2. Myometrium: Uterine Fibroids
⢠Pathology
ďźA fibroid is a benign tumour of uterine smooth muscle, a
leiomyoma.
⢠Gross appearance:
ďźFirm, whorled tumour located adjacent to & bulging into
the endometrial cavity (submucous fibroid)
ďźCentrally within the myometrium ( Intramural fibroids)
ďźAttached to uterus by narrow pedicle (Pedunculated
fibroid)
3. 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
4. Pathology
1. Red degeneration is due to acute disruption of
blood supply.
ďźMay present with acute onset of pain and tenderness over
the uterus,
ďźassoc with mild pyrexia & leukocytosis.
2. Hyaline degeneration;
ďźWhen fibroids outgrow its blood supply
6. 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
7. Pathophysiology
⢠Expât 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
8. 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 devât 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.
9. Pathophysiology
⢠Risk of malignant transformation 0.5%
⢠In leimyosarcoma, tissue are of more extensive
genetic Instability
⢠With frequent deletions especially involving
chromosomes 1 & 10
10. Clinical Features
⢠Common & detectable in 20% of women over 30yrs
⢠Autopsy shows prevalence of up to 50%.
⢠Risk factors
ďźNulliparity
ďźObesity
ďźA family history
ďźAfrican racial origin
⢠Majority donât cause symptoms & identified
coincidentally
11. Clinical Features
ďCommon PC
ďźMenstrual disturbances
ďźPressure symptoms esp. urinary frequency.
ďźPain is unusual except in acute degeneration
ďźMenorrhagia may occur coincidentally
12. 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.
13. 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
14. 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
15. 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
17. Tx
ďźConservative management is appropriate
ďźOvarian suppression using GnRH agonist
ďźMifepristone has been shown to be effective in shrinking
fibroids.
ďźChoice of tx is by patients PC and aspiration for normal
menstruation and fertility.
ďąHysteroscopic resection
ďąMyomectomy
Pretreatment with GnRH for 2 months facilitates the process.
18.
19. 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.