What would cause intermittent burning pain in the flank and or thigh. worried i have kidney cancer at 37. ?

Need to examine: It is not feasible to provide a meaningful opinion without additional history, physical examination and may be some tests. What you described is not a usual feature of kidney cancer. It would be prudent to see your doctor. Visit this site for info on this topic: https://www.mayoclinic.org/diseases-conditions/kidney-cancer/symptoms-causes/syc-20352664?p=1&pos=1 Wish you good health!

Many,pain sources: While you could have a cancer, most people do not have pain as the symptom which brings it to,their attention. I regret that you have a concern regarding thus disease and perhaps you should,discuss that with your doc. Flank/thigh pain could come from muscle fatigue or cramps, local trauma, urinary tract infection/stone, skin irritation or disease, hip or spine degenerative disease. Good luck