Method
Patients were required to fulfil the following criteria for inclusion in this retrospective study: (i) diagnosis of monomorphic PTLD, post-SOT, established by a reference pathologist in accordance with WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues, (ii) commencement of treatment between January 2001 and December 2021, (iii) age ≤19 years at time of diagnosis.
Following research ethics board approval and establishment of data sharing agreements, data abstracted included: age and gender, SOT received, immunosuppressive agents employed, subtype of monomorphic PTLD, stage at presentation (as per Murphy or Ann Arbor), EBV status, primary treatment approach, need for additional lines of treatment, and outcome data: presence or absence of allograft dysfunction, date and status at last follow-up.
Data analysis was primarily descriptive. Overall survival (OS) was defined as time from diagnosis until death from any cause. Event-free survival (EFS) was defined as time from diagnosis until relapse, progressive disease, or death from any cause. OS and EFS were determined using the Kaplan-Meier method with Cox proportional hazard modelling to compare outcomes between chemotherapy groups. P-value ≤0.05 = statistically significant. Statistical analysis was undertaken using R statistical environment (v 3.3.3).