Integrated PET/CT as a first-line re-staging modality in patients with suspected recurrence of ovarian cancer

Imaging of Peritoneal Metastases in Ovarian Cancer Using MDCT, MRI, and FDG PET/CT: A Systematic Review and Meta-Analysis

This review aims to compare the diagnostic performance of multidetector CT (MDCT), MRI, including diffusion-weighted imaging, and FDG PET/CT in the detection of peritoneal metastases (PMs) in ovarian cancer (OC). A comprehensive search was performed for articles published from 2000 to February 2023. The inclusion criteria were the following: diagnosis/suspicion of PMs in patients with ovarian/fallopian/primary peritoneal cancer; initial staging or suspicion of recurrence; MDCT, MRI and/or FDG PET/CT performed for the detection of PMs; population of at least 10 patients; surgical results, histopathologic analysis, and/or radiologic follow-up, used as reference standard; and per-patient and per-region data and data for calculating sensitivity and specificity reported. In total, 33 studies were assessed, including 487 women with OC and PMs. On a per-patient basis, MRI (p = 0.03) and FDG PET/CT (p < 0.01) had higher sensitivity compared to MDCT. MRI and PET/CT had comparable sensitivities (p = 0.84). On a per-lesion analysis, no differences in sensitivity estimates were noted between MDCT and MRI (p = 0.25), MDCT and FDG PET/CT (p = 0.68), and MRI and FDG PET/CT (p = 0.35). Based on our results, FDG PET/CT and MRI are the preferred imaging modalities for the detection of PMs in OC. However, the value of FDG PET/CT and MRI compared to MDCT needs to be determined. Future research to address the limitations of the existing studies and the need for standardization and to explore the cost-effectiveness of the three imaging modalities is required.

PET/Computed Tomography Transformation of Oncology: Ovarian Cancers

Over the last quarter of a century, fluorine-18-fluorodeoxyglucose (FDG) PET/computed tomography (CT) has revolutionized the diagnostic algorithm of ovarian cancer, impacting on the initial disease evaluation including staging and surgical planning, treatment response assessment and prognostication, to the most important role in detection of recurrent disease. The role of FDG PET/CT is expanding with the adoption of new therapeutic agents. Other non-FDG tracers have been explored with fibroblast activation protein inhibitor being promising. Novel tracers may provide the basis for future theragnostic work. This article will review the evolution and impact of PET/CT in ovarian cancer management.

Impact of 18 F-FDG PET on the Management in Patients With Recurrent Gynecologic cancer : A Meta-analysis

PURPOSE

Gynecological cancer is the most prevalent cancer among women worldwide. We performed a meta-analysis to assess the impact of 18 F-FDG PET on the management of patients with recurrent gynecological cancers, including cervical, uterine, and ovarian cancers.

METHODS

We systematically searched MEDLINE and EMBASE databases for English-language publications. All published studies on the impact of PET scans on the management of patients with recurrent gynecological cancers were reviewed. The proportion of management change (%), defined as the percentage of patients whose management changed after FDG PET to those who underwent FDG PET, was calculated. The data from each study were analyzed using MedCalc Statistical Software version 14.12.0 (MedCalc Software, Ostend, Belgium).

RESULTS

Nineteen studies including 6191 patients were eligible for inclusion. The impact of FDG PET scan for detecting recurrence/metastasis in patients with gynecologic cancer was evaluated using management change rates, ranging from 9.4% to 60.7% with a pooled effect of 42.0% (95% confidence interval [CI], 34.5%-49.6%; I2 = 92.9%). In the subtype analysis, FDG PET scanning resulted in changes in the management in 48.5% (95% CI, 37.8%-59.3%; I2 = 67.8%) of cervical cancer, 34.7% (95% CI, 33.4%-36.0%; I2 = 0%) of uterine cancer, and 40.3% (95% CI, 26.7%-54.7%; I2 = 95.2%) of ovarian cancer cases.

CONCLUSIONS

FDG PET has a significant impact on the restaging of patients with gynecological cancer. These findings suggest that FDG PET should be performed, especially in cases of suspected recurrence/metastasis in the main gynecologic cancer types, including cervical, ovarian, and uterine cancers.

Evaluation of follow-up strategies for women with epithelial ovarian cancer following completion of primary treatment

BACKGROUND

This is an update of a previous Cochrane Review, last updated in 2014. Ovarian cancer is the eighth most common cancer and seventh most common cause of death due to cancer in women worldwide. Traditionally, most women who have been treated for cancer undergo long-term follow-up in secondary care. However, it has been suggested that the use of routine review may not be effective in improving survival, or health-related quality of life (HRQOL), or relieving anxiety. In addition, traditional follow-up may not be cost-effective.

OBJECTIVES

To compare the potential effects of different strategies of follow-up in women with epithelial ovarian cancer, following completion of primary treatment.

SEARCH METHODS

For this update, we searched the Cochrane Gynaecological Cancer Group Trials Register, CENTRAL 2022, Issue 11, MEDLINE, and Embase from August 2013 to November 2022. We also searched review articles and contacted experts in the field.

SELECTION CRITERIA

All randomised controlled trials (RCTs) that evaluated follow-up strategies for women with epithelial ovarian cancer following completion of primary treatment.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology. Two review authors independently selected potentially relevant trials, extracted data, and assessed risk of bias. They compared results, and resolved disagreements by discussion. We assessed the certainty of evidence, using the GRADE approach, for the outcomes of interest: overall survival (OS), health-related quality of life (HRQOL), psychological effects, and cost analysis.

MAIN RESULTS

For this update, we included one new RCT, including 112 women with ovarian, fallopian tube, or peritoneal cancer, who had completed primary treatment by surgery, with or without chemotherapy. This study reported the effect of individualised, i.e. individually tailored, nurse-led follow-up versus conventional medical follow-up on HRQOL, psychological outcomes, and cost-analysis. Individualised follow-up improved HRQOL in one of the two scales, with a decrease in mean difference (MD) in the QLQ-C30 discomfort scale following 12 months of individualised treatment compared to 12 months of conventional treatment (MD -5.76 points, 95% confidence interval (CI) -10.92 to -0.60; 1 study, 112 participants; low-certainty evidence; minimal important difference 4 to 10 points). There may be little or no difference in the other HRQOL scale (QLQ-Ov28, MD -0.97 points, 95% CI -2.57 to 0.63; 1 study, 112 participants: low-certainty evidence); psychological outcome, measured with the hospital anxiety and depression scale (HADS; MD 0.10 point, 95% CI -0.81 to 1.02; 1 study, 112 participants: low-certainty evidence), or cost analysis (MD -GBP 695.00, 95% CI -1467.23 to 77.23; 1 study, 112 participants: moderate-certainty evidence). Our previous review included one RCT, with 529 women in a confirmed remission, with normal CA125 concentration and no radiological evidence of disease, after surgery and first-line chemotherapy for ovarian cancer. This study evaluated immediate treatment of ovarian cancer relapse following a rise of serum CA125 levels versus delaying treatment until symptoms developed for OS, and HRQOL. There was little or no difference in OS between the immediate and delayed arms after a median follow-up of 56.9 months (unadjusted hazard ratio (HR) 0.98, 95% CI 0.80 to 1.20; 1 study, 529 participants; moderate-certainty evidence). Time from randomisation to first deterioration in global health score or death was shorter in the immediate treatment group than in the delayed treatment group (HR 0.71, 95% CI 0.58 to 0.88).

AUTHORS' CONCLUSIONS

Limited evidence from one trial suggests that routine surveillance with CA125 in asymptomatic women and treatment at CA125-defined relapse does not seem to offer survival advantage when compared to treatment at symptomatic relapse. However, this study pre-dates the use of PARPi maintenance treatment and the increased use of secondary cytoreductive surgery, so the results may be limited in their applicability to current practice. Limited evidence from one trial suggests that individualised nurse-led follow-up may improve HRQOL in women with ovarian cancer following completion of primary treatment. Large RCTs are needed to compare different types of follow-up, looking at survival, HRQOL, psychological effects, and cost as outcomes.

Role of 18F FDG PET/CT in evaluation of post-operative ovarian carcinoma

Background

We evaluated the sensitivity, specificity and accuracy of fluorine-18-fluorodeoxyglucose with positron emission tomography/computed tomography (18F-FDG-PET/CT) in a group of patients with suspicion of ovarian cancer recurrence. It is considered a diagnostic dilemma, particularly in the 2 years following first-line therapy. CA125 serum levels computed tomography (CT) and other modalities are used during routine follow-up. These traditional modalities could provide a significant number of false-negative or equivocal results even in the presence of elevated CA125 levels. So the performance of 18F-FDG-PET/CT is essential for the optimal diagnosis of recurrence and treatment planning.

Results

Studying PET/CT behaviour in the detection of ovarian cancer recurrence, 18F-FDG-PET/CT had an accuracy of 98% with sensitivity and specificity of 98% and 100%, respectively. 18F-FDG-PET/CT had a PPV of 100% and NPV of 83%. While studying the CA125 level (> 35 U/ml) to detect the ovarian cancer recurrence during patient follow-up, the CA125 level had an accuracy of 50% with a sensitivity ratio and specificity ratio of 47% and 80%, respectively. CA-125 level had a PPV of 95% and NPV of 14%. In comparison between conventional CT and PET/CT studies, the PET/CT diagnosed local tumor recurrence in 16 patients (32%), while CT scan diagnosed local tumor recurrence in only 3 patients (6%), and PET/CT detected peritoneal recurrence in 34 patients (68%). CT scan found peritoneal deposits in 11 patients (22%), also the PET/CT showed suspicious abdominal LNS in 22 patients (44%) while, CT scan showed suspicious abdominal LNS in 4 patients (8%), and PET/CT showed suspicious pelvic LNS in 16 patients (32%). CT scan showed suspicious pelvic LNS in 7 patients (14%). PET/CT detected distant organ metastases in 18 patients (36%). CT scan detected distant organ metastasis in only 8 patients (16%). Comparison between CT and PET/CT in 32 follow-up cases for the detection of local tumor recurrence, peritoneal deposits, suspicious abdominal/pelvic LNs and distant organ metastasis. There was a statistically significant difference between CT and PET/CT the end results (p < 0.0001, p = 0.0047, p = 0.001, p = 0.03).

Conclusions

18F-FDG-PET/CT is more sensitive in detection and localization of ovarian cancer recurrence and more superior than the other imaging modalities.

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.

The Value of PET-CT in Ovarian Epithelial Carcinoma: A Population-Based Study in British Columbia, Canada

INTRODUCTION

In epithelial ovarian cancer (EOC), consensus regarding optimal use of PET/CT is lacking. Limited evidence suggests its accuracy in preoperative staging, investigating recurrence and predicting optimal secondary debulking. This study evaluated indications for PET/CT, impact of PET/CT results on EOC management, and its added value over conventional imaging.

METHODS

Patients with EOC aged 19 years and older who underwent PET/CT at BC Cancer Vancouver between January 2007 and September 2017 were eligible. Medical records were retrospectively reviewed with the following data abstracted: patient demographics, PET/CT indications and results, recent conventional imaging results, and application of PET/CT findings. Basic descriptive analysis was performed to determine most common use of PET/CT and its management impact.

RESULTS

257 PET/CTs in 216 patients were eligible. Most PET/CTs (135/257, 52.6%) were performed for suspected disease recurrence/progression. Management after PET/CT changed in 1/3 of cases with the greatest impact seen when assessing suitability in recurrent disease for focal radiotherapy or secondary surgical debulking. For 106/257 cases with recent conventional imaging available, although differences in disease extent were found in ~50%, clinical conclusions drawn were the same in ~75%.

DISCUSSION

Although PET/CT is most commonly used to investigate suspected recurrence/progression, its impact on management here is low. Greater impact is seen when considering localized therapy in EOC recurrence. When compared with recent conventional imaging, although PET/CT may detect differences in disease extent, clinical conclusions are frequently the same.

CONCLUSION

Impact of PET/CT on management is greatest in EOC recurrence when considering local therapies, beyond which clinical presentation and conventional imaging may suffice.

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.

The Prognostic Value of 18F-FDG PET/CT in Monitoring Chemotherapy in Ovarian Cancer Both at Initial Diagnosis and at Recurrent Disease

Published experiences related to the prognostic relevance of negative or positive FDG PET/CT in patients treated for ovarian cancer for progression-free survival and overall survival are typically heterogeneous retrospective analyses. Several points have been well defined, these are as follows: (a) there is a correlation between FDG tumor uptake and prognosis; (b) ovarian cancer patients treated by neoadjuvant or adjuvant chemotherapy can be divided into responders with reduction in tumor FDG uptake during and after treatment and nonresponders where tumor FDG uptake remains stable or increases after treatment;

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.

FDG-PET/CT in the Postoperative Period: Utility, Expected Findings, Complications, and Pitfalls

FDG-PET/CT as a modality is increasingly used for detection of recurrence and for restaging in patients with clinical suspicion of malignancy, as well as in patients with elevated tumor markers. However, there are many pitfalls in the interpretation of these scans when the studies are performed after some treatment. Some of these are attributed to normal physiological distribution and are compounded when there are inflammatory changes occurring after surgery. The body's inherent response to the surgical insult results in this inflammation. In addition, there are also complications that can happen following surgery, causing increased FDG uptake. Despite various fallacies, FDG-PET/CT provides valuable information in evaluation of residual and recurrent malignant disease. In this article, we aim to describe some of these postsurgical changes secondary to inflammation, common surgical complications, and finally, the utility of FDG-PET/CT in these patients to detect recurrent disease, even in the background of postsurgical changes.

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.

Diagnostic value of positron emission tomography (PET) and PET/computed tomography in recurrent/metastatic ovarian cancer: A meta-analysis

AIM

The study was conducted to assess and compare the overall diagnostic value of positron emission tomography (PET) alone and PET/computed tomography (CT) for the detection of recurrent/metastatic ovarian cancer.

METHODS

A systematic literature search in PubMed, EMBASE and Chinese literature databases (CNKI, VIP and Wanfang) up to August 2014 was performed to identify relevant articles. The diagnostic performance of PET alone or PET/CT was assessed in terms of the following evaluation indexes: summary sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio and area under the curve summary receiver operating characteristics.

RESULTS

Sixty-four studies with 3722 patients were included in this meta-analysis. Favorable results were obtained for both PET/CT and PET alone with similar sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio and area under the curve in diagnosing recurrent/metastatic ovarian cancer (P > 0.05). However, the sensitivity of PET/CT was significantly higher than PET alone in European patients.

CONCLUSIONS

Both PET and PET/CT have promising diagnostic value in recurrent/metastatic ovarian cancer. The diagnostic performance of PET/CT may be superior to PET alone in European patients.

Diagnostic and prognostic evaluation of fluorodeoxyglucose positron emission tomography/computed tomography and its correlation with serum cancer antigen-125 (CA125) in a large cohort of ovarian cancer patients

OBJECTIVE

We evaluated the efficacy of 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in recurrent disease, response to therapy, and long-term follow-up of ovarian cancer (OC) patients in relation to cancer antigen-125 (CA125) levels and the prognostic meaning of this modality in this subset of subjects.

MATERIAL AND METHODS

Between 2005 and 2015, we retrospectively evaluated 125 patients affected by OC who underwent FDG PET/CT imaging at our institution. The indications for PET/CT were recurrence of disease in 78 patients, therapy response assessment in 29, and follow-up in 18. The results of FDG PET/CT were compared with those of histopathology and clinical and radiological progression during follow-up for at least 6 months. The median long-term follow-up was 33 months. The diagnostic accuracies for the different clinical settings were evaluated. The relationships among global survival (GS), FDG PET/CT results, and CA125 levels were evaluated by both Kaplan-Meier and Cox regression analysis.

RESULTS

CA125 results were positive (>35 UI/mL) in 62 patients and negative in 63 (49% vs. 51%). The sensitivity and specificity of CA125 were 72% and 91%, respectively. PET/CT imaging showed a sensitivity of 98.6% and a specificity of 77.8% for the assessment of recurrent disease, and a sensitivity of 72.7% and a specificity of 88.9% for therapy evaluation. Meanwhile, in 18 patients evaluated during follow-up, the specificity was 82.3%. GS was significantly higher in case of negative CA125 values at the time of FDG PET/CT, of a negative PET/CT scan and when no evidence of peritoneum recurrence and distant metastases was determined by PET. Multivariate regression analysis showed that only age and peritoneum recurrence as determined by PET were identified as independent predictors of poor prognosis.

CONCLUSION

Metabolic imaging with FDG PET/CT proved useful in patients where OC recurrence was suspected, even when the value of tumor marker CA125 was in a normal range. A positive PET/CT scan and the presence of peritoneum recurrence at PET were associated with a poor prognosis after approximately 30 months.

Gynecologic oncologic imaging with PET/CT

FDG-PET/CT has been evaluated in a variety of gynecologic malignancies in a variety of settings and is approved by the Centers for Medicare & Medicaid Services for the initial and subsequent treatment strategies of these malignancies. Cervical cancer is typically very FDG avid, and FDG-PET/CT appears to be most valuable for initial staging, radiation therapy planning, and detection of recurrent disease. For ovarian cancer, the most value of FDG-PET/CT appears to be for detecting recurrent disease in the setting of rising CA-125 level and negative or equivocal anatomical imaging studies. Initial studies evaluating response to therapy are promising and further work in this area is needed. FDG uptake in both nonmalignant and physiological processes in the pelvis can make interpretation of FDG-PET/CT in this region challenging and knowledge of these entities and patterns can avoid misinterpretation. Some of the most common findings relate to the cyclic changes that occur as part of the menstrual cycle in premenopausal women. Mucinous tumors and low-volume or peritoneal carcinomatosis are causes of false-negative results on FDG-PET/CT studies. As new tracers are developed, comparisons with patient outcomes and standards of care (eg, FDG-PET/CT) will be needed.

Evaluation of follow-up strategies for patients with epithelial ovarian cancer following completion of primary treatment

BACKGROUND

Ovarian cancer is the sixth most common cancer and seventh commonest cause of death in women worldwide. Traditionally, many people who have been treated for cancer undergo long-term follow-up in secondary care. However, it has been suggested that the use of routine review may not be effective in improving survival, quality of life (QoL), or relieving anxiety, or both. In addition, traditional follow-up may not be cost-effective.

OBJECTIVES

To compare the potential benefits of different strategies of follow-up in patients with epithelial ovarian cancer following completion of primary treatment.

SEARCH METHODS

For this update we searched the Cochrane Gynaecological Cancer Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) Issue 7, 2013, MEDLINE and EMBASE from November 2010 to July 2013. We also searched reference lists of review articles and contacted experts in the field.

SELECTION CRITERIA

All relevant randomised controlled trials (RCTs) that evaluated follow-up strategies for women with epithelial ovarian cancer following completion of primary treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently abstracted data and assessed risk of bias.

MAIN RESULTS

The authors did not identify any new studies that were eligible for inclusion in this update of the review. The search for the original review identified only one RCT that met the inclusion criteria, which included 529 women. This study reported data on immediate treatment of ovarian cancer relapse following rise of serum CA125 levels versus delaying treatment until symptoms developed. All the women participating had previous confirmation of remission, with normal CA125 concentration and no radiological evidence of disease, after surgery and first-line chemotherapy for ovarian cancer.Overall survival between the immediate and delayed arms showed no difference after a median follow-up of 56.9 months (unadjusted hazard ratio (HR) 0.98, 95% confidence interval (CI) 0.80 to 1.20; P value 0.85). Time from randomisation to first deterioration in global health score or death was shorter in the immediate treatment group than in the delayed treatment group (HR 0.71, 95% CI 0.58 to 0.88; P value < 0.01). The trial was at low risk of bias.

AUTHORS' CONCLUSIONS

Limited evidence from a single trial suggests that routine surveillance with CA125 in asymptomatic patients and treatment at CA125 relapse does not seem to offer survival advantage when compared to treatment at symptomatic relapse. RCTs are needed to compare different types of follow-up, looking at survival, QoL, cost and psychological effects as outcomes.

Impact of FDG PET in optimizing patient selection for cytoreductive surgery in recurrent ovarian cancer

PURPOSE

To investigate the impact of PET and PET/CT scanning on decision-making in management planning and to identify the optimal setting for selecting candidates for surgery in suspicious recurrent ovarian cancer.

METHODS

A retrospective chart review was performed in patients with possible recurrent ovarian cancer after primary optimal cytoreduction and taxane/carboplatin chemotherapy who had undergone FDG PET or FDG PET/CT scans from July 2002 to August 2008 to help make treatment decisions. The analysis included 44 patients who had undergone a total of 89 PET scans. The positive PET scans were classified as follows. (1) localized (one or two localized sites of FDG uptake), (2) multiple (three or more sites of FDG uptake), (3) diffuse (extensive low-grade activity outlining serosal and peritoneal surfaces).

RESULTS

Of the 89 PET scans, 52 (58.4%) led to a change in management plan. The total number of patients in whom cytoreductive surgery was selected as the treatment of choice increased from 12 to 35. Miliary disseminated disease, which was not detected by PET scan, was found in 22.2% of those receiving surgery. Miliary disseminated disease was detected in 6 of the 12 patients with recurrent disease whose treatment-free interval (TFI) was <12 months, whereas none of those with a TFI of ≥12 months had such disease (P = 0.0031).

CONCLUSION

PET or PET/CT is useful for selecting candidates for cytoreductive surgery among patients with recurrent ovarian cancer. To avoid surgical attempts in those with miliary dissemination, patients with a TFI of ≥12 months are the best candidates for cytoreductive surgery.

Impact of FDG-PET and -PET/CT imaging in the clinical decision-making of ovarian carcinoma: an evidence-based approach

The most definitive role of fluorodeoxyglucose (FDG)-PET/computed tomography (CT) at present is surveillance and detecting recurrence in patients who have completed primary therapy but demonstrate a rising serum tumor marker (e.g., CA-125 levels). In this scenario, PET/CT demonstrates high sensitivity and accuracy in detecting lesions that are otherwise challenging, and appears superior (with less interobserver variability) compared with CT alone. Despite the fact that peritoneal deposits may be missed by PET/CT, the overall performance is better than CT alone. FDG-PET does not play a significant additional role in the primary diagnosis of ovarian cancers; however, the role of combined PET/CT modality has recently begun to be re-explored for initial disease staging, particularly because PET/CT can pick up small unsuspected lesions and thereby provide a better disease assessment of the whole body in a single examination. The baseline PET/CT also subserves an important role for future monitoring of therapy response. Therapy monitoring by PET could help to optimize neoadjuvant therapy protocols and to avoid ineffective therapy in nonresponders early in its course, although PET/CT has cost-effectiveness issues that need further evaluation. The prognostic value of FDG-PET/CT has been investigated in the following areas: in the preoperative setting to predict optimal cytoreduction; to assess the value of a positive FDG-PET following primary surgery; and when employed as a replacement for second-look laparotomy following completion of primary surgery and chemotherapy. The data, although promising, are still sparse in all the three domains for a definite recommendation.

Low-dose non-enhanced CT versus full-dose contrast-enhanced CT in integrated PET/CT scans for diagnosing ovarian cancer recurrence

OBJECTIVE

To evaluate low-dose non-enhanced CT (ldCT) and full-dose contrast-enhanced CT (ceCT) in integrated 18F-fluorodeoxyglucose (FDG)-PET/CT studies for restaging of ovarian cancer.

MATERIALS AND METHODS

One hundred and twenty women who had undergone treatment for ovarian cancer underwent a conventional PET/CT scans with ldCT, and then ceCT. Two observers interpreted and decided in consensus on the PET/ldCT and PET/ceCT images by a 3-point scale (N: negative, E: equivocal, P: positive) per patient and lesion site. Final diagnoses were obtained by histopathological examinations, or clinical follow-up for at least 6 months.

RESULTS

Patient-based analysis showed that the sensitivity, specificity, and accuracy of PET/ceCT was 86.9% (40/46), 95.9% (71/74), and 92.5% (111/120), respectively, whereas those of PET/ldCT were 78.3% (36/46), 95.0% (70/74), and 88.3% (106/120), respectively. All sensitivity, specificity, and accuracy significantly differed between two methods (McNemar test, p<0.0005, p=0.023, and p<0.0001, respectively). The scales of detecting 104 recurrent lesion sites were N:14, E:6, P:84 for PET/ceCT, and N:15, E:17, P:72 for PET/ldCT, respectively. Eleven equivocal and one negative regions by PET/ldCT were correctly interpreted as positive by PET/ceCT.

CONCLUSION

PET/ceCT is a more accurate imaging modality with higher confidence for assessing ovarian cancer recurrence than PET/ldCT.

The role of FDG-PET/CT in gynaecological cancers

There is now a growing body of evidence supporting the use of fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in gynaecological malignancies. Although this molecular imaging technique is becoming increasingly available, PET/CT remains an expensive imaging tool. It is essential to be familiar with the circumstances in which FDG-PET/CT can add value and contribute to patient management and indeed to know when it is unlikely to be of benefit. It is also important to understand and recognize the potential pitfalls. FDG-PET/CT has been most widely adopted for staging patients with suspected advanced disease or in suspected recurrence, offering a whole-body imaging approach. However, there is great potential for this technique to act as a predictive biomarker of response to treatment, as well as a prognostic biomarker. In addition, FDG-PET images may now be incorporated into radiotherapy planning in order to refine the delineation of dose according to metabolically active sites of disease. This article reviews the literature that provides the evidence for the use of FDG-PET in gynaecological malignancies, identifies areas of real benefit and future potential, and highlights circumstances where there is limited value.

PET/CT imaging in gynecologic malignancies: a critical overview of its clinical impact and our retrospective single center analysis

Gynecologic cancers represent a major global healthcare problem since they are associated with a significant mortality and morbidity. Over the last decade, considerable efforts have been spent in the development and optimization of novel diagnostic modalities to achieve an early diagnosis, aid in choosing appropriate treatment, improving long term surveillance, with the ultimate goal of increasing survival of gynecologic cancer patients. A growing body of evidence defines PET/CT as one of the most powerful tools for tumor, nodal and metastasis (TNM) cancer staging both in pre-treatment and in post treatment follow-up settings. At any phase of cancer evaluation, detection of metastasis represents one of the most critical impediments to the cure of tumor; traditional diagnostic imaging modalities, such as computed tomography (CT), are frequently found to inadequately stage the tumor, based on subsequent outcomes. As a consequence, patients may undergo pointless surgery for disease that could be treated with local medical therapies. In the setting of restaging, the ability to describe primary lesion, lymph nodes, possible metastases to peritoneum, bone, liver, lungs and brain renders PET/CT a potential alternative for a series of tests, including bone scanning, MRI or ultrasound, diagnostic CT, lymph node surgical sampling, that need to be used in combination in order to obtain a level of clinical confidence. In this review, we describe, the theoretical advantage and prognostic implications of PET/CT in the management of gynecologic cancer patients.

Evaluation of follow-up strategies for patients with epithelial ovarian cancer following completion of primary treatment

BACKGROUND

Ovarian cancer is the sixth most common cancer and seventh cause of cancer death in women worldwide. Traditionally, many patients who have been treated for cancer undergo long-term follow up in secondary care. Recently however it has been suggested that the use of routine review may not be effective in improving survival, quality of life (QoL), and relieving anxiety. In addition, it may not be cost effective.

OBJECTIVES

To compare the potential benefits of different strategies of follow up in women with epithelial ovarian cancer following completion of primary treatment.

SEARCH STRATEGY

We searched the Cochrane Gynaecological Cancer Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2010, Issue 4), MEDLINE and EMBASE (to November 2010). We also searched CINAHL, PsycLIT, registers of clinical trials, abstracts of scientific meetings, reference lists of review articles, and contacted experts in the field.

SELECTION CRITERIA

All relevant randomised controlled trials (RCTs) that evaluated follow-up strategies for patients with epithelial ovarian cancer following completion of primary treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently abstracted data and assessed risk of bias.

MAIN RESULTS

We found only one RCT (Rustin 2010) that met our inclusion criteria. This trial included 529 women and reported data on immediate treatment versus delayed treatment in women with confirmation of remission and with normal CA125 concentration and no radiological evidence of disease after surgery and first-line chemotherapy.Overall survival showed no significant difference between the immediate and delayed arms after a median follow up of 56.9 months (unadjusted hazard ratio (HR) = 0·98, 95% confidence interval (CI) 0·80 to 1·20; P = 0·85). Time from randomisation to first deterioration in global health score or death was significantly shorter in the early group compared with the delayed group (HR 0·71, 95% CI 0·58 to 0·88; P < 0·01). The trial was at low risk of bias.

AUTHORS' CONCLUSIONS

There is a lack of randomised studies on most aspects of follow-up care after treatment for epithelial ovarian cancers. Limited evidence from a single trial suggests that routine surveillance with CA125 in asymptomatic patients, with treatment at CA125 relapse, does not seem to offer survival advantage when compared to treatment at symptomatic relapse. Randomised controlled trials are needed to compare different types of follow up on the outcomes of survival, quality of Life, cost and psychological effects.

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.

How to follow-up patients with epithelial ovarian cancer

PURPOSE OF REVIEW

Despite optimal primary treatment most patients with advanced epithelial ovarian cancer will relapse. This review discusses the controversy regarding surveillance and the timing of treatment for recurrent disease.

RECENT FINDINGS

Routine physical examination has a limited role in the detection of recurrent ovarian cancer. PET/computed tomography (CT) has been shown to be useful in detecting small volume disease not apparent on traditional imaging in patients with suspected recurrence based on symptoms and/or rising CA125. The results of PET/CT can alter treatment plans and have particular use in guiding site-directed therapy. The benefits of early detection and systemic treatment of recurrence are now in doubt following the presentation of the MRC/EORTC CA125 surveillance trial. The impact on survival of secondary cytoreductive surgery requires more investigation.

SUMMARY

Uncertainties remain in the surveillance and timing of treatment for relapsed disease. Patients should be informed of these uncertainties and become involved in decisions regarding their follow-up.

A systematic review of PET and PET/CT in oncology: a way to personalize cancer treatment in a cost-effective manner?

BACKGROUND

A number of diagnostic tests are required for the detection and management of cancer. Most imaging modalities such as computerized tomography (CT) are anatomical. However, positron emission tomography (PET) is a functional diagnostic imaging technique using compounds labelled with positron-emitting radioisotopes to measure cell metabolism. It has been a useful tool in studying soft tissues such as the brain, cardiovascular system, and cancer. The aim of this systematic review is to critically summarize the health economic evidence of oncologic PET in the literature.

METHODS

Eight electronic databases were searched from 2005 until February 2010 to identify economic evaluation studies not included in previous Health Technology Assessment (HTA) reports. Only full health economic evaluations in English, French, or German were considered for inclusion. Economic evaluations were appraised using published quality criteria for assessing the quality of decision-analytic models. Given the variety of methods used in the health economic evaluations, the economic evidence has been summarized in qualitative form.

RESULTS

From this new search, 14 publications were identified that met the inclusion criteria. All publications were decision-analytic models and evaluated PET using Fluorodeoxyglucose F18 (FDG-PET). Eight publications were cost-effectiveness analyses; six were cost-utility analyses. The studies were from Australia, Belgium, Canada, France, Italy, Taiwan, Japan, the Netherlands, the United Kingdom, and the United States. In the base case analyses of these studies, cost-effectiveness results ranged from dominated to dominant. The methodology of the economic evaluations was of varying quality. Cost-effectiveness was primarily influenced by the cost of PET, the specificity of PET, and the risk of malignancy.

CONCLUSIONS

Owing to improved care and less exposure to ineffective treatments, personalized medicine using PET may be cost-effective. However, the strongest evidence for the cost-effectiveness of PET is still in the staging of non-small cell lung cancer. Management decisions relating to the assessment of treatment response or radiotherapy treatment planning require further research to show the impact of PET on patient management and its cost-effectiveness. Because of the potential for increased patient throughput and the possible greater accuracy, the cost-effectiveness of PET/CT may be superior to that of PET. Only four studies of the cost-effectiveness of PET/CT were found in this review, and this is clearly an area for future research.

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.

Recurrent ovarian cancer: use of contrast-enhanced CT and PET/CT to accurately localize tumor recurrence and to predict patients' survival

PURPOSE

To compare accuracy and interobserver variability in the detection and localization of recurrent ovarian cancer with contrast material-enhanced (CE) computed tomography (CT) and positron emission tomography (PET)/CT and determine whether imaging findings can be used to predict survival.

MATERIALS AND METHODS

Waiving informed consent, the institutional review board approved this HIPAA-compliant, retrospective study of 35 women (median age, 54.4 years) with histopathologically proven recurrent ovarian carcinoma who underwent CE CT and PET/CT before exploratory surgery. All CE CT and PET/CT scans were independently analyzed. Tumor presence, number of lesions, and the size and maximum standardized uptake value (SUV(max)) of the largest lesion were recorded for patient and region. Surgical histopathologic findings constituted the reference standard. Areas under the receiver operating characteristic curves (AUCs), κ statistics, and hazard ratios were calculated.

RESULTS

Readers' AUCs in detection of recurrence for region were 0.85 (95% confidence interval [CI]: 0.81, 0.90) and 0.78 (95% CI: 0.72, 0.83) for CE CT and 0.84 (95% CI: 0.79, 0.89) and 0.74 (95% CI: 0.67, 0.81) for PET/CT (P = .76); 12 patients died. At PET/CT, size, number, and SUV(max) of peritoneal deposits were significantly associated with poor survival for readers 1 and 2 (P ≤ .01and ≤ .05, respectively), as were long- and short-axis diameters, number, and SUV(max) of distant lymph nodes for reader 1 (P ≤ .001). With CE CT, size (reader 1) and number (readers 1 and 3) of peritoneal deposits were significantly associated with poor survival (P ≤ .01), as were long- and short-axis diameters and number of distant lymph nodes for reader 1 (P ≤ .01). Interobserver agreement ranged from fair (patient, κ = 0.30) to moderate (region, κ = 0.55) for CE CT and fair (patient, κ = 0.24) to substantial (region, κ = 0.63) for PET/CT.

CONCLUSION

Preliminary data suggest that CE CT and PET/CT may have similar accuracy in detection of recurrent ovarian cancer. Tumor size, number, and SUV(max) may have potential as prognostic biomarkers for patients with recurrent ovarian cancer.

Role of PET/CT in ovarian cancer

OBJECTIVE

The purpose of this article is to review the role of FDG PET/CT in ovarian cancer, which is the leading cause of death among gynecologic cancers.

CONCLUSION

FDG PET/CT can significantly modify the assessment of the extent of primary and recurrent ovarian cancer and, hence, often alters patient management substantially. FDG PET/CT has thus become a critical tool for the preoperative evaluation of women with primary ovarian cancer and for postoperative follow-up assessment for evidence of recurrence in these patients.

Hybrid imaging (SPECT/CT and PET/CT): improving therapeutic decisions

The incremental diagnostic value of integrated positron emission tomography-computed tomography (PET/CT) or single-photon emission computed tomography (SPECT)/CT images compared with PET or SPECT alone, or PET or SPECT correlated with a CT obtained at a different time includes the following: (1) improvement in lesion detection on both CT and PET or SPECT images, (2) improvement in the localization of foci of uptake resulting in better differentiation of physiological from pathologic uptake, (3) precise localization of the malignant foci, for example, in the skeleton vs soft tissue or liver vs adjacent bowel or node (4) characterization of serendipitous lesions, and (5) confirmation of small, subtle, or unusual lesions. The use of these techniques can occur at the time of initial diagnosis, in assessing the early response of disease to treatment, at the conclusion of treatment, and in continuing follow-up of patients. PET/CT and SPECT/CT fusion images affect the clinical management in a significant proportion of patients with a wide range of diseases by (1) guiding further procedures, (2) excluding the need of further procedures, (3) changing both inter- and intramodality therapy, including soon after treatment has been initiated, and (4) by providing prognostic information. PET/CT fusion images have the potential to provide important information to guide the biopsy of a mass to active regions of the tumor and to provide better maps than CT alone to modulate field and dose of radiation therapy. It is expected that the role of PET/CT and SPECT/CT in changing management will continue to evolve in the future and that these tools will be fundamental components of the truly "personalized medicine" we are striving to deliver.

Diagnosis and staging of primary ovarian cancer: correlation between PET/CT, Doppler US, and CT or MRI

PURPOSE

To compare the diagnostic accuracy of positron emission tomography/computed tomography (PET/CT), pelvic Doppler ultrasonography (US), abdomino-pelvic computed tomography (CT), and pelvic magnetic resonance imaging (MRI) for detection of ovarian cancer and to assess the role of PET/CT in evaluating the dissemination of ovarian cancer.

PATIENTS AND METHODS

One hundred thirty-three women suspected to have ovarian cancer were enrolled in a prospective study before surgery between March 2005 and August 2007. The accuracy of each modality in detection of malignancy was estimated by computing the relevant areas under a receiver operating characteristics curve. Histopathologic results served as the reference standard.

RESULTS

Histopathology showed benign tumors in 25 patients, borderline tumors in 13 patients, and malignant tumors in 95 patients. In distinguishing malignant/borderline from benign ovarian tumors, the accuracy of PET/CT (0.921) was higher than that of pelvis US (0.830) and abdomino-pelvic CT or pelvis MRI (0.749; P=0.013). Radiologic staging by PET/CT was concordant with surgical staging in 78% of patient and PET/CT revealed 15 (15.8%) unpredicted extra-abdominal lymph node metastasis in 95 patients with ovarian cancer. In addition, PET/CT detected new, unexpected co-existing malignant tumors in five (3.8%) cases including two thyroid tumors, two breast tumors, and one pancreatic neuroendocrine cancer.

CONCLUSION

PET/CT is superior to pelvis US, abdomino-pelvic CT, and pelvic MRI for diagnosis of malignant ovarian tumors and is useful in revealing metastatic ovarian cancer and co-existing malignant tumors. Therefore, we suggest that PET/CT could be used during pre-operative evaluation of patients suspected to have ovarian cancer.