Overview
Paraneoplastic neurologic syndrome (PNS), also called paraneoplastic neurological syndrome or cancer-related neurological syndrome, is a rare condition where the immune system's response to a hidden cancer accidentally attacks the nervous system. Instead of only targeting the tumor, the immune system produces antibodies or immune cells that mistakenly damage the brain, spinal cord, nerves, or muscles. This 'friendly fire' causes serious neurological problems that can appear before the cancer is even discovered — sometimes months or years earlier. The nervous system damage can affect many different areas, leading to a wide range of symptoms depending on which part is attacked. Common forms include cerebellar degeneration (causing balance and coordination problems), limbic encephalitis (affecting memory and behavior), sensory neuropathy (causing numbness and pain), and Lambert-Eaton syndrome (causing muscle weakness). The most commonly associated cancers are small cell lung cancer, breast cancer, ovarian cancer, and thymoma. Treatment focuses on two main goals: finding and treating the underlying cancer, and calming the immune system to reduce nerve damage. Immunotherapy drugs such as corticosteroids, intravenous immunoglobulin (IVIG), and plasma exchange are commonly used. Early diagnosis and cancer treatment offer the best chance of stabilizing or improving symptoms, though recovery varies widely from person to person.
Also known as:
Key symptoms:
Loss of balance and coordination (difficulty walking or using hands)Memory problems and confusionPersonality or behavior changesNumbness, tingling, or pain in the hands and feetMuscle weakness, especially in the legsDifficulty swallowing or speakingInvoluntary eye movements or double visionSeizuresHearing lossDizziness or vertigoDifficulty controlling bladder or bowelFatigue and general weaknessMood changes, anxiety, or depression
Sporadic
Usually appears on its own, not inherited from a parent
Adult
Begins in adulthood (age 18 or older)
FDA & Trial Timeline
10 eventsKonya Beyhekim Training and Research Hospital — NA
Mersin University
University of Castilla-La Mancha — NA
Marmara University
Rijnstate Hospital
Foundation University Islamabad — NA
University Hospital Schleswig-Holstein — NA
Fudan University
The University of Texas Health Science Center, Houston — NA
Ospedale Policlinico San Martino — NA
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Paraneoplastic neurologic syndrome.
1 clinical trialare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Paraneoplastic neurologic syndrome.
Community
No community posts yet. Be the first to share your experience with Paraneoplastic neurologic syndrome.
Start the conversation →Latest news about Paraneoplastic neurologic syndrome
Disease timeline:
New recruiting trial: Comparative Effects Between ELDOA and Spinal Mobilization With Limb Movement in Lumbar Radiculopathy
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: Migraine and Neuropathic Pain in Osteoarthritis
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: Evaluation of Effectiveness of Closed-loop Spinal Cord Stimulation (CL-SCS) Therapy for Treatment of Chemotherapy Induced Peripheral Neuropathy
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: Implementation of the Pain and Irritability of Unknown Origin (PIUO) Pathway in Community Pediatric Practices
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: A Causative Role for Amylin in Diabetic Peripheral Neuropathy
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: High-frequency Alternating Current Stimulation for Neurophatic Pain in Spinal Cord Injury
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: Peripheral Nerve Stimulation of Genicular Nerves Versus Conventional Therapy With Intra-articular Steroid Injection for Chronic Knee Pain: A Prospective, Randomized Pilot Study
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: USG-Guided Shoulder Injections in Frozen Shoulder
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: Cortical Stimulation by Direct Current for the Treatment of Chronic Pain : Pilot-study of a Stimulation Device at Home
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
New recruiting trial: Prognostic Value of Biomarkers in Polyneuropathy.
A new clinical trial is recruiting patients for Paraneoplastic neurologic syndrome
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.Which specific antibody was found in my blood or spinal fluid, and what does that tell us about my prognosis?,Has a cancer been found, and what is the plan to search for one if not yet identified?,Which immune-suppressing treatments do you recommend for me, and what are the risks?,How will we know if the treatment is working, and how often will I be monitored?,What rehabilitation therapies should I start, and how soon?,Are there clinical trials I might be eligible for?,What symptoms should prompt me to go to the emergency room immediately?
Common questions about Paraneoplastic neurologic syndrome
What is Paraneoplastic neurologic syndrome?
Paraneoplastic neurologic syndrome (PNS), also called paraneoplastic neurological syndrome or cancer-related neurological syndrome, is a rare condition where the immune system's response to a hidden cancer accidentally attacks the nervous system. Instead of only targeting the tumor, the immune system produces antibodies or immune cells that mistakenly damage the brain, spinal cord, nerves, or muscles. This 'friendly fire' causes serious neurological problems that can appear before the cancer is even discovered — sometimes months or years earlier. The nervous system damage can affect many diff
How is Paraneoplastic neurologic syndrome inherited?
Paraneoplastic neurologic syndrome follows a sporadic inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
At what age does Paraneoplastic neurologic syndrome typically begin?
Typical onset of Paraneoplastic neurologic syndrome is adult. Age of onset can vary across affected individuals.
Are there clinical trials for Paraneoplastic neurologic syndrome?
Yes — 1 recruiting clinical trial is currently listed for Paraneoplastic neurologic syndrome on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Paraneoplastic neurologic syndrome?
24 specialists and care centers treating Paraneoplastic neurologic syndrome are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.