Colon Polyps and Probability

Most colon polyps do not turn into cancer, but nearly all color cancers derive from colon polyps "gone bad".

From the Colon Cancer Foundation (which we'll assume is a reputable site for deriving statistics):

Probability 1:
"Adenomatous polyps or adenomas—These polyps can become cancerous, and they account for approximately 75% of all colon polyps."

P1 = .75

Probability 2:
"The larger a polyp grows, the more likely it is to become cancerous. Once a polyp reaches approximately one inch in size, the risk of cancer is in excess of 20%."

2.5cm = .98" (roughly one inch)

Therefore,

P2 = .2

Probability of two independent events:

P1|2 = P1 * P2 = .75 * .2

Probability that I have a adenoma that is cancerous: .15 or 15%

I'm really not liking the odds. The doctor said that he felt we'd caught it in time, but according to the sites I've read, it's not easy to visually determine if a polyp is an adenoma by visual observation; it really does require microscopic examination on the cellular level.

I have a follow up with the GI on the 22nd. I'm afraid gime is going to drag until then. I wonder if there are implications for being able to do an IVF cycle, with the exposure to high levels of estrogens and all?