Anti-Hu paraneoplastic syndromes are usually associated with an underlying neoplasia, although a few patients who are anti-Hu-positive never develop cancer after long-term follow-up. Tumour therapy remains the mainstay of therapeutic options, and early immune therapy in parallel is advisable. When no tumour is found, immunologically-based therapies are nowadays the only options. Recent studies have shown rituximab associated with the tumour therapy to be effective for some patients with anti-Hu paraneoplastic syndrome. We report a case of a patient with anti-Hu antibodies-associated sensory neuronopathy and gastric pseudo-obstruction without an underlying neoplasia four years after the first manifestation who has achieved sustained improvement for two years after treatment with rituximab. This case report supports the effectiveness of rituximab in these syndromes, even for cases where no underlying neoplasia is demonstrated. Further studies are warranted in order to confirm these preliminary data.