Nasopharyngeal Cancer Patient Increase Subcutaneous Adipose Tissue during Radiotherapy Decrease Local Recurrent Rate

Nasopharyngeal cancer (NPC) patients lost their body weight more than 5% has better disease-free survival; this phenomenon cannot be found in oral cavity or pharyngolaryngeal cancer. Our hypothesis is that body weight lost during radiotherapy with better survival in NPC patients is due to the effect of body fat change. At the thoracic vertebra T3 level, the subcutaneous adipose tissue area increase at the time around 3 weeks after the start of radiotherapy treatment (p=0.003). This result also cannot be found neither in oral cavity nor pharyngolaryngeal cancer. The difference between oral cavity cancer/pharyngolaryngeal cancer and NPC is almost all the NPC samples contain Epstein-Barr virus (EBV). Fatty acid synthase (FASN) is induced after the EBV moving into the lytic cycle. After the lysis of the EBV-contained NPC cancer cells, the FASN might circulate in the body and might induce lipogenesis during the course of radiotherapy. The differences of body fat between the first and the second time of simulation during radiotherapy can be measured by Housefield Unit. The more the adipose tissue, the more the leptin secreted by the fat, then it might cause the NPC patients losing their appetite which further lost their body weight at the end of the course of radiotherapy. This research is tried to prove the body fat change in patients with NPC during radiotherapy is related to the local recurrence. We hope to find out the pattern of body fat change that can predict the local recurrent rate.

Project ID:PC10207-0420
External Project ID:NSC102-2314-B182-057