title: Superior clinical impact of FDG-PET compared to MRI for the follow-up of a patient with sacral lymphoma.
abstract: The assessment of residual tumors after treatment of malignant lymphoma (ML) is often difficult. Here we report a case of non-Hodgkin's lymphoma with a huge sacral tumor. After chemotherapy and following radiation therapy, a residual mass was detected on magnetic resonance imaging (MRI). However, a hypermetabolic lesion in the sacrum disappeared on (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) and clinically the patient was considered to achieve complete remission. Seven months after the completion of radiation therapy, a new tumor-like lesion in the sacrum developed on MRI, but hypermetabolic lesions were not detected on (18)F-FDG-PET. Recurrence of lymphoma was denied by open biopsy of the lesion. (18)F-FDG-PET has been of widespread use not only for staging but for post-treatment assessment of ML. Although MRI is a standard imaging tool for the assessment of bone involvement of ML, there have been few reports documenting the results of comparative studies on the usefulness of (18)F-FDG-PET and MRI for the evaluation of residual mass in bone involvement of ML. The present case suggests that (18)F-FDG-PET is superior to MRI not only in the evaluation of a residual mass but in the judgment of recurrence after treatment of such patients.
authors.affiliation: Department of Internal Medicine, Heisei Memorial Hospital, Kashihara, Nara, Japan. yyama@mx5.canvas.ne.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Taoka
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Nakamine
mesh_terms: D000368:Aged; D044466:Asian People; D005260:Female; D006801:Humans; D007564:Japan; D008223:Lymphoma / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging; D018365:Neoplasm, Residual; D049268:Positron-Emission Tomography; D011859:Radiography; D012445:Sacrococcygeal Region / Q000000981:diagnostic imaging*