Electronic nose for breath analysis after curative Surgery to detect distant metastases or locoregional recurrence of colon cancer

Rationale
Colorectal carcinoma (CRC) has a high incidence worldwide and in the Netherlands. After curative treatment, there is a risk of recurrence of 15%. Early detection of an asymptomatic recurrence can still lead to curative treatment. The current follow-up studies do not have optimal sensitivity and specificity.
Multiple studies have demonstrated that volatile organic compound (VOC) analysis has a high diagnostic accuracy for CRC. Furthermore, a pilot study has recently shown that there is a distinctive character in VOC in patients after curative resection of CRC with and without recurrence.

Objective
In this study it is investigated whether eNose is able to distinguish patients with recurrent CRC after curative resection from patients without recurrent CRC based on VOC patterns. The primary outcome measure is the diagnostic accuracy of eNose in the detection of recurrent CRC

Study design
This study concerns a prospective validation study as a follow-up to the pilot study that was carried out

Study population
All patients with AJCC stage I-IV CRC after a R0 resection, and are offered follow-up according to Dutch guidelines are asked to participate. Patients with stage IV (synchronous or metachronous metastases) who have been treated with curative intention are included. Patients with a local resection and a pT1N0Mx are excluded.
Intervention
Patients are given a breath test during the first three years of follow-up when they come for a regular follow-up with imaging. If verification of only CEA determination (year 4 and 5) gives rise to imaging tests, they will be asked for an extra breath test.

Main study endpoint
We want to demonstrate a sensitivity of at least 70% using the eNose to detect recurrent CRC.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness
Patients do not directly benefit from participating in this study. The outcome of the breath test is not shared with patients and practitioners and has no treatment consequences. Nevertheless, participation in this study is not associated with any health risk and the burden to the patient is a 5 minute breath test at a time when the patient enters the hospital for standard follow-up examinations.

eNose is able to detect metastases of CRC with a sensitivity of at least 70%

The primary outcome measure is the diagnostic accuracy of eNose in the detection of recurrent CRC. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy are calculated after the achieved numbers of patients are included. This is expected on 01-03-2023

Patients are given a breath test during the first three years of follow-up if they come for a regular follow-up with imaging. If verification of only CEA determination (year 4 and 5) gives rise to imaging tests, they will be asked for an extra breath test