[tom_b]

Sure. There are teams doing it every day right now, with clinical patients. It's still research, but we are pushing variant calls back into patient's medical record to help make treatment decisions.

From a complexity perspective, not nearly as much as you would think (by which I mean there are many software tools that already do this pretty efficiently). The day-to-day problems are much simpler (and more standard IT) than you might think. For example, you can safely assume that finding variants is done. Now, where is the source of drugs that are in clinical trial or in approved treatments for a specific mutation. Can you get that in front of pathologists quickly?

You probably want to take a look at The Cancer Genome Atlas (TCGA) project. They are sequencing normal and tumor tissue from patients across a large number of cancer types and making the resulting sequence data available for research.

Edit (additional info): It does NOT take a month to do this sequencing and it is getting tremendously quicker every day. The MiSeq from Illumina can pump out the fastq file from a normal or tumor sample in 24 hours (and it can do something like 96 samples at a time, but I don't know if people push that in production).