I recently spoke to a hematologist-oncologist (a hem-onc) who specializes in melanoma and is very familiar with PV-10, Yervoy (ipilimumab) and Zelboraf (Vemurafenib) clinicals trials, and [obviously] the approvals of the Yervoy and Zelboraf. Let's call him a Key Opinion Leader, whose perspectives appears to be objective or reasonably objective (or, perhaps, not too subjective).
A snippet of my conversation with him: Given his intimacy with these treatments, I wanted to know how clinicians (at large, and not just him) would choose from a myriad of therapies to treat a cancer-ridden patient (any kind of cancer, not just MM). He characterized cancer in two groups, MM, which is very rare, and other cancers like breast, prostate, etc., which are relatively more common. He felt that, with only 8,000 cases of Stage 4 MM a year, that these (and many or most, if not all, Stage III) patients very likely would be referred to a melanoma specialist like him (as opposed to other more common forms of cancer, where patients would remain with their "regular" oncologists).
He said while there were guidelines as how to treat people, the treatment ultimately strategy and decision remained with the treating physician. He used the example of a patient with MM and the BRAF gene. A patient might come in, and he might determine he or she had said gene. His approach could be that even though he knew that they had this gene, and based on their personal situation (e.g., at this time, such a patient might have regional disease that was amenable to injection), he might first use PV-10, knowing that if it failed or was not as effective, he could always reach back into his toolkit for Zelboraf.