FibroidsFibroids are benign smooth muscle tumors arising from the myometrium. They are the MC benign tumors of uterus, and they are also the MC pelvic tumors in females.
- Predominantly estrogen-dependent tumors:
- Early menarche, late menopause
- Associated anovulation and PCOS
- Growing in size during pregnancy, and following menopause there is cessation of growth
- Nulliparity ("a uterus which does not bear a baby consoles itself by having a fibroid")
- Deletions in chromosome 7 and t (12,14) are associated with fibroids
- More common in colored races
- Infertility: Fibroids can cause infertility and infertile women are more prone to develop fibroids
- Smoking is protective for fibroids.
- Fibroids have a pseudocapsule and whorled appearance on cut section.
- They are firm in consistency, except when they undergo degeneration (then they become soft).
- Hyaline degeneration is the MC type, and sarcomatous is the least common variety.
- Sarcomatous degeneration occurs in 0.1-0.5% cases. It occurs in large fibroids and toward the center of the tumor. It resembles "raw pork."
- True broad ligament fibroid arises de novo in the broad ligament. Ureter is medial to this type of fibroid (it is between the uterus and fibroid).
- Pseudo broad ligament fibroid arises from the uterus and then grows in between two leaves of broad ligament.
- So the ureter is lateral to this type of fibroid.
- Anterior cervical fibroid irritates the trigone of bladder and can cause increase frequency of micturition, whereas posterior cervical fibroid can compress the urethra and cause acute retention of urine.
- Lantern on dome of St Paul's Cathedral is the description used for central cervical fibroid.
- The majority of fibroids remain asymptomatic.
- Menorrhagia is the classic symptom of symptomatic fibroids.
- U5G is the investigation of choice for fibroids.
- Red degeneration:
Type of Fibroids
5-10 MF/10 HPF
>10 M.F/l0 HPF
MF=mitotic figures, HPF=high power field
Causes of Symmetrical Enlargement of Uterus
- Submucous or intramural (solitary) fibroid
- Carcinoma body
Indications of surgery in asymptomatic fibroid:
- Size> 12 weeks of pregnancy
- Diagnosis not certain
- Fibroid grows during follow-up
- Subserous pedunculated fibroid (because of risk of torsion)
- Situated in the lower part of the uterus and likely to complicate deliveries in future
- Fibroids compressing ureter and causing hydroureter /hydronephrosis
- Unexplained infertility with distortion of uterine cavity
- Unexplained recurrent abortions
Drugs which decrease the size of fibroids (never for permanent treatment, as the fibroid grows back to its usual size after the action of drug is over; they are mainly used preoperatively):
- GnRH analogs (MC used)
- Progesterone (DMPA/Mirena/POP flow-dose OC pills)
- Mifepristone (RU-486) (fibroids are also partly progesterone dependent)
- Anastrozole (aromatase inhibitor)
- Asoprisnil (selective progesterone receptor modulator-SPRM)
GnRH analogs are used preoperatively:
- Decrease the vascularity and blood loss during surgery
- To induce amenorrhea to build up hemoglobin in cases of anemia
- May facilitate laparoscopic or hysteroscopic surgery
Methods to decrease blood loss during myomectomy:
- Hypotensive anesthesia
- Use of vasopressin intraoperatively
- Bonney's myomectomy clamp
- Preoperative GnRH analogs
- Uterine artery embolization (UAE)
In this procedure, the femoral artery is cannulated, and artificial clot of polyvinyl alcohol is used to block the uterine artery and its branches supplying the fibroids. It decreases the blood loss during surgery. The same technique can also be used as a therapy for symptomatic patients who refuse or want to avoid surgery. After embolization there is 60-65% decrease in size of fibroids over a period of 6-9 months, and so the patient's symptoms may decrease or disappear. If the patient is still symptomatic after 1 year, then surgery should be considered.
Even though pregnancies have been reported after UAE, patients desirous of pregnancy is a contraindication for UAE.
- High-intensity focused ultrasound (HIFU or FUS) is a highly precise medical procedure using high-intensity focused ultrasound waves to heat and destroy fibroids rapidly through ablation.
- Clinical HIFU procedures are typically image-guided (MRl or USG) to precisely target the fibroids before applying of ultrasound energy.
- When MRl is used for guidance, the technique is called magnetic resonance-guided focused ultrasound (MRgHIFU or MRgFUS). MRl is used to identify fibroids before they are destroyed by the ultrasound waves.
- When USG is used to localize the fibroids, the technique is called ultrasound-guided focused ultrasound (USgFUS).