Nephroblastoma--a 25-year review of a South African unit

Abstract

Rationale: To determine the outcome of patients with nephroblastoma in a South African hospital.

Objective: To determine if there is a difference in the outcome of patients with nephroblastoma comparing two treatment protocols SIOP (Société International D'Oncologie Pédiatrique Protocol) versus NWTS (National Wilms' Tumour Study Protocol).

Methods and results: A retrospective audit of 25 years (1983-2007), of children diagnosed with nephroblastoma in Tygerberg Hospital. One hundred and seven patients were included in the study and 98 were analyzed. The average age at diagnosis was 3.8 years. Most patients (37%) presented with stage 1 of the disease, followed by patients with stage 3 (27%). Most patients were treated according to the SIOP protocol (61%). Gender and race did not influence the outcome. Patients with stage 1 and 2 of the disease had the best outcome (76% versus 43% for stages 3 and 4). The SIOP group had a better outcome than the NWTS group (p value 0.001). The two groups had an equal distribution of the stage of presentation. The tumor volumes were bigger in the NWTS group (1004cm3 compared to 613cm3). Nutritional status did not influence the outcome although more patients were underweight for age in the SIOP group. The statistical methods used were: Kaplan Meier, Gehan's Wilcoxon Test, Chi -square test and the Fisher exact test.

Discussion: Contrary to the other studies, patients treated according to the SIOP protocol had a statistically significant better outcome. Larger collaborative studies are needed to investigate this result in Africa.

Keywords: NWTS = National Wilms’ Tumor Study Protocol; SIOP = Société International D’Oncologie Pédiatrique Protocol.

Fig. 1

Correlation of survival with the ethnic group

Fig. 2

Correlation of stages and outcome (p-value=0.01)

Fig. 3

Comparing the outcomes of the stages treated with the NWTS protocol

Fig. 4

Comparing the outcomes of the stages treated with the SIOP protocol