ESTRO ACROP guideline for target volume delineation of skull base tumors

AbstractBackground and purpose For skull base tumors, target definition is the key to safe high-dose treatments because surrounding normal tissues are very sensitive radiation. In present work we established a joint ESTRO ACROP guideline for volume of tumors. Material methods A comprehensive literature search was conducted in PubMed using various combinations following medical subjects headings (MeSH) free-text words: "radiation therapy" or "stereotactic radiosurgery" "proton "particle beam "skull neoplasms" "pituitary neoplasms", "meningioma", "craniopharyngioma", "chordoma", "chondrosarcoma", "acoustic neuroma/vestibular schwannoma", "organs at risk", "gross tumor volume", "clinical "planning "target delineation", "dose constraints". The committee identified sixteen European experts close interaction with clinical who analyzed discussed body evidence concerning delineation. Results All agree that magnetic resonance (MR) images high three-dimensional spatial accuracy tissue-contrast definition, both T2-weighted volumetric T1-weighted sequences, required improve detail, several issues were discussed: i) radiation techniques immobilization, ii) imaging delineation, iii) technical aspects including planning dose-fractionation schedules. Specific delineation regard different pituitary adenomas, meningiomas, craniopharyngiomas, acoustic neuromas, chordomas chondrosarcomas presented. Conclusions This achieved detailed recommendations on as well advice about modalities techniques.