All authors approved the final draft. Funding None. Availability of data and materials Data EG01377 TFA sharing is not applicable to this article as no datasets were generated or analyzed during the current study. Declarations Ethics approval and consent to participate DNM1 Not applicable. HL was made based on cerebrospinal fluid changes with a strong positive reaction to anti-Tr/DNER antibodies, FDG-PET/CT scan, and biopsy findings. The medical history revealed that the patient had been diagnosed with HL previously, but has been in complete remission for 12 years. The patient was treated with intravenous immunoglobulin, chemo- and radiation therapy. Over the following 6C8 weeks he improved. Conclusions Late relapse in HL is very rare. If it occurs it presents as a symptomatic lymphadenopathy. Our case shows, that PCD can be the only presenting symptom of a very late relapse of HL. Paraneoplastic neurological syndromes (PNS) should be considered even in patients with very long cancer remission. PCD can in rare cases mimic a stroke within the posterior circulation. If MR imaging in severe acute/subacute cerebellar syndrome is usually normal further investigation is usually mandatory to rule out a PNS, particular in patients with a previous cancer. strong class=”kwd-title” Keywords: paraneoplastic syndrome, cerebellar degeneration, Hodgkin lymphoma, relapse Introduction Paraneoplastic cerebellar degeneration (PCD) is usually a classic neurological syndrome associated with well-characterized onconeuronal antibodies and the presence of a cancer. Among several onconeuronal antibodies in PCD, the presence of Anti-Tr/DNER (Delta/notch-like epidermal growth factor-related receptor) is usually strongly associated with Hodgkin Lymphoma (HL) [1C3]. Normally PCD is usually recognized by clinical features but in some patients the diagnosis can be a challenge, particularly in those with no active or recent malignancy and in those with an acute onset. Awareness of the syndrome is usually important because with prompt treatment the prognosis of HL is usually good with an overall 5-year survival of 87?% [4]. Normally PCD precedes the diagnosis and thereby its presence leads to the discovery of a HL [1, 2], which otherwise had remained undiagnosed. The late relapse rate in HL is only 3.5?% after 5 years and if it occurs it usually presents as symptomatic lymphadenopathy and/or B-symptoms [4]. Opposite, to the well-documented value of early identification of a paraneoplastic neurological syndrome (PNS) in patients with unknown malignancy, the importance of these syndromes in the detection of a cancer relapse is not clarified. We report the case of a 76-year-old man where a PCD, initially misdiagnosed as a stroke led to a diagnosis of a very late relapse of HL after 12 years. Case presentation A 76-year-old male with a 3-week history of unstable walking, slow speech and dizziness was admitted to our stroke unit. An MRI-scan showed no signs of acute ischemia. Further investigations were not performed and he was discharged. The neurological symptoms progressed further over the next 2 weeks and the patient was re-admitted. On examination, he was unable to walk due to truncal ataxia and he had a severe dysarthria. He was alert, without weakness, pyramidal signs, cranial nerve affection or sensory deficits e.g., the neurological signs were purely cerebellar. He denied B-symptoms (fever, night sweats, or unintended weight loss). A repeated MRI-scan was still without structural abnormalities. Routine hematological and biochemical investigations were within normal limits. Cerebrospinal fluid (CSF) examination showed moderate pleocytosis, elevation of protein level at 1.12?g/L (range: 0.15C0.50?g/L), normal IgG-index but an oligoclonal band was present. There were no neoplastic cells and flowcytometry was normal. Screening for antibodies to paraneoplastic neurological syndromes was performed by indirect immunofluorescence test (Euroimmun, Lbeck, Germany) and confirmed by using EUROLINE profiles neuronal antigens, 12 recombinant EG01377 TFA antigens (amphiphysin, CV2, PNMA2 (Ma2/ta), Ri, Yo, Hu, recoverin, SOX1, Titin, Zic4, GAD65 and anti-Tr/DNER (Euroimmun, Lbeck, Germany). The assessments showed a strong reaction to anti-Tr/DNER antibodies in both serum and CSF. Immunoreaction against other paraneoplastic antibodies and the mGluR1 and mGluR5 receptor were unfavorable. 18F-FDG positron emission tomography/contrast EG01377 TFA enhanced computed tomography (FDG-PET/CT) scan revealed a round structure with moderate FDG uptake in the left submandibular gland (Fig.?1) suggesting a Warthin tumor (lymphomatous papillary cystadenoma). He underwent extirpation of the process which appeared EG01377 TFA to be a lymph node in close vicinity to the submandibular gland. The node had.