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Intraarterial infusion chemotherapy for head and neck cancers: evaluation of tumor perfusion with intraarterial CT during carotid arteriography.

PURPOSE
To evaluate drug distribution in carcinomas of the head and neck region with CT during intraarterial contrast-material injection for superselective intraarterial infusion of anti-cancer agents, and to evaluate perfusion in the carcinomas with intraarterial dynamic CT, using a combined CT and angiography system.


MATERIALS AND METHODS
Twenty-three consecutive patients underwent conventional angiography as well as intraarterial injection CT using a combined CT and angiography system. Contrast material enhancement on intraarterial CT images was evaluated qualitatively and quantitatively with the following parameters: enhanced pattern, delineation and extent of tumor, peak CT value, peak time, maximum inclination of wash-in and washout, and transfer index (k) using a Patlak plot method. After the feeding vessels had been identified by enhancement of the tumor on CT of the selected vessel, relatively low-dose cisplatin was injected through the microcatheter placed in each artery depending on tumor location. Histopathologic effects were evaluated after surgery and compared with CT findings.


RESULTS
In the qualitative evaluation, tumors showed early, strong enhancement as well as rapid washout compared with the adjacent normal tissues, and dynamic CT was useful for evaluation of the extent of the tumor. When multiple feeders existed, the dose of cisplatin for each feeder could be determined by the percentage of tumor enhanced with CT on each vascular injection. The mean values of quantitative parameters, however, were not significantly different between the good and poor response groups.


CONCLUSION
Intraarterial CT was useful for evaluation of the arterial supply and drug distribution of the tumor. However, quantitative data did not provide additional information for prediction of the treatment effect. This might indicate that the effectiveness of intraarterial chemotherapy is not directly related to the perfusion of head and neck cancers.