Researchers found a PET scan done six weeks after completing a combined treatment of radiation and chemotherapy reliably identified residual cancer and distant metastases or secondary tumors in patients with advanced-stage head and neck cancer. This result, researchers say, has a direct influence on health management decisions.
Twenty-six patients with stage III or stage IV head and neck cancer had a PET scan before and about six weeks after the end of the combined treatment of radiation and chemotherapy. Using PET, researchers in Switzerland correctly identified residual tumor tissue, distant metastases, or a second primary tumor in 10 patients. Five of those patients had no clinical evidence of these findings. The PET scan falsely identified cancer in one patient and failed to identify cancer in another. In the remaining 14 patients, the PET scan accurately showed no cancer or residual tumor tissue.
Researchers conclude PET can provide critical information in a noninvasive and timely manner. In addition, PET has the potential to identify patients who could benefit from salvage surgery very soon after completing therapy when the extent of the enduring cancer is limited and there is a better chance for a cure.