it's a prospective study aiming to improve quality of life of patients with acute lymphoblastic leukemia suffering from oral mucositis, receiving courses of methotrexate chemotherapy , by measuring vitamin D in those patients before induction therapy and the change in its level during treatment, that associated with methotrexate-induced oral mucositis, taking in consideration serum level of methotrexate, so we may have assiotiation between vitamin D difficiency and oral mucositis . at the end we can have preventive interventions to protect against this harmful side effect.

Treatment outcome of acute lymphoblastic leukemia (ALL) is improved recently and the 5-year survival rates reached 90% in developed countries . So more research currently focuses on strategies to decrease toxic adverse effects of methotrexate (MTX). Oral mucositis occurs in about 20% of patients receiving methotrexate Identifying risk factors leading to this side effects would be valuable to develop preventive interventions and improve quality of life for these patients .

Previous studies revealed a relationship between vitamin D deficiency and chemotherapy-induced oral mucositis in cancer patients. This hormone is important in many physiological processes in the body as bone mineralization and immune regulations. The main sourses of Vitamin D is production in the skin through sunlight exposure, diet and Vitamin D supplements .

Previous literature showed that receptors for vitamin D expressed in the mucosa and so there is a relationship between vitamin D deficiency and increase inflammation and impairment of mucosa .

Patients with acute lymphoblastic leukemia maybe at risk of vitamin D deficiency because of impaired vitamin intake and sunlight exposure . In this study we examin the possible role of vitamin D in relation to methotrexate induced oral mucositis in cancer patients.

• peripheral blood samples from patients before starting chemotherapy course with methotrexate and 24 hr after starting the treatment for measurement level of vitamin D, samples centrifuged at the speed of 2000 - 3000 rpm for 20 min , then analyzed using ELISA.
• blood samples after treatment also used to determine serum level of methotrexate which may lead to toxic adverse effect as oral mucositis , samples centrifuged at speed of 2000 - 3000 rpm for 10 min and analyzed using Viva-E equipment.
• All serum samples were stored at -80 °C and analyzed collectively

Inclusion Criteria:

• patients with acute lymphocytic leukemia in South Egypt Cancer Institute
• patients recieving methotrexate in protocol of treatment
• both sex included

Exclusion Criteria:

• patients with other types of tumors
• patients refuse to join the research
• patients with comorbid hepatic or renal impairment

pediatric and old patients with acute lymphocytic leukemia treated with methotrexate based chemotherapy