Initial treatment with chemotherapyandradiation will often reduce tumor size. However prolonged use ofchemotherapyand radiation do not result in more tumor destruction.

The results showed that UV radiation mainly led to crystal destruction and molecular degradation on the surface and recrystallization on the interior part of the sample.

If some of these specialized cells escaped destruction by chemotherapy or radiation, the tumor would be able to recur quickly, often in a form resistant to chemotherapy.