Cell kinetics and tumor regression during radiotherapy in head and neck squamous‐cell carcinomas

Role of Computed Tomography Imaging in Predicting Response of Nasopharyngeal Carcinoma to Definitive Radiation Therapy

“…Prognostic value of radiosensitivity associated with better local control has been suggested for some head and neck cancers excluding NPC 3–6 . Regression of tumor during or shortly after curative radiation therapy has been suggested to provide an in vivo indication of tumor radiosensitivity 6,7 .…”

“…Prognostic value of radiosensitivity associated with better local control has been suggested for some head and neck cancers excluding NPC 3–6 . Regression of tumor during or shortly after curative radiation therapy has been suggested to provide an in vivo indication of tumor radiosensitivity 6,7 . However, the volume by which a tumor changes after irradiation depends on multiple factors such as the percentage of cancer cells killed, the mode of cell death, the architecture of the tumor, the amount of radiation induced surrounding tissue changes, including inflammation and/or necrosis, and the efficiency of clearance of dead cells from the diseased area.…”

“…Local control is prognostically important in nasopharyngeal cancer 2 ; however, despite aggressive local treatment with radiotherapy, more than 30% of patients with NPC still died of local failure 3,4 . Although the most reliable factor for predicting outcome from definitive radiotherapy is the pretreatment cancer stage, 5 some data have suggested that regression of tumor during or shortly after the course of radiation is an in vivo indication of tumor radiosensitivity of certain head and neck cancers and may also have prognostic significance 6,7 …”