title: Suboptimal chemotherapy is an adverse prognostic factor in osteosarcoma.
abstract: BACKGROUND
  We sought to determine whether suboptimal chemotherapy compromised the prognosis of osteosarcoma patients.
  
  
  METHODS
  A total of 132 eligible patients who underwent chemotherapy between 1998 and 2008 were identified in our database. Information regarding patient demographics, clinical characteristics, and survival status were extracted for analysis. Optimal chemotherapy was defined as receipt of ≥80% of the planned dose intensity of prescribed agents within the planned durations.
  
  
  RESULTS
  The use of optimal chemotherapy resulted in an overall survival benefit with P = 0.006. Patients who failed to complete the optimal chemotherapy protocol had a dismal prognosis of 30.8% overall survival over five years, whereas those who completed the optimal chemotherapy had an overall survival rate over five years of 65.3%. Based on multivariate analysis, patients who were treated with a suboptimal protocol had a higher risk of relapse, metastasis and mortality. The hazard ratio (HR) of recurrence or death for the suboptimal chemotherapy group was as high as 2.512 over that of the optimal chemotherapy group (HR = 2.512, 95% confidence interval = 1.242 to 3.729).
  
  
  CONCLUSIONS
  Chemotherapy is a significant independent prognostic variable, and suboptimal chemotherapy was found to have a detrimental effect on the outcome of patients with osteosarcoma.
authors.affiliation: Musculoskeletal Oncology Department, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China.
authors.forename: Bicheng
authors.initials: B
authors.lastname: Yong
authors.forename: Pingxian
authors.initials: P
authors.lastname: Tan
authors.forename: Junqiang
authors.initials: J
authors.lastname: Yin
authors.forename: Changye
authors.initials: C
authors.lastname: Zou
authors.forename: Xianbiao
authors.initials: X
authors.lastname: Xie
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Gang
authors.initials: G
authors.lastname: Huang
authors.forename: Qianyong
authors.initials: Q
authors.lastname: Wang
authors.forename: Jingnan
authors.initials: J
authors.lastname: Shen
mesh_terms: D000293:Adolescent; D000328:Adult; D000970:Antineoplastic Agents / Q000009:adverse effects*; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012516:Osteosarcoma / Q000188:drug therapy* / Q000401:mortality; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies
chemical_list: D000970:Antineoplastic Agents