Wouter Froyman

Dr. Wouter Froyman


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 July 2021 in International Journal of Gynecological Cancer
Verified
Journal Article
Open access
PDF file
DTDirk Timmerman
Dirk Timmerman
FPFrançois Planchamp
François Planchamp
TBTom Bourne
Tom Bourne
CLChiara Landolfo
Chiara Landolfo
ABAndreas du Bois
Andreas du Bois
CFChristina Fotopoulou
Christina Fotopoulou
The European Society of Gynaecological Oncology (ESGO), the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG), the International Ovarian Tumour Analysis (IOTA) group, and the European Society for Gynaecological Endoscopy (ESGE) jointly developed clinically relevant and evidence-based statements on the pre-operative diagnosis of ovarian tumors, including imaging techniques, biomarkers, and prediction models. ESGO/ISUOG/IOTA/ESGE nominated a multidisciplinary international group, including expert practising clinicians and researchers who have demonstrated leadership and expertise in the pre-operative diagnosis of ovarian tumors and management of patients with ovarian cancer (19 experts across Europe). A patient representative was also included in the group. To ensure that the statements were evidence-based, the current literature was reviewed and critically appraised. Preliminary statements were drafted based on the review of the relevant literature. During a conference call, the whole group discussed each preliminary statement and a first round of voting was carried out. Statements were removed when a consensus among group members was not obtained. The voters had the opportunity to provide comments/suggestions with their votes. The statements were then revised accordingly. Another round of voting was carried out according to the same rules to allow the whole group to evaluate the revised version of the statements. The group achieved consensus on 18 statements. This Consensus Statement presents these ESGO/ISUOG/IOTA/ESGE statements on the pre-operative diagnosis of ovarian tumors and the assessment of carcinomatosis, together with a summary of the evidence supporting each statement.

1 April 2021 in Ultrasound in Obstetrics & Gynecology
Verified
Journal Article
Open access
PDF file
DTDirk Timmerman
Dirk Timmerman
FPFrançois Planchamp
François Planchamp
TBTom Bourne
Tom Bourne
CLChiara Landolfo
Chiara Landolfo
ABAndreas du Bois
Andreas du Bois
CFChristina Fotopoulou
Christina Fotopoulou
The European Society of Gynaecological Oncology (ESGO), the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG), the International Ovarian Tumour Analysis (IOTA) group and the European Society for Gynaecological Endoscopy (ESGE) jointly developed clinically relevant and evidence‐based statements on the preoperative diagnosis of ovarian tumors, including imaging techniques, biomarkers and prediction models.ESGO/ISUOG/IOTA/ESGE nominated a multidisciplinary international group, including expert practising clinicians and researchers who have demonstrated leadership and expertise in the preoperative diagnosis of ovarian tumors and management of patients with ovarian cancer (19 experts across Europe). A patient representative was also included in the group. To ensure that the statements were evidence‐based, the current literature was reviewed and critically appraised.Preliminary statements were drafted based on the review of the relevant literature. During a conference call, the whole group discussed each preliminary statement and a first round of voting was carried out. Statements were removed when consensus among group members was not obtained. The voters had the opportunity to provide comments/suggestions with their votes. The statements were then revised accordingly. Another round of voting was carried out according to the same rules to allow the whole group to evaluate the revised version of the statements. The group achieved consensus on 18 statements.This Consensus Statement presents these ESGO/ISUOG/IOTA/ESGE statements on the preoperative diagnosis of ovarian tumors and the assessment of carcinomatosis, together with a summary of the evidence supporting each statement.

30 July 2020 in BMJ
Verified
Journal Article
Open access
PDF file
BCBen Van Calster
Ben Van Calster
LVLil Valentin
Lil Valentin
WFWouter Froyman
Wouter Froyman
CLChiara Landolfo
Chiara Landolfo
JCJolien Ceusters
Jolien Ceusters
DTDirk Timmerman
Dirk Timmerman
Objective To evaluate the performance of diagnostic prediction models for ovarian malignancy in all patients with an ovarian mass managed surgically or conservatively. Design Multicentre cohort study. Setting 36 oncology referral centres (tertiary centres with a specific gynaecological oncology unit) or other types of centre. Participants Consecutive adult patients presenting with an adnexal mass between January 2012 and March 2015 and managed by surgery or follow-up. Main outcome measures Overall and centre specific discrimination, calibration, and clinical utility of six prediction models for ovarian malignancy (risk of malignancy index (RMI), logistic regression model 2 (LR2), simple rules, simple rules risk model (SRRisk), assessment of different neoplasias in the adnexa (ADNEX) with or without CA125). ADNEX allows the risk of malignancy to be subdivided into risks of a borderline, stage I primary, stage II-IV primary, or secondary metastatic malignancy. The outcome was based on histology if patients underwent surgery, or on results of clinical and ultrasound follow-up at 12 (±2) months. Multiple imputation was used when outcome based on follow-up was uncertain. Results The primary analysis included 17 centres that met strict quality criteria for surgical and follow-up data (5717 of all 8519 patients). 812 patients (14%) had a mass that was already in follow-up at study recruitment, therefore 4905 patients were included in the statistical analysis. The outcome was benign in 3441 (70%) patients and malignant in 978 (20%). Uncertain outcomes (486, 10%) were most often explained by limited follow-up information. The overall area under the receiver operating characteristic curve was highest for ADNEX with CA125 (0.94, 95% confidence interval 0.92 to 0.96), ADNEX without CA125 (0.94, 0.91 to 0.95) and SRRisk (0.94, 0.91 to 0.95), and lowest for RMI (0.89, 0.85 to 0.92). Calibration varied among centres for all models, however the ADNEX models and SRRisk were the best calibrated. Calibration of the estimated risks for the tumour subtypes was good for ADNEX irrespective of whether or not CA125 was included as a predictor. Overall clinical utility (net benefit) was highest for the ADNEX models and SRRisk, and lowest for RMI. For patients who received at least one follow-up scan (n=1958), overall area under the receiver operating characteristic curve ranged from 0.76 (95% confidence interval 0.66 to 0.84) for RMI to 0.89 (0.81 to 0.94) for ADNEX with CA125. Conclusions Our study found the ADNEX models and SRRisk are the best models to distinguish between benign and malignant masses in all patients presenting with an adnexal mass, including those managed conservatively. Trial registration ClinicalTrials.gov NCT01698632.

12 January 2023 in Ultrasound in Obstetrics & Gynecology
Verified
Journal Article
Open access
CLC. Landolfo
C. Landolfo
TBT. Bourne
T. Bourne
WFWouter Froyman
Wouter Froyman
BCB. Van Calster
B. Van Calster
JCJ. Ceusters
J. Ceusters
LVLil Valentin
Lil Valentin
Objective: Previous work has suggested that the ultrasound‐based benign simple descriptors (BDs) can reliably exclude malignancy in a large proportion of women presenting with an adnexal mass. This study aimed to validate a modified version of the BDs and to validate a two‐step strategy to estimate the risk of malignancy, in which the modified BDs are followed by the Assessment of Different NEoplasias in the adneXa (ADNEX) model if modified BDs do not apply.Methods: This was a retrospective analysis using data from the 2‐year interim analysis of the International Ovarian Tumor Analysis (IOTA) Phase‐5 study, in which consecutive patients with at least one adnexal mass were recruited irrespective of subsequent management (conservative or surgery). The main outcome was classification of tumors as benign or malignant, based on histology or on clinical and ultrasound information during 1 year of follow‐up. Multiple imputation was used when outcome based on follow‐up was uncertain according to predefined criteria.Results: A total of 8519 patients were recruited at 36 centers between 2012 and 2015. We excluded patients who were already in follow‐up at recruitment and all patients from 19 centers that did not fulfil our criteria for good‐quality surgical and follow‐up data, leaving 4905 patients across 17 centers for statistical analysis. Overall, 3441 (70%) tumors were benign, 978 (20%) malignant and 486 (10%) uncertain. The modified BDs were applicable in 1798/4905 (37%) tumors, of which 1786 (99.3%) were benign. The two‐step strategy based on ADNEX without CA125 had an area under the receiver‐operating‐characteristics curve (AUC) of 0.94 (95% CI, 0.92–0.96). The risk of malignancy was slightly underestimated, but calibration varied between centers. A sensitivity analysis in which we expanded the definition of uncertain outcome resulted in 1419 (29%) tumors with uncertain outcome and an AUC of the two‐step strategy without CA125 of 0.93 (95% CI, 0.91–0.95).Conclusion: A large proportion of adnexal masses can be classified as benign by the modified BDs. For the remaining masses, the ADNEX model can be used to estimate the risk of malignancy. This two‐step strategy is convenient for clinical use. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

1 February 2023 in JAMA Oncology
Verified
Journal Article
Open access
PDF file
STStefan Timmerman
Stefan Timmerman
LVLil Valentin
Lil Valentin
JCJolien Ceusters
Jolien Ceusters
ATAntonia C. Testa
Antonia C. Testa
CLChiara Landolfo
Chiara Landolfo
WFWouter Froyman
Wouter Froyman
Ovarian cancer is the eighth most common cancer worldwide in women and is the most lethal gynecologic malignancy.1 Because patients with ovarian cancer have a better prognosis when treated in tertiary oncology centers than in other centers, correct preoperative diagnosis of adnexal masses should result in optimal management.2-6

12 February 2024 in Acta Obstetricia et Gynecologica Scandinavica
Verified
Journal Article
Open access
STStefan Timmerman
Stefan Timmerman
LSLauren Stubbe
Lauren Stubbe
TBThierry Van Den Bosch
Thierry Van Den Bosch
DSDominique Van Schoubroeck
Dominique Van Schoubroeck
TTTina Tellum
Tina Tellum
WFWouter Froyman
Wouter Froyman
Introduction: Accessory cavitated uterine malformation (ACUM) is a relatively recent term used to describe a noncommunicating, accessory uterine cavity. ACUM have been published under different terms ranging from juvenile cystic adenomyosis to “uterus‐like mass”. The objective of this study was to systematically identify all cases of ACUM and definitions described in the literature, regardless of label, and identify morphological, epidemiological, and clinical characteristics as well as management, while also highlighting knowledge gaps.Material and methods: A systematic literature search of three databases was performed, reviewing all records of cystic myometrial lesions. Cases that fitted common definitions for ACUM were included and clinical and imaging characteristics were documented in detail. This work was registered to PROSPERO and reporting followed PRISMA guidelines for scoping reviews.Results: A total of 53 articles were included, comprising 115 cases that met the minimal criteria for ACUM. The median age at onset of symptoms was 17 years, presenting with dysmenorrhea soon after menarche. A total of 19 women were parous. On ultrasound, ACUM appears as unilocular myometrial cysts, usually with ground‐glass content. Hemorrhagic content is also observed on magnetic resonance imaging (MRI), with high signal intensity on both T2 and T1‐weighted images. Ninety‐five (83%) cases were managed surgically, with a trend towards primary nonsurgical options. Although no adverse outcomes were reported, long‐term follow‐up on subsequent fertility and pregnancy was rare.Conclusions: Despite its increasing recognition as a clinical entity, ACUM often remains underdiagnosed as it shares similarities with other myometrial masses. We propose a unified terminology and definition for ACUM based on the data in this review. ACUM presents as a cavitated lesion, surrounded by a myometrial mantle, in continuity with the anterolateral uterine wall and located beneath the insertion of the round ligament and the interstitial portion of the fallopian tube. In contrast to other uterine abnormalities, a normal uterine cavity is visualized. Future studies are needed, using a clear definition for ACUM, and prospectively investigating management strategies, including long‐term follow‐up of patient‐reported symptoms, fertility, and pregnancy outcomes.