I had never heard of ductal carcinoma in situ before I was diagnosed with it. Nor did I have a clue that breast cancer could be classified as stage 0; I only thought it came in stages 1 through 4. And I’m far from alone; most people I talked to had never heard of it either, including a couple of experienced healthcare PR pros.

This point was brought home to me last weekend, when I did a book signing at “Bodies: The Exhibition” in Omaha. The most interesting moment was when an older, upper-middle-class couple came up to me. The man spoke; the woman stood mutely at his side as wives of that generation are likely to do.

“We were just wondering about your title,” he said. I explained that From Zero to Mastectomy was a play on from zero to 60, and before I could mention the subtitle’s reference to stage 0 cancer, he said, “Well, we were just wondering where that came from because there is no such thing as stage 0.” He looked at me and waited, with a look of absolute confidence on his face.

I looked over at his wife; no help was forthcoming there. She had the frozen smile of someone who’d been through this hundreds of times on who knows how many topics. So I just said, “I never heard of it either until I was diagnosed with it.” He didn’t respond; he just turned away and off they walked.

I don’t know what his deal was; retired professor? Doctor? Professional hair-splitter? I do know that DCIS is noninvasive because it’s confined to the milk ducts. Some call it precancerous. That’s the good news. The bad news is that it can become invasive if not treated, and treatment is the same as for invasive cancers. DCIS has varying degrees of aggressiveness, with some  types more likely to become invasive. You need to go over your specific circumstance with your doctor, weigh your risk tolerance, and make the decision that’s right for you.

As to whether it’s “real” cancer, my oncologist used that word one day, after I had become comfortable with him and with my decision to get a mastectomy. He told me I’d need to come back every six months for regular checkups, and said it would be every three months if I had “real” cancer.

He wasn’t being snarky, so I pounced and said, “It’s close enough! Someone sign me up for the fake mastectomy!” We laughed about it, and that’s become our running joke.

So maybe the old man was right. If you believe cancer by definition is invasive, then perhaps stage 0 is an oxymoron. But while the cancer may be “fake,” the treatment is very real. There’s an old saying, “Close only counts in horseshoes and hand grenades.” Perhaps we should add DCIS to that list.

Jackie Fox is the author of From Zero to Mastectomy: What I Learned And You Need to Know About Stage 0 Breast Cancer, and blogs at Dispatch From Second Base.

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