Adherence to childhood cancer treatment: a prospective cohort study from Northern Vietnam.

Objectives: Global incidence and attention to childhood cancer is increasing and treatment abandonment is a major cause of treatment failure in low- and middle-income countries. The purpose of this study was to gain an understanding of factors contributing to non-adherence to treatment.

Design: A prospective cohort study with 2 year follow-up of incidence, family-reported motives and risk factors.

Setting: The largest tertiary paediatric oncology centre in Northern Vietnam.

Participants: All children offered curative cancer treatment, from January 2008 to December 2009.

Primary And Secondary Outcome Measures: Family decision to start treatment was analysed with multivariable logistic regression, and family decision to continue treatment was analysed with a multivariable Cox model. This assessment of non-adherence is thereby methodologically consistent with the accepted definitions and recommended practices for evaluation of treatment abandonment.

Results: Among 731 consecutively admitted patients, 677 were eligible for treatment and were followed for a maximum 2 years. Almost half the parents chose to decline curative care (45.5%), either before (35.2%) or during (10.3%) the course of treatment. Most parents reported perceived poor prognosis as the main reason for non-adherence, followed by financial constraints and traditional medicine preference. The odds of starting treatment increased throughout the study-period (OR 1.04 per month (1.01 to 1.07), p=0.002), and were independently associated with prognosis (OR 0.51 (0.41 to 0.64), p=<0.0001) and travel distance to hospital (OR 0.998 per km (0.996 to 0.999), p=0.004). The results also suggest that adherence to initiated treatment was significantly higher among boys than girls (HR 1.69 (1.05 to 2.73), p=0.03).

Conclusions: Non-adherence influenced the prognosis of childhood cancer, and was associated with cultural and local perceptions of cancer and the economic power of the affected families. Prevention of abandonment is a prerequisite for successful cancer care, and a crucial early step in quality improvements to care for all children with cancer.