Does the use of diagnostic PET/CT cause stage migration in patients with primary advanced ovarian cancer?

Do PET-positive supradiaphragmatic lymph nodes predict overall survival or the success of primary surgery in patients with advanced ovarian cancer?

OBJECTIVES

Compared to conventional computed tomography (CT), fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) detects higher rates of lymph node and distant metastases in patients with ovarian cancer. However, FDG-PET/CT is not routinely performed during preoperative work-up. Therefore, we investigated the prognostic value of preoperative FDG-PET/CT in advanced epithelial ovarian cancer (EOC) and its predictive value for surgical resection in patients with no residual disease. The potential significance of PET-positive supradiaphragmatic lymph nodes (SDLNs) for these parameters was evaluated.

METHODS

All patients with FIGO IIA-IVB EOC diagnosed between March 2014 and January 2021 at our certified gynaecological cancer centre, who underwent FDG PET/CT before primary surgery were retrospectively included.

RESULTS

Fifty-three consecutive patients were included in the study. Eighteen (34 %) patients had PET-positive SDLNs. We could not demonstrate a significant correlation between PET-positive SDLNs and median overall survival (OS; SDLN-positive: 58.76 months, SDLN-negative: 60.76 months; p = 0.137) or intra- or perioperative outcomes.

CONCLUSIONS

FDG PET/CT has a higher detection rate for SDLNs in patients with ovarian cancer than CT has, as described in the literature. Moreover, PET-positive SDLNs failed to predict intraoperative outcomes or overall survival.

Alteration of glucose metabolism and expression of glucose transporters in ovarian cancer

Aerobic glycolysis also known as the Warburg effect, remains a hallmark of various cancers, including ovarian cancer. Cancer cells undergo metabolic changes to sustain their tumorigenic properties and adapt to environmental conditions, such as hypoxia and nutrient starvation. Altered metabolic pathways not only facilitate ovarian cancer cells' survival and proliferation but also endow them to metastasize, develop resistance to chemotherapy, maintain cancer stem cell phenotype, and escape anti-tumor immune responses. Glucose transporters (GLUTs), which play a pivotal role as the rate-limiting step in glycolysis, are frequently overexpressed in a variety of tumors, including ovarian cancer. Multiple oncoproteins can regulate GLUT proteins, promoting tumor proliferation, migration, and metastasis, either dependent or independent of glycolysis. This review examines the alteration of GLUT proteins, particularly GLUT1, in ovarian cancer and its impact on cancer initiation, progression, and resistance to treatment. Additionally, it highlights the role of these proteins as biomarkers for diagnosis and prognosis in ovarian cancer, and delves into novel therapeutic strategies currently under development that target GLUT isoforms.

Role of Positron Emission Tomography/Computed Tomography in Epithelial Ovarian Cancer

Ovarian cancer (OC) is the most lethal gynecological malignancy with majority of cases diagnosed in advanced stages and associated with high morbidity and mortality. Positron emission tomography/computed tomography (PET/CT) has emerged as an integral part of the management of several nongynecological cancers. We used PubMed search engine using MeSH words "ovarian cancer" and "PET/CT" and reviewed the current status of PET/CT in epithelial OC. Its application related to ovarian tumor including adnexal mass evaluation, baseline staging, as a triaging tool for upfront surgery or neoadjuvant chemotherapy, for response assessment and prognostication, and for relapse detection and treatment planning has been highlighted. we highlight the current guidelines and newer upcoming PET modalities and radiotracers.

Speculation on optimal numbers of examined lymph node for early-stage epithelial ovarian cancer from the perspective of stage migration

Introduction

In early-stage epithelial ovarian cancer (EOC), how to perform lymphadenectomy to avoid stage migration and achieve reliable targeted excision has not been explored in depth. This study comprehensively considered the stage migration and survival to determine appropriate numbers of examined lymph node (ELN) for early-stage EOC and high-grade serous ovarian cancer (HGSOC).

Methods

From the Surveillance, Epidemiology, and End Results database, we obtained 10372 EOC cases with stage T1M0 and ELN ≥ 2, including 2849 HGSOC cases. Generalized linear models with multivariable adjustment were used to analyze associations between ELN numbers and lymph node stage migration, survival and positive lymph node (PLN). LOESS regression characterized dynamic trends of above associations followed by Chow test to determine structural breakpoints of ELN numbers. Survival curves were plotted using Kaplan-Meier method.

Results

More ELNs were associated with more node-positive diseases, more PLNs and better prognosis. ELN structural breakpoints were different in subgroups of early-stage EOC, which for node stage migration or PLN were more than those for improving outcomes. The meaning of ELN structural breakpoint varied with its location and the morphology of LOESS curve. To avoid stage migration, the optimal ELN for early-stage EOC was 29 and the minimal ELN for HGSOC was 24. For better survival, appropriate ELN number were 13 and 8 respectively. More ELNs explained better prognosis only at a certain range.

Discussion

Neither too many nor too few numbers of ELN were ideal for early-stage EOC and HGSOC. Excision with appropriate numbers of lymph node draining the affected ovary may be more reasonable than traditional sentinel lymph node resection and systematic lymphadenectomy.

Extra-abdominal Lymph Node Metastases as the First Presentation in Ovarian and Fallopian Tube Carcinomas

Revision of ovarian and fallopian tube cancer presentation as extra-abdominal lymph nodes to understand the diagnostic challenges and prognostic features of these situations. Literature review in PubMed and Cochrane databases using the terms "ovarian cancer," "fallopian tube cancer," "extrapelvic lymph nodes," extra-abdominal lymph nodes," "distant lymph nodes," "initial presentation," "metastases," and "unusual presentation of ovarian cancer/unusual presentation of fallopian tube cancer" isolated and in conjunction. Articles in English were analyzed regarding revision's purpose, inclusion, and exclusion criteria and 65 were included in the final document. Statistical data was obtained with Microsoft Excel software analysis. Distant manifestations of ovarian cancer may occur through the lymphatic system and, less frequently, through hematogenous spread. These forms of spread may exist with almost no symptoms related to the primary cancer location and can justify distant disease at the initial presentation. Extra-abdominal lymph node involvement poses a clinical challenge for oncologists and oncologic gynecologists because it may occur with no or mild symptoms, and even in situations where no macroscopic disease is seen in the pelvic cavity. Histology and immunohistochemistry analyses together with a high level of suspicion are paramount to help in the diagnostic workup decisions and in finding a correct diagnosis when an extra-abdominal lymph node is the first manifested sign. Given its rarity and scarcity of information dispersed in a few case reports and small case series, further investigation is needed to understand the particularities of these tumors and their prognostic relevance.

18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) predictive score for complete resection in primary cytoreductive surgery

OBJECTIVE

To assess the value of preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) scan, combined with clinical variables, in predicting complete cytoreduction in selected patients with advanced ovarian cancer.

METHODS

We carried out a multicenter, observational, retrospective study evaluating patients who underwent primary cytoreductive surgery for advanced ovarian cancer in two Spanish centers between January 2017 and January 2022. Inclusion criteria were histological confirmation of invasive epithelial ovarian carcinoma; preoperative International Federation of Gynecology and Obstetrics (FIGO) stage III or IV; upfront cytoreductive surgery; and 18F-FDG PET/CT performed 1 month prior to surgery. A modified 18F-FDG PET/CT peritoneal cancer index score was calculated for all patients. Clinical variables and preoperative 18F-FDG PET/CT findings were analyzed and a multivariate model was constructed. A predictive score based on the odds ratio of the variables was calculated to determine patient selection.

RESULTS

A total of 45 patients underwent primary cytoreductive surgery. Complete resection was achieved in 36 (80%) patients. On multivariate analysis, two clinical variables (age ≥58 years and American Society of Anesthesiology score ≥3) and two preoperative 18F-FDG PET/CT scan findings (presence of extra-abdominal lymph node involvement and modified peritoneal cancer index value of 6 or more) were associated with gross residual disease. For this multivariate model predictive of non-complete cytoreduction, the area under the curve was 0.881. A predictive value of ≥5 was the most predictive cut-off for gross residual disease. Complete resection rate was 91.7% in patients with a score of ≤4 and 33.3% in patients with a score of ≥5 points on the predictive score.

CONCLUSIONS

In selected patients, a predictive score value ≥5 may be consider as a cut-off point for triaging patients to diagnostic laparoscopy before the primary surgery or neoadjuvant chemotherapy.

Incidence, treatment, and survival trends in older versus younger women with epithelial ovarian cancer from 2005 to 2018: A nationwide Danish study

OBJECTIVE

To examine clinical trends in Denmark for younger and older epithelial ovarian cancer (EOC) patients, focusing on incidence, treatment, and survival changes.

METHODS

We included a nationwide cohort diagnosed with EOC from 2005 to 2018. We described age-standardized incidence, surgical patterns, residual disease trends, and cancer-specific survival stratified by age (<70 and ≥ 70 years), stage, and period (2005-09, 2010-13, 2014-18).

RESULTS

We included 7522 patients. The incidence decreased from 16.3 (2005) to 11.4 (2018) per 100,000 woman-years, driven by the younger cohort. While the proportion of patients with stage IIIC-IV disease undergoing primary debulking surgery (PDS) decreased, the proportion of patients having interval debulking surgery (IDS) and no debulking surgery increased significantly. In 2014-18, 36% and 24% had PDS for younger and older patients, respectively, compared to 72% and 62% in 2005-09. In both age cohorts, the proportion of patients debulked to no residual disease increased significantly among patients with stage IIIC-IV and in the total cohort. Two-year cancer-specific survival increased from 75% (2005-09) to 84% (2014-18) for younger patients and from 53% to 66% for older patients. After adjusting for potential confounders, age ≥ 70 was associated with a 1.4-fold increased risk of cancer-specific death (95% confidence interval: 1.2,1.5).

CONCLUSIONS

The proportion of patients with advanced EOC not undergoing PDS or IDS increased significantly. During the same period, patients debulked to no residual disease, and cancer-specific survival increased. However, a survival gap in favor of the younger patients remains after adjusting for potential confounders.

EANM guideline on the role of 2-[18F]FDG PET/CT in diagnosis, staging, prognostic value, therapy assessment and restaging of ovarian cancer, endorsed by the American College of Nuclear Medicine (ACNM), the Society of Nuclear Medicine and Molecular Imaging (SNMMI) and the International Atomic Energy Agency (IAEA)

In most patients with ovarian carcinoma, the diagnosis is reached when the disease is long past the initial stages, presenting already an advanced stage, and they usually have a very bad prognosis. Cytoreductive or debulking surgical procedures, platinum-based chemotherapy and targeted agents are key therapeutic elements. However, around 7 out of 10 patients present recurrent disease within 36 months from the initial diagnosis. The metastatic spread in ovarian cancer follows three pathways: contiguous dissemination across the peritoneum, dissemination through the lymphatic drainage and, although less importantly in this case, through the bloodstream. Radiological imaging, including ultrasound, CT and MRI, are the main imaging techniques in which management decisions are supported, CT being considered the best available technique for presurgical evaluation and staging purposes. Regarding 2-[¹⁸F]FDG PET/CT, the evidence available in the literature demonstrates efficacy in primary detection, disease staging and establishing the prognosis and especially for relapse detection. There is limited evidence when considering the evaluation of therapeutic response. This guideline summarizes the level of evidence and grade of recommendation for the clinical indications of 2-[¹⁸F]FDG PET/CT in each disease stage of ovarian carcinoma.

Diagnostic performance of PET/CT and PET/MR in the management of ovarian carcinoma-a literature review

Ovarian cancer is a challenging disease. It often presents at an advanced stage with frequent recurrence despite optimal management. Accurate staging and restaging are critical for improving treatment outcomes and determining the prognosis. Imaging is an indispensable component of ovarian cancer management. Hybrid imaging modalities, including positron emission tomography/computed tomography (PET/CT) and PET/magnetic resonance imaging (MRI), are emerging as potential non-invasive imaging tools for improved management of ovarian cancer. This review article discusses the role of PET/CT and PET/MRI in ovarian cancer.

Exploring variations in ovarian cancer survival by age and stage (ICBP SurvMark-2): A population-based study

OBJECTIVE

The study aims to evaluate the differences in ovarian cancer survival by age and stage at diagnosis within and across seven high-income countries.

METHODS

We analyzed data from 58,161 women diagnosed with ovarian cancer during 2010-2014, followed until 31 December 2015, from 21 population-based cancer registries in Australia, Canada, Denmark, Ireland, New Zealand, Norway, and United Kingdom. Comparisons of 1-year and 3-year age- and stage-specific net survival (NS) between countries were performed using the period analysis approach.

RESULTS

Minor variation in the stage distribution was observed between countries, with most women being diagnosed with 'distant' stage (ranging between 64% in Canada and 71% in Norway). The 3-year all-ages NS ranged from 45 to 57% with Australia (56%) and Norway (57%) demonstrating the highest survival. The proportion of women with 'distant' stage was highest for those aged 65-74 and 75-99 years and varied markedly between countries (range:72-80% and 77-87%, respectively). The oldest age group had the lowest 3-year age-specific survival (20-34%), and women aged 65-74 exhibited the widest variation across countries (3-year NS range: 40-60%). Differences in survival between countries were particularly stark for the oldest age group with 'distant' stage (3-year NS range: 12% in Ireland to 24% in Norway).

CONCLUSIONS

International variations in ovarian cancer survival by stage exist with the largest differences observed in the oldest age group with advanced disease. This finding endorses further research investigating international differences in access to and quality of treatment, and prevalence of comorbid conditions particularly in older women with advanced disease.

Ovarian cancer stage, variation in transvaginal ultrasound examination rates and the impact of an urgent referral pathway: A national ecological cohort study

INTRODUCTION

The aim of this study was to determine whether variation in transvaginal ultrasound examination rates in Danish general practice populations is associated with ovarian cancer outcomes, and to explore the impact of the introduction of a cancer patient pathway for ovarian cancer.

MATERIAL AND METHODS

We performed a national register-based cohort study of gynecological cancer-free women aged 40 years or above, living in Denmark and listed with a specific general practitioner in 2004-2014. Practice populations were divided into quartiles according to the general practitioners' transvaginal ultrasound propensity in the preceding year. Associations between transvaginal ultrasound rates and ovarian cancer outcomes were analyzed using Poisson and logistic regression.

RESULTS

We included 2769 general practices with 1 739 422 listed women, of whom 5325 were diagnosed with ovarian cancer during the study period. Practices varied twofold in transvaginal ultrasound rates before and after the implementation of the cancer patient pathway. Before the cancer patient pathway was introduced, women listed with practices with the highest transvaginal ultrasound rates were diagnosed with earlier stages of ovarian cancer (odds ratio 1.38, 95% confidence interval 1.06 to 1.81) and had a higher proportion of borderline tumors (incidence rate ratio 1.38, 95% confidence interval 1.10 to 1.75) compared with women least exposed to transvaginal ultrasound. After the cancer patient pathway, no significant differences were identified between the groups.

CONCLUSIONS

Before the cancer patient pathway, women exposed most to transvaginal ultrasound were significantly more likely to be diagnosed with early stage ovarian cancer compared with those least exposed to transvaginal ultrasound. After the cancer patient pathway was implemented, the difference disappeared. This suggests that increased awareness and access to transvaginal ultrasound is useful for diagnosing early-stage ovarian cancer.

Linked Hexokinase and Glucose-6-Phosphatase Activities Reflect Grade of Ovarian Malignancy

PURPOSE

Malignant cells exhibit increased rates of aerobic glycolysis. Here, we tested whether the accumulation of fluoro-deoxyglucose-6-phosphate (FDG6P) in ovarian cancers of differential malignancy reflects inversely correlated elevations of hexokinase (HK) and glucose-6-phosphatase (G6Pase) activities.

PROCEDURES

Twenty-nine women with suspected ovarian cancer had positron emission tomography (PET) prior to surgery. From fresh-frozen tissue, we determined the activities of HK and G6Pase, and from the PET images, we determined the tumor maximum standardized uptake value (SUVmax) of 2-deoxy-2-[¹⁸F]fluoro-D-glucose.

RESULTS

The SUVmax of malignant lesions significantly exceeded the SUVmax of benign (p < 0.005) and borderline lesions (p < 0.0005) that did not differ significantly. We found no significant correlation between measured HK or G6Pase activities and histological tumor type or SUVmax except that G6Pase activities were higher in malignant than borderline lesions (p < 0.05). Measured HK and G6Pase activities correlated inversely (p < 0.05). The slopes from the regression lines of the three correlations yielded positively correlated abscissa and ordinate intercepts, designated HK_max and G6Pase_max, respectively (r = 0.67, p < 0.0001). The positive correlations between the abscissa and ordinate intercepts with SUVmax had regression coefficients of r = 0.44, p < 0.05; and r = 0.39, p < 0.05, respectively.

CONCLUSIONS

The results distinguished two ovarian cancer phenotypes, one with elevated HK activity and low G6Pase activity, and another with the opposite characteristics.

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.

Confounders other than comorbidity explain survival differences in Danish and Swedish ovarian cancer patients - a comparative cohort study

OBJECTIVE

Danish ovarian cancer (OC) patients have previously been found to have worse prognosis than Swedish patients, and comorbidity has been suggested as a possible explanation for this survival difference. We aimed to investigate the prognostic impact of comorbidity in surgically treated OC patients in Denmark and Sweden.

METHODS

This comparative cohort study was based on data from 3118 surgically treated OC patients diagnosed in 2012-2015. The Swedish subcohort (n = 1472) was identified through the Swedish National Quality Register of Gynecological Surgery, whereas the Danish subcohort (n = 1646) originated from the Danish Gynecological Cancer Database. The clinical databases have high coverage and similar variables included. Comorbidity was classified according to the Ovarian Cancer Comorbidity Index and overall survival was the primary outcome. Data were analyzed using Kaplan Meier and Cox regression analyses. Multiple imputation was used to handle missing data.

RESULTS

We found comparable frequencies of the following comorbidities: Hypertension, diabetes and 'Any comorbidity'. Arteriosclerotic cardiac disease and chronic pulmonary disease were more common among Swedish patients. Univariable survival analysis revealed a significant better prognosis for Swedish than for Danish patients (HR 0.84 [95% CI 0.74-0.95], p < .01). In adjusted multivariable analysis, Swedish patients had nonsignificant better prognosis compared to Danish patients (HR 0.91 [95% CI 0.80-1.04], p = .16). Comorbidity was associated with survival (p = .02) but comorbidity did not explain the survival difference between the two countries.

CONCLUSIONS

Danish OC patients have a poorer prognosis than patients in Sweden but the difference in survival seems to be explained by other factors than comorbidity.

Fludeoxyglucose F 18 PET/CT Assessment of Ovarian Cancer

Ovarian cancer is one of the most common gynecologic cancers and one of the leading causes of cancer death in women. It is often asymptomatic in early stages, and thus most patients are diagnosed when it is of advanced stage. For these reasons, the role of biomarkers and tomographic imaging is crucial. Fludeoxyglucose F 18 PET/CT is a useful imaging modality in different clinical settings of the disease, overcoming some limits of conventional imaging and influencing prognosis and therapeutic approaches. PET/MR imaging is an emerging modality, and its potential role remains to be explored.

Comparison of fluorine-18 fluorodeoxyglucose positron emission tomography with gallium-67 scintigraphy in the initial clinical staging of diffuse large B-cell lymphoma

Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) has been recommended as a complementary tool for the staging of various malignancies, including malignant lymphoma. PET findings often shift patients to higher stages and may affect treatment outcomes. In this study, we retrospectively compared staging and treatment outcomes of newly diagnosed diffuse large B-cell lymphoma (DLBCL) assessed by PET (n = 153) or gallium-67 scintigraphy (Ga) (n = 95). In total, Ga upstaged two (2.1%) of 95 patients, whereas PET upstaged 13 (8.5%) of 153 patients. Bone/bone marrow (15 vs. 4%, P = 0.01) and muscle lesion (5 vs. 0%, P = 0.03) were identified more frequently in the PET group than in the Ga group. The estimated 3-year overall and progression-free survival rates did not differ significantly in the two groups at any stage. However, patients with stage III disease tended to have better progression-free survival in the PET group than in the Ga group [92.3 (95% CI 56.6-98.9%) vs. 58.3% (95% CI 27.0-80.1%), P = 0.086]. These results suggest that PET has a greater potential in detecting musculoskeletal lesions of DLBCL as extranodal lesions than Ga, and may contribute to the optimal staging.

Molecular Imaging and Precision Medicine in Uterine and Ovarian Cancers

Gynecologic cancer is a heterogeneous group of diseases both functionally and morphologically. Today, PET coupled with computed tomography (PET/CT) or PET/MR imaging play a central role in the precision medicine algorithm of patients with gynecologic malignancy. In particular, PET/CT and PET/MR imaging are molecular imaging techniques that not only are useful tools for initial staging and restaging but provide anatomofunctional insight and can serve as predictive and prognostic biomarkers of response in patients with gynecologic malignancy.

Prognostic implication of the metastatic lesion-to-ovarian cancer standardised uptake value ratio in advanced serous epithelial ovarian cancer

OBJECTIVES

To evaluate the prognostic value of metabolic activity of metastatic lesions measured by ¹⁸F-flurodeoxyglucose (¹⁸F-FDG) uptake on preoperative positron emission tomography/computed tomography (PET/CT) in patients with advanced serous epithelial ovarian cancer (EOC).

METHODS

Clinico-pathological variables and PET/CT parameters such as the maximum standardised uptake value of the ovarian cancer (SUV_ovary), metastatic lesions (SUV_meta), and the metastatic lesion-to-ovarian cancer standardised uptake value ratio (SUV_meta/SUV_ovary) were assessed in International Federation of Gynaecology and Obstetrics (FIGO) stage III, IV patients.

RESULTS

Clinico-pathological data were retrospectively reviewed for 94 eligible patients. The median progression-free survival (PFS) was 18.5 months (range, 6-90 months), and 57 (60.6%) patients experienced recurrence. Older age [P = 0.017, hazard ratio (HR) 1.036, 95% CI 1.006-1.066], residual disease after surgery (P = 0.024, HR 1.907, 95% CI 1.087-3.346), and high SUV_meta/SUV_ovary (P = 0.019, HR 2.321, 95% CI 1.148-4.692) were independent risk factors of recurrence. Patients with high SUV_meta/SUV_ovary showed a significantly worse PFS than those with low SUV_meta/SUV_ovary (P = 0.007, log-rank test).

CONCLUSIONS

Preoperative SUV_meta/SUV_ovary was significantly associated with recurrence and has an incremental prognostic value for PFS in patients with advanced serous EOC.

KEY POINTS

• The prognostic value of the metabolic activity of metastatic lesions was investigated. • SUV_meta/SUV_ovary was significantly associated with recurrence of serous EOC. • Preoperative SUV_meta/SUV_ovary can be a predicator of serous EOC recurrence.

F-18 FDG PET/CT metabolic tumor volume predicts overall survival in patients with disseminated epithelial ovarian cancer

OBJECTIVE

We evaluated the prognostic impact of quantitative assessment by maximum standardized uptake value (SUVmax), metabolic tumour volume (MTV) and tumour lesion glycolysis (TLG) on [F-18] FDG PET/CT for patients with peritoneal carcinomatosis from epithelial ovarian cancer (EOC).

METHODS

Thirty-one patients with EOC underwent PET/CT for an early restaging after cytoreductive surgery, having been diagnosed with carcinomatosis (before chemotherapy). The SUVmax, MTV (cm³; 42% threshold) and TLG (g) were registered on residual peritoneal lesions. The patients were followed up 20±12months thereafter. The PET/CT results were compared to overall survival (OS).

RESULTS

The Kaplan-Meier survival analysis for the SUVmax did not reveal significant differences in OS (p=0.48). The MTV survival analysis showed a significant higher OS in patients presenting with a higher tumour burden than those with less tumour burden (p=0.01; 26 vs. 14 months), whereas TLG exhibited a similar trend though not significant (p=0.06). Apart from chemo-resistance, the higher the MTV, the better will be the response to chemotherapy.

CONCLUSIONS

Quantitative assessment by MTV rather than by SUVmax and TLG on PET/CT may be helpful for stratifying patients who present with peritoneal carcinomatosis from EOC, in order to implement the appropriate therapeutic regimen.

Diagnostic role of 18F-FDG PET/MRI in patients with gynecological malignancies of the pelvis: A systematic review and meta-analysis

PURPOSE

The aim of this study was to assess the diagnostic performance of 18F-FDG Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) for gynecological cancers of the pelvis, based on a systematic review and meta-analysis of published data.

METHODS

We performed a comprehensive literature search of Pubmed and Embase for studies that evaluated the diagnosis of 18F-FDG PET/MRI for gynecological malignancies in the pelvis. Quality Assessment for Studies of Diagnostic Accuracy 2 (QUADAS 2) tool was used to access the quality of included studies. After testing heterogeneity of the pooled studies with I^2 and H^2 (calculated using metaan in Stata12.0) we treated the data that extracted and transformation from the studies, based on DerSimonian-Laird method(Random-effects models),then back-transformation them to percentages and plotting to get the pooled sensitivity, specificity, likelihood ratios, and constructed summary receiver operating characteristics (SROC) curve.

RESULTS

Eventually, 7 studies fulfilled our predefined inclusion criteria were included in our research. On patient-based assessment, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio of 18F-FDG PET/MRI for diagnosis of gynecological malignancies were 0.95 (95%CI 0.86-0.99), 0.95 (95% CI 0.74-1.00), 7.51 (95% CI 2.29-24.59), 0.12 (95% CI 0.05-0.29) and 116.27 (95% CI 17.07-791.74), respectively. On lesion-based assessment, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and the summary DOR were 0.89 (95%CI 0.84-0.93), 0.87 (95%CI 0.74-0.95), 6.99 (95%CI 3.30-14.79), 0.12 (95%CI 0.06-0.25) and 55.82 (95%CI 20.91-149.05), respectively.

CONCLUSIONS

Our meta-analysis indicated that 18F-FDG PET/MRI, combined the advantages of MRI and PET, may be a very promising diagnostic method to assess the primary tumor and nodal staging in patients with gynecological malignancies of the pelvis.

Systematic Review on the Accuracy of Positron Emission Tomography/Computed Tomography and Positron Emission Tomography/Magnetic Resonance Imaging in the Management of Ovarian Cancer: Is Functional Information Really Needed?

Ovarian cancer (OC) often presents at an advanced stage with frequent relapses despite optimal treatment; thus, accurate staging and restaging are required for improving treatment outcomes and prognostication. Conventionally, staging of OC is performed using contrast-enhanced computed tomography (CT). Nevertheless, recent advances in the field of hybrid imaging have made positron emission tomography/CT (PET/CT) and PET/magnetic resonance imaging (PET/MRI) as emerging potential noninvasive imaging tools for improved management of OC. Several studies have championed the role of PET/CT for the detection of recurrence and prognostication of OC. We provide a systematic review and meta-analysis of the latest publications regarding the role of molecular imaging in the management of OC. We retrieved 57 original research articles with one article having overlap in both diagnosis and staging; 10 articles (734 patients) regarding the role of PET/CT in diagnosis of OC; 12 articles (604 patients) regarding staging of OC; 22 studies (1429 patients) for detection of recurrence; and 13 articles for prognostication and assessment of treatment response. We calculated pooled sensitivity and specificity of PET/CT performance in various aspects of imaging of OC. We also discussed the emerging role of PET/MRI in the management of OC. We aim to give the readers and objective overview on the role of molecular imaging in the management of OC.

Surgery for advanced epithelial ovarian cancer

Cytoreductive surgery for patients with advanced epithelial ovarian cancer has been practised since the pioneering work of Tom Griffiths in 1975. Further research has demonstrated the prognostic significance of the extent of metastatic disease pre-operatively, and of complete cytoreduction post-operatively. Patients with advanced epithelial ovarian cancer should be referred to high volume cancer units, and managed by multidisciplinary teams. The role of thoracoscopy and resection of intrathoracic disease is presently investigational. In recent years, there has been increasing use of neoadjuvant chemotherapy and interval cytoreductive surgery in patients with poor performance status, which is usually due to large volume ascites and/or large pleural effusions. Neoadjuvant chemotherapy reduces the post-operative morbidity, but if the tumour responds well to the chemotherapy, the inflammatory response makes the surgery more difficult. Post-operative morbidity is generally tolerable, but increases in older patients, and in those having multiple, aggressive surgical procedures, such as bowel resection or diaphragmatic stripping. Primary cytoreductive surgery should be regarded as the gold standard for most patients until a test is developed which would allow the prediction of platinum resistance pre-operatively.

FIGO stage IV epithelial ovarian, fallopian tube and peritoneal cancer revisited

Epithelial ovarian, fallopian tube and peritoneal cancer (EOC) is the seventh most common cancer diagnosis among women worldwide and shows the highest mortality rate of all gynecologic tumors. Different histological and anatomic spread patterns as well as multiple gene-expression based studies have demonstrated that EOC is indeed a heterogeneous disease. The prognostic factors that best predict the survival in this disease include: age, performance status and patient's comorbidities at the time of diagnosis; tumor biology, histological type, amount of residual tumor after surgery and finally tumor stage as surrogate for pre-operative tumor burden and growth pattern. In the majority of patients, the disease is diagnosed in advanced stage, disseminated intra- and/or extra-abdominally. It is unclear whether this is a consequence of distinct tumor biology, absence of anatomic barriers between ovary and the abdominal cavity, delay of diagnosis and/or the lack of sufficient early detection methods. FIGO stage IV disease, defined as tumor spread outside the abdominal cavity (including malignant pleural effusion) and/or visceral metastases, will be present in 12-33% of the patients at initial diagnosis. Overall, median survival for patients with stage IV disease ranges from 15 to 29months, with an estimated 5-year survival of approximately 20%. Unfortunately, over the past decades the overall survival gain compared to stage III remains disappointing. The current review aims to summarize the current data published in the international literature concerning FIGO stage IV EOC and discusses the published evidence for the clinical management of these patients.

Survival of ovarian cancer patients in Denmark: Results from the Danish gynaecological cancer group (DGCG) database, 1995-2012

BACKGROUND

Ovarian cancer has a high mortality rate, especially in Denmark where mortality rates have been reported higher than in adjacent countries with similar demographics. This study therefore examined recent survival and mortality among Danish ovarian cancer patients over an 18-year study period.

METHODS

This nationwide registry-based observational study used data from the Danish Gynecology Cancer Database, Danish Pathology Registry, and Danish National Patient Registry. All patients with ovarian cancer diagnosed between 1995 and 2012 were included in the study. The data sources were linked via the patients' personal identification number and the analyses included data on cancer stage, age, survival, surgery status and comorbidity. The computed outcome measures were age-adjusted mortality rates and age-adjusted overall and relative survival rates for one and five years.

RESULTS

We identified 9972 patients diagnosed with ovarian cancer in the period 1995-2012. The absolute one-year mortality rate decreased from 42.8 (CI 40.3-45.6) in 1995-1999 to 28.3 (CI 25.9-30.9) in 2010-2012, and the five-year mortality rate decreased from 28.2 (CI 27.0-29.5) in 1995-1999 to 23.9 (CI 22.9-25.0) in 2005-2009. After stratification by age, comorbidity and cancer stage, the decrease in one-year mortality was most substantial in the 65-74 year old age group 41.1 (CI 38.8-43.5) to 26.5 (CI 24.4-28.7) and for stage III 39.1 (CI 35.1-43.6) to 22.9 (CI 19.9-26.5) and stage IV 91.3 (CI 80.8-103.2) to 41.9 (CI 35.5-49.5). For overall survival, we showed an increase in one-year survival from 68% (CI 66-69%) in 1995-1999 to 76% (CI 74-78%) in 2010-2012 and an increase in five-year survival from 33% (CI 32-35%) in 1995-1999 to 36% (CI 34-38%) in 2005-2009. Relative survival showed similar increases through the period.

CONCLUSIONS

Ovarian cancer survival in Denmark has improved substantially from 1995 to 2012, bringing Denmark closer to the standards set by adjacent countries.

Nuclear medicine for imaging of epithelial ovarian cancer

Cancer is one of the leading causes of mortality worldwide. Usually, the diagnosis of cancer at an early stage is important to facilitate proper treatment and survival. Nuclear medicine has been successfully used in the diagnosis, staging, therapy and monitoring of cancers. Single-photon emission computed tomography and PET-based companion imaging agents are in development for use as a companion diagnostic tool for patients with ovarian cancer. The present review discusses the basic and clinical studies related to the use of radiopharmaceuticals in the diagnosis and management of ovarian cancer, focusing on their utility and comparing them with other imaging techniques such as computed tomography and MRI.

Predictive value of (18)F-FDG PET/CT in restaging patients affected by ovarian carcinoma: a multicentre study

PURPOSE

Ovarian cancer is the eighth most common malignancy among women and has a high mortality rate. Prognostic factors able to drive an effective therapy are essential. (18)F-Fluoro-2-deoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) has been investigated in patients with epithelial ovarian cancer and showed promise in diagnosing, staging, detecting recurrent lesions and monitoring treatment response. Conversely, its prognostic role remains unclear. We aimed at assessing the prognostic value of (18)F-FDG PET/CT performed in the restaging process in a multicentre study.

METHODS

We evaluated 168 patients affected by ovarian carcinoma, who underwent a restaging (18)F-FDG PET/CT. The presence of local recurrences, lymph node involvement and distant metastasis was recorded as well as lesion dimensions, maximum and mean standardized uptake values (SUVmax and SUVmean, respectively). Progression-free survival (PFS) and overall survival (OS) at 3 and 4 years were computed by using Kaplan-Meier curves. Increased odds ratio was assessed using Cox regression analysis testing all lesion parameters measured by PET/CT.

RESULTS

PFS was significantly longer in patients with a negative than a positive restaging PET/CT study (3- and 4-year PFS 64 and 53% vs 23 and 12%, respectively; p < 0.001). Similarly, a negative study was associated with a significantly higher OS rate after 4 years of follow-up (67 vs 25% in negative and positive groups, respectively; p < 0.001). Lymph node or distant involvement were also independently associated with an increased risk of disease progression [hazard ratio (HR) 1.6 and 2.2, respectively; p = 0.003]. Moreover, PET/CT showed an incremental prognostic value compared to the International Federation of Gynecology and Obstetrics (FIGO) staging system. In the analysis of patient subsets, individuals with the same FIGO stage I-II but with negative PET had a significantly better 4-year OS than patients with low FIGO stage but positive PET. This implies that patients with the same FIGO stage can be further prognostically stratified using PET (p = 0.01). At receiver-operating characteristic (ROC) analysis, no thresholds for semiquantitative parameters were predictive of a worse outcome.

CONCLUSION

(18)F-FDG PET/CT has an important prognostic value in assessing the risk of disease progression and mortality rate. An efficacious therapy planning might therefore effectively rely on (18)F-FDG PET/CT findings. Semiquantitative data were not proven to be an effective tool to predict disease progression.

PET/MRI and PET/CT in advanced gynaecological tumours: initial experience and comparison

PURPOSE

To compare the diagnostic accuracy of PET/MRI and PET/CT for staging and re-staging advanced gynaecological cancer patients as well as identify the potential benefits of each method in such a population.

MATERIAL AND METHODS

Twenty-six patients with suspicious or proven advanced gynaecological cancer (12 ovarian, seven cervical, one vulvar and four endometrial tumours, one uterine metastasis, and one primary peritoneal cancer) underwent whole-body imaging with a sequential trimodality PET/CT/MR system. Images were analysed regarding primary tumour detection and delineation, loco-regional lymph node staging, and abdominal/extra-abdominal distant metastasis detection (last only by PET/CT).

RESULTS

Eighteen (69.2 %) patients underwent PET/MRI for primary staging and eight patients (30.8 %) for re-staging their gynaecological malignancies. For primary tumour delineation, PET/MRI accuracy was statistically superior to PET/CT (p < 0.001). Among the different types of cancer, PET/MRI presented better tumour delineation mainly for cervical (6/7) and endometrial (2/3) cancers. PET/MRI for local evaluation as well as PET/CT for extra-abdominal metastases had therapeutic consequences in three and one patients, respectively. PET/CT detected 12 extra-abdominal distant metastases in 26 patients.

CONCLUSION

PET/MRI is superior to PET/CT for primary tumour delineation. No differences were found in detection of regional lymph node involvement and abdominal metastases detection.

KEY POINTS

• PET/MRI is superior to PET/CT for primary tumour delineation • PET/CT represents a reliable tool to detect extra-abdominal distant metastasis • PET/MRI might be the preferred imaging modality for staging cervical and endometrial tumours • Whole-body staging for detection and evaluation of extra-abdominal metastases is mandatory.

The impact of pleural disease on the management of advanced ovarian cancer

Malignant pleural effusion is the most common site of stage IV ovarian cancer. A positive cytology is required for a stage IVA diagnosis. Unfortunately, the accuracy rate of pleural cytology remains low. A number of factors have been identified as prognostic for clinical outcomes in patients with epithelial ovarian cancer (EOC), the International Federation of Gynaecology and Obstetrics (FIGO) stage and residual tumor after debulking surgery being the most widely reported. Thereby careful selection of patients is crucially important, yet no preoperative predictor has proven sufficiently reliable to predict surgical outcome. The authors present a review of the literature on stage IV ovarian cancer specifically focusing on prognostic value of FIGO stage, preoperative workup, role of video-assisted thoracic surgery and maximal cytoreductive surgery.

The role of metabolic tumor volume and total lesion glycolysis on ¹⁸F-FDG PET/CT in the prognosis of epithelial ovarian cancer

PURPOSE

This study assessed the prognostic value of pre-operative 2-[(18)F] fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) volumetric parameters, including metabolic tumor volume (MTV) and total lesion glycolysis (TLG), in patients with epithelial ovarian cancer.

METHODS

A total of 175 patients with epithelial ovarian cancer who underwent (18) F-FDG PET/CT and subsequent cytoreductive surgery were retrospectively enrolled. Maximum standardized uptake value (SUVmax) on (18)F-FDG PET/CT was measured for all patients. Because nine patients showed low tumor-to-background uptake ratios, MTV and TLG were measured in 166 patients. Univariate and multivariate analyses were performed to evaluate the prognostic significance of SUVmax, MTV, TLG, and clinicopathological factors for disease progression-free survival.

RESULTS

Disease progressed in 78 (44.6 %) of the 175 patients, and the 2-year disease progression-free survival rate was 57.5 %. Univariate analysis showed that tumor stage, histopathological type, presence of regional lymph node metastasis, residual tumor after cytoreductive surgery, pre-operative serum carbohydrate antigen 125 (CA125) level, SUVmax, MTV, and TLG were significant prognostic factors (p < 0.05). Among these variables, tumor stage (p = 0.0006) and TLG (p = 0.008) independently correlated with disease progression-free survival on multivariate analysis. The disease progression rate was only 2.3 % in stage I-II patients with low TLG (≤100.0), compared to 80.0 % in stage III-IV patients with high TLG (>100.0).

CONCLUSION

Along with tumor stage, TLG is an independent prognostic factor for disease progression after cytoreductive surgery in patients with epithelial ovarian cancer. By combining tumor stage and TLG, one can further stratify the risk of disease progression for patients undergoing cytoreductive surgery.

Perimenopausal ovarian carcinoma patient with subclavian node metastasis proven by immunohistochemistry

Ovarian cancer is the seventh most common cancer in the world and the fifth most common cause of death from cancer; it is responsible for over half of all deaths related to gynecological cancers. The presence of lymphatic metastasis is an important prognostic factor in ovarian cancer. Nodal metastases to the pelvic and the para-aortic lymph nodes are common, particularly in an advanced of the disease (stages III-IV). The finding of distant nodal metastasis, especially subclavian lymph node metastasis, from ovarian carcinoma is very uncommon. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) or FDG-PET/computed tomography (CT) provides an improved imaging for detecting metastatic lymph nodes in patients with ovarian cancer. Immunohistochemically, ovarian carcinoma cells are positive for estrogen receptor, progesterone receptor, cancer antigen 125, Wilms' tumor 1 protein, and p53; they are negative for thyroid transcription factor (TTF-1) and caudal-related homeobox 2 (CDX-2). This report describes a Korean woman diagnosed with ovarian cancer with subclavian lymph node metastasis revealed by FDG PET/CT and verified by an immunohistochemical staining. Differentiating between the primary ovarian lesion and the metastatic lesion will allow the initiation of an appropriate treatment and help predict the prognosis.

Preoperative 18F-FDG PET/CT in the management of advanced epithelial ovarian cancer

OBJECTIVE

The introduction of 18-FDG-PET/CT during preoperative evaluation of patients with epithelial ovarian cancer (EOC) has led to an increase of the detection of extra-abdominal metastases. However, the clinical impact of this upstage remains unclear.

METHODS

Patients with suspected advanced EOC underwent 18-FDG-PET/CT within two weeks prior to debulking surgery.

RESULTS

Between 2006 and 2011 95 patients met the inclusion criteria. Based on the concordance or the discrepancy of clinical and PET/CT stage, patients were divided into 3 groups (A: clinical and PET III; B: clinical III and PET IV; C: clinical and PET IV). Twenty-five patients were upstaged from FIGO stage III to stage IV by PET/CT. The proportion of patients who achieved a residual tumor <1cm in group B and C was similar, whereas it was significantly lower compared to group A. Similarly, complete response to adjuvant chemotherapy was achieved more frequently in patients in group A. PFS was similar in the three groups (17, 17 and 12 months in group A, B and C), as well as OS (51, 41 and 35 months).

CONCLUSIONS

PET/CT is able to detect distant metastases in EOC patients. The presence of extra-abdominal disease probably indicates a more aggressive disease which also shows a lower response to standard chemotherapy. However, upstaged patients have a similar prognosis compared to stage III patients, probably because intra-abdominal disease is more likely to lead patients to death. This might also explain why residual tumor is the most important prognostic factor for advanced EOC patients.

A prospective comparison of integrated FDG-PET/contrast-enhanced CT and contrast-enhanced CT for pretreatment imaging of advanced epithelial ovarian cancer

OBJECTIVE

The use of tumor debulking surgery in the management of epithelial ovarian cancer (EOC), which is often disseminated in the peritoneal cavity at the time of diagnosis, has a significant impact on prognosis. We compared (18)F-fluorodeoxyglucose (FDG) positron emission tomography/contrast-enhanced computed tomography (PET/CT) to contrast-enhanced CT for the detection of dissemination into the abdominal cavity preventing successful primary debulking surgery.

METHODS

Forty-one women with EOC underwent preoperative whole-body low-dose FDG-PET/CT followed by diagnostic high dose contrast-enhanced CT scan, and the results were compared with systematically recorded surgical findings as a reference standard. Both site-based and patient-based analyses were conducted.

RESULTS

FDG-PET/CT was superior to conventional CT for the detection of carcinomatosis in subdiaphragmatic peritoneal surfaces (p=0.020) and in the bowel mesentery (p=0.001). Patient-based analysis of upper abdominal areas requiring extensive surgical procedures showed no significant differences between the two imaging methods. The sensitivity of PET/CT and CT was poor in certain areas of the peritoneal cavity (64% vs. 27% in the small bowel mesentery and 65% vs. 55% in the right upper abdomen). Extra-abdominal disease spread was detected by PET/CT in 32 patients and by CT in 25 patients.

CONCLUSIONS

PET/CT was not superior to CT for the detection of intra-abdominal disease spread. Patients with suspected EOC should be referred for upfront radical surgery regardless of the results of preoperative imaging studies. PET/CT is more effective for the detection of extra-abdominal disease than CT, but the clinical significance of this finding is unclear.

Prognostic value of preoperative metabolic tumor volume and total lesion glycolysis in patients with epithelial ovarian cancer

PURPOSE

Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are measures of metabolic activity of tumors determined by fluorine-18 fluorodeoxyglucose ([(18)F]FDG) uptake on PET/CT images. The purpose of this study was to investigate the relationship between functional tumor parameters (MTV and TLG) and clinical outcomes in patients with epithelial ovarian cancer (EOC).

METHODS

Fifty-five patients with EOC who had undergone [(18)F]FDG PET/CT before surgical staging were included in this retrospectively study. For each patient, we determined the highest (SUV(max) and SUV(avg)), the cumulative TLG, and the sum of all MTV, and compared their predictive value of recurrence and the effects of pretreatment functional tumor activity on progression-free interval (PFI).

RESULTS

The median duration of PFI was 11 (range 3-43) months, and 20 patients (36.4%) experienced recurrence. Poor outcome was associated with higher values for both the MTV (P = 0.022, hazard ratio 5.571, 95% confidence interval 1.279-24.272) and the TLG (P = 0.037, hazard ratio 2.967, 95% confidence interval 1.065-8.265). The Kaplan-Meier survival graphs showed a significant difference in PFI between the groups categorized by MTV and TLG, respectively (P = 0.01 for MTV, P = 0.0287 for TLG, log rank test).

CONCLUSIONS

Pretreatment metabolic parameters such as MTV and TLG showed statistically significant association with recurrence in patients with EOC. These values can be useful quantitative criteria for disease prognostication in patients with EOC before treatment.

Prognostic significance of mediastinal 18F-FDG uptake in PET/CT in advanced ovarian cancer

PURPOSE

To evaluate the prognostic significance of increased mediastinal (18)F-FDG uptake in PET/CT for the staging of advanced ovarian cancer.

METHODS

We retrospectively evaluated patients managed for FIGO stage III/IV ovarian cancer between 1 January 2006 and 1 June 2009. Patients were included if they had undergone (18)F-FDG PET/CT and surgery for initial staging. Exclusion criteria were age younger than 18 years, inability to undergo general anaesthesia, recurrent ovarian cancer, and borderline or nonepithelial malignancy. Whole-body PET/CT was performed after intravenous (18)F-FDG injection. The location of abnormal hot spots and (18)F-FDG maximal standard uptake values (SUV(max)) were recorded. We compared the complete cytoreduction and survival rates in groups defined based on mediastinal (18)F-FDG uptake and SUV(max) values. Kaplan-Meier curves of overall survival and disease-free survival were compared using the log-rank test. Hazard ratios with their 95% confidence intervals were computed. Adjusted hazard ratios were obtained using a multivariate Cox model.

RESULTS

We included 53 patients, of whom 17 (32%) had increased mediastinal (18)F-FDG uptake. Complete cytoreduction was achieved in 14 (87.5%) of the 16 patients managed with primary surgery and in 21 (75%) of the 28 patients managed with interval surgery. Complete cytoreduction was achieved significantly more often among patients without increased mediastinal (18)F-FDG uptake (80.6% vs. 35.3%; p = 0.001). Disease-free survival was comparable between the two groups. By univariate analysis, overall mortality was significantly higher among patients with increased mediastinal (18)F-FDG uptake (hazard ratio 5.70, 95% confidence interval 1.74-18.6). The only factor significantly associated with overall survival by multivariate analysis was complete cytoreduction (adjusted hazard ratio 0.24, 95% confidence interval 0.07-0.89).

CONCLUSION

Increased mediastinal (18)F-FDG uptake was common in patients with advanced ovarian cancer. However, complete cytoreduction, which was significantly more frequent among patients without mediastinal (18)F-FDG uptake, was the only factor independently associated with survival.

PET/CT in gynecologic cancer: present applications and future prospects--a clinician's perspective

This article briefly reviews the epidemiology, diagnosis, and treatment of the common gynecologic malignancies, with an emphasis on the shortcomings of current clinical practice. The persistent need to achieve early diagnosis, adjust proper treatment, enhance surveillance, and improve the outcome of these patients has led to the development of new diagnostic modalities. Novel tools such as 18F-fluorodeoxyglucose PET/CT should aim at enhancing the clinician's ability to make critical decisions in treating difficult scenarios.

Present and future of FDG-PET/CT in ovarian cancer

Integrated FDG-PET/CT has been used successfully for the diagnosis, staging, restaging, therapy monitoring and prognostic prediction of ovarian cancer as well as various other malignant tumors. Compared with conventional PET/non-contrast CT images, combined PET/contrast-enhanced CT images with intravenous iodine contrast medium and sufficient radiation dose may contribute to a more accurate diagnosis with higher confidence. In the future, tracers other than FDG and integrated PET/MRI will be realized. We herein review the place and role of FDG-PET/CT in the management of ovarian cancer, discussing its usefulness and limitations in the imaging of these patients.

The Roles of Fluorodeoxyglucose-PET/Computed Tomography in Ovarian Cancer: Diagnosis, Assessing Response, and Detecting Recurrence

The potential roles of fluorodeoxyglucose positron emission tomography/computed tomography imaging in ovarian cancer include noninvasive characterization of an ovarian mass, staging, and treatment planning. This article assesses these roles for predicting and monitoring response to treatment, restaging, and early diagnosis of recurrence.

PET/CT in Gynecologic Cancer: Present Applications and Future Prospects-A Clinician's Perspective

This article briefly reviews the epidemiology, diagnosis, and treatment of the common gynecologic malignancies, with an emphasis on the shortcomings of current clinical practice. The persistent need to achieve early diagnosis, adjust proper treatment, enhance surveillance, and improve the outcome of these patients has led to the development of new diagnostic modalities. Novel tools such as 18F-fluorodeoxyglucose PET/CT should aim at enhancing the clinician's ability to make critical decisions in treating difficult scenarios.