Why is a new biopsy sometimes needed?

Even if you have already had one or more biopsies or surgeries in the past, a new biopsy may still be needed. There may be several reasons for this. Additional research may need to be done on tumour tissue to check whether you are eligible for a particular new treatment or clinical trial. In case insufficient tissue is available or in case it was collected too long ago, it may be necessary to perform a new biopsy. Also, if there is doubt about the character of a particular lesion and radiological studies are inconclusive, a new biopsy may be appropriate to ensure that you receive the best possible treatment.