A clinical study of individual chemotherapy for osteosarcoma and chemosensitivity-related gene

LONG Zuo-yao; LU Ya-jie; LI Ming-hui; XIAO Xin; WANG Zhen

doi:10.3969/j.issn.2095-252X.2019.03.015

Abstract：Objective To explore expressions and mutations of chemosensitivity-related genes, and to discuss the correlation between gene and clinical outcomes. Methods This study selected 38 osteosarcoma patients from 2011 to 2017. The mean age was 16.32 years. There were 18 males and 20 females. Location: 25 patients in the distal femur, 9 patients in the proximal tibia, 2 patients in the distal humerus, 1 patient in the hip and 1 patient in the distal clavicle.All of them were common osteosarcoma. Expressions and mutations of chemosensitivity-related genes were detected via real time PCR and DNA sequencing, including ifosfamide-related gene ( CYP2 C9*3), platinum-related genes ( ERCC1, BRCA1, XRCC1, GSTP1, MRP2), and doxorubicin-related genes ( TOP2 A, ABCB1, GSTM1, GSTT1).Chemosensitivity was evaluated by a systematical analysis of the results of PCR and DNA sequencing. All patients underwent the same chemotherapy regimen including ifosfamide, platinum and doxorubicin. Clinical outcomes were evaluated by pain, tumor size, tumor boundaries and calcification. Results Neoadjuvant chemotherapy effective rate was 63.2％ ( 24/38). Sensitive rate: ifosfamide 89.5％ ( 34/38); platinum 81.6％ ( 31/38); doxorubicin 57.9％ ( 22/38). Gene sensitivity: sensitive to one drug, effective rate 0％ ( 0/3); sensitive to two or three drugs, effective rate 70％ ( 14/20); sensitive to three drugs, effective rate 66.7％ ( 10/15). Conclusions Patients who are sensitive to multiple drugs have better chemotherapy efficiency than to only one drug. More research is needed on the adjustment of chemotherapy regimen of patients with low sensitivity. Large-scale samples are recommended to enhance the reliability of the conclusion.