Impact of COVID-19 Pandemic Waves on Colorectal Cancer Stage Migration and Diagnostic Delays

Background/Objectives: The incidence of colorectal cancer in Hungary exceeds the EU (European Union) average, and the cancer mortality rate is also among the highest in the country. The COVID-19 pandemic has impacted various areas of healthcare, including cancer diagnosis and treatment. Due to the measures taken to combat the COVID-19 pandemic, not only newly suspected cancer patients but also those already diagnosed and undergoing treatment faced numerous difficulties. Methods: The study included 198 patients with colorectal cancer, of whom 43 participants were newly diagnosed cases. Due to low case numbers in certain COVID-19 waves, adjacent waves were merged for statistical analysis. The number of newly diagnosed colorectal cancer cases across COVID-19 waves was compared using one-way ANOVA, stage distribution differences and the proportion of missed treatments were assessed with Fisher's exact test. In follow-up patients, changes were analyzed using the Wilcoxon signed-rank test. Differences in tumor size categories were examined using chi-square tests.

Study Overview

• Status: Completed
• Conditions: Colorectal Cancer

• Study Type: Observational
• Enrollment (Actual): 198

Contacts and Locations

Study Locations

• Hungary
  • Budapest, Hungary, 1032
    • Szent Margit Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients with colorectal cancer undergoing MRI examination during and after the COVID-19 pandemic.

Description

Inclusion Criteria:

• Patients with suspected or confirmed colorectal cancer
• Patients examined by MRI at Szent Margit Hospital
• MRI referral issued between September 2020 and December 2023

Exclusion Criteria:

• MRI referrals not issued by Szent Margit Hospital

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Colorectal cancer patients; Patients with colorectal cancer undergoing MRI examination during and after the COVID-19 pandemic.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tumor stage distribution across COVID-19 pandemic waves	Comparison of colorectal cancer tumor stage (AJCC 8th edition) across different COVID-19 pandemic waves and the post-COVID period based on MRI findings.	September 2020 - December 2023
Number of newly diagnosed colorectal cancer cases	Monthly number of newly diagnosed colorectal cancer cases across COVID-19 waves and the post-COVID period.	September 2020 - December 2023
TNM classification	TNM classification of colorectal cancer according to the AJCC 8th edition during different COVID-19 pandemic waves in newly diagnosed and follow-up patients.	September 2020 - December 2023

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tumor progression or regression in follow-up patients	Change in tumor stage between previous imaging and most recent MRI examination.	September 2020 - December 2023
Missed oncologic treatments	Occurrence of missed or delayed oncologic treatments documented during the COVID-19 pandemic period.	September 2020 - December 2023
Presence and distribution of metastases	Presence, number, and organ distribution of metastatic disease based on imaging findings.	September 2020 - December 2023

Collaborators and Investigators

• Sponsor: University of Pecs
• Investigators: Principal Investigator: József Tollár, Dr., University of Pécs, Faculty of Health Sciences, Hungary; Principal Investigator: Adrienn Biró, Dr., Somogy County Móricz Kaposi Teaching Hospital, 7400 Kaposvár, Hungary

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2020
• Primary Completion (Actual): December 31, 2023
• Study Completion (Actual): December 31, 2023

Study Registration Dates

• First Submitted: December 14, 2025
• First Submitted That Met QC Criteria: January 3, 2026
• First Posted (Actual): January 9, 2026

Study Record Updates

• Last Update Posted (Actual): January 9, 2026
• Last Update Submitted That Met QC Criteria: January 3, 2026
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: colorectal cancer; COVID-19; follow-up; pandemic waves
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Intestinal Diseases; Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Neoplasms; Rectal Diseases; Lung Diseases; Colonic Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; COVID-19; Colorectal Neoplasms
• Other Study ID Numbers: IG/2037-1/2023

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No