Whole exome sequencing in relapsed or refractory childhood cancer: case series.

Background: The prognosis for relapsed or refractory childhood cancer is approximately 20%. Genetic alterations are one of the significant contributing factors to the prognosis of patients.

Objective: To investigate the molecular profile of relapsed or refractory childhood cancers in Thai cases.

Methods: The study design is a descriptive study of patients <18 years old, suspected or diagnosed of relapsed or refractory childhood cancer who underwent whole exome sequencing (WES).

Results: WES was successfully performed in both the tumor and the blood or saliva samples obtained from 4 unrelated patients. Six different variants were identified in the , , , and genes. These alterations were found to be associated with tumor aggressiveness.

Conclusion: This study is the first one to demonstrate genetic alterations by using WES in relapsed or refractory childhood cancer in Thai cases.