The Irish Experience with Sacrococcygeal Teratomas: Are Type IV Lesions More Common than We Think?

Introduction Sacrococcygeal teratomas (SCTs) are rare tumors occurring in approximately 1 in 35,000 to 40,000 live births. The Altman classification is used to describe SCTs. There are four types, with type 1 predominantly external through to type IV which is a presacral, completely internal mass. As far as the authors are aware, this is the first study to focus on type IV SCT lesions.Materials and Methods Using ICD-10- AM (The International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification) codes, we identified all patients in the Republic of Ireland with a diagnosis of SCT from 2004 to 2020. The following information was obtained for each patient: gender, time of diagnosis, clinical presentation, method of diagnosis, Altman classification, biomarkers, age at operation, surgical technique, pathology, recurrence, and age at most recent follow-up.Results There were 29 patients in total; 23 females (79%) and 6 males (21%). In total, 16 (55%) were diagnosed antenatally, 4 (14%) at less than 1 month, 4 (14%) less than 1 year, 3 (10%) age 2 to 4 years, and 2 (7%) were aged 5 to 12 years. In addition, 22 (76%) were mature teratomas, 2 (7%) immature teratomas, and 5 (17%) were malignant tumors. There were 6 (21%) type I lesions, 9 (30%) type II, 6 (21%) type III, and 8 (28%) type IV lesions.Conclusion In Altman's original 1974 study, type IV lesions were present in 10% of cases. As a result, this is the most frequently quoted figure. Type IV lesions were present in 28% of cases in our study. We propose that type IV lesions may be more common than the current literature suggests and consequently a higher index of suspicion of their presence should be entertained.

Automated summary

This study focused on type IV sacrococcygeal teratomas (SCTs), which are rare tumors. The study included 29 patients in Ireland from 2004 to 2020. The results showed that type IV lesions accounted for 28% of the cases, suggesting that they may be more common than previously believed.