title: Patients with retinoblastoma and chromosome 13q deletions have increased chemotherapy-related toxicities.
abstract: A total of 5-10% of patients with retinoblastoma (RB) harbor deletion of the long arm (q) chromosome 13 (13q-). The treatment-related toxicities in this population have not been described.
  
  
  
  Sixty-eight RB patients on a single institutional protocol (RET5) from 2005 to 2010 were reviewed. Genetic screening identified 11 patients (seven female) with 13q-. Patients with early (Reese-Ellsworth [R-E] group I-III) disease (6/23 with 13q-) received eight courses of vincristine/carboplatin (VC). Patients with advanced (R-E group IV-V) bilateral disease (2/27 with 13q-) received two courses of vincristine/topotecan (VT) followed by nine courses of alternating VT/VC. Patients undergoing upfront enucleation received histopathology-based chemotherapy: intermediate risk (2/8 with 13q-) or high risk (1/10 with 13q-). Dose reductions were mandated for >7 day delay in two consecutive courses following hematologic toxicity. Grades 3 and 4 hematologic, infectious, and gastrointestinal toxicities were compared between RET5 patients with and without 13q-.
  
  
  
  Demographics were similar between groups. When present, prolonged neutropenia (median 7 days, range 0-14 days) delayed chemotherapy and resulted in more frequent dose reductions among 13q- patients (5/11) than non-13q- patients (4/57) (P < 0.01). GI toxicity was similar between groups (5/11 13q- vs. 13/57 non-13q-; P = 0.14), but halted chemotherapy in one 13q- patient. Infectious complications and disease outcomes were similar between groups. At follow-up, all patients are alive (median 6.1 years, range 7.6 months-9.5 years).
  
  
  
  13q- RB patients had a higher incidence of neutropenia requiring chemotherapy dose reductions, but did not have increased treatment failure.
authors.affiliation: Division of Solid Tumor, Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee. Rachel.brennan@stjude.org.|Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee. Rachel.brennan@stjude.org.|Department of Ophthalmology, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee. Rachel.brennan@stjude.org.
authors.forename: Rachel C
authors.initials: RC
authors.lastname: Brennan
authors.affiliation: Division of Solid Tumor, Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee.|Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Qaddoumi
authors.affiliation: Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee.
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Billups
authors.affiliation: Department of Surgery, St. Jude Children's Research Hospital, Memphis, Tennessee.
authors.forename: Tracy
authors.initials: T
authors.lastname: Kaluzny
authors.affiliation: Division of Solid Tumor, Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee.|Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee.
authors.forename: Wayne L
authors.initials: WL
authors.lastname: Furman
authors.affiliation: Department of Surgery, St. Jude Children's Research Hospital, Memphis, Tennessee.|Department of Pathology, St. Jude Children's Research Hospital, Memphis, Tennessee.|Department of Ophthalmology, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee.
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Wilson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects*; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D025063:Chromosome Disorders / Q000150:complications*; D002882:Chromosomes, Human, Pair 13; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D019572:Retinal Neoplasms / Q000188:drug therapy* / Q000235:genetics; D012175:Retinoblastoma / Q000188:drug therapy* / Q000235:genetics
keywords: 13q deletion syndrome; 13q-; chemotherapy-related toxicity; neutropenia; retinoblastoma