Primary esophageal marginal zone lymphoma with respiratory symptoms: a case report and review of the literature.

Background: Primary esophageal lymphoma is a rare disease whose pathogenesis may be related to immune abnormalities. We report a case of primary esophageal marginal zone lymphoma (MZL) in the esophagus for 2 years, which initially presented with respiratory symptoms and was subsequently diagnosed by endoscopic ultrasound-guided fine-needle aspiration. Case presentation: A 68-year-old male presented with a 10-day history of cough, excessive sputum production, and wheezing after physical activity. Two years prior to this admission, the patient had sought medical attention at our hospital for fever and cough. After completing the relevant examinations, the preliminary diagnosis was considered to be a pulmonary infection, with the possibility of an esophageal neoplastic lesion. Upon readmission, a follow-up chest CT revealed thickening of the esophageal wall in multiple segments, which was more pronounced than it had been 2 years previously, and tracheal compression. Upper gastrointestinal endoscopy revealed a widespread, protruding lesion along the entire esophagus, with a smooth mucosal surface and no ulceration. Endoscopic ultrasound revealed the disappearance of the normal layered structure of the esophageal wall at the site of the lesion. PET-CT demonstrated uneven increased radioactive uptake throughout the esophagus. Bone marrow aspiration did not reveal any tumor involvement. Histopathological and immunohistochemical examinations revealed marginal zone lymphoma. Conclusion: Primary esophageal lymphoma has significant clinical heterogeneity, typically starting with progressive dysphagia and weight loss. This patient has a long history of atypical symptoms, representing the first case to present with respiratory symptoms without dysphagia. Due to the extremely low incidence of primary esophageal lymphoma and the lack of typical symptoms, imaging findings, and endoscopic manifestations, it is prone to misdiagnosis. Differential diagnosis is necessary to distinguish it from esophageal malignancies such as esophageal squamous cell carcinoma and esophageal adenocarcinoma, as well as benign esophageal conditions like esophagitis and esophageal tuberculosis. Performing endoscopic ultrasound-guided fine needle aspiration to complete pathological biopsy is crucial to reduce the risk of misdiagnosis and facilitate early diagnosis. Currently, after two courses of the G-CVP regimen (Obinutuzumab + Cyclophosphamide + Vincristine + Prednisone) demonstrated suboptimal efficacy, the treatment was switched to a triple combination of Obinutuzumab, Orelabrutinib, and Lenalidomide, which has now completed six courses.