Background: The aim of the study was to evaluate the risk of malignant conversion in pediatric teratomas.
Material and methods: The records of 18 patients with teratomas (12 girls and 6 boys), aged 2 days to 15 years (mean 4.87) treated between 1993 and 2002 were reviewed. OPD follow-up (US, AFP) was carried out for five years after surgery. One girl (5.5%) from the analyzed group died and the remaining 17 patients (94.5%) completed the therapy and are free of disease with a follow up period ranging from 2 to 10 years (mean 4.67 years).
Results: Tumours were primary localized in the ovaries in 7 girls (38,9%), in the sacrococcygeal region in 6 children (33.4%), in the testicles in 3 boys (16.7%), in the mediastinum in one patient (5.5%) and in the thorax in one instance (5.5%). Thus, gonadal locations were observed in 10 children (55.6%) and extragonadal in 8 patients (44.4%). After a primary resection of the tumour, mature teratomas were diagnosed in 17 patients (94.5%), and a yolk sac tumour (IVs) in one girl (5.5%). Six children (33.3%) underwent surgery in the neonatal period.
Out of 7 girls with ovarian tumours, one (14.3%) was operated on during the neonatal period, 4 patients (57.1%) were asymptomatic and the tumour was detected inadvertently, and in 2 instances (28.6%) torsion of the ovary occurred. The mean age of girls with ovarian teratomas was 6.7 years. Female prevalence (5 [83.4%]) was observed in the group of 6 patients with sacrococcygeal tumours. The mean age of the 3 boys with testicular tumours was significantly lower than the mean age of girls with ovarian teratomas (1.7 vs. 6.7 years). Local recurrence of the tumour was observed in two children (11.2%) after a primary excision of the sacrococcygeal tumour in the neonatal period. Malignant conversion of neoplasms was observed in two patients (16.7%) with recurrent tumours and in a girl with a type IV tumour diagnosed at the age of 3.5 years. One of these children (5.5%) died due to the disease’s progression. Complications rates in patients with sacrococcygeal tumours were respectively: local recurrence - 33.4% (2/6), malignant conversion - 50% (3/6), deaths - 16.7% (1/6).
Conclusions: Sacrococcygeal location should be considered a high risk factor in malignant conversion in paediatric teratomas. Thus, early primary surgical resection of the tumour with an adequate bone segment, verified histologically and a follow-up for 5 years after surgery (US, AFP) is recommended.