From the archives of the AFIP: radiologic staging of ovarian carcinoma with pathologic correlation

18F-fluorodeoxyglucose positron emission tomography findings of peripheral nerve sheath tumour of the nasal cavity in a dog

An 8-year-old Miniature Poodle presented with chronic sneezing and unilateral epistaxis. A left-sided intranasal mass was identified on computed tomography. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) was performed to evaluate the metabolic activity of the mass. The intranasal mass showed mildly increased 18F-FDG uptake. The maximal and mean standardized uptake values (SUVs) of the mass were 3.4 and 2.6, respectively. The maximal SUV of the mass/mean SUV of the normal liver was 2.5. The 7-cm soft, pink mass was easily removed through rhinoscopy, with subsequent dramatic improvement in clinical signs. Histopathological and immunohistochemical analyses determined that the mass was an intermediate-grade malignant peripheral nerve sheath tumour (PNST). This is the first report of 18F-FDG PET findings in a PNST in dogs.

Extramedullary Hematopoiesis: A Forgotten Diagnosis and a Great Mimicker of Malignancy

ABSTRACT

Radiology errors have been reported in up to 30% of cases when patients have abnormal imaging findings. Although more than half of errors are failures to detect critical findings, over 40% of errors are when findings are recognized but the correct diagnosis or interpretation is not made. One common source of error is when imaging findings from one process simulate imaging findings from another process but the correct diagnosis is not made. This can result in additional imaging studies, unnecessary biopsies, or surgery. Extramedullary hematopoiesis is one of those uncommon disease processes that can produce many imaging findings that may lead to misdiagnosis. The objective of this article is to review the common and uncommon imaging features of extramedullary hematopoiesis while presenting a series of interesting relevant illustrative cases with emphasis on CT.

Implications of peritoneal cancer index distribution on patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Objectives

Peritoneal cancer index (PCI) score is a common prognostication tool in peritoneal metastases (PM). We hypothesize that the distribution of PCI score and involvement of specific regions affects survival and morbidity outcomes.

Methods

Data was collected from a prospective database of patients who underwent CRS and HIPEC for PM at the National Cancer Centre Singapore. We evaluate the relationship between PCI, PCI distribution, and survival and morbidity outcomes.

Results

One hundred and fifty-two patients underwent CRS and HIPEC with a median PCI score of nine (range 0–31). Median overall survival (OS) and progression free survival (PFS) were 43 and 17 months, respectively. Region six (pelvis) was most commonly involved and had the highest frequency of heavy disease burden. Presence of PM in the lower abdomen, flanks, and small bowel were associated with poorer OS (p=0.01, 0.03, <0.001) and PFS (p=0.04, 0.02, <0.001). Involvement of porta hepatitis predicted poorer OS but not PFS (p=0.03). Involvement of the gastric antrum resulted in higher rates of postoperative complications.

Conclusions

The pattern of PCI distribution may be associated with varying survival and morbidity outcomes.

CT imaging of peritoneal carcinomatosis with surgical correlation: a pictorial review

Cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy has revolutionized the survival and the quality of life in selected patients with peritoneal carcinomatosis. Preoperative CT is important for the selection of patients that may benefit from cytoreductive surgery and is useful for surgical planning. There are several tasks for the radiologist during CT interpretation: to describe cancerous implants on a "site-by-site" basis in the peritoneum, ligaments, mesenteries and visceral surfaces, to analyze patterns of involvement and to estimate the disease burden. Knowledge of the correlation between the CT and the surgical findings enhances the understanding of the disease and facilitates the communication between radiologists and surgeons.

Are CT and MRI useful tools to distinguish between micropapillary type and typical type of ovarian serous borderline tumors?

PURPOSE

To investigate the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of ovarian serous borderline tumors (SBTs), and evaluate whether CT and MRI can be used to distinguish micropapillary from typical subtypes.

MATERIALS AND METHODS

We retrospectively reviewed the clinical features and CT and MR imaging findings of 47 patients with SBTs encountered at our institute from September 2013 to December 2019. 30 patients with 58 histologically proven typical SBT and 17 patients with 26 micropapillary SBT were reviewed. Preoperative CT and MR images were evaluated, by two observers in consensus for the laterality, maximum diameter (MD), morphology patterns, internal architecture, attenuation or signal intensity, ADC value, enhancement patterns of solid portions (SP), and extra-ovarian imaging features.

RESULTS

The median age were similar between typical SBT and SBT-MP (32.5 years, 36 years, respectively, P>0.05). Morphology patterns between two subtypes were significantly different on CT and MR images (P < 0.001). Irregular solid tumor (21/37, 56.76%) was the major morphology pattern of typical SBT tumor, while unilocular cyst with mural nodules (14/20, 70%) was the major morphology pattern of SBT-MP on CT images. Similarly, papillary architecture with internal branching (PA&IB) (17/21, 80.95%) was the major morphology pattern of typical SBT tumor, while unilocular cyst with mural nodules (4/6, 66.67%) was the major pattern of SBT-MP on MR images. PA&IB all showed slightly hyperintense papillary architecture with hypointense internal branching on T2-weighted MRI. More calcifications were found in typical SBT (24/37, 64.86%) than SBT-MP mass lesion (6/20, 30%) (P < 0.05). Hemorrhage was less frequently visible in (20/37, 54.05%) typical SBT lessons than SBT-MP mass lesion (18/20, 90%) (P < 0.05). The ovarian preservation is more seen in typical SBT (38/58, 65.52%) than SBT-MP (12/28, 42.86%) in our series (P < 0.05). Mean ADC value of solid portions (papillary architecture and mural nodules) was 1.68 (range from 1.44 to 1.85) × 10^-3 mm²/s for typical SBT and 1.62 (range from 1.45 to 1.7) × 10^-3 mm²/s for that of SBT-MP. The solid components of the two SBT subtypes showed wash-in appearance enhancements after contrast injection both in CT and MR images except 2 of SBT-MP with no enhancement as complete focal hemorrhage on MR images.

CONCLUSION

Morphology and internal architecture are two major imaging features that can help to distinguish between SBT-MP and typical SBT.

Imaging in gynecological disease (17): ultrasound features of malignant ovarian yolk sac tumors (endodermal sinus tumors)

OBJECTIVE

To describe the clinical and sonographic characteristics of malignant ovarian yolk sac tumors (YSTs).

METHODS

In this retrospective multicenter study, we included 21 patients with a histological diagnosis of ovarian YST and available transvaginal ultrasound images and/or videoclips and/or a detailed ultrasound report. Ten patients identified from the International Ovarian Tumor Analysis (IOTA) studies had undergone a standardized preoperative ultrasound examination, by an experienced ultrasound examiner, between 1999 and 2016. A further 11 patients were identified through medical files, for whom ultrasound images were retrieved from local image workstations and picture archiving and communication systems. All tumors were described using IOTA terminology. The collected ultrasound images and videoclips were used by two observers for additional characterization of the tumors.

RESULTS

All cases were pure YSTs, except for one that was a mixed tumor (80% YST and 20% embryonal carcinoma). Median age at diagnosis was 25 (interquartile range (IQR), 19.5-30.5) years. Seventy-six percent (16/21) of women had an International Federation of Gynecology and Obstetrics (FIGO) Stage I-II tumor at diagnosis. Fifty-eight percent (11/19) of women felt pain during the ultrasound examination and one presented with ovarian torsion. Median serum α-fetoprotein (S-AFP) level was 4755 (IQR, 1071-25 303) µg/L and median serum CA 125 level was 126 (IQR, 35-227) kU/L. On ultrasound assessment, 95% (20/21) of tumors were unilateral. The median maximum tumor diameter was 157 (IQR, 107-181) mm and the largest solid component was 110 (IQR, 66-159) mm. Tumors were classified as either multilocular-solid (10/21; 48%) or solid (11/21; 52%). Papillary projections were found in 10% (2/21) of cases. Most (20/21; 95%) tumors were well vascularized (color score, 3-4) and none had acoustic shadowing. Malignancy was suspected in all cases, except in the patient with ovarian torsion, who presented a tumor with a color score of 1, which was classified as probably benign. Image and videoclip quality was considered as adequate in 18/21 cases. On review of the images and videoclips, we found that all tumors contained both solid components and cystic spaces, and that 89% (16/18) had irregular, still fine-textured and slightly hyperechoic solid tissue, giving them a characteristic appearance.

CONCLUSION

Malignant ovarian YSTs are often detected at an early stage, in young women usually in the second or third decade of life, presenting with pain and markedly elevated S-AFP. On ultrasound, malignant ovarian YSTs are mostly unilateral, large and multilocular-solid or solid, with fine-textured slightly hyperechoic solid tissue and rich vascularization. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology..

Imaging in pediatric ovarian tumors

The spectrum of ovarian tumors in the pediatric population differs significantly from that in adults. Germ cell tumors are the predominant class of ovarian tumors in children, whereas epithelial tumors are the most common in adults. Ultrasonography is the modality of choice for the initial evaluation of pediatric ovarian tumors. Determining the diagnosis based on imaging may prove difficult, and combining the imaging findings with the clinical scenario is very helpful in reaching a differential diagnosis during clinical practice. We will discuss the spectrum of ovarian neoplasms in the pediatric population and describe their clinical, pathologic, and imaging characteristics. A few unique entities related to ovarian tumors, such as growing teratoma syndrome, anti-N-methyl-D-aspartate receptor encephalitis, and hereditary ovarian tumor syndromes, are also discussed. In addition, we will review several entities that may mimic ovarian neoplasms as well as their distinct imaging features.

P.R.O.P.S. - A novel Pre-Operative Predictive Score for unresectability in patients with colorectal peritoneal metastases being considered for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC)

Background

Twenty to thirty percent of planned cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS and HIPEC) procedures are abandoned intra-operatively. Pre-operative factors associated with unresectability identified previously were used to develop a Pre-Operative Predictive Score (PROPS), which was compared with current selection criteria—Peritoneal Surface Disease Severity Score (PSDSS), Verwaal’s Prognostic Score (PS) and Colorectal Peritoneal Metastases Prognostic Surgical Score (COMPASS), to determine which score provides the best prediction for unresectability.

Methods

Fifty-six patients with peritoneal metastases of colorectal origin were included. Beta-coefficient values of significant variables (p < 0.05) were determined from multivariate analysis to develop PROPS. PROPS, PSDSS, PS and COMPASS were compared using a receiver operating characteristic curve to calculate its accuracy, sensitivity and specificity.

Results

PROPS consisted of nine patient and tumour factors which were categorised into three groups: (i) poor tumour biology: previous inadequate resection, underwent multiple lines of chemotherapy and poorly differentiated or signet cell histology; (ii) heavy tumour burden: abdominal distension, palpable abdominal mass and computed tomography findings of ascites, small bowel disease and/or omental thickening; and (iii) active tumour proliferation: elevated tumour markers. Overall, PROPS achieved 86% accuracy with 100% sensitivity and 68% specificity, PSDSS achieved 85% accuracy with 100% sensitivity and 63% specificity, PS achieved 73% accuracy with 100% sensitivity and 68% specificity and COMPASS achieved 61% accuracy with 27% sensitivity and 100% specificity.

Conclusions

PROPS is more effective in predicting unresectability as compared to PSDSS, PS and COMPASS, and has the added advantage of using solely pre-operative factors.

ACR Appropriateness Criteria® Staging and Follow-Up of Ovarian Cancer

In the management of epithelial ovarian cancers, imaging is used for cancer detection and staging, both before and after initial treatment. The decision of whether to pursue initial cytoreductive surgery for ovarian cancer depends in part on accurate staging. Contrast-enhanced CT of the abdomen and pelvis (and chest where indicated) is the current imaging modality of choice for the initial staging evaluation of ovarian cancer. Fluorine-18-2-fluoro-2-deoxy-d-glucose PET/CT and MRI may be appropriate for problem-solving purposes, particularly when lesions are present on CT but considered indeterminate. In patients who achieve remission, clinical suspicion for relapse after treatment prompts imaging evaluation for recurrence. Contrast-enhanced CT is the modality of choice to assess the extent of recurrent disease, and fluorine-18-2-fluoro-2-deoxy-d-glucose PET/CT is also usually appropriate, as small metastatic foci may be identified. If imaging or clinical examination confirms a recurrence, the extent of disease and timing of disease recurrence then determines the choice of treatments, including surgery, chemotherapy, and radiation therapy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Imaging strategy in recurrent ovarian cancer: a practical review

Ovarian cancer is one of the most aggressive gynaecologic malignancies in women worldwide. The lack of proper screening programs and the characteristic abdominal spreading with minimal clinical symptoms give rise of its high lethality. Most patients show advanced disease at diagnosis and have a poor prognosis. The surveillance of ovarian cancer patients after initial treatment is a challenging question in clinical practice and there is no consensus in literature about the most appropriate follow-up strategy for these women. The role of Imaging has become increasingly important, allowing to properly monitor patients, distinguishing the different relapse patterns, thus guiding the correct management and therapy. In this review, we report and analyze the scientific evidence about the role of the different imaging modalities now available in the follow-up strategy and management of Epithelial Ovarian Cancer patients with recurrent disease.

Imaging in the pre-operative staging of ovarian cancer

The main prognostic factor in ovarian cancer is the stage of disease at diagnosis. The staging system in use (FIGO classification, updated in 2014) is based on the surgical-pathological findings. Although surgical staging is the gold standard in ovarian cancer, the initial patient management depends on the imaging-based pre-surgical staging assessment, in order to identify unresectable or difficult to resect disease. Radiologists need to be aware of the strengths of the available imaging modalities, as well as the imaging pitfalls. Clear understanding of pattern of disease spread and review areas are critical for accurate staging and treatment planning. The current standard of care for pre-surgical staging is CT of the thorax, abdomen, and pelvis. This allows a rapid evaluation of disease extent and is fairly accurate in identifying bulky disease but has definite limitations in assessing the extent of small volume disease and in the confirmation of certain sites of disease beyond the abdomen. Functional MRI has been reported to be superior in detecting small peritoneal deposits. PET/CT may be used as a problem-solving tool in some patients where determination remains unclear, particularly in confirmation of advanced stage beyond the abdomen.

Low-grade epithelial ovarian cancer: what a radiologist should know

Ovarian cancer accounts for the death of over 100,000 females every year and is the most lethal gynecological malignancy. Low-grade serous ovarian carcinoma (LGSOC) and high-grade serous ovarian carcinoma (HGSOC) have been found to represent two distinct entities based on their molecular differences, clinical course, and response to chemotherapy. Currently, all ovarian cancers are staged according to the revised staging system of the International Federation of Gynecology and Obstetrics (FIGO). Imaging plays an integral role in the diagnosis, staging, and follow-up of ovarian cancers. This review will be based on the two-tier grading system of epithelial ovarian cancers, with the main emphasis on serous ovarian cancer, and the role of imaging to characterize low-grade vs high-grade tumors and monitor disease recurrence during follow-up.

The role of FDG-PET/CT in gynecologic imaging: an updated guide to interpretation and challenges

All women, during their lifetime, are at risk of developing some form of gynecologic malignancy. The role of FDG-PET/CT has become more established in the management of gynecologic malignancies in the last decade. In this article, we will review the role of FDG-PET/CT in endometrial, cervical, ovarian, and vaginal cancer, by highlighting its strengths and limitations. While the role in initial or pre-operative staging for FDG-PET/CT is controversial, it allows noninvasive detection of equivocal or distant metastases, may alter stage and prognosis, and can guide or help eliminate unnecessary interventions that may not be beneficial. FDG-PET/CT is a useful adjunct to traditional staging with MR and CT.

Peritoneal Carcinomatosis in Primary Ovarian Cancer: Ultrasound Detection and Comparison with Computed Tomography

We retrospectively compared detection rates and consistency for diagnosis of peritoneal carcinomatosis (PC) of primary ovarian cancer (OC) between ultrasound (US) and computed tomography (CT) scans in 41 patients whose PC of OC (stages IIC-IV) had been diagnosed by histopathology findings. Compared with CT detection rates, those for US were significantly higher for metastases to the pelvic area (92.3% vs. 43.6%, p < 0.001) and bowel surface (64.0% vs. 16.0%, p = 0.002); however, they did not significantly differ for other sites: omentum, diaphragm, lateral peritoneum, mesenteric, hepatic and splenic surfaces. Diagnostic consistency between US and CT scans were fair to moderate for splenic (κ = 0.806), hepatic (κ = 0.485), lateral peritoneum (κ = 0.450) and diaphragm (κ = 0.338) surfaces, but poorly consistent for other parts (κ = 0.144-0.229). In summary, US can complement CT scans, especially for detecting PC of primary OC metastases in pelvic and bowel surfaces.

Role of Imaging in Peritoneal Surface Malignancies

Imaging plays a vital role in the evaluation of peritoneal malignancies. The presence of peritoneal metastases (PM) alters tumor staging, with direct implications in treatment choice and prognosis. Cytoreductive surgery (CRS) and Hyperthermic intraperitoneal chemotherapy (HIPEC) as a combined modality treatment have led to prolonged survival and even cure in selected patients with PM. Better outcomes are seen in patients with limited disease spread. Therefore, early diagnosis of peritoneal tumor seeding is essential. Despite significant advancement of technology, assessment of the origin of PM is often difficult, due partly to the complex peritoneal anatomy and partly due to the complex overlap of imaging features. Multidetector CT (MDCT) is the main stay due to its wide availbility, rapid evaluation, robust technique and good resolution. Imaging plays a vital role in selecting patients for the combined modality treatment. MRI is not as popular as CT due to limited availability, time required for the study and lack of experience with interpreting the results. PET-CT is useful in ruling out extra peritoneal disease and it is the CT component that is more reliable for predicting the disease extent. This article reviews the current use of various imaging modalities in various stages of treatment of patients with PM especially those undergoing CRS and HIPEC.

HE4 in the differential diagnosis of ovarian masses

Ovarian masses, a common finding among pre- and post-menopausal women, can be benign or malignant. Ovarian cancer is the leading cause of death from gynecologic malignancy among women living in industrialized countries. According to the current guidelines, measurement of CA125 tumor marker remains the gold standard in the management of ovarian cancer. Recently, HE4 has been proposed as emerging biomarker in the differential diagnosis of adnexal masses and in the early diagnosis of ovarian cancer. Discrimination of benign and malignant ovarian tumors is very important for correct patient referral to institutions specialized in care and management of ovarian cancer. Tumor markers CA125 and HE4 are currently incorporated into the "Risk of Ovarian Malignancy Algorithm" (ROMA) with menopausal status for discerning malignant from benign pelvic masses. The availability of a good biomarker such as HE4, closely associated with the differential and early diagnosis of ovarian cancer, could reduce medical costs related to more expensive diagnostic procedures. Finally, it is important to note that HE4 identifies platinum non-responders thus enabling a switch to second line chemotherapy and improved survival.

Ovarian malignant germ cell tumors: cellular classification and clinical and imaging features

Ovarian malignant germ cell tumors (OMGCTs) are heterogeneous tumors that are derived from the primitive germ cells of the embryonic gonad. OMGCTs are rare, accounting for about 2.6% of all ovarian malignancies, and typically manifest in adolescence, usually with abdominal pain, a palpable mass, and elevated serum tumor marker levels, which may serve as an adjunct in the initial diagnosis, monitoring during therapy, and posttreatment surveillance. Dysgerminoma, the most common malignant germ cell tumor, usually manifests as a solid mass. Immature teratomas manifest as a solid mass with scattered foci of fat and calcifications. Yolk sac tumors usually manifest as a mixed solid and cystic mass. Capsular rupture or the bright dot sign, a result of increased vascularity and the formation of small vascular aneurysms, may be present. Embryonal carcinomas and polyembryomas rarely manifest in a pure form and are more commonly part of a mixed germ cell tumor. Some OMGCTs have characteristic features that allow a diagnosis to be confidently made, whereas others have nonspecific features, which make them difficult to diagnose. However, imaging features, the patient's age at presentation, and tumor markers may help establish a reasonable differential diagnosis. Malignant ovarian germ cell tumors spread in the same manner as epithelial ovarian neoplasms but are more likely to involve regional lymph nodes. Preoperative imaging may depict local extension, peritoneal disease, and distant metastases. Suspicious areas may be sampled during surgery. Because OMGCTs are almost always unilateral and are chemosensitive, fertility-sparing surgery is the standard of care.

Algorithmic approach to solid adnexal masses and their mimics: utilization of anatomic relationships and imaging features to facilitate diagnosis

Solid adnexal masses, while less common than their cystic counterparts, may present a challenge for radiologists given the wide range of histologic entities that occur in this region. Pelvic masses, especially when large, can seem overwhelming at first but application of an algorithmic approach allows for more confident assessment. This approach focuses first on the use of anatomic relationships and interactions of various pelvic structures to localize the mass' origin. For instance, the directionality of ureteral displacement can suggest if a mass is intra or extraperitoneal. Then, key discriminating imaging features, such as the presence of fat, hypervascularity, or low T2 signal on magnetic resonance imaging (MRI) can be applied to further narrow the list of diagnostic possibilities. Entities such as leiomyomas, nerve sheath tumors, congenital uterine anomalies, and vascular abnormalities (ovarian torsion or iliac vessel aneurysm) in particular are often accurately characterized with sonography and/or MRI. For solid adnexal masses in which a definitive diagnosis by imaging is not reached, information germane to clinicians regarding further management can still be provided, principally with regard to surgical vs. nonsurgical treatment.

The effectiveness of dual-phase 18F-FDG PET/CT in the detection of epithelial ovarian carcinoma: a pilot study

Background

The aim of our study is to establish the potential role of dual-phase ¹⁸F-fluorodeoxyglucose positron emission tomography / computed tomography (FDG-PET/CT) in patients presenting ovarian masses with diffuse peritoneal infiltration for differentiating benign from malignant lesions.

Methods

Twenty patients (13 with ovarian cancers and 7 with benign lesions) were evaluated preoperatively by dual-phase ¹⁸F-FDG-PET/CT performed 1 h and 2 h after injection of ¹⁸F-FDG. The maximum standardized uptake value (SUV_max) for both time points SUV_max1 and SUV_max2 were determined, respectively, and the retention index (RI) was calculated by subtracting the SUV_max1 from the SUV_max2 and dividing by SUV_max1.

Results

The areas under the receiver operating characteristic curves (AUCs) of SUV_max1 and SUV_max2 were 0.753 (P = 0.062, 95% confidence interval [CI] = 0.512–0.915) and 0.835 (P = 0.001, 95% CI = 0.604–0.961), respectively. The AUC of the RI was 0.901 (P < 0.001, 95% CI = 0.684–0.988). Using pairwise comparisons, the AUC of SUV_max2 was significantly higher than that of SUV_max1 (P = 0.032). The AUC of the RI was higher than those of SUV_max1 and SUV_max2, but the difference was not statistically significant.

Conclusion

Dual-phase ¹⁸F-FDG PET/CT might be considered when preoperative imaging is indeterminate. A larger-scaled, prospective study is needed to verify these results.

Pelvic Ultrasound Simulation Training Models and Case Scenarios

Pelvic ultrasound simulation training using high-fidelity mannequins can provide a safe and controlled learning environment to foster the ultrasound education of medical students, residents and faculty. The instruction can be tailored to the specific needs of the learners. Topics for instruction range from teaching basic anatomy and ultrasound scanning techniques to common and advanced obstetrics and gynecology disease presentations and pathological processes. Simulation can closely approximate patient encounters using case based scenarios which will aid in developing knowledge and skills that can be transferred to the clinical environment. The goal of simulation is to help the learners to become more confident and competent to care for their patients.

How to cite this article

Sarmiento J, Stewart K, Aguila J, Bagherpour A, Kupesic Plavsic S. Pelvic Ultrasound Simulation Training Models and Case Scenarios. Donald School J Ultrasound Obstet Gynecol 2014;8(1):22-30.

Gynecologic tumors: how to communicate imaging results to the surgeon

Gynecologic cancers are a leading cause of morbidity and mortality for female patients, with an estimated 88,750 new cancer cases and 29,520 deaths in the United States in 2012. To offer the best treatment options to patients it is important that the radiologist, surgeon, radiation oncologist, and gynecologic oncologist work together with a multidisciplinary approach. Using the available diagnostic imaging modalities, the radiologist must give appropriate information to the surgeon in order to plan the best surgical approach and its timing.

The special role of ultrasound for screening, staging and surveillance of malignant ovarian tumors: distinction from other methods of diagnostic imaging

Ovarian cancer is the most aggressive gynecologic malignancy, with a 5-year survival rate ranging around 40%. A crucial factor influencing the prognosis is early detection of a suspicious mass and referral to a gynecologic oncology center for further diagnosis, staging and debulking surgery. Here, we present the different imaging methods ultrasound (US), magnetic resonance imaging, computer tomography (CT) and 18F-fluoro-deoxyglucose positron emission tomography (PET)/CT that are used for the characterization, diagnosis, staging and surveillance of ovarian cancer. In this review, we focus on US and discuss in detail the advantages and the limitations, as well as the appropriate indications for each of the individual imaging techniques.

Ovarian masses: is multi-detector computed tomography a reliable imaging modality?

BACKGROUND

Ovarian cancer continues to pose a major challenge to physicians and radiologists. It is the third most common gynecologic malignancy and estimated to be fifth leading cancer cause of death in women, constituting 23% of all gynecological malignancies. Multi-detector computed tomography (MDCT) appears to offer an excellent modality in diagnosing ovarian cancer based on combination of its availability, meticulous technique, efficacy and familiarity of radiologists and physicians. The aim of this study was to compute sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of 64- slice MDCT in classifying ovarian masses; 95% confidence intervals were reported.

MATERIALS AND METHODS

We prospectively designed a cross-sectional analytical study to collect data from July 2010 to August 2011 from a tertiary care hospital in Karachi, Pakistan. A sample of 105 women aged between 15-80 years referred for 64-MDCT of abdomen and pelvis with clinical suspicion of malignant ovarian cancer, irrespective of stage of disease, were enrolled by non- probability purposive sampling. All patients who were already known cases of histologically proven ovarian carcinoma and having some contraindication to radiation or iodinated contrast media were excluded.

RESULTS

Our prospective study reports sensitivity, specificity; positive and negative predictive values with 95%CI and accuracy were computed. Kappa was calculated to report agreement among the two radiologists. For reader A, MDCT was found to have 92% (0.83, 0.97) sensitivity and 86.7% (0.68, 0.96) specificity, while PPV and NPV were 94.5% (0.86, 0.98) and 86.7% (0.63, 0.92), respectively. Accuracy reported by reader A was 90.5%. For reader B, sensitivity, specificity, PPV and NPV were 94.6% (0.86, 0.98) 90% (0.72, 0.97) 96% (0.88, 0.99) and 87.1% (0.69, 0.95) respectively. Accuracy computed by reader B was 93.3%. Excellent agreement was found between the two radiologists with a significant kappa value of 0.887.

CONCLUSION

Based on our study results, we conclude MDCT is a reliable imaging modality in diagnosis of ovarian masses accurately with insignificant interobserver variability.

Patterns of peritoneal spread of tumor in the abdomen and pelvis

The spread of tumor in the peritoneum can be understood, although it is a complex organ. A study of its embryology, anatomy and function is of clear benefit. It is formed from a network of folds, reflections, and potential spaces produced by the visceral and parietal peritoneum. These folds and reflections begin as a dorsal and ventral mesentery, supporting the primitive gut in early embryologic development. The dorsal mesentery connects the stomach and other organs to the posterior abdominal wall, while the ventral mesentery connects the stomach to the ventral abdominal wall. As the embryo develops, there is further organ growth, elongation, cavitation and rotation. The dorsal and ventral mesentery also develops along with the viscera, forming ligaments, mesenteries, omenta and potential spaces from the resulting reflections and folds. These ligaments, mesenteries, and omenta, support and nurture the organs of the peritoneum, providing a highway for arteries, veins, nerves and lymphatics. The potential spaces created from these folds and reflections of the visceral and parietal peritoneum are also important to realize. For example, the transverse mesocolon divides the peritoneal cavity into a supramesocolic and inframesocolic space in the abdomen and paravesicular spaces within the pelvis. The falciform ligament is well known in the supramesocolic space, dividing it further into a left and right compartment. Knowledge of the peritoneal vascular anatomy is beneficial in locating the spaces and ligaments about the peritoneum. For example, identifying the left gastric artery or vein will lead to the gastrohepatic ligament, which is part of the supramesocolic space. Besides serving a life sustaining role, the multiple compartments, ligaments, mesenteries and omenta within the peritoneum can also facilitate the spread of disease. Tumors can spread directly from one organ to another, seed metastatic deposits in the peritoneal cavity, and travel through the lymphatic or hematogenous route to invade other organs in the peritoneum.

Multimodality imaging of ovarian cystic lesions: Review with an imaging based algorithmic approach

Ovarian cystic masses include a spectrum of benign, borderline and high grade malignant neoplasms. Imaging plays a crucial role in characterization and pretreatment planning of incidentally detected or suspected adnexal masses, as diagnosis of ovarian malignancy at an early stage is correlated with a better prognosis. Knowledge of differential diagnosis, imaging features, management trends and an algorithmic approach of such lesions is important for optimal clinical management. This article illustrates a multi-modality approach in the diagnosis of a spectrum of ovarian cystic masses and also proposes an algorithmic approach for the diagnosis of these lesions.

Role of sonography in the diagnostic workup of ovarian and adnexal masses except in pregnancy and during ovarian stimulation

The main role of imaging is to provide a description of the appearance, size, and location of adnexal lesions and associated abnormalities. In some circumstances, the aggressive potential of an adnexal lesion may be suggested on the basis of the imaging findings, the age of the patient, and the clinical data.

HE4 combined with MDCT imaging is a good marker in the evaluation of disease extension in advanced epithelial ovarian carcinoma

The purpose of the study was to evaluate the expression of the biomarkers CA125 and HE4 combined with imaging, in patients with advanced epithelial ovarian cancer (EOC). Forty-six women with EOC were included in the study all affected with peritoneal carcinomatosis. Twenty-two of 46 patients (group I) had peritoneal carcinomatosis with small implants in single or in multiple sites (score 1); 24/46 patients (group II) had macro-nodular implants and omental thickening (score 2). High levels of CA125 (350 ± 11, mean ± SEM) have been observed in 21/22 patients of group I, and a similar value (370 ± 13) has been observed in all patients belonging to group II. HE4 positivity values (350 ± 9) have been observed in all group I patients, whereas all patients belonging to group II showed a higher value of HE4 (600 ± 12). Statistically significant differences were observed between the HE4 levels observed in group I patients in comparison with group II patients (p < 0.0001). In addition, we expressed the extension of lymph nodal disease in three scores: L1-L2-L3, and a statistically significant correlation was observed between high HE4 levels and severity of lymph nodal disease L3 (p < 0.0001). The availability of biomarkers, particularly HE4, together with sophisticated imaging techniques, strengthens the clinical relevance of this study, for the follow-up of patients with peritoneal carcinomatosis.

Ovarian cancer: detection and radiologic staging

Ovarian cancer is the second most common gynecologic malignancy. It is the deadliest, largely owing to late stage at the time of diagnosis. Ultrasound is modality of choice in the evaluation of suspected adnexal masses. Magnetic resonance imaging is an excellent problem solver when an adnexal mass is indeterminate on ultrasound. Staging of ovarian cancer remains surgical, though preoperative imaging can identify inoperable patients and identify suspicious sites for intraoperative biopsy. This article reviews the use of different imaging modalities in the detection and staging of ovarian carcinoma, and discusses imaging indications, radiologic features, and the shortcomings of imaging.

CT, MRI and PET imaging in peritoneal malignancy

Imaging plays a vital role in the evaluation of patients with suspected or proven peritoneal malignancy. Nevertheless, despite significant advances in imaging technology and protocols, assessment of peritoneal pathology remains challenging. The combination of complex peritoneal anatomy, an extensive surface area that may host tumour deposits and the considerable overlap of imaging appearances of various peritoneal diseases often makes interpretation difficult. Contrast-enhanced multidetector computed tomography (MDCT) remains the most versatile tool in the imaging of peritoneal malignancy. However, conventional and emerging magnetic resonance imaging (MRI) and positron emission tomography (PET)/CT techniques offer significant advantages over MDCT in detection and surveillance. This article reviews established and new techniques in CT, MRI and PET imaging in both primary and secondary peritoneal malignancies and provides an overview of peritoneal anatomy, function and modes of disease dissemination with illustration of common sites and imaging features of peritoneal malignancy.

Intraperitoneal treatment with the trifunctional bispecific antibody Catumaxomab in patients with platinum-resistant epithelial ovarian cancer: a phase IIa study of the AGO Study Group

OBJECTIVE

The aim of this study was to select the best catumaxomab regimen for further investigation in ovarian cancer based on confirmed tumour response.

METHODS

Randomised open-label phase IIa study in women with platinum-resistant or -refractory epithelial ovarian cancer. Catumaxomab (6-hour intraperitoneal infusion on days 0, 3, 7 and 10) was administered at a low (10, 10, 10 and 10 μg) or high dose (10, 20, 50 and 100 μg). Responders were patients with either a complete (CR) or partial (PR) response.

RESULTS

Forty-five patients were randomised to receive either low dose (23) or high dose (22). There were no responders in the low-dose versus one patient (5%) in the high-dose group with a PR. In the low-dose group, two patients (9%) had stable disease compared with five patients (23%) in the high-dose group. Catumaxomab was well tolerated and there was no difference between the dose groups in the incidence of treatment-induced adverse events, the most common of which were gastrointestinal and injection-site reactions.

CONCLUSION

Catumaxomab had modest activity in platinum-resistant ovarian cancer. The high-dose regimen was associated with a slightly better therapeutic index than the low dose regimen.

Role of multidetector computed tomography (MDCT) in patients with ovarian masses

Objective:

To evaluate the diagnostic accuracy of multidetector 64-slice computed tomography (MDCT) in the diagnosis and differentiation of benign and malignant ovarian masses using histopathology and surgical findings as the gold standard.

Material and methods:

This study was conducted in Aga Khan University Hospital, Karachi, Pakistan. Data was reviewed retrospectively from 1 November 2008 to 12 December 2009. One hundred patients found to have ovarian masses on CT scan were included in the study. CT scan was performed in all these patients after administration of oral and IV contrast. Ovarian masses were classified as benign and malignant on scan findings. Imaging findings were compared with histopathologic results and surgical findings. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of MDCT were calculated.

Results:

MDCT was found to have 97% sensitivity, 91% specificity, and an accuracy of 96% in the differentiation of benign and malignant ovarian masses, while PPV and NPV were 97% and 91%, respectively.

Conclusion:

MDCT imaging offers a safe, accurate and noninvasive modality to differentiate between benign and malignant ovarian masses.

Radiological staging of ovarian carcinoma

Ovarian cancer is the sixth most commonly diagnosed cancer in the world, accounting for 4% of all female cancers. An estimated 1 in 71 women in the United States will develop ovarian cancer in their lifetime. Accurate staging of ovarian carcinoma is vital in the appropriate management and counseling of patients. The surgical staging proposed by the International Federation of Obstetrics and Gynaecology is the most universally used, and International Federation of Obstetrics and Gynaecology encourages the use of imaging techniques to assess prognostic factors, such as resectable disease and lymph node status. Identifying the volume and locations of tumor is valuable in planning percutaneous tissue biopsy, triaging patients to either primary cytoreductive surgery, or primary platinum-based chemotherapy. Contrast-enhanced computed tomography is the modality of choice for the staging of ovarian carcinoma, with magnetic resonance imaging being used as a problem-solving tool. In this article we discuss and illustrate the staging of ovarian carcinoma, with emphasis on the current imaging modalities and optimal image acquisition.

MRI, CT, and PET/CT for ovarian cancer detection and adnexal lesion characterization

OBJECTIVE

The purpose of this article is to describe the role of MR, CT, and PET/CT in the detection of ovarian cancer and the evaluation of adnexal lesions.

CONCLUSION

The goal of imaging in ovarian cancer detection is to expeditiously distinguish benign adnexal lesions from those requiring further pathologic evaluation for malignancy. For lesions indeterminate on ultrasound, MRI increases the specificity of imaging evaluation, thus decreasing benign resections. CT is useful in diagnosis and treatment planning of advanced cancer. Although (18)F-FDG-avid ovarian lesions in postmenopausal women are considered suspicious for malignancy, PET/CT is not recommended for primary cancer detection because of high false-positive rates.

Peritoneal metastasis: detection with 16- or 64-detector row CT in patients undergoing surgery for gastric cancer

PURPOSE

To retrospectively measure the diagnostic performance of prospective computed tomographic (CT) results obtained by using 16- or 64-detector row scanners in the detection of peritoneal metastases (PMs) in patients with advanced gastric cancer.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived the need to obtain patient consent. In 498 patients with gastric cancer (stage >or= T2) who were undergoing surgery, the presence of PM was prospectively rated as grade 0 (absent), grade 1 (equivocal), or grade 2 (present) on CT scans (0.67 or 2 mm thick) that were interpreted by interactively adjusting the viewing thickness and viewing plane. The CT readings were retrospectively compared with surgical and pathologic findings. In patients in whom the presence of PM was rated as grade 1 or less, factors predictive of PM were identified by testing variables, including patient and tumor characteristics, with univariate tests and multivariate logistic regression analysis.

RESULTS

Fifty-three patients (10.6%) had confirmed PM. When only grade 2 was considered to indicate a positive CT reading, sensitivity and specificity were 28.3% (15 of 53) and 98.9% (440 of 445), respectively. With the threshold of grade 1 or greater indicating a positive reading, sensitivity and specificity were 50.9% (27 of 53) and 96.2% (428 of 445), respectively. In the patients with grades of 1 or less, the significant factors predictive of PM were greater tumor size and T stage.

CONCLUSION

The sensitivity of PM detection is limited, even with modern CT techniques. In patients whose CT results are not definitely positive for PM, staging laparoscopy is still recommended if the aforementioned two predictive factors (greater tumor size and T stage) are suspected.

Ovarian cancer: detection and radiologic staging

Ovarian cancer is the second most common gynecologic malignancy. It is the deadliest, largely owing to late stage at the time of diagnosis. Ultrasound is modality of choice in the evaluation of suspected adnexal masses. Magnetic resonance imaging is an excellent problem solver when an adnexal mass is indeterminate on ultrasound. Staging of ovarian cancer remains surgical, though preoperative imaging can identify inoperable patients and identify suspicious sites for intraoperative biopsy. This article reviews the use of different imaging modalities in the detection and staging of ovarian carcinoma, and discusses imaging indications, radiologic features, and the shortcomings of imaging.

Imaging of 186Re-liposome therapy in ovarian cancer xenograft model of peritoneal carcinomatosis

This study determined the biodistribution of rhenium-186 ((186)Re) encapsulated in biotin-liposomes containing patent blue dye, injected intraperitoneally (IP) with avidin in an OVCAR-3 ovarian cancer xenograft model and evaluated tumor response of this therapy with fluorine-18-fluorodeoxyglucose ((18)F-FDG) microPET imaging. Treated rats (n = 8) received an IP injection of (186)Re-blue-biotin-liposomes (1000 MBq/kg) 30 min before an IP injection of avidin (5 mg), whereas control rats (n = 4) received a sham IP injection of saline. Scintigraphic images showed that (186)Re-blue-biotin liposomes/avidin were retained in the peritoneal cavity with 18% of the original activity remaining after 5 days. From 1 to 4 weeks post-treatment, peritoneal (18)F-FDG standard uptake values decreased 30% in treatment group, yet increased 44% in control group. Total number of cells in ascites was significantly higher in control versus treatment group. Omental fat in control rats had numerous tumor cells compared with treated rats. Results show the potential for (186)Re-blue-biotin-liposome/avidin system in treating advanced ovarian cancer involving peritoneal carcinomatosis.

Diagnostic accuracy of integrated FDG-PET/contrast-enhanced CT in staging ovarian cancer: comparison with enhanced CT

PURPOSE

The purpose of the study is to evaluate the accuracy of integrated positron emission tomography and computed tomography (PET/CT) with (18)F-fluorodeoxyglucose (FDG) with IV contrast for preoperative staging of ovarian cancer, in comparison with enhanced CT, using surgical and histopathological findings as the reference standard.

MATERIALS AND METHODS

Forty patients with ovarian cancer underwent FDG-PET/contrast-enhanced CT scans for staging before primary debulking surgery. PET/CT and the CT component separately, were interpreted by two experienced radiologists by consensus for each investigation. Status with regard to lesion inside and outside the pelvis was determined on the basis of histopathology. The significance of differences between the two imaging modalities was determined using the McNemar test.

RESULTS

Staging revealed stage I in 18 patients (IA, n=9; IB, n=3; IC, n=6), stage II in seven (IIA, n=2; IIB, n=3; IIC, n=2), stage III in 14 (IIIA, n=1; IIIB, n=3; IIIC, n=10), and stage IV in one. The results of CT and PET/CT were concordant with the final pathological staging in 22 out of 40 (55%) and 30 out of 40 (75%) cases, respectively. The overall lesion-based sensitivity improved from 37.6% (32 out of 85) to 69.4% (59 out of 85), specificity from 97.1% (578 out of 595) to 97.5% (580 out of 595), and accuracy from 89.7% (610 out of 680) to 94.0% (639 out of 680) between CT and PET/CT. There were significant differences in sensitivity and accuracy, with p values of 5.6 x 10(-7) and 1.2 x 10(-7), respectively.

CONCLUSION

Integrated FDG-PET/contrast-enhanced CT is a more accurate imaging modality for staging ovarian cancer and useful for selecting appropriate treatment than enhanced CT.