Since the nick was caught relatively early on, a nicked intestine is a common risk of colon surgery, and your husband is on his way to recovery, it may be difficult to make a case for medical malpractice. If you would like to be sure, I would contact a medical malpractice attorney in your area, though beware that you may be asked to share the cost of an expert review. I hope that your husband's cancer was caught early, and that he makes a full recovery.
Nicks to the organ or even adjacent anatomy during an invasive surgery are considered accepted risks of the procedure. This means that the injury can happen even in the absence of negligence & when the surgeon does everything right. In other words, the injury itself is not proof of a surgical misadventure. You need more than that to show that the doctor used poor technique. It usually becomes an insurmountable proof-problem as the operative report will probably give you no clues as to what the surgeon did wrong (if anything).
Yes a nick can happen, but given what your husband went through I would contact a local attorney who handles malpractice case to review the records. Since we don't know where the "nick" was, you can't presume it is just a known complication. While it is a possibility, given the problems your husband has had, it is worth looking into.
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