I think it's just a badly phrased sentence. I'm pretty sure it should read something like: "If you have an underlying neoplasm (tumor) like these patients had

I think it's just a badly phrased sentence. I'm pretty sure it should read something like: "If you have an underlying neoplasm (tumor) like these patients had, then the risk [of not treating the tumour] outweighs the benefit," he said. "However, if you are doing well on ARVs and you merely want to get off antiretroviral therapy, then the risk [of the transplant] seems greater than the benefit."