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Comment by troels | Hacker News Reader

There's an unsaid implication that it is possible to sub-type cancers based on a patients genetic type. E.g. what makes a particular drug work on a particular cancer form, is determined by that patients genetics. Is this a generally accepted assumption?

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This technique is coming into prominence but genomic is still a very young science with the cost of sequencing only recently coming down enough to have it become regular practice. What we have now are essentially a shortlist of known mutations that are seen across many cancers, a huge list of closely associated mutations in the same pathway or impinging pathways that are sometimes seen in conjunction with other mutations, sometimes not and then a ton of noise from which researchers are trying to pick out possible correlation. The vast majority of mutations are not cancer causing, so picking out the ones that are is difficult. That being said, frequently broad characterization can be done. This person has an effected PI3Kinase, or MAP pathway. We only have drugs for a few of the major mutations so once the cancer mutates to avoid drugging, patients are often out of luck.

To answer your second question, cancer is generally accepted as a genetic disease ie mutations, copy number alterations, insertion and deletion of genetic information, however, recent research has shown that epigenetic processes (that is what your cells are doing with your genes such as alternative splicing or DNA methylation) are also an important factor and these can be effected by environmental factors such as diet, exercise, even mood.

it's worth mentioning that just because a mutation is seen across cancers, it may not necessarily help us cure it. Like, for example, if the downstream effect is "increases mutation rate". That's kind of "well I can see how this causes cancer", but targetting it would be too late.

> This person has an effected PI3Kinase, or MAP pathway. We only have drugs for a few of the major mutations so once the cancer mutates to avoid drugging, patients are often out of luck.

Yeah, patients relapsing into cancer usually do not have much alternatives. Combination therapies often help since they can attach several pathways at once, but combo therapies are usually limited to 2 compounds at the same time.

Another huge problem is linked to medical practice. So many doctors treating cancer patients are just NOT aware of the latest studies and developments in terms of Standards of Care. If you have a cancer, the most relevant factor is the necessarily the drug you take but who's treating you and how much he knows about your condition.

Helping doctors make decisions may be another area for disruption, where Software may help.

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