Prediction of Surgical Outcome in Advanced Ovarian Cancer by Imaging and Laparoscopy: A Narrative Review

Computed tomography-based prediction of interval cytoreduction in advanced ovarian cancer

OBJECTIVE

Our retrospective study aimed to investigate the role of computed tomography (CT) using both the tomographic Fagotti index and the Sugarbaker peritoneal cancer index (PCI) in predicting the feasibility of optimal interval debulking surgery in epithelial ovarian cancer.

METHODS

Patients with advanced ovarian cancer treated in our institution who were eligible for interval debulking surgery were identified and included in the study. A retrospective image collection was operated, and CT scan evaluations were conducted by 2 independent radiologists to establish both scores (Fagotti index and Sugarbaker PCI). The workflow included a third radiologist who resolved discrepancies. The receiver operating characteristics curve followed by the Youden J statistic was calculated to determine cutoff points that best differentiated complete/optimal versus suboptimal cytoreduction. The Fagotti index and Sugarbaker PCI cutoffs' accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were calculated and represented as 95% CIs.

RESULTS

A total of 60 consecutive patients who had complete information in their charts with evaluable images and complete information about surgery were evaluated; of these, 35 had a complete/optimal interval debulking surgery. The receiver operating characteristic curve of the Fagotti index scoring system showed that a cutoff of ≥3 can identify 100% of inoperable patients. However, 29% of patients were falsely labeled as inoperable. A cutoff point of ≥5 avoids 88% of unnecessary laparotomies, reducing the rate of false inoperable designation from 29% to 17%. A Sugarbaker PCI of ≥8 predicts the risk of unnecessary laparotomies in 68%, with 26% falsely labeled as inoperable. The score of ≥7 is most effective in avoiding unnecessary surgeries (80%), but the chance of false positives increases from 26% to 32%.

CONCLUSION

CT-based scoring systems used in the present work can help determine which patients with advanced ovarian cancer are suitable for interval debulking surgery with high precision. Future studies are needed to enhance accuracy, thereby amplifying the radiologists' competency in using a systematic CT-based scoring system.

Prediction of non-resectability in tubo-ovarian cancer patients using Peritoneal Cancer Index - A prospective multicentric study using imaging (ISAAC study)

BACKGROUND

The aim was to evaluate the performance of the Peritoneal Cancer Index (PCI) using imaging (ultrasound, contrast-enhanced computed tomography (CT), and whole-body diffusion-weighted magnetic resonance imaging (WB-DWI/MRI) in assessing peritoneal carcinomatosis and predicting non-resectability in tubo-ovarian carcinoma patients.

METHODS

This was a prospective multicenter observational study. We considered all patients with suspected primary ovarian/tubal/peritoneal cancer who underwent preoperative ultrasound, CT, and WB-DWI/MRI (if available). The optimal cut off value for assessing the performance of the methods in predicting non-resectability was identified at the point at which the sensitivity and specificity were most similar. The reference standard to predict non-resectability was surgical outcome in terms of residual disease >1 cm or surgery not feasible. Agreement between imaging methods and surgical exploration in assessing sites included in the PCI score was evaluated using the Intraclass Correlation Coefficient (ICC).

RESULTS

242 patients were included from January 2020 until November 2022. The optimal PCI cut-off for predicting non-resectability for surgical exploration was >12, which achieved the best AUC of 0.87, followed by ultrasound with a cut-off of >10 and AUC of 0.81, WB-DWI/MRI with a cut-off of >12 and AUC of 0.81, and CT with a cut-off of >11 and AUC of 0.74. Using ICC, ultrasound had very high agreement (0.94) with surgical PCI, while CT and WB-DWI/MRI had high agreement (0.86 and 0.87, respectively).

CONCLUSION

Ultrasound performed by an expert operator had the best agreement with surgical findings compared to WB-DWI/MRI and CT in assessing radiological PCI. In predicting non-resectability, ultrasound was non-inferior to CT, while its non-inferiority to WB-DWI/MRI was not demonstrated.

Comparison of 68Ga-FAPI-04 and 18F-FDG PET/CT in diagnosing ovarian cancer

PURPOSE

This study assesses the diagnostic performance of 68Ga-FAPI-04 PET/CT compared to 18F-FDG PET/CT in primary, recurrent, and metastatic ovarian cancer.

METHODS

Seventy-nine ovarian cancer patients who performed 68Ga-FAPI-04 and 18F-FDG PET/CT were recruited. The target-to-background ratio (TBR), maximum standardized uptake value (SUVmax), the number of positive lesions, visual assessment, the peritoneal cancer index (PCI) score, staging/restaging, and treatment strategies were compared from the corresponding PET/CT. Additionally, we analyzed and contrasted the diagnostic efficacy in both scans.

RESULTS

Among all patients, 6 were assessed for initial assessment and 73 for recurrence and metastasis detection. For all lesions, 68Ga-FAPI-04 PET/CT demonstrated greater TBR than 18F-FDG PET/CT. 68Ga-FAPI-04 PET/CT demonstrated higher sensitivity for peritoneal metastases including patient-based and lesion-based analysis (95.00% vs. 83.33%, P = 0.065; 90.16% vs. 60.66%, P < 0.001) and a higher PCI score [median PCI: 6 (4, 12) vs. 4 (2, 8), P < 0.001]. According to the visual assessment, 68Ga-FAPI-04 PET revealed larger extent metastases in 55.93% (33/59) of the patients with peritoneal metastases. 68Ga-FAPI-04 was upstaged in 7 patients (8.86%, 7/79) and discrepancies in both scans caused treatment strategies to change in 11 patients (13.92%, 11/79).

CONCLUSION

68Ga-FAPI-04 PET/CT outperforms 18F-FDG PET/CT in identifying metastases and can be a potential supplement for managing ovarian cancer patients.

Predicting Complete Cytoreduction with Preoperative [18F]FDG PET/CT in Patients with Ovarian Cancer: A Systematic Review and Meta-Analysis

The cornerstone of ovarian cancer treatment is complete surgical cytoreduction. The gold-standard option in the absence of extra-abdominal metastases and intra-abdominal inoperable circumstances is primary cytoreductive surgery (CRS). However, achieving complete cytoreduction is challenging, and only possible in a selected patient population. Preoperative imaging modalities such as [18F]FDG PET/CT could be useful in patient selection for cytoreductive surgery. In our systematic review and meta-analysis, we aimed to evaluate the role of preoperative [18F]FDG PET/CT in predicting complete cytoreduction in primary and secondary debulking surgeries. Publications were pooled from two databases (PubMed, Mendeley) with predefined keywords "(ovarian cancer) AND (FDG OR PET) AND (cytoreductive surgery)". The quality of the included studies was assessed with the Prediction model Risk Of Bias Assessment Tool (PROBAST). During statistical analysis, MetaDiSc 1.4 software and the DerSimonian-Laird method (random effects models) were used. Primary and secondary cytoreductive surgeries were evaluated. Pooled sensitivities, specificities, positive predictive values (PPVs), and negative predictive values (NPVs) were calculated and statistically analyzed. Results were presented in forest plot diagrams and summary receiver operating characteristic (SROC) curves. Overall, eight publications were included in our meta-analysis. Four publications presented results of primary, three presented results of secondary cytoreductions, and two presented data related to both primary and secondary surgery. Pooled sensitivities, specificities, and positive and negative predictive values were the following: in the case of primary surgeries: 0.65 (95% CI 0.60-0.71), 0.73 (95% CI 0.66-0.80), 0.82 (95% CI 0.77-0.87), 0.52 (95% CI 0.46-0.59); and in the case of secondary surgeries: 0.91 (95% CI 0.84-0.95), 0.48 (95% CI 0.30-0.67), 0.88 (95% CI 0.81-0.93), 0.56 (95% CI 0.35-0.75), respectively. The PPVs of [18F]FDG PET/CT proved to be higher in cases of secondary debulking surgeries; therefore, it can be a valuable predictor of complete successful secondary cytoreduction.

Ovarian Cancer Staging-How CT Scan Descriptions Differ from Surgical Findings

Ovarian cancer is one of the most common causes of cancer death in women worldwide. Most often, it is detected in an advanced stage due to its insidious onset and lack of symptoms in stages I and II. That is why imaging diagnostics is so important. Therefore, we assessed the consistency of the image seen on CT with the actual image assessed during surgery. Objectives: The aim of this study is to compare preoperative evaluation based on CT reports with those obtained during ovarian cancer surgery to determine whether CT is helpful in assessing the possibility of optimal or complete cytoreduction. Methods: This retrospective study included patients diagnosed with ovarian cancer who underwent diagnostic laparoscopy or laparotomy with cytoreduction. We compared ovarian cancer lesions described by radiologists on CT scans to those described during laparoscopy or laparotomy; the Wilcoxon signed-rank test for paired observations was used to compare the variables. Results: We observed that the morphology of the tumor, mesenteric infiltration, and the assessment of the involvement of the abdominal, para-aortic, and iliac lymph nodes may differ in CT examination and during surgery. Conclusions: The site of the tumor exit on a CT scan does not always reflect the original site seen during surgery.

A modified diffusion-weighted magnetic resonance imaging-based model from the radiologist's perspective: improved performance in determining the surgical resectability of advanced high-grade serous ovarian cancer

BACKGROUND

Complete resection of all visible lesions during primary debulking surgery is associated with the most favorable prognosis in patients with advanced high-grade serous ovarian cancer. An accurate preoperative assessment of resectability is pivotal for tailored management.

OBJECTIVE

This study aimed to assess the potential value of a modified model that integrates the original 8 radiologic criteria of the Memorial Sloan Kettering Cancer Center model with imaging features of the subcapsular or diaphragm and mesenteric lesions depicted on diffusion-weighted magnetic resonance imaging and growth patterns of all lesions for predicting the resectability of advanced high-grade serous ovarian cancer.

STUDY DESIGN

This study included 184 patients with high-grade serous ovarian cancer who underwent preoperative diffusion-weighted magnetic resonance imaging between December 2018 and May 2023 at 2 medical centers. The patient cohort was divided into 3 subsets, namely a study cohort (n=100), an internal validation cohort (n=46), and an external validation cohort (n=38). Preoperative radiologic evaluations were independently conducted by 2 radiologists using both the Memorial Sloan Kettering Cancer Center model and the modified diffusion-weighted magnetic resonance imaging-based model. The morphologic characteristics of the ovarian tumors depicted on magnetic resonance imaging were assessed as either mass-like or infiltrative, and transcriptomic analysis of the primary tumor samples was performed. Univariate and multivariate statistical analyses were performed.

RESULTS

In the study cohort, both the scores derived using the Memorial Sloan Kettering Cancer Center (intraclass correlation coefficients of 0.980 and 0.959, respectively; both P<.001) and modified diffusion-weighted magnetic resonance imaging-based models (intraclass correlation coefficients of 0.962 and 0.940, respectively; both P<.001) demonstrated excellent intra- and interobserver agreement. The Memorial Sloan Kettering Cancer Center model (odds ratio, 1.825; 95% confidence interval, 1.390-2.395; P<.001) and the modified diffusion-weighted magnetic resonance imaging-based model (odds ratio, 1.776; 95% confidence interval, 1.410-2.238; P<.001) independently predicted surgical resectability. The modified diffusion-weighted magnetic resonance imaging-based model demonstrated improved predictive performance with an area under the curve of 0.867 in the study cohort and 0.806 and 0.913 in the internal and external validation cohorts, respectively. Using the modified diffusion-weighted magnetic resonance imaging-based model, patients with scores of 0 to 2, 3 to 4, 5 to 6, 7 to 10, and ≥11 achieved complete tumor debulking rates of 90.3%, 66.7%, 53.3%, 11.8%, and 0%, respectively. Most patients with incomplete tumor debulking had infiltrative tumors, and both the Memorial Sloan Kettering Cancer Center and the modified diffusion-weighted magnetic resonance imaging-based models yielded higher scores. The molecular differences between the 2 morphologic subtypes were identified.

CONCLUSION

When compared with the Memorial Sloan Kettering Cancer Center model, the modified diffusion-weighted magnetic resonance imaging-based model demonstrated enhanced accuracy in the preoperative prediction of resectability for advanced high-grade serous ovarian cancer. Patients with scores of 0 to 6 were eligible for primary debulking surgery.

Diagnostic accuracy and clinical value of [68Ga]Ga-FAPI-46 PET/CT for staging patients with ovarian cancer: study protocol for a prospective clinical trial

BACKGROUND

[18F]Fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) is recommended during diagnostic work-up for ovarian cancer; however, [18F]FDG PET has several inherent limitations. The novel oncologic PET-tracer fibroblast activation protein inhibitor (FAPI) has demonstrated promising results in multiple cancer types, including ovarian cancer, and could overcome the limitations of [18F]FDG PET; however, high-quality clinical studies are lacking. The primary objective of the present study is to compare the diagnostic accuracy of [68Ga]Ga-FAPI-46 PET/CT and [18F]FDG PET/CT in ovarian cancer patients and to investigate how this potential difference impacts staging and patient management.

METHODS AND DESIGN

Fifty consecutive ovarian cancer patients will be recruited from Aalborg University Hospital, Denmark. This study will be a single-center, prospective, exploratory clinical trial that adheres to the standards for reporting diagnostic accuracy studies (STARD). This study will be conducted under continuous Good Clinical Practice monitoring. The eligibility criteria for patients are as follows: (1) biopsy verified newly diagnosed ovarian cancer or a high risk of ovarian cancer and referred for primary staging with [18F]FDG PET/CT; and (2) resectable disease, i.e., candidate for primary debulking surgery or neoadjuvant chemotherapy followed by interval debulking surgery. All recruited study subjects will undergo [68Ga]Ga-FAPI-46 PET/CT at primary staging, before primary debulking surgery or neoadjuvant chemotherapy (Group A + B), in addition to conventional imaging (including [18F]FDG PET/CT). Study subjects in Group B will undergo an additional [68Ga]Ga-FAPI-46 PET/CT following neoadjuvant chemotherapy prior to interval debulking surgery. The results of the study-related [68Ga]Ga-FAPI-46 PET/CTs will be blinded, and treatment allocation will be based on common clinical practice in accordance with current guidelines. The histopathology of surgical specimens will serve as a reference standard. A recruitment period of 2 years is estimated; the trial is currently recruiting.

DISCUSSION

To our knowledge, this trial represents the largest, most extensive, and most meticulous prospective FAPI PET study conducted in patients with ovarian cancer thus far. This study aims to obtain a reliable estimation of the diagnostic accuracy of [68Ga]Ga-FAPI-46 PET/CT, shed light on the clinical importance of [68Ga]Ga-FAPI-46 PET/CT, and examine the potential applicability of [68Ga]Ga-FAPI-46 PET/CT for evaluating chemotherapy response.

TRIAL REGISTRATION

clinicaltrials.gov: NCT05903807, 2nd June 2023; and euclinicaltrials.eu EU CT Number: 2023-505938-98-00, authorized 11th September 2023.

Patient satisfaction with ultrasound, whole-body CT and whole-body diffusion-weighted MRI for pre-operative ovarian cancer staging: a multicenter prospective cross-sectional survey

BACKGROUND

In addition to the diagnostic accuracy of imaging methods, patient-reported satisfaction with imaging methods is important.

OBJECTIVE

To report a secondary outcome of the prospective international multicenter Imaging Study in Advanced ovArian Cancer (ISAAC Study), detailing patients' experience with abdomino-pelvic ultrasound, whole-body contrast-enhanced computed tomography (CT), and whole-body diffusion-weighted magnetic resonance imaging (WB-DWI/MRI) for pre-operative ovarian cancer work-up.

METHODS

In total, 144 patients with suspected ovarian cancer at four institutions in two countries (Italy, Czech Republic) underwent ultrasound, CT, and WB-DWI/MRI for pre-operative work-up between January 2020 and November 2022. After having undergone all three examinations, the patients filled in a questionnaire evaluating their overall experience and experience in five domains: preparation before the examination, duration of examination, noise during the procedure, radiation load of CT, and surrounding space. Pain perception, examination-related patient-perceived unexpected, unpleasant, or dangerous events ('adverse events'), and preferred method were also noted.

RESULTS

Ultrasound was the preferred method by 49% (70/144) of responders, followed by CT (38%, 55/144), and WB-DWI/MRI (13%, 19/144) (p<0.001). The poorest experience in all domains was reported for WB-DWI/MRI, which was also associated with the largest number of patients who reported adverse events (eg, dyspnea). Patients reported higher levels of pain during the ultrasound examination than during CT and WB-DWI/MRI (p<0.001): 78% (112/144) reported no pain or mild pain, 19% (27/144) moderate pain, and 3% (5/144) reported severe pain (pain score >7 of 10) during the ultrasound examination. We did not identify any factors related to patients' preferred method.

CONCLUSION

Ultrasound was the imaging method preferred by most patients despite being associated with more pain during the examination in comparison with CT and WB-DWI/MRI.

TRIAL REGISTRATION NUMBER

NCT03808792.

First external validity study of the Fagotti score in ovarian cancer

Epithelial ovarian cancer is mostly discovered at the stage of peritoneal carcinosis. Complete cytoreductive surgery improves overall survival. The Fagotti score is a predictive score of resectability based on peritoneal laparoscopic exploratory. Our aim was to study the inter-observer concordance in an external validation of the Fagotti score. An observational, prospective, multicenter study was conducted using the Francogyn research network. The primary outcome was inter-observer concordance of the Fagotti score. 15 patients in which an ovarian mass was discovered were included. For each patient, the first exploratory laparoscopy before any treatment/chemotherapy was recorded. This bank of 15 videos was subject to blind review accompanied by a Fagotti score rating by 11 gynecological surgeons specializing in oncology. A total of 165 blind reviews were performed. Inter-observer concordance was very good for the Fagotti score with an intraclass correlation coefficient (ICC) of 0.83 [95% CI 0.71; 0.93]. Inter-observer concordance for the adjusted Fagotti score, which accounts for unexplorable areas with extensive carcinomatosis, resulted in an ICC of 0.64 [95% CI 0.46; 0.82]. According to the reviewers, the three least explorable parameters were mesentery involvement, stomach infiltration and liver damage. The ICC of the explorable Fagotti score, i.e. score with deletion of the parameters most often unexplored by laparoscopy, was 0.86 [0.75-0.94]. This study confirms the reproducibility of the Fagotti score during first assessment laparoscopies in cases of advanced ovarian cancer. The explorable Fagotti score has an equivalent or better inter-observer concordance than the Fagotti score.

Staging by imaging in gynecologic cancer and the role of ultrasound: an update of European joint consensus statements

In recent years the role of diagnostic imaging by pelvic ultrasound in the diagnosis and staging of gynecological cancers has been growing exponentially. Evidence from recent prospective multicenter studies has demonstrated high accuracy for pre-operative locoregional ultrasound staging in gynecological cancers. Therefore, in many leading gynecologic oncology units, ultrasound is implemented next to pelvic MRI as the first-line imaging modality for gynecological cancer. The work herein is a consensus statement on the role of pre-operative imaging by ultrasound and other imaging modalities in gynecological cancer, following European Society guidelines.

Neglected Anatomical Areas in Ovarian Cancer: Significance for Optimal Debulking Surgery

Ovarian cancer (OC), the most lethal gynecological malignancy, usually presents in advanced stages. Characterized by peritoneal and lymphatic dissemination, OC necessitates a complex surgical approach usually involving the upper abdomen with the aim of achieving optimal cytoreduction without visible macroscopic disease (R0). Failures in optimal cytoreduction, essential for prognosis, often stem from overlooking anatomical neglected sites that harbor residual tumor. Concealed OC metastases may be found in anatomical locations such as the omental bursa; Morison's pouch; the base of the round ligament and hepatic bridge; the splenic hilum; and suprarenal, retrocrural, cardiophrenic and inguinal lymph nodes. Hence, mastery of anatomy is crucial, given the necessity for maneuvers like liver mobilization, diaphragmatic peritonectomy and splenectomy, as well as dissection of suprarenal, celiac, and cardiophrenic lymph nodes in most cases. This article provides a meticulous anatomical description of neglected anatomical areas during OC surgery and describes surgical steps essential for the dissection of these "neglected" areas. This knowledge should equip clinicians with the tools needed for safe and complete cytoreduction in OC patients.

Survival Dynamics in Advanced Ovarian Cancer: R2 Resection Versus No-Surgery Paths Explored

BACKGROUND

Cytoreductive surgery is critical for optimal tumor clearance in advanced epithelial ovarian cancer (EOC). Despite best efforts, some patients may experience R2 (>1 cm) resection, while others may not undergo surgery at all. We aimed to compare outcomes between advanced EOC patients undergoing R2 resection and those who had no surgery.

METHODS

Retrospective data from 51 patients with R2 resection were compared to 122 patients with no surgery between January 2015 and December 2019 at a UK tertiary referral centre. Progression-free survival (PFS) and overall survival (OS) were the study endpoints. Principal Component Analysis and Term Frequency - Inverse Document Frequency scores were utilized for data discrimination and prediction of R>2 cm from computed tomography pre-operative reports, respectively.

RESULTS

No statistical significance was observed, except for age (73 vs 67 years in the no- surgery vs R2 group, P: .001). Principal Components explained 34% of data variances. Reasons for no surgery included age, co-morbidities, patient preference, refractory disease, patient deterioration or disease progression, and absence of measurable intra- abdominal disease). The median PFS and OS were 12 and 14 months for no-surgery, vs 14 and 26 months for R2 (P: .138 and P: .001, respectively). Serous histology and performance status independently predicted PFS in both no-surgery and R2 cohorts. In the no-surgery cohort, serous histology independently predicted OS, while in the R2 cohorts, both serous histology and adjuvant chemotherapy were independent prognostic features for OS. The bi-grams "abdominopelvic ascites" and "solid omental" were amongst those best discriminating between R>2 cm and R1-2 cm.

CONCLUSIONS

R2 resection and no-surgery cohorts displayed unfavourable prognosis with a notable degree of uniformity. When cytoreduction results in suboptimal results, the survival benefit may still be higher compared to those who underwent no surgery.

Ultrasound for assessing tumor spread in ovarian cancer. A systematic review of the literature and meta-analysis

In this review, we aimed to assess the diagnostic performance of ultrasound for assessing the tumor spread in the abdomen in women with ovarian cancer. A search for studies evaluating the role of ultrasound for assessing intrabdominal tumor spread in women with ovarian cancer compared to surgery from January 2011 to March 2023 was performed in PubMed/MEDLINE, Web of Science, and Scopus databases. The Quality Assessment of Diagnostic Accuracy Studies 2 evaluated the quality of the studies (QUADAS-2). All analyses were performed using MIDAS and METANDI commands in STATA 12.0 software. We identified 1552 citations. After exclusions, five studies comprising 822 women were included. Quality of studies were considered as good, except for patient selection as all studies were considered as having high risk of bias. The pooled sensitivity and specificity could be calculated for three anatomical areas (recto-sigma, major omentum and root of mesentery) and the presence of ascites. The pooled sensitivity and specificity for detecting disease in the recto-sigma, major omentum and root of mesentery were 0.83 and 0.95, 0.87 and 0.87, and 0.29 and 0.99, respectively. The pooled sensitivity and specificity for detecting ascites was 0.95 and 0.91, respectively. There is evidence that ultrasound offers good diagnostic performance for evaluating the intra-abdominal extent of disease in women with suspected ovarian cancer.

Imaging of Peritoneal Carcinomatosis in Advanced Ovarian Cancer: CT, MRI, Radiomic Features and Resectability Criteria

PC represents the most striking picture of the loco-regional spread of ovarian cancer, configuring stage III. In the last few years, many papers have evaluated the role of imaging and therapeutic management in patients with ovarian cancer and PC. This paper summed up the literature on traditional approaches to the imaging of peritoneal carcinomatosis in advanced ovarian cancer, presenting classification systems, most frequent patterns, routes of spread and sites that are difficult to identify. The role of imaging in diagnosis was investigated, with particular attention to the reported sensitivity and specificity data-computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography-CT (PET-CT)-and to the peritoneal cancer index (PCI). In addition, we explored the therapeutic possibilities and radiomics applications that can impact management of patients with ovarian cancer. Careful staging is mandatory, and patient selection is one of the most important factors influencing complete cytoreduction (CCR) outcome: an accurate pre-operative imaging may allow selection of patients that may benefit most from primary cytoreductive surgery.