Let me get this right: apparently the book describes that implants are "a big decision that has to be thought about very, very carefully". She briefly discusses the risks of implants including pain, degrading of the implants, difficulty breastfeeding, and surgical complications.
But a double mastectomy for a young girl who might not be entirely comfortable with the idea of growing breasts (which is not at all abnormal at that age, especially as they are often uncomfortable and painful due to hormonal changes and growth, often increase one being subject to the "male gaze", can also increase teasing, may interfere with sports at times (and especially are painful when one gets smacked in the chest), mean uncomfortable bras for many (since many women still wear wrong bra size), and so on) is just discussed in such a passing manner as an option that might be suited for some?
I have had double mastectomies for preventative reasons (hereditary breast cancer risk). Risks of such surgery and mastectomies - which were well researched and well explained - include negative reactions to the anesthesia - including death, pain - including for some chronic pain, infection, tissue/nipple necrosis, bleeding, significant scarring, possible lymphedema (as some nodes always get caught up in the removal of tissue) and yeah, not just a risk of loss of breastfeeding, but absolutely no breastfeeding. Also other more minor inconveniences like how the hollow left by the absence of your breast tissue in your armpit makes it hard to shave your armpits (if you desire) properly or without nicking yourself). Then there is that recovery period where you can't lift anything for a while, anything above your head for a while longer, and get to walk around with drains for a while, emptying them at least twice a day.
Breasts are body parts. Mastectomies are an amputation of those body parts. They may not have bones and so on, but dismissing them as so easily removed if one is not comfortable with them- to pre-pubescent/pubescent girls - is horrific. I know for even women diagnosed with breast cancer who are recommended to get mastectomies as part of their treatment, the decision can be a difficult one, even if they don't always "love" their breasts.
I have a hard time buying a version of "The Penis Book" would so casually portray removing one's penis or testicles. After all, some pre-pubescent/pubescent boys might not want their penis either!
I am sorry, this just really angers me. Especially as an adult woman with a significant family history of hereditary breast cancer who had to navigate through a complicated system to get the mastectomies that were highly recommended to me by high risk clinicians and geneticists I consulted with (and my sister is going through same thing now). And I am fine with that, as frustrating as it could be, as it makes sense that everyone along the line wanted to be sure I was sure. I often feel reading these kind of things that I should have just walked in to any local doctor's office and said I identify as a male instead; I could have probably saved 1.5-2 years of genetic consults, genetic testing, referrals to surgeons, then to plastic surgeons, and so on.