Sometimes it is best to let sleeping dogs be... however.
Regarding the statement that the rash is a good sign.....
Consider that the rash is actually very common, it occurs in 76-88% (10% severe) of the patients.
Clearly, SOMETHING is happening, the question is what is happening actually related to Erbitux being effective (i.e. inhibit growth of EGFR+ tumor cells) or is it an unrelated side effect which then since it almost universally happens is called "good". The rash occurs in places that have nothing to do with cancer and it would also occur in people that do not have cancer.

It is clear that Erbitux is effective under the right conditions, especially in combination with radiation. Thankfully, the really severe adverse effects are rare and most likely happen very quickly and generally during the first infusion.

M

http://packageinserts.bms.com/pi/pi_erbitux.pdf