CAYA Cancer Retrospective Cohort Study

Improving Cancer Outcomes for Children, Adolescents, and Young Adults: A Multicenter Retrospective Cohort Study on Treatment Failure and Toxicity in Low- and Middle-Income Countries

Despite advances in cancer treatment, significant disparities in outcomes persist between high-income countries (HICs) and low-and middle-income countries (LMICs). Around 80% of children with cancer live in LMICs, where they face challenges such as delayed diagnosis, misdiagnosis, comorbidities, distance to treatment, financial barriers, and limited access to risk-adapted therapies.

Acute lymphoblastic leukemia(ALL)/lymphoblastic lymphoma(LBL), for example, is one of the greatest success stories in pediatric oncology, however, such improvements are not evenly distributed worldwide, and the outcomes for leukemia patients are poorer in LMICs compared to HICs, primarily due to reduced access to quality healthcare.

This study aims to assess cancer treatment outcomes in LMICs, focusing on acute lymphoblastic leukemia/lymphoblastic lymphoma. The findings will inform future studies to implement evidence-based interventions that improve care quality and reduce treatment failures through targeted strategies.

Inclusion Criteria:

Subjects must meet all the following criteria to be included in this registry:

1. Participants must be willing and able to provide informed consent prior to enrollment in the registry.

   1. For minors or individuals unable to provide informed consent, assent must be obtained along with consent from a legal guardian.
   2. Note: Exemption applies to this criterion when waiver of informed consent/assent is granted by Institutional Review Board(IRB)/Independent Ethics Committee(IEC)/Competent Authorities(CAs).

2. A confirmed diagnosis of any type of cancer within the 15 years prior to the site's activation date.

3. Age 0 to 21 years at the time of diagnosis.

4. Received substantial anti-cancer treatment at the participating center, including but not limited to:

   1. Chemotherapy
   2. Surgery
   3. Radiation therapy
   4. Immunotherapy

5. Medical records are available and accessible for review

Exclusion Criteria:

• Subjects meeting any of the following criteria will be excluded from this registry:

  1. Patients who only visited the participating center for:

     1. Consultation without subsequent primary anti-cancer treatment at the participating center
     2. Pathology, radiology, or other diagnostic evaluations without treatment