From the Guidelines
Paraneoplastic antibodies are autoantibodies produced by the immune system in response to certain cancers, targeting proteins that are normally expressed in both tumor cells and the nervous system, and their detection is crucial for the diagnosis and management of paraneoplastic syndromes. These antibodies can cause neurological symptoms that often appear before the cancer is diagnosed, serving as important diagnostic markers. Common paraneoplastic antibodies include anti-Hu (associated with small cell lung cancer), anti-Yo (linked to gynecological and breast cancers), anti-Ri (found in breast cancer), and anti-Ma2 (connected to testicular tumors) 1. The prevalence of onconeural antibodies in small cell lung cancer (SCLC) for Hu, CRMP5, amphiphysin, Yo, Ri, and Ma2 are 22.5%, 5.0%, 2.5%, 0.5%, 1.5%, and 1.0%, respectively, highlighting the importance of anti-Hu syndrome in lung cancer 1.
Key Points
- Paraneoplastic antibodies are associated with various types of cancer, including lung, breast, and testicular cancer
- These antibodies can cause neurological symptoms, such as weakness, sensory loss, and cognitive impairment
- Testing for paraneoplastic antibodies typically involves serum and sometimes cerebrospinal fluid analysis
- When paraneoplastic antibodies are detected, an extensive cancer workup is essential, including imaging studies appropriate for the suspected malignancy
- Treatment focuses on addressing the underlying cancer, which can sometimes improve the neurological symptoms, along with immunosuppressive therapies like corticosteroids, intravenous immunoglobulin, or plasma exchange to manage the immune response 1
Importance of Early Detection
Early detection and treatment of both the neurological symptoms and the underlying cancer are crucial for improving outcomes in patients with paraneoplastic syndromes. Delayed diagnosis of paraneoplastic syndromes may lead to increased complications that limit or delay cancer treatment, highlighting the need for rapid recognition, proper evaluation, and timely intervention 1. Prompt recognition and treatment of paraneoplastic syndromes is important for patients with lung cancer, and physicians need to consider and balance the benefits of treating the paraneoplastic syndrome with the potential harms associated with delays in treatment of the cancer itself 1.
From the Research
Definition of Paraneoplastic Antibodies
Paraneoplastic antibodies are autoantibodies produced by the body in response to cancer, which can cause damage to organs or tissues at locations remote from the primary tumor or metastases 2, 3, 4, 5, 6.
Characteristics of Paraneoplastic Antibodies
- They are associated with various types of cancer, including lung cancer, particularly small cell lung cancer 2, 3, 6.
- They can cause a range of symptoms, including neurologic, endocrine, dermatologic, rheumatologic, hematologic, and ophthalmological syndromes 2, 3, 6.
- They are often detected in the serum or cerebrospinal fluid of patients with paraneoplastic syndromes 4, 5.
- They can be used as a diagnostic tool to identify paraneoplastic syndromes, with some antibodies having high specificity and sensitivity 4.
Examples of Paraneoplastic Antibodies
- Anti-Hu antibodies, which are commonly associated with small cell lung cancer and paraneoplastic neurological syndromes 3, 4.
- Other antibodies that have been identified in paraneoplastic syndromes, including those affecting the central and peripheral nervous system 5.