Routine Shallow-coverage Whole Genome Sequencing Testing of Liquid-based Cervical Smears for the Early Diagnosis of Ovarian Cancer (SHALLOW ROUTE)

September 11, 2026 updated by: Institut Claudius Regaud

High-grade serous ovarian carcinoma (HGSOC) is the deadliest gynaecological tumour. The 5-year overall survival rate for advanced-stage disease is less than 30 per cent, due to diagnosis at an advanced stage.

There is currently no validated screening test for ovarian cancer. According to the literature, the current hypothesis is that HGSOCs develop primarily from the distal part of the fallopian tube, which is anatomically close to the lower genital tract. Tumour cells have even been observed in cervical smears.

Studies suggest that early diagnosis of HGSOC is possible non-invasively by detecting pathogenic variants of the TP53 gene in DNA extracted from cervical smears.

Studies suggest that early diagnosis of HGSOC is possible using non-invasive methods by detecting pathogenic variants in the TP53 gene in deoxyribonucleic acid (DNA) extracted from cervical smears.

In 2023, whole-genome sequencing (WGS) of DNA extracted from cervical smears to detect genomic instability successfully identified the presence of high-grade serous ovarian cancer up to nine years before diagnosis. This study demonstrates the feasibility of early diagnosis of ovarian cancer using genomic instability analysis via Shallow-coverage whole-genome sequencing (sWGS) on DNA obtained from cervical smears.

This study aim to confirm the feasibility of diagnosing high-grade serous ovarian carcinoma by analysing genomic instability via sWGS on DNA extracted from liquid-based cervical smears, using a homogeneous series of samples from patients treated at the Toulouse University Cancer Institute-Oncopole (IUCT-Oncopole).

Study Overview

Detailed Description

  1. Cohort constitution Patients treated at the Toulouse University Cancer Institute-Oncopole (IUCT-Oncopole) for high-grade serous ovarian cancer (HGSOC) at any stage, and for whom an initial surgical procedure (diagnostic or cytoreductive) is planned as part of their treatment pathway, may be included. For these patients, tumour and healthy tissue samples are systematically collected (taken as part of the ovarian cancer care pathway) and a liquid-based cervical smear is performed (carried out to screen for concomitant cervical cancer).

    The liquid-based cytology technique, which has replaced the cervical smear used in retrospective studies, reduces the number of unsatisfactory samples, enables the detection of human papillomavirus (HPV) and allows molecular and cytological tests to be carried out using a single sample. Any abnormalities found in this sample may be considered specific to an ovarian origin, given the exclusion of patients with other cancers of the reproductive tract (in particular TP53-mutated endometrial carcinomas). The samples will be forwarded to the pathology department via the usual procedure.

  2. Analysis of samples Tumour and healthy tissue samples are fixed in formalin and then embedded in paraffin. The diagnosis is made on the tumour sample using standard staining and immunohistochemical analysis. An assessment of the quantity of tumour material (cell density and tumour area) is carried out. Following extraction, the DNA is quantified and characterised by the molecular biology platform using the an assay kit from Thermo Fisher Scientific. Shallow-coverage whole-genome sequencing (sWGS) is routinely performed on the tumour sample with 2X coverage on platform to assess homologous recombination deficiency (HRD) status, thereby determining eligibility for PARP enzyme inhibitors prescription.

    The same procedure is used for healthy tissue as part of the study. The liquid-based cervical sample is processed according to the routine protocol as part of cervical cancer screening. The residual sample is centrifuged and DNA is extracted from the pellet to perform the sWGS technique, which is comparable to that carried out on tumour tissue.

    The residual samples - the block of healthy tissue, DNA extracted from the tumour tissue and cervical fluid - are stored.

  3. Implementation and analysis using bioinformatics tools The sequences generated will be aligned to the GRCh38 reference genome using the bwa mem software, and duplicates will be removed using picard-tools. The open-source CPA8 pipelines and the adaptation of the genomic index (GI) for HGSOC published by the ONCOSARC team will be implemented in the available local environment. The comparative analysis will be based on sampling sites and patient characteristics (e.g. FIGO (International Federation of Gynaecology and Obstetrics) stage).

The analysis will be carried out in collaboration with the bioinformatics team in the pathology department.

Study Type

Observational

Enrollment (Estimated)

50

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Women with high grade serous ovarian carcinoma treated at Toulouse university of cancer-Oncopole.

Description

Inclusion Criteria:

Patients :

  • With high-grade serous ovarian carcinoma treated at the IUCT-O
  • For whom initial surgery (diagnostic or cytoreductive) is planned

Exclusion Criteria:

Patients with :

  • Concurrent endometrial or cervical cancer
  • History of cancer within the last two years
  • History of gynaecological cancer
  • History of salpingectomy, hysterectomy or trachelectomy (removal of the cervix)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Proportion of patients with a positive CPA test on tumour and cervical samples measure
Time Frame: For each patient at baseline

The primary endpoint is the proportion of patients with a positive CPA test on tumour and cervical samples. This is defined as the ratio of the number of patients with a positive test on tumour and cervical samples to the total number of evaluable patients (i.e. those with interpretable test results).

The tissue analysis will serve as a negative control for each patient.

For each patient at baseline

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Clinical ans pathological data description
Time Frame: At baseline
The various clinical and pathological data (age, personal and family history of cancer, histological type, tumour cell density and surface area, HRD status, BRCA status, and allelic frequency of the TP53 mutation) will be described using standard descriptive statistics based on the results of tumour and cervical biopsies.
At baseline

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Study Director: Giulio Ricotta, Dr, Institut Claudius Regaud

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 5, 2025

Primary Completion (Estimated)

January 4, 2027

Study Completion (Estimated)

January 4, 2027

Study Registration Dates

First Submitted

September 8, 2026

First Submitted That Met QC Criteria

September 11, 2026

First Posted (Actual)

September 16, 2026

Study Record Updates

Last Update Posted (Actual)

September 16, 2026

Last Update Submitted That Met QC Criteria

September 11, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

There is not a plan to make IPD available

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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