Determining the effect of oxygen therapy during chemotherapy on 5FU-induced oral mucositis in colorectal cancer patients treated with FOLFOX regimen: A double-blind clinical trial

Determining the effect of oxygen therapy during chemotherapy on 5FU-induced oral mucositis in colorectal cancer patients treated with FOLFOX regimen

A randomized, controlled, parallel-group, double-blind clinical trial with block randomization using blocks of two.

A randomized, double-blind trial at Kosar Hospital, Semnan, in colorectal cancer patients receiving FOLFOX. Patients will be randomized 1:1 to oxygen or room air during 5-FU bolus. The intervention group will receive oxygen via simple face mask for 30 minutes. Mucositis will be assessed by OMAS before treatment and after every two chemotherapy sessions. Participants and outcome assessor will be blinded.

Inclusion Criteria: Non-metastatic colorectal cancer; FOLFOX including 5-FU; age 18–75 years; baseline SpO₂ >92% on room air; willingness and ability to complete treatment and follow-up. Exclusion Criteria: Oxygen intolerance; severe chronic pulmonary disease; active oral infection or significant oral/dental disease; concurrent head/neck radiotherapy; severe renal/hepatic insufficiency; active psychiatric or cognitive impairment; participation in another trial within 3 months; withdrawal or noncompliance with follow-up.

Intervention Group: Patients will receive oxygen therapy via a simple face mask at 2 L/min for 30 minutes during each chemotherapy cycle (usually every two weeks), concurrently with the 5-FU bolus. Oral mucositis severity will be assessed before treatment and after every two chemotherapy sessions. Control Group: Patients will breathe room air normally without oxygen therapy or a mask during 5-FU bolus administration. Mucositis severity will be assessed at the same time points, and outcomes will be compared between groups until the end of follow-up.

Oral mucositis severity

Patients will be randomly allocated to the intervention or control group using block randomization with blocks of two, generated through the Sealed Envelope website. Randomization will be stratified by sex, and patients will be equally allocated to the two study groups.

In this study, participants and the data analyst will be blinded to group allocation. Participants will receive the intervention individually in separate rooms and will not have the opportunity to observe the intervention received by other participants. Information regarding group allocation and the type of intervention will not be disclosed to the participants. In the intervention group, oxygen therapy will be administered via a simple face mask for 30 minutes, while participants in the control group will remain under usual conditions and breathe room air. The intervention will be administered separately to each participant to minimize the possibility of revealing group allocation through observation of other participants. The personnel responsible for administering the intervention and the outcome assessor will not be blinded due to the nature of the intervention and the assessment process. For blinding of the data analyst, participant data will be coded using non-identifiable group codes (e.g., A and B) before statistical analysis. The code key will be kept by the principal investigator until completion of the statistical analysis. Therefore, the data analyst will not know which code represents the intervention or control group during the analysis. The group allocation codes will be revealed after completion of the statistical analysis.