Characterization of adnexal mass lesions on MR imaging

Accuracy of magnetic resonance imaging in ovarian tumor: a systematic quantitative review

OBJECTIVE

To estimate the diagnostic accuracy of magnetic resonance in ovarian tumors.

STUDY DESIGN

A quantitative systematic review was performed. Studies that compared magnetic resonance and paraffin sections within subjects for diagnosis of ovarian tumors were included.

RESULTS

Fifteen primary studies were analyzed, which included 1267 ovarian masses. For borderline or malignant ovarian cancer vs benign ovarian lesions, the pooled likelihood ratio for the occurrence of a positive magnetic resonance result was 6.6 (95% confidence interval, 4.7-9.2) and the posttest probability for borderline or malignant diagnosis was 77% (95% confidence interval, 70-82). Because specificity and likelihood ratio positive were heterogeneous, a random effect model was used and a summary receiver operating characteristic curve was generated. For borderline or malignant ovarian cancer vs benign ovarian lesions, the area under curve was 0.9526.

CONCLUSION

Magnetic resonance seems to be a useful preoperative test for predicting the diagnosis of pelvic masses.

Malignant transformation of an endometriotic cyst: MDCT and MR findings

Malignant transformation is a rare complication of endometriosis. MR criteria for diagnosis include the presence of soft-tissue components, enhancement after contrast material administration in an endometriotic cyst. We present the multidetector CT and MR imaging findings in a case of an incidentally found endometrioid adenocarcinoma in a left-sided ovarian endometrioma, occurring in a 30-year old woman. MR imaging enabled the correct preoperative characterization of the lesion, by depicting a soft-tissue element, with strong and early enhancement after gadolinium administration. The same area had high signal intensity on diffusion-weighted images and low apparent diffusion coefficient values due to restricted diffusion, findings also strongly suggestive of malignancy.

Characterization of complex adnexal masses: value of adding perfusion- and diffusion-weighted MR imaging to conventional MR imaging

PURPOSE

To retrospectively determine the value of adding perfusion-weighted (PW) and diffusion-weighted (DW) sequences to a conventional magnetic resonance (MR) imaging protocol to differentiate benign from malignant tumors.

MATERIALS AND METHODS

The institutional ethics committee approved this retrospective study and waived the requirement to obtain informed consent. MR images in 87 women (age range, 25-87 years) who underwent imaging before surgery for complex adnexal masses-excluding endometriomas and cystic teratomas-were analyzed. Conventional morphologic, perfusion, and diffusion MR criteria of malignancy were recorded. Three independent observers reviewed images in four steps: conventional MR images alone, conventional MR images and PW images combined, conventional MR images and DW images combined, and conventional, PW, and DW MR images combined. Receiver operating characteristic curve analysis was performed to compare the results of the readings. A recursive partitioning model was built to establish a multivariate decision tree.

RESULTS

There was almost perfect agreement for lesion characterization regardless of the reader experiment or step considered (κ = 0.811-0.929). Area under the receiver operating characteristic curve values were higher for conventional and DW images combined, conventional and PW images combined, and conventional, DW, and PW images combined compared with conventional MR images alone (P < .05). For all readers, the accuracy of conventional, PW, and DW imaging combined was higher than that of conventional MR imaging alone for benign masses (P < .01) but not for malignant masses (P = .24). The addition of both PW and DW images led to a correct change in the diagnosis in 19% (11 of 57 patients), 23% (13 of 57 patients), and 24% (14 of 57 patients) of cases for readers 1, 2, and 3, respectively, with no incorrect changes. Conventional, PW, and DW MR imaging criteria were combined to generate a decision tree giving an accuracy of 95%.

CONCLUSION

The addition of PW and DW sequences to a conventional MR imaging protocol improved the diagnostic accuracy in the characterization of complex adnexal masses.

Peri- and post-menopausal incidental adnexal masses and the risk of sporadic ovarian malignancy: new insights and clinical management

Adnexal masses are common among peri- and post-menopausal women. Although ovarian cancer is a significant cause of mortality in menopausal women, large population-based studies demonstrate that the majority of adnexal masses are benign. Despite this, the appearance of an adnexal mass is a concern for the patient and an insight exercise for physicians. In most cases, an adnexal enlargement is an incidental finding, generally corresponding to a benign cyst and easily diagnosed by conventional ultrasound. Exceptionally an ovarian tumour may be malignant and should be treated as early as possible. When conventional ultrasound renders complex morphology other diagnostic tools must be used such as: colour Doppler and functional tumour vessel properties, serum CA 125 levels, nuclear magnetic resonance imaging and in some cases laparoscopy. Several new tumour markers are being studied for clinical application, although there are presently no clear recommendations. Adnexal masses with benign morphological and functional properties must be periodically monitored as an alternative to surgery since malignant transformation is exceptional.

Ovarian Cancer: The Role of Functional Imaging as an End Point in Clinical Trials

The Gynaecological Cancer InterGroup conducts collaborative trials in gynecologic cancer and also aims to develop standards that can be used to strengthen all aspects of study methodology. There is an urgent need to develop more refined imaging end points that can be used as early treatment response biomarkers in ovarian cancer. Therefore, the Gynaecological Cancer InterGroup commissioned an expert position paper on the role of functional imaging as an end point in clinical trials in ovarian cancer. In this position paper, we state the limitation of current anatomical imaging methods used in clinical trials, highlight the potential of functional imaging, and provide key recommendations on the use of functional imaging as an end point in ovarian cancer clinical trials.

High-field magnetic resonance imaging of the pelvis: uterus, ovary, and prostate gland

Today, magnetic resonance imaging (MRI) is a standard imaging modality for various pathologic disorders in the human pelvis. It has given proof of its usefulness in the diagnosis of several benign and malignant disorders, and it is routinely used for the local staging of different tumors even when confined to specific parts of a pelvic organ. Signal-to-noise ratio and motion artifacts of the examined organ and adjacent bowel structures are major factors for image quality. Setting at 3 T with surface coils avoids technical limitations and discomfort of additional endovaginal or endorectal coils. Definition of high field seems fuzzy because of the availability of MRI machines with 3, 7 T, or higher; therefore, the general aspects of MRI of pelvic structures with emphasis on uterus, ovary, and prostate gland and attention to promising newer techniques such as 3 T, dynamic contrast imaging, and diffusion-weighted imaging are reviewed in this article.

Dynamic contrast-enhanced MRI in ovarian cancer: Initial experience at 3 tesla in primary and metastatic disease

The aim of this study was to develop and demonstrate a methodology for dynamic contrast-enhanced MRI at 3 T in patients with advanced ovarian cancer and to report the results from pharmacokinetic modeling of the data. Nineteen patients with suspected advanced ovarian carcinoma (FIGO stage 3 or higher) were enrolled in this prospective study. Up to three marker lesions were identified: primary ovarian mass, omental ''cake'', and peritoneal deposits. Dynamic contrast-enhanced MRI was performed using a three-dimensional T(1)-weighted gradient-echo acquisition with a temporal resolution of 1.6 sec, following intravenous administration of 0.1 mmol/kg gadobutrol. Precontrast T(1) mapping, using an inversion-recovery fast gradient-echo sequence, was also performed. Imaging was completed in 18/19 patients, although two were subsequently excluded based on pathology results. Pharmacokinetic modeling of the data was performed according to the extended Kety model, using an arterial input function formed by concatenation of the Fritz-Hansen and Weinmann curves. No statistically significant differences were found between the results for the three marker lesions. In the future, this work will allow kinetic modeling results from ovarian dynamic contrast-enhanced MRI to be correlated with response to treatment. The high temporal resolution allows good characterization of the rapid contrast agent uptake in these vascular tumors.

Current update on borderline ovarian neoplasms

OBJECTIVE

Borderline ovarian tumors comprise a unique group of noninvasive ovarian neoplasms with characteristic histology and variable tumor biology that typically manifest as low-stage disease in younger women with resultant excellent prognosis.

CONCLUSION

Borderline tumors are considered to be precursors of low-grade ovarian cancers. Accurate diagnosis and staging facilitate optimal patient management particularly in patients desiring to preserve fertility.

Patterns of misinterpretation of adnexal masses on CT and MR in an academic radiology department

RATIONALE AND OBJECTIVES

The aim of this study was to assess potential quality assurance (QA) issues in the diagnosis and characterization of adnexal masses on pelvic computed tomographic (CT) and magnetic resonance (MR) imaging studies.

MATERIALS AND METHODS

Images from 128 women who had oophorectomies during a 16-month period with CT and/or MR studies within 5 years of surgery (145 CT scans from 103 women and 49 MR studies from 42 women, with 17 having both MR and CT studies) were reviewed by three radiologists who assigned QA scores of 0 (no QA issue), 1 (minor issue with minimal impact on clinical care), or 2 (major issue with potential impact on clinical care). The difficulty of diagnosis was assigned a score of 0 (very difficult diagnosis to make), 1 (difficult but possible to make the diagnosis), or 2 (diagnosis should be made). The incidence of adnexal QA issues was calculated using total CT and MR pelvic examinations performed on women during the interval.

RESULTS

Twenty-nine QA issues were identified in 28 women in 17 of 145 CT studies (11.7%) and 12 of 49 MR examinations (24.5%) in women having adnexal surgery (17 of 11,194 [0.15%] of female pelvic CT studies and 12 of 603 [2.0%] of female pelvic MR studies performed in the time interval). Issues included missed lesions, lesions misidentified as leiomyomas, fat described in the lesion but not seen histologically, postmenopausal status of patient not considered, ultrasound correlation not recommended, and confusion of right and left sides.

CONCLUSION

Errors in CT and MR studies regarding the diagnosis and characterization of adnexal masses in a highly enriched population of women undergoing adnexal surgery are common. Knowledge of the types of QA issues found in CT and MR studies of adnexal masses should aid in decreasing future errors.

Contribution of diffusion-weighted MR imaging for predicting benignity of complex adnexal masses

The purpose of this study was to prospectively assess the contribution of diffusion-weighted MR imaging (DWI) for characterizing complex adnexal masses. Seventy-seven women (22-87 years old) with complex adnexal masses (30 benign and 47 malignant) underwent MR imaging including DWI before surgery. Conventional morphological MR imaging criteria were recorded in addition to b(1,000) signal intensity and apparent diffusion coefficient (ADC) measurements of cystic and solid components. Positive likelihood ratios (PLR) were calculated for predicting benignity and malignancy. The most significant criteria for predicting benignity were low b(1,000) signal intensity within the solid component (PLR = 10.9), low T2 signal intensity within the solid component (PLR = 5.7), absence of solid portion (PLR = 3.1), absence of ascites or peritoneal implants (PLR = 2.3) and absence of papillary projections (PLR = 2.3). ADC measurements did not contribute to differentiating benign from malignant adnexal masses. All masses that displayed simultaneously low signal intensity within the solid component on T2-weighted and on b(1,000) diffusion-weighted images were benign. Alternatively, the presence of a solid component with intermediate T2 signal and high b(1,000) signal intensity was associated with a PLR of 4.5 for a malignant adnexal tumour. DWI signal intensity is an accurate tool for predicting benignity of complex adnexal masses.

Magnetic Resonance Imaging in Gynecological Oncology

Magnetic resonance imaging (MRI) has become an indispensable tool in the assessment of malignant disease. With increasingly sophisticated systems and technical advancements, MRI has continued to expand its role in providing crucial information regarding cancer diagnosis and management. In gynecological malignancies, this modality has assumed greater responsibility, particularly in the evaluation of cervical and endometrial cancers. In addition to conventional imaging, innovative techniques such as dynamic contrast-enhanced MRI and diffusion-weighted MRI show promise in offering early assessment of tumor response. This paper reviews the current role of MRI in gynecological cancers and highlights the potential of novel techniques in improving patient care.

Dynamic contrast-enhanced MR imaging of ovarian neoplasms: current status and future perspectives

MR imaging is useful for characterizing ovarian tumors. Dynamic contrast-enhanced MR imaging is a promising new technique useful for characterizing perfusion and angiogenesis of ovarian masses. This article describes the dynamic contrast-enhanced MR imaging technique examines the current and future applications of this technique in patients with ovarian tumors.

MRI appearances of borderline ovarian tumours

This review was performed to describe the range of magnetic resonance imaging (MRI) appearances of borderline ovarian tumours. The MRI findings in 26 patients with 31 borderline ovarian tumours (mean age: 40.1 years, range: 14-85 years) were retrospectively reviewed. For each tumour, site, size, MRI characteristics, and enhancement following gadolinium administration were recorded. There were 20 serous and 11 mucinous borderline ovarian subtypes. Nine of 26 patients demonstrated bilateral disease on MRI; synchronous contralateral ovarian disease included three benign, five serous borderline, and one serous invasive tumour. A history of a metachronous mucinous borderline tumour was identified in one patient. MRI appearances were classified into four morphological categories: group 1 (6/31, 19%), unilocular cysts; group 2 (6/31, 19%), minimally septate cysts with papillary projections; group 3 (14/31, 45%), markedly septate lesions with plaque-like excrescences; and group 4 (5/31, 16%), predominantly solid with exophytic papillary projections, all of serous subtype. There was a significant difference in mean volume between serous (841.5 cm(3)) and mucinous (6358.2 cm(3)) subtypes (p=0.009). All tumours demonstrated at least one MRI feature suggestive of malignancy. The present review demonstrates the variable MRI appearances of borderline ovarian tumours along with imaging features suggestive of tumour subtype. In patients in whom the clinical features are suggestive of a borderline ovarian tumour (young age and normal or minimally elevated CA125), the ability to predict a borderline disease using morphological features observed on MRI would be extremely helpful in surgical planning, with the potential to offer fertility or ovary-preserving surgery. Future studies are required to further this aim.

Value of magnetic resonance imaging for the diagnosis of ovarian tumors: a review

This article reviews the value of magnetic resonance imaging (MRI) for the diagnosis of ovarian tumors especially when ultrasonography is indeterminate. Although ultrasonography is the first imaging technique used to investigate suspected pelvic masses, it has a limited capacity for tissue characterization. In addition to morphological characteristics, many tissue parameters such as T1, T2, perfusion, and diffusion contribute to signal intensity, so MRI is able to identify various types of tissue contained in pelvic masses. Magnetic resonance imaging helps to locate large solid masses and to distinguish benign from malignant ovarian tumors, with an overall accuracy of 88% to 93% for the diagnosis of malignancy. The aims of this review are 3-fold. First, we review state-of-the-art and usual MRI techniques and published findings. Second, we recall the MR features most useful for assessing the main ovarian tumors. Finally, we discuss the relevance of various features for distinguishing between benign, borderline, and invasive ovarian tumors.

Epithelial ovarian tumors: value of dynamic contrast-enhanced MR imaging and correlation with tumor angiogenesis

PURPOSE

To retrospectively evaluate the diagnostic performance of dynamic contrast material-enhanced magnetic resonance (MR) imaging for the characterization of ovarian epithelial tumors, by using histologic findings as the reference standard, and to correlate dynamic contrast-enhanced MR imaging findings with angiogenesis biomarkers.

MATERIALS AND METHODS

Ethics committee approval was obtained, with waiver of informed consent. Patients consented to having their data used for future retrospective research. Forty-one women (age range, 22-73 years) with 48 epithelial ovarian tumors underwent dynamic contrast-enhanced MR imaging before surgical excision. In case of bilateral tumors (n = 7), only the most complex tumor was analyzed. Thus, 41 tumors (12 benign, 13 borderline, and 16 invasive) were examined with dynamic contrast-enhanced MR imaging and immunohistochemical methods. Dynamic contrast-enhanced MR imaging parameters (enhancement amplitude [EA], time of half rising [T(max)], and maximal slope [MS]) were analyzed according to histopathologic findings, microvessel density, pericyte coverage index (PCI), and vascular endothelial growth factor receptor 2 (VEGFR-2) expression. Statistical analyses were performed by using Kruskal-Wallis, Fisher exact, and Spearman tests and receiver operating curve analysis.

RESULTS

EA was higher for invasive tumors than for benign (P < .001) and borderline (P < .05) tumors. T(max) was longer for benign tumors than for borderline (P < .05) and invasive (P < .01) tumors. MS was steeper for invasive tumors than for benign (P < .001) and borderline (P < .001) tumors. PCI was lower in invasive tumors than in borderline (P < .05) and benign (P < .05) tumors. Microvessels showed stronger immunohistochemical VEGFR-2 expression in invasive tumors than in benign or borderline tumors (P < .05). MS correlated with a lower PCI (r = -0.34, P = .04) and stronger VEGFR-2 expression by using both epithelial (r = 0.41, P < .01) and endothelial (r = 0.66, P < .001) cells.

CONCLUSION

The early enhancement patterns of ovarian epithelial tumors on dynamic contrast-enhanced MR images can help distinguish among benign, borderline, and invasive tumors and were found to correlate with tumoral angiogenic status.

MR imaging in ovarian cancer

Magnetic resonance (MR) imaging is increasingly being used in patients with gynaecological disorders due to its high contrast resolution compared to computed tomography (CT) and ultrasound. In women presenting with an adnexal mass, ultrasound remains the primary imaging modality in the detection and characterisation of such lesions. However, in recent years overwhelming evidence has accumulated for the use of MR imaging in patients with indeterminate adnexal masses particularly in younger women and where disease markers are unhelpful. In staging ovarian cancer and for evaluating therapeutic response MR imaging is as accurate as CT but CT remains the imaging modality of choice because it is more widely available and quicker. This article reviews that evidence and outlines a place for the use of MR imaging in ovarian cancer.

Magnetic resonance imaging of adnexal masses

Adnexal masses are common in women of all ages. A range of physiological and benign ovarian conditions that develop in women, especially in the reproductive age, and adnexal malignancies can be evaluated with magnetic resonance imaging (MRI). Management of women with adnexal masses is frequently guided by imaging findings; therefore, precise characterization of adnexal pathology should be performed whenever possible. Magnetic resonance imaging is useful in characterization of adnexal masses that are not completely evaluated by ultrasound because it can provide additional information on soft tissue composition of adnexal masses based on specific tissue relaxation times and allows multiplanar imaging at large field of view to define the origin and extent of pelvic pathology. The patients most likely to benefit from MRI are pregnant women and those who are premenopausal and have masses that have complex features on ultrasound but do not have raised cancer antigen 125 tumor marker levels. The overlap in imaging appearance among different cell type malignancies makes it difficult to predict exact histology based on MRI appearance; however, MRI has a high accuracy in differentiating benign from malignant masses. Teratomas, endometriomas, simple and hemorrhagic cysts, fibromas, exophytic or extrauterine fibroids, and hydrosalpinges can be diagnosed with high confidence. In this article, the authors review the histopathologic background and MRI features of adnexal masses and discuss the role of MRI in the differentiation of benign from malignant adnexal pathologies.

MR imaging evaluation of the adnexa

MR imaging has become an important tool in the evaluation of patients with adnexal disease, and its role continues to evolve. Some benign entities can be diagnosed by MR imaging with a high grade of confidence, such as teratomas, endometriomas, simple and hemorrhagic cysts, fibromas, and hydrosalpinx. In cases of malignant lesions, MR imaging may be more accurate than other modalities for lesion characterization, staging, and follow-up.

Differential diagnosis of adnexal masses: risk of malignancy index, ultrasonography, magnetic resonance imaging, and radioimmunoscintigraphy

A risk of malignancy index (RMI), based on menopausal status, ultrasound (US) findings, and serum CA125, has previously been described and validated in the primary evaluation of women with adnexal masses and is widely used in selective referral of women from local cancer units to specialized cancer centers. Additional imaging modalities could be useful for further characterization of adnexal masses in this group of women. A prospective cohort study was conducted of 196 women with an adnexal mass referred to a teaching hospital for diagnosis and management. Follow-up data was obtained for 180 women; 119 women had benign and 61 women malignant adnexal masses. The sensitivity and specificity of specialist US, magnetic resonance imaging (MRI), radioimmunoscintigraphy (RS), and the RMI were determined. We identified a subgroup of women with RMI values of 25-1000 where the value of further specialist imaging was evaluated. Sensitivity and specificity for specialist US were 100% and 57%, for MRI 92% and 86%, and for RS 76% and 87%, respectively. Analysis of 123 patients managed sequentially, using RMI cutoff values of > or =25 and <1000 and then US and MRI provided a sensitivity of 94% and a specificity of 90%. Using this RMI cutoff followed by specialist US and MRI, as opposed to the traditional RMI cutoff value of 250, can increase the proportion of patients with cancer appropriately referred in to a cancer center, with no change in the proportion of patients with benign disease being managed in a local unit.

Ovarian cancer

Imaging has become an essential part of the clinical management of patients with ovarian cancer, contributing to tumor detection, characterization, staging, treatment planning, and follow-up. Imaging findings incorporated into the clinical impression assist in creating a treatment plan specific for an individual patient. Advances in cross-sectional imaging and nuclear medicine (PET) have yielded new insights into the evaluation of tumor prognostic factors. A multimodality approach can satisfy the complex imaging needs of a patient with ovarian cancer; however, the success of such an approach always depends on available resources and on the skills of the physicians involved.

Magnetic resonance imaging of abdominal pain during pregnancy

The objective of this review is to demonstrate magnetic resonance imaging as an important adjunct to ultrasound and computed tomography in the evaluation of the pregnant patient with abdominal pain. With the advent of ultrafast T2-weighted pulse sequences, fetal and bowel motion cause minimal artifact on the images. An accurate diagnosis can often be made in a few minutes based on these high-contrast images performed in 2 or 3 planes. T1-weighted gradient echo images with and without fat saturation are useful for identifying blood and fat, especially in the case of adnexal masses. Gadolinium-diethylenetriamine pentaacetic acid is rarely used to diagnose inflammatory or obstructive disease and is reserved for those patients with suspected malignancies.

Imaging in gynecology

This chapter summarizes the diagnostic performance (sensitivity, specificity, positive and negative likelihood ratios) of ultrasound, computer tomography, and magnetic resonance imaging in the diagnosis of various gynecological diseases and tumors. Positron emission tomography is not discussed. Imaging in infertility, in the diagnosis of Mullerian duct anomalies and in gynecological oncology (staging of gynecological cancers, diagnosis of recurrence of gynecological cancer, diagnosis of trophoblastic tumors) is not dealt with. Ultrasound is the first-line imaging method for discrimination between viable intrauterine pregnancy, miscarriage and tubal pregnancy in women with bleeding and/or pain in early pregnancy, for discrimination between benign and malignant adnexal masses and for making a specific diagnosis in adnexal tumors (e.g. dermoid cyst, endometrioma, hemorrhagic corpus luteum, etc.), for diagnosing intracavitary uterine pathology in women with bleeding problems, and for confirming or refuting pelvic pathology in women with pelvic pain. Magnetic resonance imaging can have a role as a secondary test in the diagnosis of adenomyosis, 'deep endometriosis' (e.g. endometriosis in the rectovaginal septum or in the uterosacral ligaments), and in the diagnosis of extremely rare types of ectopic pregnancy (e.g. in the spleen, liver or retroperitoneum).

MRI of sonographically indeterminate adnexal masses

OBJECTIVE

The purpose of this study was to assess the ability of MRI to characterize sonographically indeterminate adnexal masses and to define the sonographic features contributing to indeterminate diagnoses.

MATERIALS AND METHODS

Two blinded radiologists retrospectively reviewed the MRI examinations of 87 patients with 95 sonographically indeterminate adnexal masses. Reviewers determined the origin of a mass, its tissue content (cystic, solid, complex cystic, or cystic and solid), tissue characteristics (fat, blood, fibrous, or leiomyomatous), and benignity versus malignancy. Sonograms were reviewed by three reviewers to determine the origin of a mass, its tissue content, and reasons for an indeterminate diagnosis. Sensitivity and specificity of MRI were calculated, and agreement of sonography and MRI with the final diagnosis was determined using kappa statistics. The final diagnosis was determined by histopathology, surgical findings, or imaging or clinical follow-up.

RESULTS

The sensitivity of MRI for identifying malignancy (n = 5) was 100% and its specificity for benignity (n = 90) was 94%. Excellent agreement was seen between MRI and the final diagnosis for determining the origin (kappa = 0.93), tissue content (kappa = 0.98), and tissue characteristics (kappa = 0.91) of a mass. Sonography had poor agreement with the final diagnosis for the origin (kappa = 0.19) and tissue content (kappa = 0.33) of a mass. The main reasons for indeterminate sonographic diagnoses were the inability to determine origin because of location and large mass size and the appearances of purely solid or complex cystic masses.

CONCLUSION

Sonographically indeterminate adnexal masses of uncertain origin and solid or complex cystic content benefit from further evaluation with MRI, which is highly accurate for identifying the origin of a mass and characterizing its tissue content, obviating surgery.

MR imaging compared with intraoperative frozen-section examination for the diagnosis of adnexal tumors; correlation with final histology

The aim was to compare the accuracy of magnetic resonance imaging (MRI) and intraoperative consultation (IC) for the diagnosis of adnexal masses, with reference to final histology. MRI was performed in 136 women with sonographically indeterminate adnexal masses. IC included macroscopic and frozen-section examination. Macroscopic examination and MRI determined size, nature, and presence of vegetations or solid portions within masses. All masses were characterized as benign or malignant according to previously published MR imaging and histopathologic criteria. Sensitivities, specificities, and predictive values for the diagnosis of malignancy of MRI and IC were assessed. Histology revealed 168 adnexal masses (99 benign, 23 borderline and 46 invasive). Frozen sections were examined in 151 cases. Among the 151 adnexal masses studied by both MRI and IC, respective sensitivities, specificities, positive and predictive values of both methods for the diagnosis of malignancy were 89.7% and 84.5%, 91.4% and 100%, 86.7% and 100%, and 93.4% and 91.3%. Sensitivities of MR imaging and frozen section for the diagnosis of serous versus mucinous borderline tumors were 33.3% and 93.3%, and 62.5% and 12.5%, respectively. MRI is less accurate than IC for characterizing adnexal masses. However, MRI may increase the relevance of IC for borderline mucinous tumors.

Female Pelvis

MR is the diagnostic imaging modality of choice for many disorders of the female pelvis. Benign uterine disease is well-demonstrated using rapid sequences and minimal examination time,whereas evaluation of malignancy is best performed with high-resolution techniques. Wide-spread availability of ultrafast sequences has expanded MR imaging applications to include evaluation of pelvic floor relaxation and fetal anomalies. Promising developments, such as new contrast agents, MR-guided focused ultrasound,and 3 tesla imaging, suggest continued advancement of MR imaging in the care of patients who have gynecologic disease.

The role of magnetic resonance imaging and ultrasound in patients with adnexal masses

AIMS

To evaluate the accuracy of ultrasonography (US) and magnetic resonance imaging (MRI) in characterizing adnexal masses, and to determine which patients may benefit from MRI.

METHODS

We prospectively studied 72 women (mean age 53 years, range 19 to 86 years) with clinically suspected adnexal masses. A single experienced sonographer performed transabdominal and transvaginal greyscale spectral and colour Doppler examinations. MRI was carried out on a 1.5T system using T1, T2 and fat-suppressed T1-weighted sequences before and after intravenous injection of gadolinium. The adnexal masses were categorized as benign or malignant without knowledge of clinical details, according to the imaging features which were compared with the surgical and pathological findings.

RESULTS

For characterizing lesions as malignant, the sensitivity, specificity and accuracy of MRI were 96.6%, 83.7% and 88.9%, respectively, and of US were 100%, 39.5% and 63.9%, respectively. MRI was more specific (p<0.05) than US. Both MRI and US correctly diagnosed 17 (24%) cases with benign and 28 (39%) cases with malignant masses. MRI correctly diagnosed 19 (26%) cases with benign lesion(s), which on US were thought to be malignant. The age, menopausal status and CA-125 levels in these women made benign disease likely, but US features were suggestive of malignancy (large masses and solid-cystic lesions with nodules).

CONCLUSION

MRI is more specific and accurate than US and Doppler assessment for characterizing adnexal masses. Women who clinically have a relatively low risk of malignancy but who have complex sonographic features may benefit from MRI.