Slowly but surely some info is starting to emerge. I have good news and bad news (don't you hate it when people say that?) and there's still more to figure out, but here's the update as of today.
Good news: I got the results back from yesterday's MRI, and from what it could see, there is only one tiny (6mm) tumor in the right breast, nothing in the left breast, and no obvious enlargement of the lymph nodes (which if present might indicate that the cancer had spread beyond the one spot). That's all very reassuring and makes us hopeful that this was caught early enough to be "only" stage 1 (though final staging is not complete until after surgery).
Bad news: I went to UCSF today for a consult with a radiation oncologist recommended by my surgeon. She told me flat out that given my previous 9 weeks of radiation treatments for the Hodgkin's Disease 23 years ago, she would recommend against any further radiation treatments of any kind for me. That means a lumpectomy is right out, since in order to make that successful, the lumpectomy option always includes radiation afterwards. I had a feeling that was going to be her recommendation so I was braced for that, but I wasn't really expecting what followed (though in hindsight duh, I totally should have). She then also said that she felt that the previous radiation treatments had contributed to this occurrence of breast cancer, and since both breasts were part of the previous radiation field, there was approximately a 20% higher risk that the cancer could occur separately again on the left side at some point in the future. That's a risk that would be added to all the other risks I already have (the same risks which clearly tipped me over into the "bad gamble" range this time). So while she didn't make an explicit recommendation (that's for the surgeon to finalize), it does now sound like if my top priority is to not have another occurrence of cancer (which it totally is), it would be a smart idea to opt for a double mastectomy.
Needless to say I feel very unhappy about the idea of undergoing major surgery that culminates in me losing both breasts. At the moment I'm utterly floored by that scenario, and trying to process a lot of grief and fear--and I have to say, my attitude will NOT be helped (yet) by optimistic look-on-the-bright-side chatter about how great it will be to have reconstructed perky fabulous any-size-and-shape I want breasts. They will be fake and not mine and I hate being forced into this change, regardless of any silver lining that might eventually shine through.
More info to come as this week develops. I am sure we will be talking about whether or not follow up chemo/hormonal treatments will be necessary, and I'm sure we will be talking about what kind of surgery would provide the most successful reconstruction option(s). I know it could be worse (it can always be worse) but it feels pretty shitty right now.