More than half of all pediatric cancer in Korea are solid cancer. For the treatment of solid cancer, multidisciplinary methods such as surgery, chemotherapy, and radiation therapy are applied, and with the development of the treatment method, the treatment performance has improved dramatically, and the 5-year survival rate of more than 80% is currently recorded. Due to the improvement in survival rate, interest in side effects caused by cancer treatment itself is gradually increasing, and efforts to reduce them are increasing. Accordingly, it aims to contribute to improving the quality of life of pediatric solid cancer survivors. by developing a Korean-type early diagnosis and follow-up protocol of ototoxic hearing loss, which commonly occurs in pediatric solid cancer who have undergone chemotherapy.

Inclusion Criteria:

① Solid cancer patients under the age of 19 receiving Platinum chemotherapy

② Solid cancer patients under the age of 19 receiving 30 Gy or more head and neck radiation therapy

Exclusion Criteria:

① Those who have received chemotherapy or radiation in the past

• Those who have difficulty understanding the clinical trial due to mental retardation or unable to read the consent form, such as illiteracy or foreigners ③ Those who have difficulty in hearing test due to neurological factors, etc. ④ Other cases judged to be inappropriate for this study by the judgment of the person in charge of the clinical trial

Patients who are diagnosed as solid cancer and receive platinum chemotherapy