M&M

Some numbers to consider: 40% and 3%. They estimate the respective likelihood of morbidity & mortality from the Whipple procedure. In surgical circles, M&M is the acronym for the Scylla & Charybdis of operative complications: serious side effects and death.

And then, two more numbers: 100% or 0%. They represent the binary math of whether my surgery will prove worthwhile. Either it will produce the desired outcome (the prevention of metastases, prolonging my life while sustaining its quality) or it will not. In some ways, while the operation itself is quite literally out of my hands, I am the ultimate arbiter of whether it will be deemed beneficial in the long run. In my case, the Whipple is a prophylactic maneuver to avoid tumor dissemination, but the polysyllables of pancreaticoduodenectomy make no secret that it is also a radical resection of some major abdominal organs. My surgeon, remarkably skilled as he is, cannot rule out the possibility that my digestion will never normalize, that I could incur delayed gastric emptying, a bile leak, or a fistula through the almost Cubist rearrangement of my upper GI tract.

I have been given percentages to contemplate about all these dire possibilities. I have done my best to process them cerebrally, but in the end, the decision to go to the OR is -- warning: incoming pun! -- based on a gut feeling. I can sense, viscerally more than intellectually, that this is the right thing to do at this time.

And yet the cancer doctor in me cannot entirely resist the allure of less empiric prognostication. It's my specialty's lifeblood to cite numbers to our patients. That's how we've framed the calculus of difficult decision-making. We try to show them that the risk of any chemo is outweighed by its potential benefits. Expressed as a fraction, we trust that the risk/benefit ratio won't be top-heavy.

The medical oncologist's mind is, at its most objective, a repository of numbers -- a 37% chance of grade 3 emesis with a certain combination regimen vs. only a 13% chance when deploying a single agent -- whereas the patient is understandably less rational. Their choices often stem from their amygdala, their fear center, more than any other part of their brain. And so, for them, it becomes an accountancy of threats. In the ledger of horrors, their natural revulsion to poison has to be superseded by their terror of an unopposed cancer. Every patient's balance sheet looks different. For some, no chance is too slim to lose its seductiveness, still enticing even when hope for a positive outcome looks waif-thin.

Chemo is a hard sell, perhaps the hardest. I sometimes envy the pharmaceutical companies, who can advertise their drugs with the most artfully composed distractions. Since they need to make their products appealing while also being legally obligated to disclose side effects, they run a breathless audio description of fearsome toxicities with deliberate incongruity beneath video of smiling attractive couples on adventurous vacations. The clinic rooms where I sit with patients as they weigh their choices are not nearly as diverting. But if I'm honest, I'm guilty of the same misdirection, rushing through the litany of potential outcomes (and similarly likely to mention death as fleetingly as possible). Then I advise my patients to sign on the dotted line with the assurance that, in my professional medical opinion, the good likely exceeds the bad. For all the talk of darkness, the future looks bright.
 
How differently things can seem at our next encounter, ideally meeting again during a scheduled office visit but sometimes in the ER or, worst of all, in the ICU. That laundry list of maybes with which I deluged them at our prior appointment has now been narrowed, clarified into a present reality of pernicious consequences. A squall has intruded on a sunny forecast, and it's time for the weatherman to accept blame.

As an oncologist, you feel queasy at the outset of a therapeutic relationship that you might be telling half-truths, and the insoluble problem is you can't identify which half. You trained as a scientist but practice as an intermittent fabulist. I can't discern at the start who's being suckered into a bad deal. Only time will tell how one patient will do versus another, dramatic irony illuminating who absolutely required a perilous intervention and declined it, versus someone who accepted it needlessly and was harmed as a result. “Individual results will vary" is the catch-all clause, the escape hatch from incorrect projections.

The famous quote from Mark Twain places our mathematical sleight-of-hand deliberately last in the unholy trinity of "lies, damned lies, and statistics". I've also heard a wry modern update that "statistics mean never having to say you're certain". It is karmic, then, that the doctor who bombards his patients with untrustworthy numbers would be presented with his own tenuous risk assessment and forced to commit.

M&M is such an inextricable part of medicine that we have entire conferences devoted to the near-forensic reconstruction of cases gone awry, either on the hospital ward or in the operating room, that we might learn from errors in judgment or flag sentinel events warning us of systemic dysfunction in care delivery.

I go to the OR myself with a head full of numbers but a faithful heart. I have absolute confidence in my surgeon and my peri-operative team. Even if I were to be presented at a future M&M conference, I will not look back in anger or with regret at my decision now.

Mark Lewis3 Comments