Treat/replace upper tract?Given TLT's compounds and sensitivity to various light frequencies, and if the source of the recurrence can be established as the upper tract, what are the possibilities if TLT knows that going into the next trial/re-treatment? Can the upper tract be instilled with the sensitizer and exposed to light so it can be included in the treatment? Can the upper tract be replaced completely, some sort of "conduit diversion" so that it can no longer harbor cancer? I'm not a doctor (obviously), but it seems like if x-rays have the potential to eliminate GBM using the same sensitizer technology, they should be able to treat the upper tract somehow. Also, if TLT is treating the bladder for bladder cancer, how far 'upstream' from the bladder is the treatment responsible for treating? If the cancer is also present in the upper tract or kidneys, is TLT's PDT treatment responsible for treating it? I doubt this was an issue for Keytruda.