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

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.

18F-FDG PET/MRI and 18F-FDG PET/CT for the Management of Gynecological Malignancies: A Comprehensive Review of the Literature

OBJECTIVE

Positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro- D-glucose integrated with computed tomography (18F-FDG PET/CT) or magnetic resonance imaging (18F-FDG PET/MRI) has emerged as a promising tool for managing various types of cancer. This review study was conducted to investigate the role of 18F- FDG PET/CT and FDG PET/MRI in the management of gynecological malignancies.

SEARCH STRATEGY

We searched for relevant articles in the three databases PubMed/MEDLINE, Scopus, and Web of Science.

SELECTION CRITERIA

All studies reporting data on the FDG PET/CT and FDG PET MRI in the management of gynecological cancer, performed anywhere in the world and published exclusively in the English language, were included in the present study.

DATA COLLECTION AND ANALYSIS

We used the EndNote software (EndNote X8.1, Thomson Reuters) to list the studies and screen them on the basis of the inclusion criteria. Data, including first author, publication year, sample size, clinical application, imaging type, and main result, were extracted and tabulated in Excel. The sensitivity, specificity, and diagnostic accuracy of the modalities were extracted and summarized.

MAIN RESULTS

After screening 988 records, 166 studies published between 2004 and 2022 were included, covering various methodologies. Studies were divided into the following five categories: the role of FDG PET/CT and FDG-PET/MRI in the management of: (a) endometrial cancer (n = 30); (b) ovarian cancer (n = 60); (c) cervical cancer (n = 50); (d) vulvar and vagina cancers (n = 12); and (e) gynecological cancers (n = 14).

CONCLUSIONS

FDG PET/CT and FDG PET/MRI have demonstrated potential as non-invasive imaging tools for enhancing the management of gynecological malignancies. Nevertheless, certain associated challenges warrant attention.

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.

Molecular Imaging of Peritoneal Carcinomatosis in Ovarian Carcinoma

OBJECTIVE. This article discusses the emerging roles of ¹⁸F-FDG PET/CT and DWI in the assessment of peritoneal carcinomatosis in ovarian carcinoma from diagnostic accuracy to disease prognostication with gross pathologic correlation. CONCLUSION. PET/CT and DWI have incremental clinical values over conventional modalities with high predictive values of incomplete cytoreduction in ovarian carcinoma. The respective quantitative metrics offer evaluation of tumor burden with prognostic value in ovarian carcinoma.

Metabolic active peritoneal sites affect tumor debulking in ovarian and peritoneal cancers

Rationale and objectives

To evaluate the impact of metabolic parameters in the peritoneal cavity on the likelihood of achieving complete tumor debulking in patients with ovarian and peritoneal cancers.

Materials and methods

Forty-nine patients with ovarian and peritoneal cancers were included, who underwent pre-operative ¹⁸F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (¹⁸F-FDG PET/CT). The immediate surgical outcome was dichotomized into complete and incomplete tumor debulking. ¹⁸F-FDG PET/CT was qualitatively and quantitatively assessed by scrutinizing 15 anatomical sites for the presence of peritoneal carcinomatosis (PC). Patient-based and site-based diagnostic characteristics were described. Metabolic parameters (SUVmax, metabolic tumor volume and total lesion glycolysis) and the number of ¹⁸F-FDG avid peritoneal sites were evaluated between the two groups. Receiver operating curve (ROC) analysis was performed to determine the optimal cut-off value in predicting incomplete tumor debulking.

Results

Twenty-seven out of the 49 patients had PC and 11 had incomplete debulking. Patient-based and site-based accuracies for detection of PC were 87.8 and 97.6%, respectively. The number of ¹⁸F-FDG avid peritoneal sites was significantly different between complete and incomplete debulking groups (0.6 ± 0.8 versus 2.3 ± 1.7 sites respectively, p = 0.001), and the only independent significant risk factor among other metabolic parameters tested (odd ratio = 2.983, 95% CI 1.104–8.062) for incomplete tumor debulking with an optimal cut-off value of ≥4 (AUC = 0.816).

Conclusion

The number of ¹⁸F-FDG avid peritoneal sites increased the risk of incomplete tumor debulking after surgery and potentially useful in assisting treatment stratification in patients with ovarian and peritoneal cancers.

Functional tumour burden of peritoneal carcinomatosis derived from DWI could predict incomplete tumour debulking in advanced ovarian carcinoma

OBJECTIVES

To investigate the predictive value of peritoneal carcinomatosis (PC) quantification by DWI in determining incomplete tumour debulking in ovarian carcinoma (OC).

METHODS

Prospective patients with suspected stage III-IV or recurrent OC were recruited for DWI before surgery. PC on DWI was segmented semi-automatically by k-means clustering, retaining voxels with intermediate apparent diffusion coefficient (ADC) to quantify PC burden. A scoring system, functional peritoneal cancer index (fPCI), was proposed based on the segmentation of tumour volume in 13 abdominopelvic regions with additional point given to involvement of critical sites. ADC of the largest PC was recorded. The surgical complexity and outcomes (complete vs. incomplete tumour debulking) were documented. fPCI was correlated with surgical PCI (sPCI), surgical complexity, and its ability to predict incomplete tumour debulking.

RESULTS

Fifty-three patients with stage III-IV or recurrent OC were included with a mean age of 56.1 ± 11.8 years old. Complete tumour debulking was achieved in 38/53 patients (71.7%). Significant correlation was found between fPCI and sPCI (r > 0.757, p < 0.001). Patients with high-fPCI (fPCI ≥ 6) had a high surgical complexity score (p = 0.043) with 84.2% received radical or supra-radical surgery. The mean fPCI was significantly higher in patients with incomplete tumour debulking than in those with complete debulking (10.27 vs. 4.71, p < 0.001). fPCI/ADC combined with The International Federation of Gynecology and Obstetrics stage achieved 92.5% accuracy in predicting incomplete tumour debulking (AUC 0.947).

CONCLUSIONS

DWI-derived fPCI offered a semi-automated estimation of PC burden. fPCI/ADC could predict the likelihood of incomplete tumour debulking with high accuracy.

KEY POINTS

• Functional peritoneal cancer index (fPCI) derived from DWI offered a semi-automated estimation of tumour burden in ovarian carcinoma. • fPCI was highly correlated with surgical PCI (sPCI). • fPCI/ADC could predict the likelihood of incomplete tumour debulking with high accuracy.

Value of [18F]FDG-PET/CT and CA125, serum levels and kinetic parameters, in early detection of ovarian cancer recurrence: Influence of histological subtypes and tumor stages

To assess the diagnostic accuracy of CA125, its kinetic values and positron emission tomography/computed tomography with 2-deoxy-2-[F]fluoro-D-glucose ([F]FDG-PET/CT), in relation with tumor characteristics for suspected recurrence of ovarian cancer. To evaluate the performance of CA125-related parameters as a selection criteria to perform a [F]FDG-PET/CT.A retrospective analysis of 69 [F]FDG-PET/CT for suspected recurrence of ovarian cancer was performed. All patients had 2 measurements of CA125, before PET/CT, to calculate kinetic values, as CA125vel (CA125vel = [CA125a - CA125b]/time) and CA125dt (CA125dt = [log2 × time]/[logCA125a - CA125b]). Maximum standard uptake value (SUVmax) was calculated. The diagnostic accuracy was calculated for all the variables and the optimal cut-off value of each of them by the receiver-operating characteristics (ROC) analysis. All the tests were compared with tumor characteristics and clinical-radiological evolution during follow-up of at least 6 months.Fifty-five cases were diagnosed of recurrence (11 with CA125 <35 U/mL), while 14 showed no disease (11 with CA125 < 35 U/mL). All of them were correctly cataloged by PET/CT. CA125, CA125vel, and SUVmax showed higher levels in recurrent patients (mean 129.54 U/mL, 24.58 U/mL per mo, and 8.69 g/mL, respectively) than in nonrecurrent (mean 20.35 U/mL, 0.60 U/mL per mo, and 0.64 g/mL, respectively). No statistical differences in CA125dt were found. Patients with recurrence of high-grade serous carcinoma (HGSC) showed higher CA125 and CA125vel, without differences in the rest of subtypes and International Federation of Gynecology and Obstetrics stages. The ROC analyses for CA125, CA125vel, and CA125dt showed an area under the curve (AUC) of 0.873 (95% confidence interval [CI] 0.77-0.969), 0.903 (95% CI 0.813-0.994), and 0.727 (95% CI 0.542-0.913), respectively, with an optimal cut-off point of 23.95 U/mL, 4.49 U/mL per mo, and 3.36 months, respectively, while for the SUVmax the AUC was of 0.982 (95% CI 0.948-1.000), and the cut-off point of 2. Multivariate regression analysis identified CA125 and CA125vel as predictors of recurrence.[F]FDG-PET/CT is more accurate than the parameters obtained from the CA125 to detect early recurrence. CA125vel is the most suitable parameter, mainly in HGSC. Levels of CA125vel ≥ 4.49 U/mL per mo facilitate earlier detection by the execution of a [F]FDG-PET/CT. The calculation of these parameters is independent of tumor stage at diagnosis.

Diagnostic value of integrated ¹⁸F-fluoro-2-deoxyglucose positron emission tomography/computed tomography in recurrent epithelial ovarian cancer: accuracy of patient selection for secondary cytoreduction in 134 patients

Objective

The aim of this study was to evaluate the diagnostic value of integrated ¹⁸F-fluoro-2-deoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) for suspected recurrence of epithelial ovarian cancer (EOC) with non-disseminated lesions.

Methods

We retrospectively reviewed the medical records of recurrent EOC patients who underwent secondary cytoreduction from January 2000 to December 2013. A total of 134 patients underwent secondary cytoreduction after imaging with either ¹⁸F-FDG-PET/CT or contrast-enhanced computed tomography (CECT).

Results

In a patient-based analysis of 134 patients, 124 (92.5%) were confirmed to be positive for malignancy. Among 72 patients with suspected non-disseminated recurrence on ¹⁸F-FDG-PET/CT, 65 (89.0%) were confirmed to have recurrence, giving 98.5% sensitivity, 87.7% accuracy, and 88.9% positive predictive value (PPV). In the 65 patients with recurrence, residual tumor remained in 14 patients, giving an accuracy of patient selection for secondary cytoreduction of 69.4% (50/72) and it is higher than that of CECT (64.0%). In 169 lesions removed from patients who underwent preoperative ¹⁸F-FDG-PET/CT, 135 (79.9%) were confirmed to be positive for malignancy and 124 were accurately detected by ¹⁸F-FDG-PET/CT, giving 91.9% sensitivity, 81.1% accuracy, and 85.5% PPV. Foreign body granuloma was found in 33.3% of 21 lesions with false-positive ¹⁸F-FDG-PET/CT findings (7/21). The mean preoperative cancer antigen 125 (CA-125) level in false-positive patients was 28.8 U/mL.

Conclusion

Compared with CECT, ¹⁸F-FDG-PET/CT shows higher sensitivity in lesion-based analysis and better accuracy of patient selection for secondary cytoreduction. However, there is still a need for integration of the results of ¹⁸F-FDG-PET/CT, CECT, and CA-125 levels to aid treatment planning.

An update on the role of PET/CT and PET/MRI in ovarian cancer

This review article summarizes the role of PET/CT and PET/MRI in ovarian cancer. With regard to the diagnosis of ovarian cancer, the presence of FDG uptake within the ovary of a postmenopausal woman raises the concern for ovarian cancer. Multiple studies show that FDG PET/CT can detect lymph node and distant metastasis in ovarian cancer with high accuracy and may, therefore, alter the management to obtain better clinical outcomes. Although PET/CT staging is superior for N and M staging of ovarian cancer, its role is limited for T staging. Additionally, FDG PET/CT is of great benefit in evaluating treatment response and has prognostic value in patients with ovarian cancer. FDG PET/CT also has value to detect recurrent disease, particularly in patients with elevated serum CA-125 levels and negative or inconclusive conventional imaging test results. PET/MRI may beneficial for tumor staging because MRI has higher soft tissue contrast and no ionizing radiation exposure compared to CT. Some non-FDG PET radiotracers such as ¹⁸F-fluorothymidine (FLT) or ¹¹C-methionine (MET) have been studied in preclinical and clinical studies as well and may play a role in the evaluation of patients with ovarian cancer.

PET/MRI Evaluation of Gynecologic Malignancies and Prostate Cancer

PET combined with cross-sectional anatomical imaging is an essential part of workup for most malignancies, in which CT or MRI provides anatomical context to the functional information from PET. Hybrid imaging with PET/CT has been extensively researched and implemented clinically in the evaluation and management of patients with gynecologic malignancies. Lately, integrated PET/MR scanners have become available. This new technology is fast gaining a role in clinical applications in the fields of oncology, neurology, and cardiology. MRI provides excellent soft tissue contrast especially in the pelvis and has been proven very useful for imaging prostate and female genital pathologies. The ability of PET to provide accurate functional imaging data with high sensitivity combined with the strength of MRI to provide accurate depiction of anatomy with high contrast and spatial resolution renders combined PET/MRI a desirable method for evaluation of gynecologic malignancies and other pelvic cancers such as prostate cancer. The goal of this article is to provide an overview of the published literature using PET/MRI in gynecologic and prostate cancers.

Clinical and Survival Impact of FDG PET in Patients with Suspicion of Recurrent Ovarian Cancer: A 6-Year Follow-Up

Background

The aim of this retrospective study was to evaluate the contribution of fluorine-18-fluoro-deoxyglucose (FDG) positron emission tomography (PET) to the clinical management and survival outcome of patients (pts) suspected of recurrent ovarian carcinoma, with the hypothesis that early diagnosis of recurrent ovarian cancer may improve overall survival (OS).

Methods

Fifty-three FDG PET/CT scans were retrospectively analyzed for 42 pts. CT and PET/CT findings were confirmed by imaging and clinical follow-up, and/or pathology, which were considered as the gold standard diagnosis. The treatment plan based on CT staging was compared with that based on PET/CT findings. Medical records were reviewed for pts characteristics, progression-free survival (PFS), and OS. PFS and OS were analyzed using the Cox proportional hazards regression model.

Results

The final diagnosis of recurrence was established pathologically (n = 16), or by a median clinical follow-up of 6.5 years (range 0.5-7.5) after the PET/CT (n = 37). PET/CT provided a higher detection sensitivity (92.2%, 47/51) than CT (60.8%, 31/51) (p < 0.001). Globally, PET/CT modified the treatment plan in 56.6% (30/53) and in 65.2% (15/23) when the CT was negative prior to PET/CT. In 30 cases, those benefited from a modified treatment plan, these changes led to the intensification of a previous treatment procedure in 83.3% (25/30), and to a reduction in the previous treatment procedure in 16.6% of cases (5/30). The Cox regression multivariate analysis showed that the number of lesions visualized by CT and presence of lung lesions detected by PET/CT were significantly associated with PFS (p = 0.002 and p = 0.035, respectively).

Conclusion

On account of its impact on treatment planning, and especially in predicting patient outcome, FDG PET is a valuable diagnostic tool for cases of suspected ovarian cancer recurrence.

Good survival in a patient with recurrent transitional cell carcinoma of the ovary: A case report of PET-CT for detection and follow-up

Transitional cell carcinoma (TCC) of the ovary is a rare subtype of epithelial ovarian cancer. The present study reports the case of a 55-year-old patient from The Affiliated Tumor Hospital of Harbin Medical University (Harbin, Heilongjiang, China) who underwent successful surgery for recurrence of a TCC of the ovary with rectum metastases following the initial surgery and chemotherapy. Positron emission tomography/computed tomography (PET-CT) was used in the pre-operative detection of the tumor and the post-operative follow-up of the patient. To date, the patient has experienced 8 years of disease-free survival. The aim of the present study was to convey the good survival rate of the patient following recurrent TCC of the ovary, and the role of PET-CT in detection and follow-up, in order to aid in the future selection of appropriate diagnostic methods and therapies for this disease.

Fludeoxyglucose F 18 PET-Computed Tomography: Management Changes Effecting Patient Outcomes in Gynecologic Malignancies

Outcome analysis in oncologic imaging is complex because of the multiple variables that can affect survival, including how early disease is diagnosed, the accuracy of staging at diagnosis, and where and how the patient is treated. Risk for tumor recurrence is estimated based on tumor histologic grade, stage at diagnosis, and other factors, including expressed molecular markers. This article reviews the data supporting the use of F 18 fluorodeoxyglucose PET-computed tomography in endometrial, ovarian, and cervical malignancies, with emphasis on the impact of imaging on treatment stratification and prognosis.

Evaluation of (99m)Tc-HYNIC-TMTP1 as a tumor-homing imaging agent targeting metastasis with SPECT

INTRODUCTION

TMTP1 (NVVRQ) is a novel tumor-homing peptide, which specifically targets tumor metastases, even at the early stage of occult metastasis foci. Fusing TMTP1 to therapeutic peptides or proteins can increase its anti-cancer efficacy both in vivo and in vitro. Here, we labeled TMTP1 with (99m)Tc to evaluate its targeting properties in an ovarian cancer xenograft tumor mouse model and a gastric cancer xenograft mouse model.

METHODS

The invasion ability of SKOV3 and highly metastatic SKOV3.ip cell lines were performed by the Transwell Invasion Assays, and then Rhodamine-TMTP1 was used to detect its affinity to these two cells. Using the co-ligand ethylenediamine-N, N'-diacetic acid (EDDA) and the bifunctional chelator 6-hydrazinonicotinic acid (HYNIC), the TMTP1 peptide was labeled with (99m)Tc. A cell-binding assay was performed by incubating cancer cells with (99m)Tc-HYNIC-TMTP1 with or without an excess dose of cold HYNIC-TMTP1. To evaluate the probe in vivo, nude mice bearing SKOV3, SKOV3.ip and MNK-45 tumor cells were established and subjected to SPECT imaging after injection with (99m)Tc-HYNIC-TMTP1. Ex vivo γ-counting of dissected tissues from the mice was used to evaluate its biodistribution.

RESULTS

(99m)Tc-HYNIC-TMTP1 was successfully synthesized. The radiotracer also exhibited high hydrophilicity and excellent stability in vitro and in vivo. It has strong affinity to highly metastatic cancer cell lines but not to poorly metastatic cell lines. After mice were injected with (99m)Tc-HYNIC-TMTP1, non-invasive SPECT imaging detected SKOV3.ip and MNK-45 xenograft tumors but not SKOV3 xenograft tumors. This result can be inhibited by excess HYNIC-TMTP1. The uptake of (99m)Tc-HYNIC-TMTP1 in SKOV3.ip xenograft tumors was 0.182±0.017% ID/g at 2h p.i. with high renal uptake (74.32±15.05% ID/g at 2h p.i.).

CONCLUSION

(99m)Tc-HYNIC-TMTP1 biodistribution and SPECT imaging demonstrated its ability to target highly metastatic tumors. Therefore, metastasis can be non-invasively investigated by SPECT imaging using (99m)Tc-HYNIC-TMTP1. Meanwhile, this radiotracer has some shortages in the low % ID/g of tumors and high accumulation in the kidney.

Positron Emission Tomography (PET) in Oncology

Since its introduction in the early nineties as a promising functional imaging technique in the management of neoplastic disorders, FDG-PET, and subsequently FDG-PET/CT, has become a cornerstone in several oncologic procedures such as tumor staging and restaging, treatment efficacy assessment during or after treatment end and radiotherapy planning. Moreover, the continuous technological progress of image generation and the introduction of sophisticated software to use PET scan as a biomarker paved the way to calculate new prognostic markers such as the metabolic tumor volume (MTV) and the total amount of tumor glycolysis (TLG). FDG-PET/CT proved more sensitive than contrast-enhanced CT scan in staging of several type of lymphoma or in detecting widespread tumor dissemination in several solid cancers, such as breast, lung, colon, ovary and head and neck carcinoma. As a consequence the stage of patients was upgraded, with a change of treatment in 10%-15% of them. One of the most evident advantages of FDG-PET was its ability to detect, very early during treatment, significant changes in glucose metabolism or even complete shutoff of the neoplastic cell metabolism as a surrogate of tumor chemosensitivity assessment. This could enable clinicians to detect much earlier the effectiveness of a given antineoplastic treatment, as compared to the traditional radiological detection of tumor shrinkage, which usually takes time and occurs much later.

Which imaging technique should we use in the follow up of gynaecological cancer?

Follow-up routines after gynaecological cancer vary. The optimal approach is unknown, and no randomised-controlled trials comparing surveillance protocols have been published. In this chapter, we summarise the diagnostic performance of ultrasound, computed tomography, and magnetic resonance imaging in the follow up of women treated for ovarian or uterine cancers. Computed tomography is today the standard imaging method for the follow up of women treated for endometrial, cervical, or ovarian cancer. Six-monthly or annual follow-up examinations have not been shown to positively affect survival. Instead, a combination of transvaginal and transabdominal ultrasound examination with clinical examination might be a more cost-effective strategy for early detection of recurrence. Positron-emission tomography might play a role in women with clinical or serological suspicion of recurrence but without evidence of disease at conventional diagnostic imaging. To create guidelines, more studies, preferably randomised-controlled trials, on follow-up strategies are needed.