CT Carcinogenic Risk in Patients With Appendicitis

Carcinogenic Risk of CT in Patients With Appendicitis

The purpose of this study is to compare the incidence rate of leukemia between CT-exposed and CT-unexposed group in patients who underwent appendectomy in South Korea.

Study Overview

• Status: Unknown
• Conditions: Appendicitis; Carcinogenesis; Radiation Exposure; Computed Tomography
• Intervention / Treatment: Radiation: Abdomen CT

Detailed Description

South Korea has a single-payer healthcare system, administered by National Health Insurance Service (NHIS). As healthcare providers in South Korea need to claim reimbursement to NHIS for the vast majority of diagnostic and therapeutic procedures, the NHIS database enabled us to construct a large cohort who did or did not undergo CT for appendicitis. The purpose of this study is to compare the incidence rate of cancer between CT-exposed and CT-unexposed group in patients who underwent appendectomy in South Korea.

• Study Type: Observational
• Enrollment (Anticipated): 1000000

Contacts and Locations

• Study Contact: Name: Ji Hoon Park, MD; Phone Number: 82-10-8526-0650; Email: pjihoon79@gmail.com
• Study Contact Backup: Name: Kyung Hee Lee, MD; Phone Number: 82-10-6686-8404; Email: kyung8404@gmail.com

Study Locations

• Korea, Republic of
  • Gyeonggi-do
    • Seongnam-Si, Gyeonggi-do, Korea, Republic of, 463-707
      • Recruiting
      • Seoul National University Bunadang Hospital
      • Contact: Min Jeong Jeong; Phone Number: 82-31-787-7607; Email: jeongminjeong1004@gmail.com

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Patients who underwent appendectomy under the diagnosis of appendicitis

Description

Inclusion Criteria:

• Patients will be entered in the cohort on the date of appendectomy under the diagnosis of appendicitis

Exclusion Criteria:

• (a) patients who had a cancer diagnosis before the date of appendectomy,
• (b) those who had prior experience of CT examination more than 7 days before appendectomy,
• (c) those who had syndromes or diseases predisposing cancers,
• (d) those whose diagnosis was changed to appendiceal cancer and
• (e) those whose follow-up duration was shorter than a lag period.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
CT-exposed group	Radiation: Abdomen CT; Patients are divided into CT-exposed or unexposed group according to the presence of claims codes of abdominopelvic CT conducted within seven days before and after appendectomy. The seven-day threshold is arbitrarily determined considering the delay in the diagnosis of appendicitis and the postoperative examination for surgical complication.
CT-unexposed group	Radiation: Abdomen CT; Patients are divided into CT-exposed or unexposed group according to the presence of claims codes of abdominopelvic CT conducted within seven days before and after appendectomy. The seven-day threshold is arbitrarily determined considering the delay in the diagnosis of appendicitis and the postoperative examination for surgical complication.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Age and sex-standardized incidence rate ratio (IRR) for malignancies of hematologic system	Hematologic malignancies are categorized into lymphomas, multiple myeloma, leukemias, myelodysplasia and others using ICD-10 codes.	Cancer occurrence after a lag period (2 years)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Age and sex-standardized incidence rate ratio (IRR) for malignancies of abdominal organs	age and sex-standardized IRRs for malignancies of abdominal organs for CT-exposed versus unexposed patients.	Cancer occurrence after a lag period (2 years)
Age and sex-standardized incidence rate ratio (IRR) for all cancers	age and sex-standardized IRRs for all cancers for CT-exposed versus unexposed patients.	Cancer occurrence after a lag period (2 years)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sensitivity analysis	Various lag periods will be applied for the outcomes.	Cancer occurrence after different lag periods (6 months, 1 year, 3 years and 5 years)
Subgroup analysis by subsequent CT scans conducted more than 7 days after appendectomy	IRR in patients who underwent CT after appendectomy IRR in patients who did not undergo CT after appendectomy	CT undergone more than 7 days after appendectomy will be counted.
Subgroup analysis	by age and sex	Cancer occurrence after a lag period (2 years)

Collaborators and Investigators

• Sponsor: Seoul National University Bundang Hospital
• Collaborators: National Research Foundation of Korea

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2018
• Primary Completion (Anticipated): December 15, 2020
• Study Completion (Anticipated): May 15, 2021

Study Registration Dates

• First Submitted: December 13, 2018
• First Submitted That Met QC Criteria: December 13, 2018
• First Posted (Actual): December 14, 2018

Study Record Updates

• Last Update Posted (Actual): February 17, 2020
• Last Update Submitted That Met QC Criteria: February 12, 2020
• Last Verified: February 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Digestive System Diseases; Pathologic Processes; Infections; Neoplasms; Gastrointestinal Diseases; Gastroenteritis; Intestinal Diseases; Neoplastic Processes; Cecal Diseases; Intraabdominal Infections; Appendicitis; Carcinogenesis
• Other Study ID Numbers: AppyCTcancer

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