Introduction: Oral mucositis is one of the most frequent complications associated with chemotherapy, occurring in up to 90% children receiving treatment for cancer. Different treatment modalities have been suggested with inconsistent results. Recently, it has been suggested that the use of laser could reduce the grade of oral mucositis and alleviate the symptoms.

Aim: To evaluate and compare the efficacy between the high (Infrared) wavelength laser and low (red) wavelength laser in management of chemotherapy induced oral mucositis in children with acute lymphoblastic leukemia.

Methods: This study is a randomized, prospective, double-blind trial that will include acute lymphoblastic leukemia inpatients receiving induction chemotherapy between the age of 3 and 14years who develop oral mucositis grade 2 or more. These patients will be randomized by the Clinical Epidemiology unit using a computer-based method into three groups. Group I: will be treated with Laser wavelength 660 nm, group II: will be treated with laser wavelength 970 nm, and group III: will receive mock treatment which is the exact repetition of the treatment modality but without any laser emission. All the patients will follow the hospital standard management for oral mucositis. All patients will be assessed for pain score using CHIMES, oral mucositis using NCI-CTCAE scale V5 on days, 0,4,7 and 11. As well as measuring the duration of the lesion.

This study is a randomized, prospective, double-blind trial that will include acute lymphoblastic leukemia inpatients receiving induction chemotherapy between the age of 3 and 14 years who develop oral mucositis grade 2 or more. These patients will be randomized by the Clinical Epidemiology unit using a computer-based method into three groups.

Group I: will be treated with Laser wavelength 660 nm, Group II: will be treated with laser wavelength 970 nm, Group III: will receive mock treatment which is the exact repetition of the treatment modality but without any laser emission.

All the patients will follow the hospital standard management for oral mucositis.

All patients will be assessed for

1. Pain score using CHIMES,
2. Oral mucositis using NCI-CTCAE scale V5 on days, 0,4,7 and 11.
3. Measuring the duration of the lesion.

Inclusion Criteria:

1. Patients with Acute Lymphoblastic Leukemia in the induction therapy phase and have oral mucositis grade 2 or more.
2. Age: 3-14 years old of both genders.
3. No previous treatment with laser.
4. Ability to open mouth for more than 2 cm for the duration of laser application with a level of cooperation (Frankl rating 3 or 4).
5. Patients who still have 10 days in their induction therapy phase or can be followed up for a mininum of 10 days after the development of oral mucositis

Exclusion Criteria:

1. Patients receiving radiotherapy
2. Received oral Cryotherapy or IV keratinocyte growth factor for oral mucositis
3. Patients with unstable clinical condition (e.g. sepsis)
4. Patients who will be withdrawn from participation according to their request or due to loss in follow up

The outcome evaluator will be a single personnel from the oncology team following up with the case.