Do you consider prior use of cisplatin for a previously diagnosed cancer a contraindication for its use as radiosensitizer in a new head & neck cancer?  

No. Platinum remains the standard of care as a radiation (RT) sensitizer for locally advanced head and neck cancers whether treatment first-line or in the recurrent setting. To date, there is no data to support an alternative radiation sensitizer even if disease recurs and re-irradiation is consider...