Diagnostic value of PET/CT is similar to that of conventional MRI and even better for detecting small peritoneal implants in patients with recurrent ovarian cancer

Cooccurrence of Capsular Liver Lesions Along with Peritoneal Carcinomatosis and Hematogenous Metastases in Ovarian Cancer Patients on Consecutive 18F-FDG PET/CT Studies

Objectives

The aim of our study was to evaluate the cooccurrence of capsular liver lesions along with peritoneal carcinomatosis and hematogenous metastases in other regions of the body in ovarian cancer patients on follow-up F-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) studies.

Methods

Consecutive 18F-FDG PET/CT studies of 54 women with ovarian cancer between August 2012 and January 2020 and a total of 192 scans were analysed retrospectively. All patients had at least one hepatic and/or capsular lesion with high 18F-FDG uptake and at least two PET/CT examinations.

Results

According to interpretation, of 54 patients with hepatic or capsular lesions, 44 (81.4%), 5 (9.3%) and 5 (9.3%) of them were concluded as perihepatic implants, hematogenous liver metastases and both, respectively. Accompanying peritoneal carcinomatosis on follow-up PET/CT images was found in 42 (95.4%) and 3 (60%) patients with solely capsular lesions and solely hematogenous liver metastases, respectively. Extrahepatic hematogenous organ metastases on follow-up PET/CT images were seen in 4 (9.0%) and 3 (60%) patients with solely capsular lesions and solely hematogenous liver metastases, respectively. Lungs, bones, spleen and brain were detected metastases sites.

Conclusion

Cooccurrence of peritoneal carcinomatosis in other regions of abdomen was found to be higher in comparison to hematogenous organ metastases on consecutive PET/CT studies of ovarian cancer patients with capsular liver lesions. The primary opinion of the nuclear medicine physician is essential along with the other patient data for differential diagnosis and treatment approach in this particular patient group.

Prediction of postoperative residual primary ovarian neoplasm or metastatic lesion close to rectum of serous ovarian carcinoma based on clinical and MR T1-DEI features

BACKGROUND

The optimal primary debulking surgery outcome of serous ovarian carcinoma (SOC) is greatly affected by primary ovarian neoplasm or metastatic lesion close to the rectum.

PURPOSE

To study the risk factors affecting postoperative residual primary ovarian neoplasm or metastatic lesion close to the rectum of SOC.

MATERIAL AND METHODS

The clinical and MRI data of 164 patients with SOC eligible from institution A (training and test groups) and 36 patients with SOC eligible from institution B (external validation group) were collected and retrospectively analyzed. The clinical data included age, serum carbohydrate antigen 125 (CA-125), human epididymis protein 4, and neutrophil-to-lymphocyte ratio (NLR). Magnetic resonance imaging (MRI) data included ovarian mass distribution, maximum diameter of ovarian mass, ovarian mass features, degree of rectal invasion of the primary ovarian neoplasm or metastatic lesion, and amount of ascites. A model was established using multivariate logistic regression.

RESULTS

By univariate and multivariate logistic regressions, CA-125 (P = 0.024, odds ratio [OR] = 3.798, 95% confidence interval [CI] = 1.24-13.32), NLR (P = 0.037, OR = 3.543, 95% CI = 1.13-12.72), and degree of rectal invasion of the primary ovarian neoplasm or metastatic lesion (P < 0.001, OR = 37.723, 95% CI = 7.46-266.88) were screened as independent predictors. The area under the curve values of the model in the training, test, and external validation groups were 0.860, 0.764, and 0.778, respectively.

CONCLUSION

The clinical-radiological model based on T1-weighted dual-echo MRI can be used non-invasively to predict postoperative residual ovarian neoplasm or metastasis close to SOC in the rectum.

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.

Peritoneal Carcinomatosis of Malignant Gynecological Origin: A Systematic Review of Imaging Assessment

This systematic review, conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol, aims to comprehensively assess the current state of the art of imaging modalities for the evaluation of peritoneal carcinomatosis arising from malignant gynecological origins, with a focus on ovarian and endometrial cancers. A systematic search of relevant databases was performed, adhering to predetermined inclusion and exclusion criteria. Studies reporting the use of computed tomography (CT), magnetic resonance imaging (MRI), fluorodeoxyglucose (FDG) positron emission tomography (PET), PET/CT, and PET/MRI in the assessment of peritoneal carcinomatosis from gynecological malignancies were included. The review encompasses an overview of selected studies, highlighting the strengths and limitations of each imaging modality in diagnosing and characterizing peritoneal carcinomatosis. Overall, a wide variability in the reported accuracy of different imaging techniques emerges from literature, mainly due to the type of the study, technical issues, and patient characteristics. Although a meta-analysis could not be performed due to a scarcity of data, this systematic review provides valuable insights into the several imaging approaches used in peritoneal carcinomatosis of gynecological origin. The findings aim to inform clinical decision making and guide future research endeavors in this critical aspect of gynecological oncology.

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.

The current role of secondary cytoreductive surgery for recurrent ovarian cancer

Ovarian cancer represents worldwide the second most frequent and the most fatal gynecological malignancy, with approximately two thirds of the patients presenting with advanced disease. Cytoreductive surgery, primary or after neoadjuvant chemotherapy, in combination with platinum-based chemotherapy is the standard of care for these patients. Despite the improvement in quality of cytoreductive surgery as well as development of novel drugs and chemotherapy regimens, still most women with ovarian cancer will ultimately develop recurrent disease and die of their disease. In contrast to the management of primary disease, the standard treatment of patients with recurrent ovarian cancer remains a topic of debate. While platinum-based or second line systemic chemotherapy, depending on the time after last platinum treatment, is standard of care, the role of secondary cytoreductive surgery has been a controversial issue for the last decades. Potential outcome benefit must be also weighed against the risk of severe surgical morbidity, impairment of quality of life and costs. In platinum-resistant recurrent disease, i.e., relapse after less than 6 months from the last platinum-based chemotherapy for primary disease, secondary cytoreduction seems generally not to be indicated due to its aggressive biological behavior and the absence of effective systemic treatment. In this comprehensive review, the current role of cytoreductive surgery in platinum-sensitive recurrent ovarian cancer is discussed thoroughly in view of the results of most recent randomized trials and a meta-analysis. There seems to be definitely a role for secondary cytoreductive surgery in selected patients with ovarian cancer recurrence in whom complete resection of macroscopic disease is feasible. However, its role should be continuously reviewed due to the changing systemic treatment of patients with ovarian cancer recurrence over time.

Magnetic Fields and Cancer: Epidemiology, Cellular Biology, and Theranostics

Humans are exposed to a complex mix of man-made electric and magnetic fields (MFs) at many different frequencies, at home and at work. Epidemiological studies indicate that there is a positive relationship between residential/domestic and occupational exposure to extremely low frequency electromagnetic fields and some types of cancer, although some other studies indicate no relationship. In this review, after an introduction on the MF definition and a description of natural/anthropogenic sources, the epidemiology of residential/domestic and occupational exposure to MFs and cancer is reviewed, with reference to leukemia, brain, and breast cancer. The in vivo and in vitro effects of MFs on cancer are reviewed considering both human and animal cells, with particular reference to the involvement of reactive oxygen species (ROS). MF application on cancer diagnostic and therapy (theranostic) are also reviewed by describing the use of different magnetic resonance imaging (MRI) applications for the detection of several cancers. Finally, the use of magnetic nanoparticles is described in terms of treatment of cancer by nanomedical applications for the precise delivery of anticancer drugs, nanosurgery by magnetomechanic methods, and selective killing of cancer cells by magnetic hyperthermia. The supplementary tables provide quantitative data and methodologies in epidemiological and cell biology studies. Although scientists do not generally agree that there is a cause-effect relationship between exposure to MF and cancer, MFs might not be the direct cause of cancer but may contribute to produce ROS and generate oxidative stress, which could trigger or enhance the expression of oncogenes.

Clinical Applications of PET/MR Imaging

PET/MR imaging is in routine clinical use and is at least as effective as PET/CT for oncologic and neurologic studies with advantages with certain PET radiopharmaceuticals and applications. In addition, whole body PET/MR imaging substantially reduces radiation dosages compared with PET/CT which is particularly relevant to pediatric and young adult population. For cancer imaging, assessment of hepatic, pelvic, and soft-tissue malignancies may benefit from PET/MR imaging. For neurologic imaging, volumetric brain MR imaging can detect regional volume loss relevant to cognitive impairment and epilepsy. In addition, the single-bed position acquisition enables dynamic brain PET imaging without extending the total study length which has the potential to enhance the diagnostic information from PET.

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.

Update on the secondary cytoreduction in platinum-sensitive recurrent ovarian cancer: a narrative review

The ovarian cancer recurrence occurs in 75% of patients with advanced FIGO stage, and its treatment is a challenge for the oncologist in gynecology. The standard treatment of recurrent ovarian cancer (ROC) usually includes intravenous chemotherapy according to platinum sensitivity. Furthermore, maintenance treatment with target therapies [e.g., anti-angiogenic drug or PARP inhibitors (PARPi)], should be provided if not precedently administrated. In this scenario, secondary cytoreductive surgery (SCS) remains a practical but controversial option for platinum-sensitive ROC (PSROC). So far, several retrospective series and a Cochrane meta-analysis had concluded that SCS could determine better survival outcomes in ROC with favorable prognostic characteristics, such as the presence of a single anatomical site of recurrence, or when patients are accurately selected for surgery based on complete resection’s predictive models. Recently, three randomized clinical trials (RCTs) investigated the role of SCS in PSROC patients selected with different criteria. All the three RCTs showed a significant statistical advantage in progression-free survival (PFS) in the SCS group, with an even more significant difference in patients with complete cytoreduction (about 7-month PFS increased). Data on overall survival (OS) are different in the two completed trials. The GOG213 study has documented a longer OS of PSROC patients who received chemotherapy alone compared to surgery plus chemotherapy. Contrarily, the DESKTOP III trial showed 7.7 months of increased OS in the surgery group vs. chemotherapy alone, with a more difference in the complete tumor cytoreduction (CTC) group (12 months). These RCTs thereby suggest that undergoing complete cytoreduction may not be the only key and that the disease biology may also matter. Few recent retrospective series investigated the role of SCS according to BRCA mutation status and the effect of SCS in patients receiving emerging PARPi. A consequence of the developments in SCS and knowledge of different molecular pathways influencing the recurrent disease is that the future research objective should be to individualize and personalize the surgical approach.

Robotic-assisted laparoscopic splenectomy for recurrent ovarian cancer

PURPOSE

Recurrent ovarian cancer frequently involves the spleen. Our aims were to describe the technique of robotic-assisted laparoscopic splenectomy and to evaluate outcomes including progression-free and overall survival in patients who underwent this procedure for recurrent ovarian cancer.

METHODS

Chart reviews were performed on all consecutive patients who underwent robotic splenectomy (April 2012 to May 2019) for recurrent ovarian cancer. Patients had ≤3 sites of disease and no ascites. Extent of disease was confirmed by positron emission tomography-computed tomography (PET-CT) pre-operatively and platinum-doublet chemotherapy was initiated post-operatively. Peri- and post-operative outcomes, progression-free survival, and overall survival were assessed. Two video links are included to demonstrate variations in technique and anatomy.

RESULTS

A total of 10 patients were included. The median age was 63.5 years (range 46-74) and median body mass index was 30 kg/m2 (range 21.5-40.1). Disease was limited to the spleen in seven patients and three had evidence of up to two other sites of disease on imaging. The median robotic splenectomy operative time was 159 min (range 112-214) that included laparoscopic lysis of adhesions prior to robotic port placement in seven cases, and excision of diaphragm or omental implants in three cases. There were no transfusions, laparotomy conversions, return to the operating room, abscesses, or pancreatic pseudocysts. The median length of stay was 2 days (range 1-4). The median time to resumption of chemotherapy was 40 days (range 25-78). After a median follow-up of 51 months (range 12-98), five patients had recurrence (two deaths, three alive with disease), with a median time to recurrence of 14 months (range 12-15). The median progression-free survival was 15 months (range 12-98) and the median overall survival was 51 months (range 12-98) post-splenectomy.

CONCLUSIONS

Robotic splenectomy was feasible, achieving complete cytoreduction of splenic recurrent ovarian cancer, short hospital length-of-stay, and acceptable morbidity.

Visual PET/CT scoring of mesenteric fdg uptake to differentiate between tuberculous peritonitis and peritoneal carcinomatosis

PURPOSE

We aimed to differentiate tuberculous peritonitis (TBP) from peritoneal carcinomatosis (PC) using a visual positron-emission tomography/computed tomography (PET/CT) scoring system based on mesenteric fluorodeoxyglucose (FDG) uptake.

METHODS

PET/CT scans from 31 patients with TBP and 92 patients with PC were retrospectively reviewed. A visual PET/CT scoring system for mesenteric FDG uptake was used according to the following characteristics: FDG uptake intensity (low = 0, moderate = 1, high = 2), FDG uptake deposits (uniform = 0, irregular = 1, ascitic = 2), FDG uptake focality (diffuse = 0, segmental = 1, focal = 2), nodularity on the corresponding CT (nonnodular = 0, micronodular = 1, macronodular = 2) and mesenteric lymphadenopathy (absent = 0, lymphadenopathy without FDG uptake = 1, lymphadenopathy with FDG uptake = 2). The FDG uptake intensity, deposits, focality, nodularity and mesenteric lymphadenopathy scores between TBP and PC were compared using chi-square tests. The diagnostic performance of this scoring system for differentiating TBP from PC was analyzed using a receiver operating characteristic (ROC) curve. P < 0.05 was considered statistically significant.

RESULTS

Twenty-four patients with TBP (77.4%) and 56 patients with PC (60.9%) had mesenteric FDG uptake (P = 0.095) and were included for evaluation with the visual PET/CT scoring system. PC lesions scored higher than TBP lesions in FDG uptake deposits (P < 0.001), focality (P < 0.001) and nodularity (P < 0.001). No significant differences were observed between PC and TBP lesions in FDG uptake intensity (P = 0.396) and lymphadenopathy (P = 0.074). The total score that combined deposits, focality and nodularity had significant value for differentiating TBP from PC (area under the curve (AUC) = 0.869, P < 0.001), and a cutoff > 1 had a sensitivity (the accuracy for diagnosis of PC) of 80.4% and a specificity (the accuracy for diagnosis of TBP) of 75.0%.

CONCLUSION

A visual PET/CT scoring system based on mesenteric FDG uptake performed well in differentiating between TBP and PC.

Imaging for Peritoneal Metastases

MRI provides considerable advantages for imaging of patients with peritoneal tumor. Its inherently superior contrast resolution compared with computed tomography allows MRI to more accurately depict small peritoneal tumors that are often missed on other imaging tests. Combining different contrast mechanisms, including diffusion-weighted MRI and gadolinium-enhanced MRI, provides a powerful tool for preoperative and surveillance imaging in patients being considered for cytoreductive surgery and heated intraperitoneal chemotherapy.

Diagnostic accuracy of 18F-FDG PET/CT for detection of peritoneal carcinomatosis; a systematic review and meta-analysis

OBJECTIVE

The current review aimed to investigate the performance of the diagnostic accuracy of ¹⁸F- fludeoxyglucose positron emission tomography/CT (PET/CT) in detecting peritoneal carcinomatosis (PC) through a systematic review and meta-analysis.

METHODS

The MEDLINE via PubMed and EMBASE from the earliest available date of indexing to 31 March 2017, were searched for studies evaluating the diagnostic performance of ¹⁸F-FDG PET/CT in detecting PC. We evaluated the pooled sensitivities and specificities across included studies, calculated positive and negative likelihood ratios (LR+ and LR-), and plotted summary receiver operating characteristic curves. Deek's funnel plot asymmetry tests were used to assess the possible underlying publication bias.

RESULTS

The current meta-analysis demonstrated no significant publication bias (p = 0.21). Across 14 studies (671 patients), the overall sensitivity of ¹⁸F-FDG PET/CT was 0.87 [95% CI (0.77-0.93)] with heterogeneity (χ² = 94.2, p = 0.00) and a pooled specificity of 0.92 [95% CI; (0.89-0.94)] with heterogeneity (χ² = 20.6, p = 0.08). LR syntheses gave an overall LR+ of 10.4 [95% CI (7.5-14.5)] and LR- of 0.14 [95% CI (0.08-0.26)]. The pooled diagnostic odds ratio was 73 [95% CI (34-159)]. In univariate meta-regression analysis, publication year and cohort homogeneity were the potent sources of heterogeneity. However, in multivariate meta-regression, no definite variable was the source of the study heterogeneity.

CONCLUSION

¹⁸F-FDG PET/CT demonstrated good sensitivity and specificity for the detection of PC. Further large multicentre studies would be necessary to substantiate the diagnostic accuracy of ¹⁸F-FDG PET/CT for the diagnosis of PC in various cancers. Advances in knowledge: ¹⁸F-FDG PET/CT showed good diagnostic performance in the evaluation of PC and could provide additional information for that purpose in various cancers.

Positron emission tomography in the management of documented or suspected recurrent ovarian cancer

BACKGROUND

To prospectively evaluate the value of positron emission tomography (PET) or integrated computed tomography (CT) and PET (PET/CT) in the management of documented or suspected recurrent ovarian cancer.

METHODS

Patients with ovarian cancer who had completed primary cytoreductive surgery and standard adjuvant chemotherapy were studied to evaluate the following indications: (1) CA125 elevation after complete remission with negative CT or magnetic resonance imaging (MRI) result; (2) post-therapy surveillance CT/MRI-detected suspicious lesions that guided biopsy was not feasible; (3) documented relapse for restaging prior to or after curative salvage therapy. The clinical impact of PET, as compared with those of CT/MRI, was determined on a per scan basis.

RESULTS

From 2002 to 2009, 73 patients were recruited, and 92 PET scans were performed. Up to June 2015, 53 patients had died of disease, four were alive with disease, and the remaining 16 were alive without disease. Among the 92 scans, PET had positive impacts in 72.8%, no clinical impacts in 21.7%, and negative impacts in 5.4%. For indication 1, the sensitivity and positive predictive value of PET in detecting recurrence were 80.0% and 92.3%, respectively. For indication 2, the sensitivity, specificity, positive predictive value, and negative predictive value of PET were 91.2%, 62.5%, 91.2%, and 62.5%, respectively. For indication 3, PET provided positive impact in 85.3% and negative impact in 2.9% of the 34 scans.

CONCLUSION

PET has value in the management of suspected or documented recurrent ovarian cancer, with positive impacts on confirming recurrent status and offering a better treatment plan.

The role of 18F-FDG PET CT in common gynaecological malignancies

[fluorine-18]-fluoro-2-deoxy-D-glucose positron emission tomography (¹⁸F-FDG PET CT) has increasing clinical applications supplementing conventional TVUS, CT and MRI imaging in assessing ovarian, cervical and endometrial cancer. The published literature on the applications of ¹⁸F-FDG PET CT shows its use can have significant impact on patient management by improving staging of the cancers, influencing patient selection for treatment and in detecting early recurrent disease. However, the increasing clinical use of PET CT does not always align with the guidelines, recommendations or expert opinion in the use of PET CT. This article summarizes the existing evidence base for the established clinical applications and the emerging roles for ¹⁸F-FDG PET CT in the common gynaecological malignancies.

Can the combined administration of labelled fluoro-2 deoxy d glucose and insulin or chrome increase the diagnostic sensitivity of Positron Emission Tomography (PET)?

In this letter to editor I hypothesize that administering insulin or chrome along with fluoro-2 deoxy d-glucose (FDG) to enhance its uptake in malignant lesions that are known to have low levels of tumor glycolysis, and therefore, improve the sensitivity of PET imaging in this setting. The logic behind this idea stems from the known fact that there is substantial increase in uptake of d-glucose following administration of insülin/chrome in many tissues, and as such, the same pattern would apply to FDG.

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.

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.

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.

Multimodal Magnetic Resonance and Near-Infrared-Fluorescent Imaging of Intraperitoneal Ovarian Cancer Using a Dual-Mode-Dual-Gadolinium Liposomal Contrast Agent

The degree of tumor removal at surgery is a major factor in predicting outcome for ovarian cancer. A single multimodality agent that can be used with magnetic resonance (MR) for staging and pre-surgical planning, and with optical imaging to aid surgical removal of tumors, would present a new paradigm for ovarian cancer. We assessed whether a dual-mode, dual-Gadolinium (DM-Dual-Gd-ICG) contrast agent can be used to visualize ovarian tumors in the peritoneal cavity by multimodal MR and near infra-red imaging (NIR). Intraperitoneal ovarian tumors (Hey-A8 or OVCAR3) in mice enhanced on MR two days after intravenous DM-Dual Gd-ICG injection compared to controls (SNR, CNR, p < 0.05, n = 6). As seen on open abdomen and excised tumors views and confirmed by optical radiant efficiency measurement, Hey-A8 or OVCAR3 tumors from animals injected with DM-Dual Gd-ICG had increased fluorescence (p < 0.05, n = 6). This suggests clinical potential to localize ovarian tumors by MR for staging and surgical planning, and, by NIR at surgery for resection.

Correlation of pre-operative CT findings with surgical & histological tumor dissemination patterns at cytoreduction for primary advanced and relapsed epithelial ovarian cancer: A retrospective evaluation

OBJECTIVES

Computed tomography (CT) is an essential part of preoperative planning prior to cytoreductive surgery for primary and relapsed epithelial ovarian cancer (EOC). Our aim is to correlate pre-operative CT results with intraoperative surgical and histopathological findings at debulking surgery.

METHODS

We performed a systematic comparison of intraoperative tumor dissemination patterns and surgical resections with preoperative CT assessments of infiltrative disease at key resection sites, in women who underwent multivisceral debulking surgery due to EOC between January 2013 and December 2014 at a tertiary referral center. The key sites were defined as follows: diaphragmatic involvement(DI), splenic disease (SI), large (LBI) and small (SBI) bowel involvement, rectal involvement (RI), porta hepatis involvement (PHI), mesenteric disease (MI) and lymph node involvement (LNI).

RESULTS

A total of 155 patients, mostly with FIGO stage IIIC disease (65%) were evaluated (primary=105, relapsed=50). Total macroscopic cytoreduction rates were: 89%. Pre-operative CT findings displayed high specificity across all tumor sites apart from the retroperitoneal lymph node status, with a specificity of 65%. The ability however of the CT to accurately identify sites affected by invasive disease was relatively low with the following sensitivities as relating to final histology: 32% (DI), 26% (SI), 46% (LBI), 44% (SBI), 39% (RI), 57% (PHI), 31% (MI), 63% (LNI).

CONCLUSION

Pre-operative CT imaging shows high specificity but low sensitivity in detecting tumor involvement at key sites in ovarian cancer surgery. CT findings alone should not be used for surgical decision making.

Prognostic value of (18)F-FDG PET/CT volumetric parameters in recurrent epithelial ovarian cancer

OBJECTIVE

Metabolic tumour volume (MTV) and total lesion glycolysis (TLG) from (18)F-FDG PET/CT are emerging prognostic biomarkers in various solid neoplasms. These volumetric parameters and the SUVmax have shown to be useful criteria for disease prognostication in preoperative and post-treatment epithelial ovarian cancer (EOC) patients. The purpose of this study was to evaluate the utility of (18)F-FDG PET/CT measurements to predict survival in patients with recurrent EOC.

MATERIAL AND METHODS

Twenty-six patients with EOC who underwent a total of 31 (18)F-FDG PET/CT studies for suspected recurrence were retrospectively included. SUVmax and volumetric parameters whole-body MTV (wbMTV) and whole-body TLG (wbTLG) with a threshold of 40% and 50% of the SUVmax were obtained. Correlation between PET parameters and progression-free survival (PFS) and the survival analysis of prognostic factors were calculated.

RESULTS

Serous cancer was the most common histological subtype (76.9%). The median PFS was 12.5 months (range 10.7-20.6 months). Volumetric parameters showed moderate inverse correlation with PFS but there was no significant correlation in the case of SUVmax. The correlation was stronger for first recurrences. By Kaplan-Meier analysis and log-rank test, wbMTV 40%, wbMTV 50% and wbTLG 50% correlated with PFS. However, SUVmax and wbTLG 40% were not statistically significant predictors for PFS.

CONCLUSION

Volumetric parameters wbMTV and wbTLG 50% measured by (18)F-FDG PET/CT appear to be useful prognostic predictors of outcome and may provide valuable information to individualize treatment strategies in patients with recurrent EOC.

Benefits of fluorine-18 fludeoxyglucose positron emission tomography in secondary cytoreductive surgery for patients with recurrent epithelial ovarian cancer

OBJECTIVE

To investigate the benefits of fluorine-18 fludeoxyglucose positron emission tomography ((18)F-FDG-PET) in patients undergoing secondary cytoreductive surgery (SCRS) for recurrent epithelial ovarian cancer.

METHODS

Patients were identified, and their clinical information was extracted by review of the gynaecologic oncology database of Peking Union Medical College Hospital. (18)F-FDG-PET scan and analysis were performed by nuclear medicine experts at our hospital.

RESULTS

The PET group and the control group of patients evaluated by conventional imaging methods differed significantly with respect to the proportion of patients who underwent complete SCRS and the number of residual lesions (p = 0.002 and 0.006, respectively). A Cox model showed that longer progression-free survival (PFS) correlated significantly with (18)F-FDG-PET evaluation [relative risk (RR) = 0.432; p = 0.001], sensitivity to platinum-based chemotherapies (RR = 0.604; p = 0.034) and resection completeness (RR = 0.679; p = 0.039). Longer overall survival (OS) correlated significantly with sensitivity to platinum-based chemotherapy (RR = 0.317; p = 0.000) and the CA-125 level after two cycles of chemotherapy (RR = 2.663; p = 0.003). Surgical safety and complications did not significantly differ between the two groups of patients.

CONCLUSION

(18)F-FDG-PET is useful for evaluating patients with recurrent epithelial ovarian carcinoma. Patients who undergo PET-guided SCRS have a greater chance of complete tumour resection and a longer PFS.

ADVANCES IN KNOWLEDGE

SCRS guided by PET results in fewer residual lesions. PET-guided SCRS is safe and can prolong PFS and OS in patients with recurrent ovarian cancer.

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.

Oral gastrografin radiography for the evaluation of the functional impact of peritoneal carcinomatosis: Correlation with clinicopathological findings

This study was conducted to evaluate the functional impact of peritoneal carcinomatosis (PC) on the gastrointestinal system by oral gastrografin radiography (OGR). OGR was performed on 105 patients with PC from abdominal malignancies. The OGR characteristics were analyzed and compared with intraoperative observations. OGR provided real-time dynamic information on the functional impacts of PC. The OGR findings were normal in 9 (8.6%) and abnormal in 96 (91.4%) cases. In terms of frequency, 33 cases (31.4%) exhibited mild intestinal aggregation and flattening of the intestinal mucosa; 29 cases (27.6%) exhibited limited intestinal invasion, marginally stenotic small bowel and mucosal deformities; 26 cases (24.8%) exhibited only mild mesenteric contracture and mild slowing of gastrointestinal peristalsis; 5 cases (4.8%) exhibited obvious mesenteric contracture, ball-like changes, fixed position and disappearance of the intestinal mucosa; 2 cases (1.9%) exhibited complete pyloric obstruction; and 1 case (0.9%) exhibited duodenal obstruction. Gastric PC was associated with a higher percentage of stomach filling defects and small intestinal aggregates compared with PC from other malignancies (P<0.01 for both). In 87 cases, the ORG findings were in accordance with the intraoperative findings (κ=0.726, P<0.001), whereas 17 cases (16.2%) were underestimated and 1 (0.9%) was overestimated by OGR. This study indicated that OGR may be a useful technique for the evaluation of the functional impacts of PC on the gastrointestinal system and may help optimize the selection of patients for treatment.

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.

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.

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

Background

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

Methods

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

Results

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

Conclusion

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

Peritoneal carcinomatosis in patients with ovarian cancer: enhanced CT versus 18F-FDG PET/CT

PURPOSE

The study aimed to evaluate the efficacy of PET/CT in detecting peritoneal carcinomatosis in patients with ovarian cancer and to compare the diagnostic accuracy of FDG PET/CT with that of enhanced abdominal CT.

METHODS

The medical records of 46 consecutive patients with ovarian cancer were reviewed, and the presence of peritoneal tumor on (18)F-FDG PET/CT and enhanced abdominal CT scans was also assessed. Imaging results were compared with the pathologic findings obtained by surgery.

RESULTS

Pathologic results were positive for peritoneal carcinomatosis in 26 patients and negative in 20 patients. PET/CT correctly detected 25 of 26 patients with peritoneal carcinomatosis and enhanced abdominal CT correctly detected 23 of 26 patients. Sensitivity and specificity for the diagnosis of peritoneal carcinomatosis were 96.2% and 90%, respectively, for PET/CT and 88.5% and 65%, respectively, for enhanced abdominal CT. The accuracy of PET/CT was statistically higher than that of enhanced abdominal CT (93.5% vs 78.3%, P = 0.039). Four distinctly abnormal PET/CT findings of single nodular, multiple nodular, diffuse, and mixed FDG uptakes were identified and corresponded to pathologic findings.

CONCLUSIONS

(18)F-FDG PET/CT imaging is efficient in the diagnosis of peritoneal carcinomatosis and its performance is superior to that of enhanced abdominal CT.