How Serious Can A Carcinoid Syndrome Be, With An Elongated

How serious can a Carcinoid Syndrome be, with an elongated pymph node located near the base of the spine, at the back of the abdomen ? Can it be fatal, or can it be treated ? Long before the current testing and speculation, there has been been severe spinal/sciatic nerve pain. Is it possible that the Carcinoid tumour, whether it proves malignant or not, could be pressing on the spinal nerve ?
Thank you.