title: Three-dimensional quantitation of pediatric tumor bulk.
abstract: In pediatric oncology, therapeutic decisions are made based on tumor response to chemotherapeutic agents. Sequential measurement of tumor bulk and its percent change on therapy must be accurately assessed. Will 3-dimensional (3-D) volumetric determination improve our ability to assess tumor response to therapy? Forty-five CT scans of pediatric patients with unresectable thoracic or abdominal neoplasia were assessed for tumor bulk by the standard "2-dimensional (2-D)" volume formula (cross-sectional area x length) and by 3-D volumetric analysis. Thirty-two examinations were performed in follow-up, and percent change in tumor size was calculated. The 2-D volume calculation overestimated tumor volume by more than 50% on all but two examinations when the 2-D volume was compared with the 3-D volume. In 28% of follow-up examinations, the 2-D calculation of percent change differed by more than 10% from the 3-D volume. Fifteen percent differed by over 25%. This changed the response category of one patient from "no response" to "partial response". 3-D volumetric analysis, easily performed by a trained technologist, will give more accurate assessment of the actual tumor bulk and its subsequent changes in size in response to therapy.
authors.affiliation: Department of Radiology, Milton S. Hershey Medical Center, Pennsylvania State University, Hershey 17033, USA.
authors.forename: K D
authors.initials: KD
authors.lastname: Eggli
authors.forename: P
authors.initials: P
authors.lastname: Close
authors.forename: P W
authors.initials: PW
authors.lastname: Dillon
authors.forename: M
authors.initials: M
authors.lastname: Umlauf
authors.forename: K D
authors.initials: KD
authors.lastname: Hopper
mesh_terms: D000008:Abdominal Neoplasms / Q000000981:diagnostic imaging; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging; D008113:Liver Neoplasms / Q000000981:diagnostic imaging; D008297:Male; D009369:Neoplasms / Q000000981:diagnostic imaging*; D009447:Neuroblastoma / Q000000981:diagnostic imaging; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*