Here are the statistics from the American Cancer Society:
In the United States, vulvar cancer accounts for nearly 6% of cancers of the female reproductive organs and 0.7% of all cancers in women. In the United States, women have a 1 in 333 chance of developing vulvar cancer at some point during their life ( an d apparently more common in younger women).
The American Cancer Society's estimates for vulvar cancer in the United States for 2018 are:
About 6,190 cancers of the vulva will be diagnosed
About 1,200 women will die of this cancer.
The American Cancer Society estimates for penile cancer in the United States for 2018 are:
About 2,320 new cases of penile cancer diagnosed
About 380 deaths from penile cancer
For statistics related to survival, see Survival Rates for Penile Cancer.
Penile cancer is rare in North America and Europe. It is diagnosed in less than 1 man in 100,000 each year and accounts for less than 1% of cancers in men in the United States.
Cancer of the genitals appears to be part of the human condition, but definitely on the more rare side of things. When pro-circumcision propagandists use penile cancer prevention (predominantly in elderly men) as a reason to circumcise baby boys, it is a fear tactic and predominantly uses to scare parents into circumcising their boys.
At least in the case for women we practice ethical medicine and don't recommend female circumcision to prevent cancer of the vulva.