Reproductive: Masses of the Uterus and Vagina Flashcards
What are the major subtypes of uterine fibroids?
- Hyaline (most common)
- Hypercellular (more dense)
- Lipoleiomyoma (fat containing)
Are fibroids estrogen dependent?
Yes, they grow during pregnancy and involute with menopause
Note: This is also why they are rare before puberty.
MRI appearance of hyaline uterine fibroids
T1 dark and T2 dark with homogenous enhancement
MRI appearance of hypercellular uterine fibroids
T1 dark and T2 bright with homogenous enhancement
Note: These respond well to IR embolization.
MRI appearance of lipoleiomyoma
T1 bright (dark if fat sat) and T2 bright with possible rim enhancement
What are the 4 major types of uterine fibroid degeneration?
- Hyaline degeneration (most common)
- Red/carneous degeneration
- Myxoid degeneration (rare)
- Cystic degeneration (rare)
What is the most common type of fibroid degeneration?
Hyaline
Hyaline degeneration of a uterine fibroid
When the fibroid outgrows its blood supply, resulting in the accumulation of proteinaceous tissue
Carneous degeneration of a uterine fibroid
When venous thrombosis causes fibroid degeneration
Note: This usually occurs during pregnancy.
Which type of fibroid degeneration is classically T2 dark on MRI?
Hyaline degeneration
Which type of fibroid degeneration classically has a T1 bright peripheral rim?
Red (carneous) degeneration
What type of fibroid degeneration?
Red (carneous) degeneration
Note: T1 bright peripheral rim in the subacute phase.
What type of fibroid degeneration?
Myxoid degeneration
Note: T2 bright with minimal enhancement (hyaline degeneration is usually T2 dark).
What type of fibroid degeneration (no enhancement)?
Cystic degeneration
How can you tell whether a uterine fibroid has degenerated?
Absence or paucity of enhancement (normally uterine fibroids enhance avidly)
How can you differentiate a normal uterine fibroid from a uterine leiomyosarcoma
You can’t, but a rapidly enlarging fibroid with areas of necrosis should make you more suspicious of a leiomyosarcoma
Adenomyosis
When endometrial tissue is found within the myometrium
Risk factors for adenomyosis
- Multiple prior pregnancies
- Uterine procedures (e.g. c section, dilatation and curettage, etc.)
What portion of the uterus is most commonly affected by adenomyosis?
The posterior wall
Note: The cervix is usually spared.
Imaging findings of adenomyosis
- Thickening of the junctional zone on MRI (best imaging test)
- Enlarged uterus with normal contour
- Heterogeneous myometrium on ultrasound
Classic imaging finding for adenomyosis
Thickening of the junctional zone >12 mm on MRI (either focal or diffuse)
Note: You may also see T2 bright foci in the myometrium (endometrial cystic tissue).
Adenoomyosis
Note: Thickening of the junctional zone along the posterior uterine wall with T2 bright foci.
Adenomyosis
Note: Heterogeneous thickening of the junctional zone with cystic changes.
e
Junctional zone
Note: d is the endometrium and f is the myometrium.
A
Myometrium
B
Junctional zone
C
Endometrium
Imaging absence of the junctional zone is normal in what pts?
- Pre-puberty
- Postmenopausal
- During pregnancy and postpartum for 6 months (appears similar to myometrium)
How long does it take the junction zone to return to its normal MRI appearance after a pregnancy?
6 months after delivery
Note: Before this and during pregnancy the junctional zone appears too similar to myometrium to tell apart.
How thick is the endometrium allowed to be?
- Up to 12 mm (if proliferative trilaminar appearance)
- Up to 16 mm (if secretory homogeneously hyperechoic appearance)
- Up to 4 mm (if postmenopausal)
When should you recommend endometrial sampling in a postmenopausal pt?
Anytime the endometrium is 5 mm or thicker (especially if there is abnormal uterine bleeding)
What is the classic ovarian tumor that causes endometrial thickening?
Granulosa cell tumor of the ovary
Which genetic syndrome is associated with a 30-50x increased risk of endometrial cancer?
Hereditary Non-Polyposis Colon Cancer (HNPCC)
What is the most common type of endometrial cancer?
Adenocarcinoma (>90%)
What imaging study is used to stage endometrial cancer?
MRI (to determine myometrial invasion depth and cervical involvement)
Note: PET/CT is also used if there is concern for possible distant metastases. Most often, ultrasound/biopsy demonstrate stage 1 disease and additional imaging is not needed.
Which MRI sequence is best for finding enometrial cancer drop metastases in the vagina?
Diffusion imaging and ADC (mets will have restricted diffusion)
MRI appearance of endometrial cancer
- Restricted diffusion
- T1 hypoenhancing (relative to myometrium)
- T2 intermediate (T2 bright relative to junctional zone)
What are the key MRI findings when staging endometrial cancer?
- Myometrial invasion (less than or more than half)
- Cervical stromal invasion
At what point does stage 1a endometrial cancer become stage 1b?
Deep myometrial invasion (when the tumor invades more than half the myometrial thickness)
At what point does stage 1 endometrial cancer become stage 2?
Cervical stroma invasion
Note: Normal cervical mucosa enhancement on 2-3 min post contrast imaging excludes cervical stromal invasion.
What is the best study to look for nodal metastases in endometrial cancer?
PET/CT
How does management change from stage 1 to stage 2 endometrial cancer?
Stage 1 (usually total abdominal hysterectomy)
Stage 2 (usually preoperative radiation and radical hysterectomy)
What uterus changes are common in pts taking tamoxifen?
- Endometrial thickening
- Subendometrial cysts
- Endometrial polyps (30%)
Post menopausal pt
Think tamoxifen changes
Note: Multicystic endometrial thickening.
This pt most likely has a history of…
Breast cancer (and is taking tamoxifen)
Note: Cystic thickening of the endometrium, think tamoxifen changes.
Postmenopausal pts with tamoxifen changes to the endometrium can normally have endometrial thickening >10 mm. When should you biopsy?
If the pt is symptomatic (abnormal uterine bleeding)
Note: If asymptomatic, you shouldn’t do an endometrial biopsy in pts on tamoxifen (even if the endometrium is thickened).
Hyperechoic structure within the endometrium with vascularity, possible endometrial polyp. Recommend sonohysterogram.
When should sonohysterography be performed?
During the early proliferative phase (~days 4-6 of the menstrual cycle)
What is the most common type of cervical cancer?
Squamous cell carcinoma (90%)
Note: Usually related to HPV infection.
At what point does the management of cervical cancer change from surgery alone to chemotherapy/radiation?
From stage 2A (spread beyond the cervix, but no parametrial invasion)
to
Stage 2B (Parametrial invasion, but no extension to the pelvic sidewall)
Note: Invasion of the pelvic sidewall or lower 1/3 of the vagina will upgrade to stage 3a and also require chemo/radiation.
Parametrium
A fibrous band that separates the supravaginal cervix from the bladder (it extends between the layers of the broad ligament)
Note: The uterine artery runs inside the parametric, which is why parametrial invasion in cervical cancer requires chemotherapy.
What is the imaging sign of parametrial invasion in the setting of cervical cancer?
Disruption of the T2 dark cervical ring
Endometrial fluid (more than trace amount) in a postmenopausal pt with cervical cancer…
Think endometrial cavity outlet obstruction due to cervical stenosis secondary to the cervical cancer
Differential for solid vaginal mass
- Squamous cell carcinoma
- Cervical/uterine cancer prolapsing into the vagina
- Metastases
- Vaginal rhabdomyosarcoma (common in children)
- Clear cell adenocarcinoma (associated with maternal DES exposure)
- Leiomyoma
What is the most common type of vaginal cancer?
Squamous cell carcinoma (85%)
Note: Usually associated with HPV.
Maternal diethylstilbestrol (DES) exposure is a risk factor for what type of cancer?
Clear cell adenocarcinoma of the vagina
Vaginal rhabdomyosarcoma is most common in what pt population?
Bimodal distribution in young females:
- Ages 2-6
- Ages 14-18
Pediatric
Think vaginal rhabdomyosarcoma
Note: It can occur in the uterus, but more commonly starts in the vagina and invades the uterus secondarily.
What is the most likely primary cancer if you identify metastasis in the anterior wall of the upper 1/3 of the vagina?
Upper genital tract cancer, such as uterine (90%)
What is the most likely primary cancer if you identify a metastasis in the posterior wall of the lower 1/3 of the vagina?
GI tract (90%)
What are the major cystic lesions in the region of the cervix/vagina?
- Nabothian cyst
- Gartner duct cyst
- Skene gland cyst
- Bartholin gland cyst
Nabothian cyst
Gartner duct cyst
Note: Cyst in the mid vagina.
Gartner duct cyst
Note: Cyst in the mid vagina.
Pathophysiology of nabothian cysts
Cystic dilatation of mucous glands due to epithelial plugging in the setting of inflammation
Pathophysiology of Garner duct cysts
Incomplete regression of the Wolffian ducts
What is the most common location for a Gartner duct cyst?
Anterolateral wall of the upper vagina
Clinical manifestations of Gartner duct cysts
Urinary dysfunction (if there is mass effect on the urethra)
Pathophysiology of bartholin cysts
Cystic dilatation of the mucin-secreting Bartholin glands due to obstruction
Treatment for Bartholin cysts
- Nothing (if asymptomatic)
- Marsupialization (if symptomatic or infected)
How can you distinguish a Baththolin cyst from a Gartner duct cyst?
Batholin cysts happen below the pubic symphysis (Garner duct cysts are above)
Clinical manifestations of Skene gland cysts
- Asymptomatic (most common)
- Recurrent UTIs
- Urethral obstruction
Note: The Skene glands are periurethral.
Bartholin or Skene cyst
Note: Below the pubic symphysis.
Bartholin or Skene cyst
What are the most common cysts at each colored location?
Red (Gartner duct cyst)
Green (Skene gland cyst)
Blue (Bartholin gland cyst)
Skene or Barhtolin cyst
How can you differentiate a Skene cyst from a Bartholin cyst?
Skene cysts are periurethral (tend to be centered more anteriorly)
Bathrolin cysts are associated with the labia majora (and tend to be centered more posteriorly)
Note: Bartholin cysts are near the Butthole.