Uterine Fibroids

By: Oriba Dan Langoya, MBchBObs / Gyn Seminar

04/09/2014

Myometrium: Uterine Fibroids

• PathologyA fibroid is a benign tumour of uterine smooth muscle, a

leiomyoma.

• Gross appearance:

Firm, whorled tumour located adjacent to & bulging into

the endometrial cavity (submucous fibroid)

Centrally within the myometrium ( Intramural fibroids)

Attached to uterus by narrow pedicle (Pedunculated

fibroid)

Pathology

• Fibroids can arise separately from the uterus esp.

from broad lig presumably embryonal remnants

• Appearance may be altered and 3 form are;

1. Red

2. Hyaline

3. Cystic

Pathology

1. Red degeneration is due to acute disruption of

blood supply.

May present with acute onset of pain and tenderness

over the uterus,

assoc with mild pyrexia & leukocytosis.

2. Hyaline degeneration;

When fibroids outgrow its blood supply

Location of uterine Polyps

Pathophysiology

•Aetiology

• Key feature is occurrence in reproductive yrs.

• Racial or familial predisposition.

• Possibility of abnormal ER has been explored

• Both main Progesterone Receptor subtypes are expressed

in myoma & normal myometrium

Pathophysiology

• Exp’t Progesterone has been shown to stimulate production of apoptosis-inhibiting protein and EGF.• Oestradiol has the effect of stimulating expression

of EGF• Reduced expression of Inhibitory factors eg MCP-1

may contribute to loss of inhibitory required for fibroid growth• Tx by Ovarian suppression is assoc with increase in

MMP and decease in TIMP activity

Pathophysiology

• Cytogenic studies: Indiv Myoma are monoclonal in origin but ell from diff myomas within the uterus are independent in origin• Clonal expansion of tumour cell precede dev’t of

cytogenic aberration• Common cytogenic aberations are detected in

chromosomes 12, 6, 7 , aring chrom 1 & translocation involving 12 & 14.• Relevant areas on chrom 12, 6 & 7 contain putative

GR & TSG.

Pathophysiology

• Risk of malignant transformation 0.5%

• In leimyosarcoma, tissue are of more extensive

genetic Instability

• With frequent deletions especially involving

chromosomes 1 & 10

Clinical Features

• Common & detectable in 20% of women over 30yrs

• Autopsy shows prevalence of up to 50%.

• Risk factorsNulliparityObesityA family history African racial origin

• Majority don’t cause symptoms & identified coincidentally

Clinical Features

Common PC

Menstrual disturbances

Pressure symptoms esp. urinary frequency.

Pain is unusual except in acute degeneration

Menorrhagia may occur coincidentally

Clinical Features

• Subfertility may result from mechanical distortion or

occlusion of Fallopian tube

• Prevention of implantation esp by submucous

fibroids

• Risk of miscarriage is not increased once pregnancy

is established

• In late pregnancy may be the cause of abnormal lie.

Clinical Features

• Postpartum hemorrhage may occur due to

inefficient uterine contraction.

• Abdominal examination may indicate presence of a

firm mass arising from pelvis

• Bimanual exams; the mass is felt to be part of the

uterus usually with some mobility

Differential diagnosis

• Other causes of abdominopelvic mass should be evaluated.

• Uterus with fibroids is firm in contrast to that enlarged with pregnancy.

• An ovarian tumour

• Leimyosarcoma typically resent with rapidly enlarging abdominopelvic mass.

Less mobility of uterus than expetedin fibroid and general signs of cachexia

Investigations

1. Clinical features alone is usually sufficient

2. Hb conc to help indicate anaemia if there is clinically significant menorrhagia.

3. Ultrasonography is is useful in distinguishing a uterine from an ovarian mass.

4. Imaging of Urinary tract to exclude hydronephrosis

5. Clinical suspicion of sarcoma: do needle biopsy or urgent laparotomy

Hysteroscopic appearance of fibroid polyp within the endometrial cavity

Tx

Conservative management is appropriate

Ovarian suppression using GnRH agonist

Mifepristone has been shown to be effective in shrinking

fibroids.

Choice of tx is by patients PC and aspiration for normal

menstruation and fertility.

Hysteroscopic resection

Myomectomy

Pretreatment with GnRH for 2 months facilitates the process.

Management

a) Pelvic examination often reveals an enlarged &

tender uterus.

b) If the woman has no symptoms and the uterus is

not enlarged, no tx is indicated.

c) If the woman is symptomatic, hysterectomy is the

preferred tx, since adenomyosis does not respond

well to hormonal treatment.

THE END