosis.
Symptoms can be severe enough to induce pre-term labour, and even causing miscarriage.
However, with proper management, acute phase usually subsides few days later.
Treatment : Admission, IV analgesics (opiates) and IV fluids, with adequate bed rest.

b) Hyaline and cystic degeneration

As the fibroids outgrows the blood supply, central necrosis occurs.
This leaves a central cavity within the fibroid, which undergone cystic degeneration.

The end stage of natural history of fibroids is : calcification of fibroids, occasionally seen in abdominal X ray of post-menopausal women.

Rarely, it turns to malignant lesion.

Clinical features :

More than 20% of females above age of 30 years old is affected by fibroids.
In most cases, it's asymptommatic.
Hence, usually detected accidentally by patient herself, or detected during cervical smear, or laproscopic sterilisation.

The commonest presenting complaints are :

Menstrual disturbances
Pressure symptoms

The commonest menstrual disturbance caused by fibroids is : Menorrhagia, believed to be due to submucous fibroids that distorts endometrial cavity, increasing endometrial surface area.

Pressure symptoms : Increased frequency of micturition, constipation

Presence of uterine fibroids can cause subfertility in women, by :

Compression of the fallopian tube
Distortion of endometrial cavity - preventing implantation


If pregnancy is established, it doesn't increase the risk of miscarriage.
However, it may cause abnormal fetal lie, delay in engagement, or even preventing normal vaginal delivery.

In abdominal examination, a hemi-ovoid firm mass is felt per abdomen, arising from the pelvis. During PV, the mass is mobile horizontally, but not vertically.

Diagnosis

Various causes of abdominopelvic masses in females of reproductive age group should be suspected.
Uterine enlargement caused by pregnancy VS uterine fibroid = latter is firmer
Benign or Malignant ovarian cyst need to be rule out
Leiomyosarcoma, although rare, but should raise suspicion if there's general signs of cachexia.

Investigations

FBC - to determine if there's any underlying significant anemia
USG pelvis - accurately provide information regarding the origin of the mass
USG renal tract should be done - to rule out hydroureter and hydronephrosis
If Leiomyosarcoma is suspected - needle biopsy or even urgent laprotomy 

Management

For asymptommatic fibroids, medical treatment can be tried first.
The current approved drug for shrinking of fibroid is GnRH analogues.
Though effective in shrinking of fibroid, but once ovarian function resumes, recurrance rate is high.

Surgical management will depends on :

Patient's presenting complaint
Her aspiration of menstrual function and fertility

If the presenting complaint is menorrhagia, associated with a fibroid polyp/submucous fibroid, definite management is Hysteroscopic resection of fibroids.

If the presenting complaints involves pressure symptoms, treatment of choice will be myomectomy.
Before proceeding to myomectomy, various risk and benefits need to be discussed with the patient, since :

a) Increased risk of uterine rupture in future pregnancies
b) Small, but significant risk of uncontrolled haemorrhage during myomectomy, which later may warrant a need of hysterectomy.

Hence, for females who have complete their family, doesn't wish to conceive anymore, vaginal hysterectomy is the choice of surgery.

2 months before surgery, treatment can be augmented by GnRH analogue to reduce size of fibroids and it's vascularity.

Hence, a pfannenstiel incision can be made to remove the fibroids, or vaginal hysterectomy can be done without having to remove it through laprotomy.

Both surgeries are associated with rapid recovery and less post-operative complications.

Category: Gynecology Notes