Sung, L., Tomlinson, G.A., Greenberg, M.L., Koren, G., Judd, P., Ota, S., & Feldman, B.M. (2007). Serial controlled N-of-1 trials of topical vitamin E as prophylaxis for chemotherapy-induced oral mucositis in paediatric patients. European Journal of Cancer, 43, 1269–1275.
 

DOI Link

Intervention Characteristics/Basic Study Process

Eight hundred mg vitamin E was diluted with corn oil (volume = 2 mL). Patients swished for at least 30 seconds then spat it out. The control group received corn oil only. Subjects did not rinse mouths for 30 minutes after spitting out the solution. Forty-five cycles of the study drug were administered (one cycle: four patients, two cycles: five patients, three cycles: one patient, four cycles: four patients, six cycles: five patients; vitamin E = 22 cycles, placebo = 23 cycles).

Sample Characteristics

  • N = 16
  • AGE: Pediatric patients aged 6–18 years
  • KEY SAMPLE CHARACTERISTICS: Planned chemotherapy for two identical cycles of doxorubicin-containing chemotherapy with doxorubicin at least 60 mg/m2. Patients had chemotherapy regimens with one to three treatment sets consisting of two to six doxorubicin-containing chemotherapy cycles.


 

Study Design

  • Randomized, controlled, double-blind N-of-1 Bayesian analysis study

Measurement Instruments/Methods

  • Oral Mucositis Assessment Scale (OMAS) days 7, 10, 14, and 17 of each cycle
  • Visual analog scale (VAS) score for pain and difficulty swallowing
  • World Health Organization (WHO) scale in diary by participant or parent
  • Amount of opioid analgesia
  • Topical oral analgesia
  • IV hydration
  • Total parenteral nutrition
  • Episodes of febrile neutropenia
     

Results

Compliance was 84% with no statistically significant findings. Vitamin E was not associated with reduction in pain VAS scores or swallowing difficulty. WHO mucositis scores were similar for vitamin E and placebo cycles. No differences for the additional secondary outcomes between vitamin E and placebo cycles were found. Authors noted that vitamin E should not be used in this context. N-of-1 study design was found to be a potentially effective design method.
 

Limitations

  • Small study
  • Data collection issues
  • No significant findings
  • The order in which the placebo and vitamin E cycles were administered is unclear.