Comment by sxg | Hacker News Reader

Comment by sxg | Hacker News Reader

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The other commenter is pointing out the flaw in your argument. You're claiming that Australians are less likely to see stage IV cancer than Americans due to a worse healthcare system in America. As the other commenter states, that's a very believable argument that fits the narrative about America's healthcare system. However, the data doesn't support that claim. If Australians truly see fewer cases of stage IV cancer because of a better healthcare system, then we should expect to see higher 5-year survival rates for those cancers in Australia. As the other commenter brought up, 5-year survival rates are higher in America than Australia for the most common cancers. So it's unlikely that your original argument is correct.

Sure, America's healthcare system is deeply flawed, but it's important to attack it on fair grounds. We can't solve a systemic issue by raising claims and arguments that aren't supported by evidence.

EDIT: Furthermore, identifying early stage cancer is an extremely problematic and difficult field regardless of healthcare system and country. In America, we currently screen asymptomatic healthy adults for breast cancer and colon cancer. We screen people with a smoking history for lung cancer. However, the benefits to overall mortality of these cancer screening tests is controversial.

While in theory identifying stage I cancer should result in improved overall mortality, the data doesn't clearly show that. Take a look at length-time bias (https://en.wikipedia.org/wiki/Length_time_bias). It's possible that a substantial portion of the cancer screening that's done in America (and the stage I cancers found in Australia) selectively identify indolent cancers that are unlikely to be harmful to patients.

> You're claiming that Australians are less likely to see stage IV cancer than Americans due to a worse healthcare system in America

I'm claiming that Australian citizens are more likely to bring cancer to their provider when it's still at stage 1, because the citizens do not risk bankruptcy when seeking diagnosis and treatment, resulting in treatment of cancers beginning prior to their reaching stage 4.

This would, if true, create a scenario where:

In Australia, the few stage 4 cancers seen are the cancers that failed treatment at stage 1, stage 2, and stage 3; they are extremely likely to be fatal, as they've already failed essentially every treatment available.

But in United States, the stage 1-2-3 "this is treatable" filtering out isn't occurring, because patients with cancer are waiting for age 65 to seek diagnosis, and so our stage 4 treatment success rate is higher because we didn't treat the treatable cancers earlier in the stages.

Do the above comparisons of AU vs US 'stage 4 survival rates' take into account the successful treatments at stages 1-3 that would presumably be occurring in AU? Do they take into account the incidences of 'this would have been treatable if diagnosed in stages 1-3' that are presumably occuring in US?

EDIT: Do they hold true for each individual type of cancer? Do they hold true when normalized for spending on a given type of cancer as a percentage of all cancer spending?

I'm aware that these are not easy things to compare or assess, and I understand that it's preferable to some to make no statement at all rather than make an approximation that doesn't hold up to a full-power statistical analysis. If someone does know of such a thesis, I suppose my most compact question would be:

"For each type of cancer: Does the Australian health care system tend to diagnose earlier than the United States health care system, provide care at a higher or lower total cost of treatment, with a higher or lower rate of success?"

> I'm claiming that Australian citizens are more likely to bring cancer to their provider when it's still at stage 1, because the citizens do not risk bankruptcy when seeking diagnosis and treatment, resulting in successful treatment of cancers prior to their reaching stage 4.

I understand your argument: you're saying that by treating stage 1–3 patients early on, the stage 4 patients will have a shorter survival. But in the US, stage 4 patients also include many patients that would have been stage 1–3 in a different country, and because these cancers may not be quite as aggressive as the other stage 4 cancers, the 5-year survival will be higher. I'm on board with this part of your argument.

The part that doesn't hold up is patients regularly coming in to their doctors with symptomatic early stage cancer. In early stages, many cancers are completely asymptomatic. Even when we screen completely asymptomatic patients for early stage cancer in the US, we don't actually see clear cut overall mortality benefits. So how is it that these Australians are presenting to their doctors so early on with cancer symptoms?

EDIT: The holy grail of cancer screening has three features:

- Identifies dangerous cancers shortly after they form

- Perfectly separates cancer from non-cancer

- Patients live longer

Medical science itself (regardless of healthcare system and country) can't reliably meet the above three goals. So I'm skeptical that patients having easy access to medical care like in Australia would result in improved cancer survival.

Perhaps Australians present to their doctors early for all symptoms, and it is the doctors who diagnose cancer? I can't speak for everyone in Australia but for me, if I am sick I have to see a doctor in order to get 'sick leave'. I have unlimited paid sick leave provided a doctor has recommended it. It also doesn't cost me anything to see a doctor or get any kind of test or treatment/surgery done - it is all covered by work.

Sure, I'm confident that Australians wouldn't hesitate to see their doctors given the low barrier to access. But the real question is how does any doctor in any country diagnose an early stage cancer?

This isn't a trivial problem. These patients are often asymptomatic, and objective physical exam findings are not easy to elicit or entirely non-existent. At this point, the only thing a doctor can do is screen every patient coming through the door for cancer via CT, MR, mammography, colonoscopy, etc., but this doesn't translate into clear cut clinically meaningful benefits that helps patients live longer. You often end up irradiating non-cancer patients and creating new cancers, or you selectively diagnose non-aggressive cancers (length-time bias) and unnecessarily put patients through surgery, chemotherapy, and radiation (i.e. over-treatment). Some fraction of these patients then go on to live shorter lives as a result of the over-treatment. This particular issue we're discussing is more of a medical science problem than a healthcare system problem.

Anecdote from med school: on my surgery rotation, I had a ~70 year-old patient recently diagnosed with early stage colon cancer on a screening colonoscopy. He had undergone chemotherapy and was now about to have the cancerous part of his colon removed. Surgery was a success, and the patient recovered in the hospital for a few days before we sent him home. The day after he goes home, we found out he died from a massive pulmonary embolism, likely a post-operative complication from surgery.

Alternatively, had this patient not had a screening colonoscopy, we never would have found his early stage cancer. Based on his cancer stage, he likely would've lived another 10–15 years without treatment (age ~85-90). Instead, our interventions killed him a few months after diagnosis.

Is there some analysis that goes into deciding to operate on someone of advanced age? The records of all births, deaths, and surgeries are known. Isn't it possible to compute the life expectancy of someone with or without surgery and simply select the best outcome? What benefit does surgery have if someone is likely to live to 85-90 without it?

Generally, these guidelines do exist, but they're made on a case-by-case basis by individual research groups. So there are parts of medicine where we have great research and other parts where we don't know much. In the US, the USPSTF consolidates the latest research into national recommendations (https://www.uspreventiveservicestaskforce.org/uspstf/recomme...). There are additional organizations like the American Cancer Society (https://www.cancer.org/healthy/find-cancer-early/american-ca...) that also offer their own recommendations, but these are often contradictory.

> The records of all births, deaths, and surgeries are known.

Actually, this is not known (at least in the US). There is no central medical database or significant communication between hospital systems. As you can imagine, this is problematic for obtaining meaningful data. In order to answer the questions you raise, researchers have to begin collecting new data prospectively or look retrospectively at the incomplete records contained within their hospital system. The retrospective method is easier and probably more common, but there are serious biases with a retrospective approach, including small sample sizes and non-random sampling (many US hospitals serve specific demographics).

"There is no central medical database or significant communication between hospital systems."

I find this somewhat astonishing and deeply troubling. How can patients or doctors truly make informed decisions if they are not in fact well informed? This is not right at all.

In my opinion, this is partially the flip side to prioritizing data privacy. HIPAA has been very successful in getting hospitals and healthcare organizations to take patient data privacy seriously, but HIPAA has also disincentivized these organizations from sharing data in a reasonable way even for truly altruistic purposes (e.g. research). And the idea of creating a central medical database just feels like a massive legal headache with huge consequences if anything goes wrong.

The other party responsible for the lack of centralized data is the EMR vendors (Epic being one of the largest). They're incentivized to lock-in their clients (i.e. hospitals) by making any kind of data sharing at best a pain in the ass and at worst entirely impossible. For large health systems, I've heard the cost of changing EMRs is in the tens to hundreds of millions (USD).

Besides the detriment to research, this does lead to real patient harms. Where I went to med school, there were two major hospitals systems about 5 mins from each other in a major city. I worked in the emergency department at one hospital where I would frequently see patients coming in after car accidents and heart attacks. But often, some of these patients had received all of their care at the hospital 5 mins away. We had zero records for these patients. Meaning, we had to work them up from scratch and any important medical history would be unbeknownst to us. This obviously led to poor care and duplication of medical tests, which can be harmful (e.g. radiation from CTs). And requesting medical records from the other hospital was infeasible in emergencies. Realistically, these records were only available 9a–5p on weekdays via fax at the other hospital's leisure.

That is an excellent question, thank you for clarifying.

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