Mayo Clinic classification of presacral tumors: evolution of classifications and systematic review of pathologies.

BACKGROUND: Presacral tumours are rare, heterogeneous lesions. Historical classification systems for presacral tumours have provided a valuable framework, but were based on limited available data. This study aimed to develop a contemporary classification aligned with current tumour entities and clinical practice. METHODS: A prospectively registered systematic review of surgically managed presacral tumours published from 1975 to 2025 was combined with a retrospective multisite institutional surgical pathology review from 1986 to 2025. Pathological descriptors were extracted, cross-referenced, harmonized to current terminology, and organized through multidisciplinary expert review to obtain a new classification. RESULTS: The systematic review identified 5997 records, of which 203 studies met the inclusion criteria and contributed 181 pathological terms after generic and unclassifiable diagnoses were removed. Review of 3606 pathology reports identified 19 additional terms, bringing the total to 200 pathological terms. After harmonization to current terminology and exclusion of non-neoplastic processes, a contemporary classification was developed using biological descriptors: developmental versus acquired origin; tissue lineage (neurogenic, osseous/haematopoietic, soft tissue, or miscellaneous); and tumour behaviour (benign, locally recurrent without metastatic potential, locally recurrent with low metastatic potential, malignant non-sarcoma, or malignant sarcoma). CONCLUSION: The Mayo Clinic classification of presacral tumours updates historical systems by reflecting the broader, more modern spectrum of neoplasms and distinguishing lesions by lineage and biological behaviour. It may improve diagnostic clarity, communication, and selection of appropriate observation, multidisciplinary assessment, and treatment pathways.