Ovarian cancer: the clinical role of US, CT, and MRI

Pelvic mass associated with raised CA 125 for benign condition: a case report

BACKGROUND

Raised CA 125 with associated pelvic mass is highly suggestive of ovarian malignancy, but there are various other benign conditions that can be associated with pelvic mass and a raised CA 125.

CASE PRESENTATION

We present a case of 19 year old, Caucasian British woman who presented initially with sudden onset right sided iliac fossa pain and on imaging was found to have 9.8 x 4.5 cm complex cystic mass in right adnexa with a raised CA 125 of 657, which was initially thought to be highly suspicious of cancer but was subsequently found to be due to pelvic inflammatory disease on histology.

CONCLUSION

This case highlights the fact that though a pelvic mass with raised CA 125 is highly suggestive of malignancy, pelvic inflammatory disease should always be considered as a differential diagnosis especially in a young patient and a thorough sexual history and screening for pelvic infection should always be carried out in these patients.

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.

Positron emission tomography in ovarian cancer: 18F-deoxy-glucose and 16alpha-18F-fluoro-17beta-estradiol PET

The most frequently used molecular imaging technique is currently 18F-deoxy-glucose (FDG) positron emission tomography (PET). FDG-PET holds promise in the evaluation of recurrent or residual ovarian cancer when CA125 levels are rising and conventional imaging, such as ultrasound, CT, or MRI, is inconclusive or negative. Recently, integrated PET/CT, in which a full-ring-detector clinical PET scanner and a multidetector helical CT scanner are combined, has enabled the acquisition of both metabolic and anatomic imaging data using one device in a single diagnostic session. This can also provide precise anatomic localization of suspicious areas of increased FDG uptake and rule out false-positive PET findings. FDG-PET/CT is an accurate modality for assessing primary and recurrent ovarian cancer and may affect management. FDG-PET/CT may provide benefits for detection of recurrent of ovarian cancer and improve surgical planning. And FDG-PET has been shown to predict response to neoadjuvant chemotherapy and survival in advanced ovarian cancer. This review focuses on the role of FDG-PET and FDG-PET/CT in the management of patients with ovarian cancer. Recently, we have evaluated 16α-18F-fluoro-17β-estradiol (FES)-PET, which detects estrogen receptors. In a preliminary study we reported that FES-PET provides information useful for assessing ER status in advanced ovarian cancer. This new information may expand treatment choice for such patients.

Clinical management of borderline tumours of the ovary: results of a multicentre survey of 323 clinics in Germany

The aim of this survey was to analyse the standard of care in diagnostic, surgery, chemotherapy and aftercare management for patients with borderline tumours of the ovary (BOTs) in Germany. A structured questionnaire comprising different dimensions was sent to all 1114 gynaecological departments. The questionnaire could be returned anonymously. The overall response rate was 29.0% (323 departments). Most departments were on secondary care (71.8%), tertiary care (23.2%) or university hospital (5.0%) level. Most clinicians performed not more than five BOT operations (89.2%) per year. Most departments (93.2%) used in addition to classical bimanual examination and vaginal ultrasound, tumour marker CA-125 detection, CT scan, MRI or PET-CT techniques. Departments in university and tertiary care hospitals performed more often a fresh frozen section (87 vs 64%). In young women, clinicians performed much seldom unilateral salpingo-oophorectomy (92%) and only in 53% biopsies of the contralateral ovary. Generally, biopsies of the contralateral ovary were performed in 4-53% of the patients. Chemotherapy was mostly favoured in 'high-risk' patients with tumour residual, microinvasion or invasive implants. Thus, a high grade of insecurity in diagnostic and therapy of BOT exists in some gynaecological departments and underlines the need for more educational and study activities.

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.

The accurate staging of ovarian cancer using 3T magnetic resonance imaging--a realistic option

OBJECTIVES

The aim of the study was to determine whether staging primary ovarian cancer using 3.0 Tesla (3T) magnetic resonance imaging (MRI) is comparable to surgical staging of the disease.

DESIGN

A retrospective study consisting of a search of the pathology database to identify women with ovarian pathology from May 2004 to January 2007.

SETTING

All women treated for suspected ovarian cancer in our cancer centre region.

SAMPLE

All women suspected of ovarian pathology who underwent 3T MRI prior to primary surgical intervention between May 2004 and January 2007.

METHODS

All women found to have ovarian pathology, both benign and malignant, were then cross checked with the magnetic resonance (MR) database to identify those who had undergone 3T MRI prior to surgery. The resulting group of women underwent comparison of the MR, surgical and histopathological findings for each individual including diagnosis of benign or malignant disease and International Federation of Gynecology and Obstetrics (FIGO) staging where appropriate.

MAIN OUTCOME MEASURES

Comparisons were made between the staging accuracy of 3T MRI and surgical staging compared with histopathological findings and FIGO stage using weighted kappa. Sensitivity, specificity and accuracy were calculated for diagnosing malignant ovarian disease with 3T MRI.

RESULTS

A total of 191 women identified as having ovarian pathology underwent imaging with 3T MR and primary surgical intervention. In 19 of these women, the ovarian disease was an incidental finding. The group for which staging methods were compared consisted of 77 women of primary ovarian malignancy (20 of whom had borderline tumours). 3T MRI was able to detect ovarian malignancy with a sensitivity of 92% and a specificity of 76%. The overall accuracy in detecting malignancy with 3T MRI was 84%, with a positive predictive value of 80% and negative predictive value of 90%. Statistical analysis of the two methods of staging using weighted kappa, gave a K value of 0.926 (SE +/-0.121) for surgical staging and 0.866 (SE +/-0.119) for MR staging. A further analysis of the staging data for ovarian cancers alone, excluding borderline tumours resulted in a K value of 0.931 (SE +/-0.136) for histopathological staging versus MR staging and 0.958 (+/-0.140) for histopathological stage versus surgical staging.

CONCLUSION

Our study has shown that MRI can achieve staging of ovarian cancer comparable with the accuracy seen with surgical staging. No previous studies comparing different modalities have used the higher field strength 3T MRI. In addition, all other studies comparing radiological assessment of ovarian cancer have grouped the stages into I, II, III and IV rather than the more clinically appropriate a, b and c subgroups.

Radiological staging of ovarian cancer: imaging findings and contribution of CT and MRI

Ovarian cancer is the most lethal among the gynecologic malignancies with approximately 70% of patients presenting with advanced tumor stage. The prognosis of patients with ovarian cancer is directly related to the tumor stage and residual tumor burden after cytoreductive surgery. Exploratory laparotomy has been the cornerstone in the management of ovarian cancer, as it offers staging and tumor debulking. Understaging at initial laparotomy, however, is a problem in up to 30%, mainly due to insufficient technique and unexpected peritoneal spread outside the pelvis. Sites difficult to assess intraoperatively including the posterior aspect of the liver and the dome of the diaphragm can be well demonstrated with multiplanar imaging. CT and alternatively MRI have been accepted as adjunct imaging modalities for preoperative staging ovarian cancer. Of these, multidetector CT is the imaging modality of choice for staging ovarian cancer. In a multidisciplinary team approach patient management may be guided towards an individualized treatment plan. The contribution of imaging includes (1) surgery planning including referral practice, (2) selection of candidates for primary chemotherapy by demonstration of non (optimally) resectable disease, and (3) tissue sampling in peritoneal carcinomatosis.

Surgical management of women with ovarian cancer

Ovarian carcinoma remains a leading cause of cancer-related death among women. Proper treatment of ovarian cancer begins with a thorough staging operation and attempt to totally debulk tumor sites. Despite even maximal surgical efforts, most patients with ovarian cancer require systemic or intraperitoneal chemotherapy. Even though aggressive therapies are effective for the treatment of ovarian cancer, recurrence of the disease is common and often necessitates salvage surgical procedures and chemotherapy.

Three-dimensional ultrasound and three-dimensional power Doppler in the assessment of ovarian tumors

OBJECTIVE

To determine preoperative method that predicts nature of ovarian tumors.

METHODS

Fifty patients with complex pelvic masses assessed preoperatively with two-dimensional ultrasound (2DUS), two-dimensional power Doppler (2DPD), three-dimensional ultrasound (3DUS), three-dimensional power Doppler (3DPD), color Doppler.

RESULTS

All patients underwent exploration, 19 (38%) had benign tumors, 31 (62%) had ovarian cancer. 2DUS identified 29 cases suspicious for malignancy giving sensitivity, specificity, PPV and accuracy of 80%, 78%, 86%, and 80%. 2DUS with 2DPD identified 28 suspicious cases giving sensitivity, specificity, PPV and accuracy of 80%, 84%, 89%, and 82%. 3DUS identified 31 suspicious cases including 28 cancers giving sensitivity, specificity, PPV and accuracy of 90%, 84%, 90%, and 88%. 3DUS with 3DPD, identified 34 suspicious cases including all 31 cancers giving sensitivity, specificity, PPV and accuracy of 100%, 84%, 91%, and 94%. Color Doppler RI of 0.48 identified 28 cases of 31 cancers giving sensitivity of 90%.

CONCLUSION

Evaluation by 3DUS with 3DPD improves diagnostic accuracy of ovarian tumors.

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.

Ultrasonography, computed tomography and magnetic resonance imaging for diagnosis of ovarian carcinoma

Our objective was to compare US, CT, and MR imaging in differentiation of malignant from benign ovarian tumors. Through an electronic literature search and manual review of bibliographies (January 1990 to June 2006), relevant studies on the diagnostic performance of US, CT, and MR imaging in the differentiation between benign and malignant ovarian tumours were identified. Sixty-nine articles were included, yielding 143 studies. Data on the accuracy of the different imaging modalities were analyzed and compared by constructing summary receiver-operating characteristic (ROC) curves. Our results suggest that US techniques seems to be similar with CT and MRI in differentiation of malignant from benign ovarian tumors. The results also revealed that color Doppler flow imaging alone is significantly inferior to combined US techniques, morphologic assessment alone and contrast enhanced US in diagnosis of ovarian cancer. In conclusion, US morphologic assessment still is the most important and common modality in detect ovarian cancer.

Characterization of an intraperitoneal ovarian cancer xenograft model in nude rats using noninvasive microPET imaging

MicroPET is a noninvasive imaging modality that can potentially track tumor development in nude rats using the radiotracer fluorine 18-fluorodeoxyglucose (18F-FDG). Our goal was to determine whether microPET, as opposed to more invasive techniques, could be used to noninvasively monitor the development of ovarian cancer in the peritoneal cavity of nude rats for monitoring treatment response in future studies. Female nude rats were inoculated intraperitoneally with 36 million NIH:OVCAR-3 cells. Imaging was carried out at 2, 4, 6, or 8 weeks postinoculation. Each rat was fasted overnight and intravenously injected with 11.1 MBq (300 μCi) of18F-FDG in 0.2 mL of saline. Thirty minutes following injection, the rats were placed in the microPET and scanned for 30 min. After imaging, rats were euthanized for ascites and tissue collection for biodistribution and histopathologic correlation. Standard uptake values (SUVs) of18F-FDG within the peritoneal cavity were also calculated from regions of interest analysis of the microPET images. MicroPET images showed diffuse increased uptake of18F-FDG throughout the peritoneal cavity of tumor rats (mean SUV = 4.64) compared with control rats (mean SUV = 1.03). Ascites gathered from tumor-bearing rats had increased18F-FDG uptake as opposed to the peritoneal fluid collected from control rats. Biodistribution data revealed that the percent injected dose per gram (% ID/g) was significantly higher in tumor-bearing rats (6.29%) than in control rats (0.59%) in the peritoneal lymph nodes. Pathology verified that these lymph nodes were more reactive in tumor-bearing rats. By 6 weeks, some rats developed solid masses within the peritoneum, which could be detected on microPET images and confirmed as tumor by histopathology.18F-FDG uptake in these tumors at necropsy was 2.83% ID/g. These results correlate with previous invasive laparoscopic studies of the same tumor model and demonstrate that microPET using18F-FDG is a promising noninvasive tool to localize and follow tumor growth in an intraperitoneal ovarian cancer model.

Total-body MR-imaging in oncology

Although MRI is an effective modality in oncology, state-of-the-art total-body MRI (TB-MRI) in the past was infeasible in the diagnostic work-up, due to the need for repeated examinations with repositioning and separate surface coils to cover all body parts. To overcome this limitation, either a moving table platform in combination with the body-coil or a special designed rolling table platform with one body phased-array coil have been implemented with promising results for both tumor staging and metastases screening. Since 2004, state-of-the-art TB-MR imaging with high spatial resolution has become feasible using a newly developed 1.5 Tesla TB-MRI system with multiple receiver channels. This review gives an overview based on the recent literature as well as our own experience concerning the possibilities, challenges, and limitations of TB-MRI in oncology, emphasizing both oncological staging and early tumor detection in asymptomatic subjects.

Biomarkers in cancer staging, prognosis and treatment selection

Advances in genomics, proteomics and molecular pathology have generated many candidate biomarkers with potential clinical value. Their use for cancer staging and personalization of therapy at the time of diagnosis could improve patient care. However, translation from bench to bedside outside of the research setting has proved more difficult than might have been expected. Understanding how and when biomarkers can be integrated into clinical care is crucial if we want to translate the promise into reality.

18F-FDG PET/CT in the evaluation of recurrent ovarian cancer: a prospective study on forty-one patients

AIM

Many patients with ovarian cancer are at high risk of recurrence especially in the 2 years following first-line therapy. CA125 serum levels measurement associated to computed tomography (CT), ultrasound (US) and magnetic resonance imaging (MRI) are currently used during follow-up to detect recurrent disease. Unfortunately, in a relevant percentage of cases all of these traditional imaging techniques provide a significant number of doubtful/equivocal results or turn out negative even in presence of elevated Ca125 levels. Aim of our study was to evaluate sensitivity, specificity and accuracy of (18)F-FDG PET/CT in a group of patients with suspicion of ovarian cancer recurrence.

METHODS

We prospectively evaluated 41 patients with a mean age of 59.4 years who had been previously treated for ovarian cancer with surgery and radio-chemotherapy or radio-chemotherapy alone. Following the performance of traditional radiologic imaging (US, CT, MRI) and Ca125 measurement, all patients underwent additional (18)F-FDG PET/CT. PET/CT results were compared with histologic findings or clinical, laboratory and repeated traditional imaging techniques during subsequent follow-up data.

RESULTS

Of 41 patients 32 had a positive PET-CT (30 true positive, two false positive) whereas nine a negative PET/CT (five true negative, four false negative). Overall, in our experience (18)F-FDG PET/CT provided a good sensitivity (88.2%), specificity (71.4%) and accuracy (85.4%), superior to that reported in literature for traditional radiologic imaging.

CONCLUSIONS

It can be concluded that (18)F-FDG PET/CT appears to be a useful and accurate tool in disclosing early recurrent ovarian cancer.

Imaging and Cancer: Research Strategy of the American College of Radiology Imaging Network

The American College of Radiology Imaging Network (ACRIN) is a cooperative group funded by the National Cancer Institute and dedicated to developing and conducting clinical trials of diagnostic imaging and image-guided treatment technologies. ACRIN's six disease site committees are responsible for developing scientific strategies and resultant trials within the framework of ACRIN's five key hypotheses: (a) Screening and early detection with imaging can reduce cancer-specific mortality. (b) Less invasive image-guided therapeutic methods can reduce the mortality and morbidity associated with treating cancer. (c) Molecular-based physiologic and functional imaging can improve the diagnosis and staging of cancer, thus improving treatment. (d) Functional imaging can portray the effectiveness of treatment earlier and more accurately, thus reducing mortality and improving the likelihood of a cure. (e) Informatics and other "smart systems" can improve the evaluation of patients with cancer, thus leading to better and more effective treatments. This article details ACRIN's research strategy according to disease site through the year 2007.

[Oncologic screening with whole-body MRI: possibilities and limitations]

In the last decade the interest in radiological screening examination increased among informed laymen enormously. Independent from the evidence of whole-body examinations for cancer prevention the discussion about screening must again be considered again due to the newest technical developments, since MRI of the whole-body with high spatial resolution is feasible now within one single examination. The newest system permits simultaneous connection of up to 76 coil elements and signal reception from 32 independent receiving channels. Whole-body MRI including magnetic resonance colonography (MRC) is feasible within 60 min. In this review potential investigation protocols will be presented. Potentials, challenges and limitations of whole-body MRI in the prevention of the malignancies most frequently leading to death are discussed on the basis own experiences examples and the literature.

Mimics of Renal Colic: Alternative Diagnoses at Unenhanced Helical CT

During the past decade, unenhanced computed tomography (CT) has become the standard of reference in the detection of urinary calculi owing to its high sensitivity (>95%) and specificity (>98%) in this setting. Numerous diseases may manifest as acute flank pain and mimic urolithiasis. Up to one-third of unenhanced CT examinations performed because of flank pain may reveal unsuspected findings unrelated to stone disease, many of which can help explain the patient's condition. Alternative diagnoses are most commonly related to gynecologic conditions (especially adnexal masses) and nonstone genitourinary disease (eg, pyelonephritis, renal neoplasm), closely followed by gastrointestinal disease (especially appendicitis and diverticulitis). Hepatobiliary, vascular, and musculoskeletal conditions may also be encountered. Vascular causes of acute flank pain must always be considered, since these constitute life-threatening emergencies that may require the intravenous administration of contrast material for diagnosis. Radiologists must be familiar with the typical findings of urinary stone disease at unenhanced CT, as well as the spectrum of alternative diagnoses that may be detected with this modality, to accurately diagnose the source of flank pain.