Sonography of Ovarian Masses

August 9, 2011

Sonography of Ovarian Masses Dr. Mohammed Abdalla Egypt, Domiat General Hospital   Determining whether a mass requires surgery remains a formidable challenge. As sonographic appearance may be similar in several types of ovarian masses and Ultrasound cannot provide histological information.

Sonography of Ovarian Masses
Dr. Mohammed Abdalla

Egypt, Domiat General Hospital

  Determining whether a mass requires surgery remains a formidable challenge.

As sonographic appearance may be similar in several types of ovarian masses and Ultrasound cannot provide histological information.

The endpoint should be whether or not a specific patient requires surgical intervention

Evaluate Ovarian Cancer Risk

The risk of ovarian cancer is 1 in 55 (1.8%), but Age and Family history may increase this risk.

Jemal A, Thomas A, Murray T, Thun M. Cancer statistics, 2002. CA Cancer J Clin. 2002;52:23-47.

Pre-test Probability

Age: In women of 60 to 69 years of age adnexal masses have 12 times the malignancy risk of those aged 20 to 30 years.

Family History:
The lifetime risk of ovarian cancer based on family history alone:

--> 6.7% for 1 first-degree relative with the disease to
--> 40% for women with hereditary syndrome

Transvaginal Sonographic Approach

Thanks for the transvaginal sonographic approach as it yields the greatest amount of information during real-time scanning.

By placing pressure on the transvaginal probe and on the patient's abdomen with the free hand you can elicit pelvic tenderness and helps the examiner assess the mobility and compressibility of an ovarian mass, as well as the consistency of its internal structures.

  By answering the next 8 questions you can determine whether or not a specific patient requires surgical intervention.

Question 1 What is the size of the lesion?

>10cm5-10cm<5cm
unsuitable for morphologic assessment and proceed to surgerymorphologic addessment should be considered on an individual basismorphology and Doppler studies may yield elevant info

 

Question 2Is the mass solid?

First exclude a pedunculated leiomyoma by visualizing a normal ovary on that side.

Solid ovarian masses are generally the smallest subset of ovarian tumors; approximately 10% are malignant.

Osmers RGW, Osmers M, VonMaydell B, Wagner B, Kuhn W. Preoperative evaluation of ovarian tumors in the premenopause by transvaginosonography. Am J Obstet Gynecol. 1996;175:428-434

Question 3 Is it a simple or complex cyst?

The risk that a simple, thin-walled cyst is malignant increases with patient age and the size of the cyst.

Although the risk of malignancy rises as loculated cysts become more complex, the mucinous cystadenomas contain multiple septations and fluid with fine debris secondary to their thick mucinous content

Question 4 Are papillary excrescences present?

These represent localized overgrowth of the epithelium. The likelihood of malignancy rises as the number of excrescences increases*

Papillary projections into the cyst cavity of less than 3 mm are not strongly associated with malignancy.**

* Granberg S, Norstrom A, Wikland M. Tumors in the lower pelvis as imaged by vaginal sonography. Gynecol Oncol. 1990;37:224-229.'
** Timmerman D, Bourne TH, Tailor A, et al. A comparison of methods for preoperative discrimination between malignant and benign adnexal masses: the development of a new logistic regression model. Am J Obstet Gynecol. 1999;181:57-65.

Question 5 Are there echo-dense foci?

• Benign cystic teratomas usually produces echogenic foci with acoustic shadowing, but some malignant tumors may have components that cast an acoustic shadow.
• 72% of cystic teratomas are avascular
• If the solid components of an apparent benign cystic teratoma have vascular flow, a struma ovarii consisting largely of thyroid tissue should be considered.

Question 6 Is there echogenicity of interior fluid?

• A serous cyst generally contains clear fluid
• A mucinous cysts contain fine debris
• An endometrioma tends to contain homogeneous debris A hemorrhagic cyst may have a ground-glass appearance
• Echogenic foci with acoustic shadowing are characteristic of a benign cystic teratoma

Question 7Is measurable fluid in the cul-de-sac?

• The production of cul-de-sac fluid is proportionate with ovarian activity. A postmenopausal patient has < 7 mL of cul-de-sac fluid.
• Since transvaginal ultrasound can consistently detect 8 mL or more of cul-de-sac fluid, no fluid is identified in the majority of postmenopausal patients.
• Thus, a moderate amount of cul-de-sac fluid in a postmenopausal patient should raise the sonologist's index of suspicion concerning a possible ovarian tumor.

Question 8How does the mass change over time?

A follow-up ultrasound examination in 6 to 8 weeks may provide additional information about a mass's etiology.

Repeat sonography is recommended in cases without obvious stigmata of malignancy or a size that would mandate surgery.

Ovarian Doppler
Because of the many types of ovarian masses, sonographic morphology is usually not pathognomonic and when used alone results in a high false positive rate in the diagnosis of malignancy. The role of color and pulse Doppler is to reduce these false positives.

Ovarian Doppler Findings suggestive of malignancy
Malignant tumors characteristically contain dilated, saccular, and randomly dispersed vessels. Centrally located flow, flow along septations, and flow within papillary excrescences also suggest malignancy.

Ovarian Doppler Findings suggesting a benign mass
Peripheral flow is more consistent with a benign neoplasm. Hemorrhage in a mass is highly suggestive of a benign mass or cyst.

Thank you