What’s different in the stage 0 melanoma patient than the stage 1 patient such that 10-year survival rate is higher?
The earlier that melanoma is caught (or staged), the higher the survival rate when projected 5-10 years out. So for stage 0 melanoma, the 10-year survival rate is about 99 percent.
For stage 1A melanoma the 10-year survival rate is 95 percent; for stage 1B it’s 86 percent.
What’s going on here? All of these tumors are “thin” and not penetrated into the dermis layer of the skin.
“My own sense of this is as follows,” begins Judith Hellman, MD, Associate Clinical Professor of Dermatology, Mt. Sinai Hospital, NY, who has a private practice in Manhattan.
‘When a melanoma is treated, we follow guidelines in the treatment, and excise some extra skin around the melanoma according to the stage it is.”
That extra-excised skin is normal, as a precaution that in case any tumor cells have strayed, they too get removed.
“In theory, this should be a good measure to know that there will be no mets [spread],” continues Dr. Hellman.
“However, sometimes random melanoma cells can escape the confines of a lesion and the margins of a surgical excision.”
This is more likely to be the case with a deeper (though still confined) tumor. Stage 0 isn’t as deep as stage 1A isn’t as deep as stage 1B, and so on.
Melanoma stages. Cancer Research UK
“These cells can certainly survive, multiply and find their way to other parts of the body,” says Dr. Hellman.
“Nothing in nature is 100%, so there can always be some undetected cells that can make their own way and grow at a different site.
“I think this is pretty rare in an in situ lesion [the most superficial form of melanoma] or one that hasn’t penetrated very deep.
“It’s also possible that a second, unrelated primary melanoma pops up at some other place.
“We know that anyone with a primary skin cancer is more likely to develop more of the same or other type of skin cancer.
“So I think, ultimately, some cells fly under the radar of the immune system, which polices irregular cells in the body, and manage to develop into a lesion.”
