Hmm. Cotton swabs in mouth? Never heard of that one. Tried to get a cell sample for mom when it was thought she had ascites fluid in abdomen. By the time of the procedure, the ultrasound tech didn't feel it could be done safely at the time due to decreased fluid. The big hurdle to my mind is access to an adequate sample. I think the folks Nagourney et al work with in CA are more aggressive about getting tissues. If you can't get enough sample for the other tests, a smaller amount might yield results via ChemoFX which can "grow" the samples, the negative there being delays and potentially less accurate results. GDpawel will chime in shortly I suspect. More on various chemosensitivity tests
here