Abstract: Objective To study the clinical and pathologic characteristics of malignant lymphoma misdiagnosed as tuberculosis and its misdiagnosed reasons.Method The clinical and pathologic manifestations,X-ray features,diagnosis and treatments of 27 diagnosed malignant lymphoma cases misdiagnosed as tuberculosis from 1996 to 2003 were retrospectively analyzed.Results There were no specific clinical characteristics.The most common symptoms were fever(19/27),cough(8/27) and hemoptysis(1/27),8 cases without of symptoms(29%),the enlargement of the lymph nodes were in found in 22 cases.The X-ray showed as bumpnade lesions(10 cases),diffuse lesions(5 cases),hilar lymphadenopathy(11cases),pleural effusion(10 cases).Confirmed diagnosis was made by pathologic and immunohistochemical examinations through lymph node excision(22cases),bronchoscopy(2cases),or percutaneous needle lung biopsy(3cases).and 7 cases were confirmed as Hodkin’s lymphomas and 20 cases without Hodkin’s lymphomas.The main treatment Methods were radiotherapy and chemotherapy.The treatment outcome was poor.Conclusion There were similarities on clinical and pathologic manifestations,X-ray features between malignant lymphoma and tuberculosis.Misdiagnosis was common.Appropriate invasive biopsy procedures were necessary for early diagnosis.

Key words: malignant lymphoma, Tuberculosis, misdiagnosis