This forum is for questions and support regarding neurology issues such as:
Alzheimer's Disease,
ALS,
Autism, Brain Cancer,
Cerebral Palsy, Chronic Pain,
Epilepsy,
Fibromyalgia, Headaches, MS, Neuralgia, Neuropathy, Parkinson's Disease, RSD, Sleep Disorders,
Stroke, Traumatic Brain Injury
First of all I'm sorry to hear that you are experiencing all these things. I suggest you get a second opinion from another neurologist. This is really a chicken and egg question of which came first. If you have small cell cancer or lymphoma, then the additional finding of ataxia and nystagmus maybe called a paraneoplastic syndrome (this is rather a rare paraneoplastic syndrome). However, if you are initially diagnosed with ataxia and nystagmus, the chance of this being due to cancer is very low and there are lots of conditions that should be thought of first than cancer (like stroke, vertebrovascular insufficiency, etc.).
I suggest you arrange consult with another neurologist and discuss the things that I have mentioned.
I hope this helps. Good day and God bless...