Tsujimoto, T., Yamamoto, Y., Wasa, M., Takenaka, Y., Nakahara, S., Takagi, T., . . . Ito, T. (2014). L-glutamine decreases the severity of mucositis induced by chemoradiotherapy in patients with locally advanced head and neck cancer: A double-blind, randomized, placebo-controlled trial. Oncology Reports, 33, 33–39.

To investigate whether L-glutamine (glutamine) decreases the severity of mucositis in the oral cavity, pharynx, and larynx induced by chemoradiotherapy (CRT)

Patients with squamous cell carcinoma of the nasopharynx, oropharynx, hypopharynx, or larynx (HNC) receiving CRT were randomized to orally receive either glutamine (group G) or placebo (group P) at a dose of 10 g three times per day throughout the CRT course.

• N = 40
• AGE RANGE = 38–77 years
• MALES: 34 (85%), FEMALES: 6 (15%)
• KEY DISEASE CHARACTERISTICS: Primary squamous cell carcinoma of the nasopharynx, oropharynx, hypopharynx, or larynx

• SITE: Single-site    
• SETTING TYPE: Inpatient  
• LOCATION: Osaka University Hospital, Japan

• PHASE OF CARE: Active antitumor treatment
• APPLICATIONS: Elder care

Double-blinded, randomized, placebo-controlled trial that excluded patients with active mouth or throat soreness before treatment, uncontrolled diabetes mellitus, or severe renal or hepatic insufficiency.

• Images of laryngoscope using the National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 3
• Hematologic and blood chemistry tests were performed at baseline, once per week during the study treatment (weeks one to six), and after treatment (weeks seven to nine) or until patient discharge, whichever occurred first.
• Pain score according to a numerical rating scale (NRS) 
• The primary treatment outcome was evaluated 10 weeks after the completion of treatment using computed tomography (CT), positron emission tomography-CT (PET-CT), and biopsy.

The study demonstrated that glutamine significantly decreased the severity of CRT-induced mucositis in patients with HNC. Patients (group G) receiving glutamine had a decreased the incidence of grade 4 mucositis. The mean duration of supplemental nutrition because of severe mucositis was significantly shorter in group G than in group P (group G, 18 ± 13; group P, 27 ± 11; p = .046). Treatment delay caused by mucositis was observed in zero patients in group G and in 15% of patients in group P. In addition, NRS scores were significantly lower in group G than in group P at weeks 4, 5, and 6 (p = .049, p = .019, p = .032, respectively).

The study showed that glutamine significantly decreases the severity of CRT-induced mucositis in patients with cancer, which in turn will improve quality of life for patients.

• Small sample (< 100)

This study could not provide conclusive results of glutamine in the prevention and treatment of oral mucositis. The study indicated the need for an integrative and multidisciplinary approach in patient care, which could result in substantial advances in the outcomes of cancer therapy and the improvement in patient quality of life. However, there is no known specific dose for glutamine, and it has not been approved by the U.S. Food and Drug Administration for the treatment of mucositis during chemoradiotherapy.