I’m in the early stages of work on a paper that’s partly about moral and epistemological issues involved in changes in medical practice. In particular my co-author and I are interested in the relationship between the “therapeutic obligation”– physicians’ obligation to provide patients with the most effective treatment, ceteris paribus— and levels of uncertainty about what the most effective treatment is, in particular in cases of new or experimental treatments. (One frequently-discussed version of this problem comes up in the ethics of randomized trials. How could patients be permitted to enroll or continue in RCTs given that, over time, justification for preferring one arm of the trial over another would grow stronger without being sufficient to justify stopping the trial?)

Anyway, reading up on this stuff took me on a little detour through the history of breast cancer treatment. I was going to write up a big long tedious post on this, then I remembered I’m not a historian. ZING!

Mildly interesting, some graphic drawings. Most of this is from Cotlar, et al., “History of surgery for breast cancer: radical to the sublime,” Current Surgery 60 (3), 2003.

Some fascinating facts about breast cancer treatment: breast tumors were described as early as the Edwin Smith papyrus. The earliest treatment of choice was cauterization, though Roman physicians seemed to favor excision. Surgery became more popular during the Renaissance with the invention of several devices for the rapid removal of the breast.

The mastectomy instrument of Gerard Tabor, 1721:

In 1882 the American surgeon William Halsted first performed what would become known as the Halsted Mastectomy, which involves removal of the entire breast, area lymphatic tissue, and the pectoralis muscle. Halsted achieved a 5-year cure rate of 40% through a number of innovations: his aggressive approach to tissue removal, his use of the antiseptic techniques introduced by Joseph Lister, and his introduction of the use of rubber gloves. (Apparently his nurse, later wife, developed skin irritation from contact with the sterilizing agent, so Halsted asked Goodyear to develop some gloves, which were first used in 1889.)

Below: Halsted incision and final cut.

Surprisingly the Halsted is not the most aggressive technique: surgeons in the 50s experimented with “extended radical” or “super-radical” mastectomies but found no increase in survival rates.

What’s a little freaky about this is that between 1910-1964 about 90% of US surgeries for breast cancer were Halsted mastectomies, later augmented by radiation treatment. The Halsted was abandoned in the 70s after randomized trials found that the Halsted offered no improvement in survival rates over the less invasive modified radical mastectomy.

One halfway interesting question– an empirical question, my friends– is how we’d walk back from a standardized but seriously invasive technique to something less extreme, given that our survival rate is pretty good. (Looking at the drawings emphasizes that survival is not the whole of success, I grant.) I wonder about what sort of confidence (and what sort of evidence) the pioneers of less invasive techniques had that their procedures would be at least as successful.