3 ms·

> 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 bankruptc

by sxg 6y ago

> 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.

floatingatoll 6y ago
That is an excellent question, thank you for clarifying.
thret 6y ago
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.
- sxg 6y ago
  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.
  - thret 6y ago
    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?
    - sxg 6y ago
      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/recommendation-topics/uspstf-and-b-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-cancer-society-guidelines-for-the-early-detection-of-cancer.html 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).

by sxg 6y ago

floatingatoll 6y ago

That is an excellent question, thank you for clarifying.

thret 6y ago

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.

sxg 6y ago
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.
- thret 6y ago
  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?
  - sxg 6y ago
    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/recommendation-topics/uspstf-and-b-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-cancer-society-guidelines-for-the-early-detection-of-cancer.html 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).