Characterization of localized osteosarcoma of the extremity in children, adolescents, and young adults from a single institution in South Texas.
BACKGROUND
Osteosarcoma is the most common bone malignancy in children, adolescents, and young adults. Most study cohorts have 10% to 15% Hispanic patients that encompass many different Hispanic backgrounds. This study characterizes the effect of mainly Mexican American ethnicity on the outcome of children, adolescents, and young adults with osteosarcoma.


METHODS
A retrospective analysis of demographics, tumor characteristics, response to treatment, and survival outcome of all localized osteosarcoma of the extremity patients below 30 years of age was performed. A Kaplan-Meier estimates with log-rank tests and Cox proportional hazard regression models were used.


RESULTS
Fifty patients (median age, 15; range, 2 to 28 y) with localized high-grade osteosarcoma of the extremity were diagnosed between January 2000 and December 2010. The cohort was 70% Mexican Americans. With a median follow-up of 39 months (range, 5 to 142 mo), patients had a 5-year overall survival and event-free survival of 65% and 48%, respectively. We observed a significantly decreased 5-year event-free survival in patients diagnosed before age 12 relative to patients diagnosed between ages 12 and 29 (11% vs. 57%, P<0.001). We also found that tumor necrosis was not predictive of outcome in our patients.


CONCLUSIONS
The preadolescent patients of predominately Mexican American ethnicity had an increased rate of relapse when compared with previous studies. Tumor necrosis is not directly predictive of outcome in this population.
*Greehey Children's Cancer Research Institute Departments of †Pediatrics, Division of Hematology and Oncology §Epidemiology and Biostatistics ∥Orthopedics ¶Pathology ‡School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX.
Aaron J
AJ
Sugalski
Alisha
A
Jiwani
Norma S
NS
Ketchum
John
J
Cornell
Ronald
R
Williams
Josefine
J
Heim-Hall
Jaclyn Y
JY
Hung
Anne-Marie
AM
Langevin
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001859:Bone Neoplasms / Q000208:ethnology* / Q000401:mortality* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D017058:Mexican Americans / Q000706:statistics & numerical data*; D015999:Multivariate Analysis; D009336:Necrosis / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000208:ethnology / Q000401:mortality / Q000473:pathology; D012516:Osteosarcoma / Q000208:ethnology* / Q000401:mortality* / Q000473:pathology; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D013781:Texas / Q000453:epidemiology; D055815:Young Adult