TREATMENT OF HIGH-GRADE BONE SARCOMAS WITH NEOADJUVANT CHEMOTHERAPY -THE UTILITY OF SEQUENTIAL COLOR DOPPLER SONOGRAPHY IN PREDICTING HISTOPATHOLOGIC RESPONSE

OBJECTIVE, The purpose of this study was to use color Doppler flow ima ging to predict the response to preoperative chemotherapy in patients with Ewing's sarcoma or high-grade osteosarcomas early in treatment. S UBJECTS AND METHODS. Color Doppler flow imaging was done in 31 patient s before, during, and after chemotherapy. In each phase of treatment, semiquantitative changes in intratumoral blood flow, changes in maximu m intratumoral Doppler shifts, and changes in resistive indexes of art eries feeding limbs that contained tumors relative to contralateral no rmal arteries were compared with the histopathologic response, as eval uated on the resected specimens. RESULTS. Before chemotherapy, patholo gic flow was found in the extraosseous component of all but two patien ts. Resistive indexes in arteries that fed tumors were significantly l ower (p < .001) than the resistive indexes in the contralateral normal arteries. Histopathologic response could not be predicted on the basi s of the initial measurements of Doppler shifts and resistive indexes taken before or after the first cycle of chemotherapy. Histopathologic response could be predicted after the second cycle of chemotherapy. A fter the second cycle of chemotherapy, the resistive index in the arte ries that fed tumors increased in eight of nine good respondents but d id not change or decreased in eight of nine poor respondents (p = .03) . Lower intratumoral Doppler shifts were measured in six of 10 good re spondents but also in five of 13 poor respondents (p = .07). After the full course of chemotherapy, persistent lower resistive indexes were measured in the arteries that fed tumors in all poor respondents but o ne. Intratumoral flow and Doppler shifts further decreased in all good respondents but one. Changes in Doppler shifts (p = .001) and resisti ve indexes (p < .001) were statistically significant between good and poor respondents, irrespective of the tumor type studied. CONCLUSION. Decreased or unaltered resistive index in the arteries that feed tumor s in addition to persistent intratumoral flow and high-frequency Doppl er shifts after two cycles of chemotherapy suggest poor histologic res ponse to chemotherapy in osteosarcoma and Ewing's sarcoma. An increase d resistive index after two cycles is indicative of good response.