Colour Doppler ultrasound predicts chemotherapy response, but not survival in paediatric osteosarcoma

Background : Histological response to chemotherapy is an important prognostic factor in osteosarcoma, influencing therapeutic considerations. It would be advantageous to be able to assess chemotherapy response, and predict survival, prior to tumour resection. Colour Doppler US (CDUS) is non-invasive, non-demanding for the patient, and easy to plan. This makes the method especially suitable for children, who comprise the majority of patients. Objective : To establish the value of CDUS for pre-operative prediction of chemotherapy response and survival, using widely available US equipment. Materials and methods : CDUS was performed in 21 consecutive patients before and after chemotherapy. Peak systolic velocity (PSV) in the soft-tissue component of the tumour and quotient of resistive index (QRI) of the feeding artery and contralateral control were calculated. A pathologist, unaware of CDUS results, assessed the response to chemotherapy after resection. Results : QRI change after chemotherapy was significantly higher in histological responders. No correlation of QRI change with survival was found. There was no significant difference in PSV change comparing any subgroup. CDUS appeared useful in predicting chemotherapy response (sensitivity 83%, specificity 86%), especially for negative response (predictive value 92%). Survival could not be predicted accurately. Conclusions : CDUS can predict chemotherapy response, but not survival. The method could be useful in planning treatment prior to definitive surgery.