title: Collins' law. Prediction of recurrence or cure in childhood medulloblastoma?
abstract: Collins' law, known as period of risk for recurrence (PRR), has been discussed as a reliable scheme for the prediction of recurrence or cure of embryonal tumours including medulloblastomas. The PRR is defined as the age at diagnosis plus 9 months of gestation. According to Collins' law, a patient who has no clinical evidence of recurrence within this time period is considered cured. We have applied this system to 66 patients (age range from 0 to 47 years) who underwent surgery for medulloblastoma at a single center between 1975 and 1990. Three patients in whom a recurrence could not be verified died within 6 months. Eight patients (12.1%, age range from 1 to 14 years) survived the PRR without relapse and are free of risk for recurrence according to Collins' law. Of the remaining 55 patients, 35 showed a relapse within the PRR with a mean latency of 18 months (0-78); Twenty patients are alive with no recurrence as yet, but are still within the PRR Three patients had non-recurrent benign brain tumours not connected to the initial tumours with a mean latency of 10 (8-14) years after medulloblastoma surgery. Thus, all our patients fulfilled the criteria for Collins' law. In conclusion, a patient's risk for medulloblastoma recurrence is significantly higher before than after the completion of the PRR. Therefore, the PRR is a helpful prognostic parameter that provides additional information about the risk of medulloblastoma recurrence. A medulloblastoma cure cannot be presumed with certainty by Collins' law because relapses after the PRR have been reported in other studies (1.4% of the cases). Intracranial lesions detected after a long follow-up might be radiotherapeutically induced second tumours.
authors.affiliation: Neurochirurgische Universitätsklinik RWTH Aachen, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Sure
authors.forename: W J
authors.initials: WJ
authors.lastname: Berghorn
authors.forename: H
authors.initials: H
authors.lastname: Bertalanffy
mesh_terms: D000293:Adolescent; D000328:Adult; D002423:Cause of Death; D002528:Cerebellar Neoplasms / Q000401:mortality* / Q000532:radiotherapy / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D008527:Medulloblastoma / Q000401:mortality* / Q000532:radiotherapy / Q000601:surgery; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000532:radiotherapy / Q000601:surgery; D009381:Neoplasms, Radiation-Induced / Q000401:mortality; D016609:Neoplasms, Second Primary / Q000401:mortality; D018714:Radiotherapy, Adjuvant; D018570:Risk Assessment; D015996:Survival Rate