Successful treatment of diffuse large B-cell lymphoma with clarithromycin and prednisolone
A 71-year-old woman was admitted to hospital with fever and cervical pain. For the previous year, she had been treated with antituberculars for non-tuberculous mycobacteria (NTM) infection of the lung after detection of Mycobacterium avium in her sputum. Her symptoms reappeared approximately 10 months after completion of antitubercular therapy, and just prior to admission, she had received levofloxacin then amoxicillin for fever based on suspicion of recurrent NTM or another pulmonary infection. However, while chest radiography revealed no new lesions, her symptoms did not improve.\nOn admission, physical examination showed several swollen lymph nodes in the left axillary region. Lactate dehydrogenase levels were 148 IU/L and serum soluble interleukin-2 receptor (sIL-2R) levels were increased to 928 U/mL. Chest computed tomography (CT) revealed axillary lymphadenopathy () accompanied by slight infiltration shadows of NTM in the right lung field. Abdominal CT revealed neither para-aortic nor inguinal lymphadenopathy. Bone CT revealed bone destruction of the axis (). Bone scintigram revealed uptake into the vertebrae, sternum, ribs, left scapula, pelvis, and right femur (). Magnetic resonance imaging revealed high-intensity areas in the cervical and thoracic vertebrae on T2-weighted imaging. Fluorodeoxyglucose (FDG)-positron emission tomography (PET) demonstrated increased spotty uptake of FDG into the vertebrae, sternum, ribs, pelvis, right femur, and bilateral axillary lymph nodes (). Along with spotty uptake, moderate serial uptake into the cervical to lumbar-region vertebrae was also evident (). Esophagogastroduodenoscopy and colonoscopy showed no abnormal lesions associated with malignancy. No malignant gynecological lesions were found. Biopsy specimens from the left axillary lymph nodes revealed an absence of follicular structures and diffusely proliferative large lymphoid cells with pleomorphic, irregular nuclei and prominent nucleoli, accompanied by small lymphoid cells (). Immunohistochemical staining revealed that the large lymphoid cells were positive for CD20, bcl-2, and MIB-1 (), but negative for CD3, CD30, and EBER. MIB-1 proliferation index was 40%. The small lymphoid cells were positive for CD3 but negative for CD20. Ziehl-Neelsen staining for acid-fast bacilli yielded negative results. Biopsy specimens were inadequate for conducting chromosomal analysis or determining genetic rearrangements in the axillary lymph nodes. Although neither bone marrow aspiration specimens nor bone marrow biopsy specimens from the ileum revealed large lymphoid cells, the results of bone CT, bone scintigraphy, and FDG-PET indicated multiple lesions of the bone and bone marrow. Based on these findings, she was diagnosed with clinical stage IV DLBCL, with low-to-intermediate risk according to the international prognostic index []. Her cervical pain was thought to be due to invasion of the lymphoma cells into the cervical vertebrae.\nShe initially received radiotherapy for the cervical lesions to avoid neurological symptoms. She subsequently declined conventional chemotherapy due to the risk of recurrent NTM infection. We therefore began treatment with CAM (800 mg/day) and PSL (20 mg/day) on the condition that conventional chemotherapy would be started immediately if DLBCL exacerbation was observed. Fever improved within a few days. The PSL dosage was initially 20 mg/day for 2 weeks and subsequently 15 mg/day for 2 weeks. The maintenance dosage was 10 mg/day. Her sIL-2R levels decreased from 928 to 619 U/mL approximately 2 months after beginning CAM and PSL treatment. At that time, contraction of the axillary lymph nodes was found on CT. Complete remission (CR) was achieved after 6 months, with improvements in lymphadenopathy and lesions of the bone and bone marrow apparent on both CT () and FDG-PET (). The sIL-2R levels decreased to 215 U/mL. Slightly reduced taste sensation was reported, and was considered a side effect of long-term CAM use. She remains in CR 7 months after initiation of treatment.