Paraneoplastic Syndromes

A paraneoplastic syndrome is a set of signs and symptoms that can occur when you have cancer. The symptoms develop when a malignant tumor causes changes in your body that aren’t directly caused by the cancer itself. Usually, they occur when your immune system releases antibodies to destroy the tumor. In the process, the antibodies also damage healthy cells, causing symptoms.

Sometimes, the symptoms of a paraneoplastic syndrome are the first signs of cancer.

Types of paraneoplastic syndromes

The different types of paraneoplastic syndromes affect various body systems and parts. The most common ones involve your:

• Nervous system (brain, spinal cord and nerves)
• Endocrine system (hormones)
• Connective tissue (bones and joints)
• Blood
• Skin

Nervous system paraneoplastic syndromes

Paraneoplastic syndromes that affect your nervous system include:

• Cerebellar degeneration
• Dysautonomia
• Encephalitis
• Lambert-Eaton myasthenic syndrome
• Myasthenia gravis
• Myelopathy
• Neuromyotonia
• Peripheral neuropathy
• Stiff person syndrome

Endocrine system paraneoplastic syndromes

Paraneoplastic syndromes that impact how your hormones work include:

• Carcinoid syndrome
• Cushing syndrome
• Hypercalcemia
• Syndrome of inappropriate antidiuretic hormone secretion

Rheumatologic paraneoplastic syndromes

Examples of paraneoplastic syndromes that affect your bones, joints and muscles include:

• Dermatomyositis
• Eosinophilic fasciitis
• Erythromelalgia
• Hypertrophic osteoarthropathy
• Palmar fasciitis
• Paraneoplastic polyarthritis

Blood paraneoplastic syndromes

Syndromes that impact your blood cells include:

• Anemia of chronic disease
• Disseminated intravascular coagulation
• Paraneoplastic erythrocytosis
• Paraneoplastic thrombocytosis

Skin paraneoplastic syndromes

Examples include:

• Acanthosis nigricans
• Dermatomyositis
• Leukocytoclastic vasculitis
• Paraneoplastic pemphigus
• Sweet syndrome

Symptoms of paraneoplastic syndromes

Common symptoms include:

• Fever
• Loss of appetite
• Night sweats
• Unexplained weight loss

Syndromes that affect particular organs or systems can cause symptoms specific to those body parts. Here’s a snapshot of possible signs and symptoms:

• Nervous system: Double vision, memory loss, confusion and trouble coordinating your muscles
• Endocrine system: High blood pressure and unexplained weight gain
• Connective tissue: Joint pain, swelling and weakness
• Blood: Having too few or too many blood cells
• Skin: Benign (noncancerous) growths, flushing and itching

Paraneoplastic syndrome causes

With a paraneoplastic syndrome, cancer leads to changes in your body that happen secondary to cancer instead of directly. The differences can be confusing, so try thinking of it this way:

You may have pain if a tumor grows so big that it puts pressure on an organ. Related, an organ may stop functioning correctly if cancer spreads to the area and damages it. In these cases, the cancer causes symptoms directly.

But paraneoplastic syndromes happen because the tumor’s presence in your body causes things to go wrong. To destroy the tumor, your body’s defense system may misfire and harm healthy tissue. This is called an autoimmune response. Some tumors release hormones that cause organs to work improperly. The hormones — not the tumor itself — can cause damage without treatment.

Risk factors

Anyone with cancer can develop a paraneoplastic syndrome. Experts estimate that about 8 out of every 100 people (8%) with cancer develop one. The types of cancer most commonly associated with paraneoplastic syndromes are:

• Lung cancer (most common)
• Breast cancer
• Blood cancer
• Ovarian cancer

How doctors diagnose this condition

Healthcare providers diagnose paraneoplastic syndromes with a medical history, physical exam and several tests:

• Blood tests: Routine blood work can help rule out benign conditions that may be causing your symptoms. Blood tests for cancer can reveal substances that may be a sign of a paraneoplastic syndrome.
• Imaging: Your provider may use a CT scan, MRI or ultrasound to look for a tumor.
• Neurological exam: Your provider may ask you to perform tasks to check your nervous system. They’ll look for changes related to your strength, memory and coordination.
• Spinal tap: A spinal tap tests the fluid surrounding your spinal cord for signs of antibodies attacking healthy cells.

How are paraneoplastic syndromes treated?

Most importantly, your healthcare provider will treat the cancer. They’ll also work to manage your symptoms. Most treatments calm your immune system so it doesn’t attack healthy cells.

Therapies that manage paraneoplastic syndromes include:

• Corticosteroids: Medicines like cortisone and prednisone reduce inflammation and swelling.
• Immunosuppressants: These drugs decrease your body’s immune response.
• Intravenous immunoglobulin: This treatment destroys harmful antibodies.
• Plasmapheresis: This procedure decreases your antibodies by removing plasma (the liquid part of your blood). They filter the antibodies that damage tissue out of the plasma.
• Physical, occupational and speech therapy: You may need therapy to help with your movement or speech if you have a neurological paraneoplastic syndrome.

When should I see my healthcare provider?

See a healthcare provider if you have unusual symptoms that are severe or that last for two weeks or more.

Remember that many conditions have the same symptoms of paraneoplastic syndromes. And most aren’t as serious as cancer. So, don’t assume the worst. But you should still see a provider to get checked out.

If you’re experiencing symptoms and have received cancer treatment within the last five years, it’s a good idea to get re-screened. Re-screening can alert your provider if the cancer has returned.

What can I expect if I have this condition?

Your outlook (prognosis) depends on the cancer. Paraneoplastic syndromes may cause mild, temporary symptoms. Other times, they cause severe symptoms that need long-term management.

Your provider will explain how your diagnosis may impact your health.

What is the most common paraneoplastic syndrome?

One of the most common paraneoplastic syndromes is peripheral neuropathy. It involves nerve damage that can make it harder to use your muscles. It can cause unusual tingling sensations and numbness. It can also disrupt your sense of touch.

What is the best treatment for paraneoplastic syndrome?

The best treatment for a paraneoplastic syndrome is the one that’s best at treating the cancer. Your healthcare provider can recommend therapies to manage symptoms while you’re getting cancer treatment.