• Bohm-Velez M, Fleischer AC, Andreotti RF, Fishman EK, Horrow MM, Hricak H, Thurmond A, Zelop C, Expert Panel on Women's Imaging. Suspected adnexal masses. [online publication]. Reston (VA): American College of Radiology (ACR); 2005. 10 p. [22 references]

This is the current release of the guideline.

It updates a previously published version: Bohm-Velez M, Mendelson E, Bree R, Finberg H, Fishman EK, Hricak H, Laing F, Sartoris D, Thurmond A, Goldstein S. Suspected adnexal masses. American College of Radiology. ACR Appropriateness Criteria. Radiology. 2000 Jun;215 Suppl:931-8.

The appropriateness criteria are reviewed annually and updated by the panels as needed, depending on introduction of new and highly significant scientific evidence.

ACR Appropriateness Criteria®

Clinical Condition: Suspected Adnexal Mass

Variant 1: Premenopausal female.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 2: Postmenopausal female.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 3: Premenopausal female with complex or solid mass evaluated by TAS, TVS, or both; positive pregnancy test.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 4: Premenopausal female with complex or solid mass evaluated by TAS, TVS, or both; negative pregnancy test.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 5: Premenopausal female with complex mass evaluated by TVS: not changed in 6 weeks.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 6: Postmenopausal female with a simple ovarian cyst >5 cm in diameter by TAS, TVS, or both.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 7: Postmenopausal female with a simple ovarian cyst 3 to 5 cm in diameter by TAS, TVS, or both.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 8: Postmenopausal female with a simple ovarian cyst <3 cm in diameter by TAS, TVS, or both.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 9: Postmenopausal female with simple ovarian cyst <5 cm and RI <0.4 or PI <1.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 10: Postmenopausal female with a complex or solid adnexal mass by TAS, TVS, or both.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Adnexal masses have a long list of diagnostic possibilities, and US study should be correlated with history and laboratory tests. Morphological analysis of adnexal masses with US can help narrow the differential diagnosis; however, US cannot always distinguish malignant from benign masses with the accuracy sufficient to avert surgery. Transabdominal ultrasound (TAS) and transvaginal ultrasound (TVS) complement each other, and in many facilities, patients are scanned by both techniques.

The applications of TVS in evaluating adnexal masses have been well described. TVS is useful where TA studies are suboptimal in studying obese patients, or for women who have a large amount of intestinal gas or are unable to adequately distend their bladders. The improved resolution of high-frequency transducers within the vagina increases the diagnostic confidence level in evaluating adnexal masses to about 72% to 78%. TVS can be used not only to differentiate between cystic and solid masses but also to improve characterization of the septations, mural nodules, and echogenicity of cystic and complex ovarian masses by giving additional information on the wall thickness and inner wall. TVS has increased the specificity to 83% for diagnosing ovarian cancer.

In addition, TVS can be used to assess the vascularity of a mass and provide a guide for aspiration of certain masses. However, due to the narrow field of view of the TV probe, TAS is needed to provide an overview of the relationship of the mass to other pelvic structures. TVS also can help determine the origin of the mass. When evaluating pelvic masses, it is important to determine its origin-whether it is ovarian or extraovarian. Masses arising from the ovary can be separated from extraovarian masses by identifying a rim of compressed ovarian parenchyma around the mass, which can form a break sign. Masses arising from the fallopian tube are usually seen as distended fusiform tubular structures in the lateral aspect of the uterine cornua. Masses arising from the uterus are usually solid, and there is no cleavage plane between the mass and the uterus.

TVS can help in characterizing a mass sonographically as cystic, solid, or complex. Cystic masses are usually ovarian or tubal. A simple cystic mass is an anechoic mass with smooth thin walls, no mural nodules or septations, and associated with acoustic enhancement. Identification of a cyst has extremely important implications for subsequent management. Sonographic identification of a simple cystic mass establishes a benign process in 100% of premenopausal women and in 95% of postmenopausal women. There are no solid data to support recommendations for specific follow-up intervals. Cysts in premenopausal females will resolve spontaneously and need not be removed unless torsion or rupture occurs. In postmenopausal women, cysts are seen with a frequency of 17% and are not related to hormonal therapy or time since onset of menopause. Theses cysts may disappear (53%), not change (28%), enlarge (11%), decrease (3%), or increase and decrease (6%). Although adnexal cysts 5 cm or less in postmenopausal females are not considered malignant, a 3 to 5 cm cyst may need to be correlated with CA 125 and Doppler findings. TVS aspiration of simple cysts, done by some, is controversial since either peritoneal contamination by ovarian cancer cells or pseudomyxoma peritonei may result. TVS aspiration plays an important role in diagnosis and treatment of tubovarian abscesses (TOAs) and diagnosis of recurrent ovarian cancer.

Most solid adnexal masses are pedunculated fibroids. Leiomyomas are the most common uterine neoplasms, and 20% to 30% occur in women older than 30 years of age. Pedunculated or subserosal fibroids sometimes can be very difficult to differentiate from solid extraovarian masses.

Solid intraovarian masses include benign ovarian tumors such as cystic teratomas, fibromas, thecomas, malignant ovarian tumors, and ovarian torsion. The most common ovarian neoplasm is benign cystic teratoma, which has a broad spectrum of sonographic appearances. When the diagnosis is in doubt, CT can depict the fat, teeth (7%) or bony fragments (18%). All solid intraovarian masses should be removed surgically. Complex adnexal masses are usually ovarian in origin, and in premenopausal females, most commonly represent hemorrhage cysts or endometriomas. The sonographic characteristics suggest the diagnosis, and a follow-up US can be done in six weeks to evaluate for resolution. In the appropriate clinical setting, tubovarian abscesses, ectopic pregnancies, and ovarian torsions can present as complex masses; therefore, a pregnancy test is important to narrow the differential diagnosis.

Even though US cannot definitely distinguish malignant from benign neoplasms, it provides useful information. Various authors have devised morphologic scoring systems for pelvic masses to predict ovarian malignancy based on size, internal borders, and presence of septa, papillary projections, and echogenicity. The presence of mural nodules or septations suggests that an adnexal mass is a neoplasm. Three-dimensional sonographic morphologic assessment does not appear to improve the diagnosis of complex adnexal masses.

Color flow and Doppler have been proposed to help distinguish between malignant and benign adnexal masses. The overall accuracy of characterization of benign and malignant masses was 94% for morphologic appearance and 80% with color and duplex Doppler imaging, with no significant difference in sensitivity. One study compared TVS Doppler with TVS findings. However, using a RI cutoff of 0.72 gave a sensitivity of 92.6% and specificity of 52.6%, similar to results obtained with TVS alone. Malignant masses are usually vascular. The low resistant Doppler waveform with PI <1 or RI <0.4 seen in malignant lesions can also be demonstrated in inflammatory masses, vascular benign neoplasms, endometriomas, corpus luteal cysts, and ectopic pregnancies. A positive value of 73% for diagnosing malignant masses with TV color Doppler imaging will result in one out of four masses that are called malignant by US to be benign histologically. High PI or RI suggests benignity; however, malignant tumors may show relatively high impedance flow also. The overlap of these indices in benign and malignant masses limits their clinical usefulness.

The combination of color Doppler with serum CA 125 has been proposed to increase sensitivity for differentiating benign from malignant ovarian tumors. When increasing the cutoff point of CA 125 from 35 U/mL to 65 U/mL in the presence of resistive index <5, the best specificity (100%) and positive predictive value (PPV) (100%) were reached.

The goal of the US examination is not simply evaluation of the adnexal mass, but the ability to combine the ancillary features such as hydronephrosis; ascites; pleural effusions; and liver, peritoneal, or omental metastasis which will help in the diagnosis and overall assessment. In problematic cases, MRI may help to determine the origin of a mass (uterine versus ovarian) and help distinguish benign from malignant with an overall accuracy of 91%. On MRI, identification of vegetations in cystic masses and ascites are the best indicators of malignancy. In addition, MRI increases the confident diagnosis of mature cystic teratoma, and leiomyoma.

CT is not indicated for the differential diagnosis of adnexal masses because of poor soft tissue discrimination, except when identification of fat and calcifications is important to make the diagnosis. In addition, CT involves radiation exposure, which is a disadvantage compared to US and MRI.

The sensitivity and specificity of PET in evaluating suspected adnexal masses in asymptomatic females are 58% and 76%, respectively. However, PET may play a role in women with known history of malignancy who present for evaluation of an adnexal mass.

Abbreviations

• CT, computed tomography
• IVU, intravenous urogram
• MRI, magnetic resonance imaging
• PET, positron emission tomography
• PI, pulsatility index
• RI, resistive index
• TA, transabdominal
• TV, transvaginal
• US, ultrasound

Algorithms were not developed from criteria guidelines.

The recommendations are based on analysis of the current literature and expert panel consensus.

• Bohm-Velez M, Fleischer AC, Andreotti RF, Fishman EK, Horrow MM, Hricak H, Thurmond A, Zelop C, Expert Panel on Women's Imaging. Suspected adnexal masses. [online publication]. Reston (VA): American College of Radiology (ACR); 2005. 10 p. [22 references]

Not applicable: The guideline was not adapted from another source.

1996 (revised 2005)

American College of Radiology - Medical Specialty Society

The American College of Radiology (ACR) provided the funding and the resources for these ACR Appropriateness Criteria®.

Committee on Appropriateness Criteria, Expert Panel on Women's Imaging

Panel Members: Marcela Böhm-Vélez, MD; Arthur C. Fleischer, MD; Rochelle F. Andreotti, MD; Elliot K. Fishman, MD; Mindy M. Horrow, MD; Hedvig Hricak, MD, PhD; Amy Thurmond, MD; Carolyn Zelop, MD

Not stated

This is the current release of the guideline.

It updates a previously published version: Bohm-Velez M, Mendelson E, Bree R, Finberg H, Fishman EK, Hricak H, Laing F, Sartoris D, Thurmond A, Goldstein S. Suspected adnexal masses. American College of Radiology. ACR Appropriateness Criteria. Radiology. 2000 Jun;215 Suppl:931-8.

The appropriateness criteria are reviewed annually and updated by the panels as needed, depending on introduction of new and highly significant scientific evidence.

None available

This NGC summary was completed by ECRI on February 13, 2006.