Imaging of Benign Adnexal Masses: Characteristic Presentations on Ultrasound, Computed Tomography, and Magnetic Resonance Imaging

The physiological sonographic features of the ovary in healthy subjects: a joint systematic review and meta-analysis by the Italian Society of Gynecology and Obstetrics (SIGO) and the Italian Society of Endocrinology (SIE)

PURPOSE

There is a lack of uniformity in the definition of normal ovary ultrasound parameters. Our aim was to summarize and meta-analyze the evidence on the topic. Full-text English articles published through December 31, 2020 were retrieved via MEDLINE and Embase. Data available for meta-analysis included: ovarian follicular count, ovarian volume, and ovarian Pulsatility Index (PI) assessed by Doppler ultrasound.

METHODS

Cohort, cross-sectional, prospective studies with a single or double arm were considered eligible. Interventional studies were included when providing baseline data. Both studies on pre- and post-menopausal women were screened; however, data on menopausal women were not sufficient to perform a meta-analysis. Studies on pre-pubertal girls were considered separately. Eighty-one papers were included in the meta-analysis.

RESULTS

The mean ovarian volume was 6.11 [5.81-6.42] ml in healthy women in reproductive age (5.81-6.42) and 1.67 ml [1.02-2.32] in pre-pubertal girls. In reproductive age, the mean follicular count was 8.04 [7.26-8.82] when calculated in the whole ovary and 5.88 [5.20-6.56] in an ovarian section, and the mean ovarian PI was 1.86 [1.35-2.37]. Age and the frequency of the transducers partly modulated these values. In particular, the 25-30-year group showed the higher mean follicular count (9.27 [7.71-10.82]), followed by a progressive age-related reduction (5.67 [2.23-9.12] in fertile women > 35 years). A significant difference in follicular count was also found according to the transducer's upper MHz limit.

CONCLUSION

Our findings provide a significant input to improve the interpretation and diagnostic accuracy of ovarian ultrasound parameters in different physiological and pathological settings.

Management of adnexal mass: A comparison of five national guidelines

OBJECTIVES

General gynecologists are often the first to face a newly diagnosed adnexal mass. Bothering mass symptoms, fertility issues, and the effect of a possible surgical intervention on fertility in term of mechanical factor and ovarian follicular reserve are all considerations that should be accounted for. This study summarizes and compares five different adnexal mass management guidelines, enabling clinicians to peruse consensus and controversy issues, thus choosing the optimal management method.

DESIGN

We retrieved, reviewed and compared the most recent national guidelines of adnexal mass management from the national societies of the United States (American College of Obstetricians and Gynecologists), England (the Royal College of Obstetricians and Gynecologists), Canada (the Society of Obstetricians and Gynaecologists of Canada), Australia (the Royal Australian College of General Practitioners), and France (French College of Gynaecologists and Obstetricians).

RESULTS

There is a broad consensus regarding the role of transvaginal ultrasound as part of the initial evaluation of an adnexal mass and the radiological characteristics suggesting it being malignant. The role of transabdominal ultrasound or doppler mode is controversial. The use of MRI in cases of indeterminate adnexal masses is widely accepted. Ultrasound-guided aspiration is generally not recommended. There is a broad consensus that CA-125 should not be used as an ovarian cancer disease screening tool, though its role in the initial evaluation of adnexal masses is controversial. Risk prediction models are generally accepted, particularly the 'International Ovarian Tumor Analysis simple rules' and the 'Risk of Malignancy Index'.

CONCLUSION

Adnexal mass management national guidelines, though similar, had noticeable variations in the content, references cited, and recommendations made. While this variation might raise a concern as to the reproducibility of synthesizing literature, it can help practitioners present all spectra of recommendations and available data.

Guideline No. 403: Initial Investigation and Management of Adnexal Masses

OBJECTIVES

To aid primary care physicians, emergency medicine physicians, and gynaecologists in the initial investigation of adnexal masses, defined as lumps that appear near the uterus or in or around ovaries, fallopian tubes, or surrounding connective tissue, and to outline recommendations for identifying women who would benefit from a referral to a gynaecologic oncologist for further management.

INTENDED USERS

Gynaecologists, obstetricians, family physicians, general surgeons, emergency medicine specialists, radiologists, sonographers, nurses, medical learners, residents, and fellows.

TARGET POPULATION

Adult women 18 years of age and older presenting for the evaluation of an adnexal mass.

OPTIONS

Women with adnexal masses should be assessed for personal risk factors, history, and physical findings. Initial evaluation should also include imaging and laboratory testing to triage women for management of their care either by a gynaecologic oncologist or as per SOGC guideline no. 404 on the initial investigation and management of benign ovarian masses.

EVIDENCE

A search of PubMed, Cochrane Wiley, and the Cochrane systematic reviews was conducted in January 2018 for English-language materials involving human subjects published since 2000 using three sets of terms: (i) ovarian cancer, ovarian carcinoma, adnexal disease, ovarian neoplasm, adnexal mass, fallopian tube disease, fallopian tube neoplasm, ovarian cyst, and ovarian tumour; (ii) the above terms in combination with predict neoplasm staging, follow-up, and staging; and (iii) the above two sets of terms in combination with ultrasound, tumour marker, CA 125, CEA, CA19-9, HE4, multivariable-index-assay, risk-of-ovarian-malignancy-algorithm, risk-of-malignancy-index, diagnostic imaging, CT, MRI, and PET. Relevant evidence was selected for inclusion in descending order of quality of evidence as follows: meta-analyses, systematic reviews, guidelines, randomized controlled trials, prospective cohort studies, observational studies, non-systematic reviews, case series, and reports. Additional articles were identified through cross-referencing the identified reviews. The total number of studies identified was 2350, with 59 being included in this review.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the authors. The Executive and Board of the Society of Gynecologic Oncology of Canada reviewed the content and submitted comments for consideration. The Board of Directors of the Society of Obstetricians and Gynaecologists of Canada approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology framework (Table A1 of Online Appendix A). See Table A2 of Online Appendix A for the interpretation of strong and weak recommendations. The summary of findings is available upon request.

BENEFITS, HARMS, COSTS

Adnexal masses are common, and guidelines on how to triage them and manage the care of patients presenting with adnexal masses will continue to guide the practice of primary care providers and gynaecologists. Ovarian cancer outcomes are improved when initial surgery is performed by a gynaecologic oncologist, likely as a result of complete surgical staging and optimal cytoreduction. Given these superior outcomes, guidelines to assist in the triage of adnexal masses and the referral and management of the care of patients with an adnexal mass are critical.

SUMMARY STATEMENTS (GRADE RATINGS IN PARENTHESES)

RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Guideline No. 404: Initial Investigation and Management of Benign Ovarian Masses

OBJECTIVE

To provide recommendations for a systematic approach to the initial investigation and management of a benign ovarian mass and facilitate patient referral to a gynaecologic oncologist for management.

INTENDED USERS

Obstetricians, gynaecologists, family physicians, internists, nurse practitioners, radiologists, general surgeons, medical students, medical residents, fellows, and other health care providers.

TARGET POPULATION

Women ≥18 years of age presenting for evaluation of an ovarian mass (including simple and unilocular cystic masses, endometriomas, dermoids, fibromas, and hemorrhagic cysts) who are not acutely symptomatic and without known genetic predisposition to ovarian cancer.

OUTCOMES

This guideline aims to encourage conservative management and help reduce unnecessary surgery and long-term health complications, maintain fertility, and decrease operative costs and improve overall patient care and outcomes by providing criteria for referral of patients with ultrasound imaging findings suggestive of a malignant mass to a gynaecologic oncologist.

EVIDENCE

Databases searched: Medline, Cochrane, and PubMed. Medical terms used: benign asymptomatic and symptomatic ovarian cysts, adnexal masses, oophorectomy, ultrasound diagnosis of cysts, simple ultrasound rules, surgical and medical therapies for cysts, screening for ovarian cancer, ovarian torsion, and menopause. Initial search was completed by 2017 and updated in 2018. Exclusion criteria were malignant ovarian cystic masses, endometriosis therapies, and other adnexal pathologies unrelated to the ovary.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the authors. The Society of Obstetricians and Gynaecologists of Canada's Board of Directors approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development and Evaluation methodology framework.

BENEFITS, HARMS, COSTS

Implementation of the recommendations could reduce costs due to unnecessary surgeries and hospitalizations and reduce lost work days and the risk of loss of fertility, early menopause, and surgical complications.

SUMMARY STATEMENTS (GRADE RATINGS IN PARENTHESES)

RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Two Patients With Meigs' Syndrome and Elevated Serum CA-125: A Case Report

Patients with Meigs' syndrome and elevated serum CA-125 are not frequently reported. A 59-year-old woman and a 48-year-old woman sought help because of progressive shortness of breath caused by pleural effusion. The presence of a pelvic mass was noted in both the patients and was thought to be the cause of the effusion. Both patients had elevated serum CA-125, which raised the possibility of malignancy. After complete resection of the tumors, the pathologic reports confirmed a benign and a low-grade malignant ovarian neoplasia, respectively. We comment on the outcome and follow-up of these two cases and briefly review Meigs' syndrome.

Imaging of Benign Adnexal Disease

This article provides an overview of the imaging evaluation of benign ovarian and adnexal masses in premenopausal and postmenopausal women and lesions discovered during pregnancy. Current imaging techniques are discussed, including pitfalls and differential diagnosis when necessary, as well as management. It also reviews the now well-established American College of Radiology (ACR)/Society of Radiologists in Ultrasound consensus guidelines and covers the more recently introduced Ovarian-Adnexal Reporting and Data System by the ACR and the recently published ADNEx Scoring System.

Magnetic Resonance Imaging of Pelvic Masses: A Compartmental Approach

Magnetic resonance imaging (MRI) is often "one stop shop" for evaluating female pelvic masses that helps in diagnosis, staging, and restaging of these tumors. A pelvic mass can arise from any tissue present within the pelvis. Although most masses in the female pelvis arise from the reproductive organs, masses may also arise from the gastrointestinal tract, urinary system, adjacent soft tissues, peritoneum, etc. It may not always be possible to determine the site of origin or distinguish these masses based on imaging characteristics. However, familiarity with the clinicopathologic and MRI features of most common pelvic masses helps in narrowing the differential diagnosis. Diagnosis of these masses needs a holistic approach as required for any tumor including clinical history, laboratory data, and imaging characteristics. We focus on MRI characteristics of commonly encountered pelvic masses. A compartmental imaging approach is discussed in this article that helps in identifying and characterizing these masses.

First International Consensus Report on Adnexal Masses: Management Recommendations

The First International Consensus Conference on Adnexal Masses was convened to thoroughly examine the state of the science and to formulate recommendations for clinical assessment and management. The panel included representatives of societies in the fields of gynecology, gynecologic oncology, radiology, and pathology and clinicians from Europe, Canada, and the United States. In the United States, there are approximately 9.1 surgeries per malignancy compared to the European International Ovarian Tumor Analysis center trials, with only 2.3 (oncology centers) and 5.9 (other centers) reported surgeries per malignancy, suggesting that there is room to improve our preoperative assessments. The American College of Obstetricians and Gynecologists Practice Bulletin on "Management of Adnexal Masses," reaffirmed in 2015 (Obstet Gynecol 2007; 110:201-214), still states, "With the exception of simple cysts on a transvaginal ultrasound finding, most pelvic masses in postmenopausal women will require surgical intervention." The panel concluded that patients would benefit not only from a more conservative approach to many benign adnexal masses but also from optimization of physician referral patterns to a gynecologic oncologist in cases of suspected ovarian malignancies. A number of next-step options were offered to aid in management of cases with sonographically indeterminate adnexal masses. This process would provide an opportunity to improve risk stratification for indeterminate masses via the provision of alternatives, including but not limited to evidence-based risk-assessment algorithms and referral to an "expert sonologist" or to a gynecologic oncologist. The panel believed that these efforts to improve clinical management and preoperative triage patterns would ultimately improve patient care.

Correlation of pelvic magnetic resonance imaging diagnosis with pathology for indeterminate adnexal masses

OBJECTIVES

The aim of this study was to determine the accuracy of pelvic magnetic resonance imaging (MRI) diagnoses compared with the final pathology diagnoses for a series of women with indeterminate adnexal masses.

MATERIALS AND METHODS

We performed a retrospective cohort study of women who underwent pelvic MRI with a diagnosis of an adnexal mass between June 2009 and 2010 after indeterminate ultrasound at our tertiary care institution. Chart abstraction was performed for demographic information and radiologic interpretations (benign or malignant) and favored a specific histologic subtype on MRI reports. The radiologic diagnoses were compared with the diagnoses by surgical pathology.

RESULTS

Data from 237 female patients who underwent pelvic MRI were included, and 41.35% underwent surgical intervention for the adnexal mass. Pelvic MRI (n = 88) was determined to have a sensitivity of 95.0% and specificity of 94.1%. The predicted specific histologic subtype by MRI (n = 84) was accurate in 56 (98.25%) of 57 women with an anticipated benign diagnosis and in 23 (85.19%) of 27 women with an anticipated malignancy. The agreement between a benign diagnosis from MRI and benign final surgical pathology was 0.85 (95% confidence interval, 0.716-0.976).

CONCLUSIONS

In our tertiary care center, MRI is used to further characterize indeterminate adnexal masses and can accurately differentiate benign versus malignant adnexal masses. The diagnosis on MRI was highly correlative with the final histopathology. The majority of the cohort (59%) were able to be managed expectantly based on reassuring results of the MRI. Magnetic resonance imaging offered diagnostic value, more detailed patient counseling, appropriate subspecialty referral, and surgical planning, as well as reassurance to pursue conservative management of benign masses by MRI.

Benign and Suspicious Ovarian Masses-MR Imaging Criteria for Characterization: Pictorial Review

Ovarian masses present a special diagnostic challenge when imaging findings cannot be categorized into benign or malignant pathology. Ultrasonography (US), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI) are currently used to evaluate ovarian tumors. US is the first-line imaging investigation for suspected adnexal masses. Color Doppler US helps the diagnosis identifying vascularized components within the mass. CT is commonly performed in preoperative evaluation of a suspected ovarian malignancy, but it exposes patients to radiation. When US findings are nondiagnostic or equivocal, MRI can be a valuable problem solving tool, useful to give also surgical planning information. MRI is well known to provide accurate information about hemorrhage, fat, and collagen. It is able to identify different types of tissue contained in pelvic masses, distinguishing benign from malignant ovarian tumors. The knowledge of clinical syndromes and MRI features of these conditions is crucial in establishing an accurate diagnosis and determining appropriate treatment. The purpose of this paper is to illustrate MRI findings in neoplastic and non-neoplastic ovarian masses, which were assessed into three groups: cystic, solid, and solid/cystic lesions. MRI criteria for the correct diagnosis and characteristics for differentiating benign from malignant conditions are shown in this paper.

Sonographic Appearance of Bilateral Hemorrhagic Cysts of the Ovaries With Rupture on Transvaginal Sonography

Hemorrhagic ovarian cysts often present with acute abdomen, requiring laparotomy if features are suggestive of rupture. In an appropriate clinical setting, diagnosis may be possible on transvaginal sonography in most cases, but at times it may be difficult to recognize and can be confused with other ominous conditions. The authors describe the sonographic appearance of bilateral hemorrhagic ovarian cysts with rupture.