Outcome of two cohorts with nephroblastoma treated with consecutive International Society of Paediatric Oncology protocols in a South African paediatric oncology unit
Date
2021-12
Authors
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Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: Background: Nephroblastoma is a common childhood solid tumour in South Africa.
Aim and objectives: The primary aim was to assess the outcome of patients diagnosed with nephroblastoma between 1990 and 2018. The primary objective was to compare the outcomes of two cohorts of patients between 1990 and 2018 treated with consecutive International Society of Paediatric Oncology (SIOP) protocols that had been designed for nephroblastoma. Secondary objectives were to determine the association between surgical complications, lymph node sampling and histological types, and overall survival (OS) and event-free survival (EFS).
Methods: This was a retrospective, descriptive study of two cohorts in the Paediatric Oncology Unit, Tygerberg Hospital. Cohort 1 (1990-2007) was treated with the SIOP 9 and SIOP 93-01 protocols. The SIOP 2001 protocol was used to treat Cohort 2 (2008-2018). All treatment-naïve children diagnosed with a nephroblastoma under the age of 16 years were included. Data included demographic data (age at diagnosis and sex), socioeconomic status, HIV status, pre- and postoperative staging, surgical complications, sampling of lymph nodes, histological types, OS and EFS. The OS and EFS end points were two years from diagnosis.
Results: There were 60 children (M:F ratio 1:1.14) in Cohort 1 versus 45 children (M:F ratio 1:0.8) in Cohort 2. Cohort 1 had an older mean age (42 months, median 35, IQR 16.25-56.5 months) than Cohort 2 (mean 37 months, median 33, IQR 22-45.5 months). Cohort 2 had more patients with limited disease (76%) versus 55% for Cohort 1. This probably indicates earlier diagnosis with a trend towards significance (p-value 0.076). Metastatic disease was more prevalent in Cohort 1 (18%; 11/60) than in Cohort 2 (13%; 7/45), although numbers were too small to determine significance. Both cohorts had a good OS (respectively 93% and 88%) and EFS (respectively 80% and 82%) with no statistical difference. Surgical complications were similar for both cohorts, respectively 10% (4/60) for Cohort 1 and 7% (4/60) for Cohort 2. Half of Cohort 1 (50%; 30/60) did not have lymph nodes sampled with four subsequent relapses, significantly associated with OS (p = 0.000) and EFS (p = 0.006), probably due to incorrect postoperative staging. Lymph node sampling was done in 75% in Cohort 2, with no association with OS and EFS, indicating improved postoperative staging. The predominant histology type was triphasic for both cohorts with significant association between OS and EFS and underlying histology (respectively p-value 0.006 and p-value 0.015) for Cohort 1 but only significant association between EFS and histology (p = 0.02) for Cohort 2. Conclusion: In South Africa, an upper-middle-income country, children with nephroblastoma treated with SIOP protocols have a good OS. Lymph node sampling was essential to determine the correct postoperative stage with improved outcome.
AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar.
AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar.
Description
Thesis (MPhil)--Stellenbosch University, 2022.
Keywords
Nephroblastoma, Paediatric oncology -- South Africa, Metastasis - South African, Lymph nodes -- Cancer, Tumors -- Surgery, Postoperative care, UCTD