Unmasking the Hidden Threat: The Vital Role of Paraneoplastic Neurological Syndrome Testing in Pediatric Neuroimmune Diseases
撰文：中國醫藥大學兒童醫院兒童神經科 洪宣羽醫師
By Dr. Syuan-Yu Hong, Department of Pediatric Neurology, China Medical University Children’s Hospital
簡介
腫瘤性神經症候群（Paraneoplastic neurological syndromes, PNS）是兒童中罕見但嚴重的疾病，通常表現為各種神經症狀，如腦病變、小腦共濟失調和運動障礙。這些症候群由潛在的惡性腫瘤引起，其中神經母細胞瘤是兒童中最常見的癌症之一。雖然這些症狀可能與其他常見的神經疾病相似，但其根本原因——癌症——需要針對性干預。腫瘤性神經症候群測試已被證明是診斷這些隱性疾病的重要工具，確保早期發現並及時治療。
病例介紹
讓我與大家分享一個6歲男孩Liam的病例，他因為行走困難、持續嘔吐和明顯的行為改變來到我們醫院。他的母親報告說，這些症狀突然出現並在過去幾周惡化。最初，Liam是一個精力充沛且愛交際的孩子，但最近，他變得嗜睡、易怒，並且越來越無法完成基本的任務，例如拿湯匙或寫自己的名字。
在身體檢查中，Liam表現出小腦共濟失調、高反射和異常的眼球運動。他也無法在不支撐的情況下行走，且說話緩慢且含糊。這些發現表明中樞神經系統受到影響，但病因仍不明。
鑑於症狀的突然發作和缺乏家族性神經疾病史，我們決定進行進一步檢查，包括腫瘤性抗體篩查。令我驚訝的是，檢測結果顯示抗Hu抗體陽性，這與腫瘤性神經症候群密切相關，且通常與神經母細胞瘤相關聯。隨後進行的全身掃描，包括腹部超音波檢查，顯示他腎上腺有一個腫塊，最終確診為神經母細胞瘤。
值得注意的是，Liam的病例強調了在兒童中面對無法解釋的神經症狀時，考慮腫瘤性神經症候群的重要性。如果沒有針對性測試，這個腫瘤可能會未被發現，直到為時已晚。早期的檢測使我們能夠將他轉診至腫瘤科治療，在經過幾輪化療後，他的神經症狀顯著改善。
腫瘤性神經症候群測試的重要性
Liam的病例突顯了腫瘤性神經症候群測試在兒科神經學中的關鍵作用。腫瘤性神經症候群在沒有適當測試的情況下很難診斷，因為其症狀通常與其他常見病症，如病毒感染或自體免疫疾病相似。然而，正如Liam的案例所示，當症狀無法解釋且對常規治療無反應時，考慮腫瘤性神經症候群是至關重要的。
在兒科患者中，及時進行腫瘤性測試可以對這些複雜病例的診斷和管理產生巨大影響。通過識別如抗Hu或抗Yo等與神經母細胞瘤和其他癌症相關的抗體，臨床醫生可以及時診斷潛在的惡性腫瘤並開始治療，這可能挽救孩子的生命並改善長期的神經學預後。
“作為兒童神經科醫生，我見過很多最初被忽視的腫瘤性神經症候群病例。我們必須保持警覺，並在治療那些神經症狀無法解釋的兒童時考慮所有可能性。早期檢測不僅是治療孩子的神經症狀，更是處理潛在致命癌症的根本原因。越早診斷，孩子的恢復機會就越大” 洪宣羽醫師緩緩地說道。
結論
在兒童中診斷腫瘤性神經症候群往往具有挑戰性，但卻極為重要。及時和有針對性的腫瘤性測試可以導致對潛在惡性腫瘤的早期識別，從而進行早期干預和治療。作為兒童神經科醫生，我們必須積極主動地考慮這些症候群，即使症狀似乎沒有明確的病因。通過這樣做，我們可以確保為我們的年輕患者提供最佳的治療效果。
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Introduction
Paraneoplastic neurological syndromes (PNS) are rare but serious conditions in children, often presenting with a variety of neurological symptoms such as encephalopathy, ataxia, and movement disorders. These syndromes are triggered by an underlying malignancy, with neuroblastoma being one of the most common cancers in pediatric cases. While the symptoms may resemble more common neurological disorders, the underlying cause—cancer—requires targeted intervention. Paraneoplastic syndrome testing has proven to be a vital tool in diagnosing these elusive conditions, ensuring early detection and appropriate treatment.
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Case Presentation
Let me share with you the case of a 6-year-old boy, Liam, who came to our hospital plaints of difficulty walking, persistent vomiting, and a noticeable change in his behavior. His mother reported that these symptoms had appeared suddenly and worsened over the past few weeks. Initially, Liam had been an energetic and social child, but recently, he became lethargic, irritable, and increasingly unable to perform basic tasks such as holding a spoon or writing his name.
On physical examination, Liam showed signs of cerebellar ataxia, hyperreflexia, and abnormal eye movements. He was also unable to walk without support, and his speech was slow and slurred. These findings pointed toward a central nervous system involvement, but the cause was unclear.
Given the sudden onset of symptoms and the absence of a family history of neurological disorders, we decided to proceed with further testing, including paraneoplastic antibody screening. To my surprise, the test came back positive for anti-Hu antibodies, which are strongly associated with paraneoplastic syndromes and commonly linked to neuroblastoma. A full body scan, including an abdominal ultrasound, revealed a mass in his adrenal gland, confirming the diagnosis of neuroblastoma.
Remarkably, Liam’s case underscores how crucial it is to consider paraneoplastic neurological syndromes in children with unexplained neurological symptoms. Without the targeted testing, it is possible that his malignancy could have gone undetected until it was too late. Early detection enabled us to refer him for oncology treatment, and after several rounds of chemotherapy, his neurological symptoms improved significantly.
The Importance of Paraneoplastic Neurological Syndrome Testing
The case of Liam highlights the critical role that paraneoplastic neurological syndrome testing plays in pediatric neurology. Paraneoplastic neurological syndromes can be difficult to diagnose without the appropriate tests, as their symptoms often mimic other common conditions, such as viral infections or autoimmune diseases. However, as in Liam’s case, when the symptoms are unexplained and do not respond to conventional treatments, it is essential to consider paraneoplastic syndrome.
In pediatric patients, timely paraneoplastic testing can make a huge difference in the diagnosis and management of these complex cases. By identifying antibodies such as anti-Hu or anti-Yo, which are associated with neuroblastoma and other cancers, clinicians can promptly diagnose the underlying malignancy and initiate treatment, potentially saving the child’s life and improving long-term neurological outcomes.
“As a pediatric neurologist, I have seen many cases where paraneoplastic neurological syndromes were initially overlooked. It’s essential that we remain vigilant and consider all possibilities when treating children with unexplained neurological symptoms. Early detection is not just about treating the child’s neurological symptoms but also addressing the root cause, which is often a life-threatening malignancy. The earlier we diagnose, the better the chances for recovery.” Dr. Syuan-Yu Hong said slowly
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Conclusion
The diagnosis of paraneoplastic neurological syndrome in children is often challenging but extremely important. Timely and targeted paraneoplastic testing can lead to early identification of underlying malignancies, allowing for early intervention and treatment. As pediatric neurologists, it is crucial that we stay proactive in considering these syndromes, even when symptoms seem to have no clear cause. By doing so, we ensure the best possible outcomes for our young patients.
洪宣羽 醫師
中國醫藥大學兒童醫院兒童神經科
