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PET may contribute to the management of patients with low-grade follicular NHL. For the other low-grade lymphoma subtypes, the role of PET is less evident. Further studies using PET to evaluate the results of treatment or to diagnose disease recurrence are warranted in low-grade follicular NHL.

A residual mass after treatment of lymphoma is a clinical challenge, because it may represent vital tumor as well as tissue fibrosis. Metabolic imaging by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) offers the advantage of functional tissue characterization that is largely independent of morphologic criteria. We compared18F-FDG PET to computed tomography (CT) in the posttreatment evaluation of 54 patients with Hodgkin’s disease (HD) or intermediate/high-grade non-Hodgkin’s lymphoma (NHL). Residual masses on CT were observed in 13 of 19 patients with HD and 11 of 35 patients with NHL. Five of 24 patients with residual masses on CT versus 1 of 30 patients without residual masses presented a positive18F-FDG PET study. Relapse occurred in all 6 patients (100%) with a positive 18F-FDG PET, 5 of 19 patients (26%) with residual masses on CT but negative 18F-FDG PET, and 3 of 29 patients (10%) with negative CT scan and18F-FDG PET studies (P ≤ .0001). We observed a higher relapse and death rate in patients with residual masses at CT compared with patients without residual masses at CT (progression-free survival at 1 year: 62 ± 10 v88 ± 7%, P = .0045; overall survival at 1 year: 77 ± 5 v 95 ± 5%, P = .0038). A positive18F-FDG PET study was even more consistently associated with poorer survival: compared with patients with a negative18F-FDG PET study, the 1-year progression-free survival was 0% versus 86% ± 5% (P < .0001) and the 1-year overall survival was 50% ± 20% versus 92% ± 4% (P < .0001). The detection of vital tumor by 18F-FDG PET after the end of treatment has a higher predictive value for relapse than classical CT scan imaging (positive predictive value: 100% v42%). This could help identify patients requiring intensification immediately after completion of chemotherapy. However,18F-FDG PET mainly predicts for early progression but cannot exclude the presence of minimal residual disease, possibly leading to a later relapse.

Our data suggest the potential of (18)F-FDG PET to detect preclinical relapse in patients with HD. This could help identify patients requiring salvage chemotherapy at the time of minimal disease rather than at the time of clinically overt relapse. Further studies are warranted to determine the impact of PET on treatment management and outcome. In fact, the aim of follow-up procedures is not only to detect preclinical relapse but mainly to obtain better results by starting salvage treatment earlier. A cost-benefit analysis will also be necessary before (18)F-FDG PET can be used routinely in the follow-up of patients with HD.

18F-FDG-PET is a useful tool for evaluating children with lymphomas. Large prospective studies are needed to appreciate its real impact on patient management.

Summary:A 37-year-old man with acute myeloblastic leukemia in first remission developed ulcerative colitis and bronchiolitis obliterans organizing pneumonia (BOOP) 7 months after bone marrow transplantation (BMT) from an HLA-matched brother who suffered from severe Crohn's disease. BOOP occurred 20 days after idiopathic interstitial pneumonia, in the context of severe ulcerative colitis. Lung and colon biopsies showed no signs of CMV infection or GVHD. The patient was treated with oral methylprednisolone 1 mg/kg/day and his clinical status and chest X-ray improved slowly. Remarkably, the symptoms of colitis also resolved with prednisone therapy and he is now symptom-free. We hypothesize that ulcerative colitis may have been transmitted from donor to recipient (adoptive autoimmunity) and that it was complicated by BOOP. However, other factors such as CMV may have contributed to the occurrence of BOOP. Keywords: allogeneic bone marrow transplantation; autoimmune diseases; ulcerative colitis; BOOP; adoptive autoimmunity Bronchiolitis obliterans organizing pneumonia (BOOP) is a rare cause of diffuse infiltrative lung disease. It may be idiopathic or occur in association with infections, drugs or miscellaneous neoplastic or inflammatory diseases. The first case of BOOP following bone marrow transplantation (BMT) was described in 1990. 1 Since then, six additional cases of BMT-associated BOOP have been reported (Table 1), including two successive episodes in a single patient undergoing two BMT procedures. 2-4 BOOP has also been described in several patients with inflammatory bowel disease. 5 We report a new case of BMT-associated BOOP which developed in the recipient of a marrow transplant from a donor who suffered from Crohn's disease. As the patient simultaneously developed ulcerative colitis and BOOP about 6 months after BMT, this observation could Correspondence: Dr Y Beguin, University of Liège, Department of Hematology, CHU Sart-Tilman, 4000 Liège, Belgium Received 15 August 1997; accepted 11 November 1997 constitute a case of adoptive autoimmunity in which transmission from donor to recipient of inflammatory bowel disease could have contributed to the pathogenesis of BMTassociated BOOP. Case reportThe patient, a 37-year-old man with acute myeloblastic leukemia in first remission, received a genotypically HLAidentical BMT from his brother in March 1995. The donor was negative for cytomegalovirus (CMV) on serology but had suffered from severe Crohn's disease for the past 15 years, which was treated with sulfasalazine and azathioprine. The latter was stopped 3 weeks before the transplant. The recipient was positive for CMV. Pre-transplant pulmonary function tests were normal. Conditioning consisted of cytarabine 12 g/m 2 , cyclophosphamide 120 mg/kg and single dose total body irradiation (TBI) 8 Gy. Graft-versushost disease (GVHD) prophylaxis was carried out with short methotrexate and cyclosporine (CsA).The initial post-transplant course was complicated by grade 1 acute skin GVHD that resolved after increasing t...

No abstract

A residual mass after treatment of lymphoma is a clinical challenge, because it may represent vital tumor as well as tissue fibrosis. Metabolic imaging by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) offers the advantage of functional tissue characterization that is largely independent of morphologic criteria. We compared18F-FDG PET to computed tomography (CT) in the posttreatment evaluation of 54 patients with Hodgkin’s disease (HD) or intermediate/high-grade non-Hodgkin’s lymphoma (NHL). Residual masses on CT were observed in 13 of 19 patients with HD and 11 of 35 patients with NHL. Five of 24 patients with residual masses on CT versus 1 of 30 patients without residual masses presented a positive18F-FDG PET study. Relapse occurred in all 6 patients (100%) with a positive 18F-FDG PET, 5 of 19 patients (26%) with residual masses on CT but negative 18F-FDG PET, and 3 of 29 patients (10%) with negative CT scan and18F-FDG PET studies (P ≤ .0001). We observed a higher relapse and death rate in patients with residual masses at CT compared with patients without residual masses at CT (progression-free survival at 1 year: 62 ± 10 v88 ± 7%, P = .0045; overall survival at 1 year: 77 ± 5 v 95 ± 5%, P = .0038). A positive18F-FDG PET study was even more consistently associated with poorer survival: compared with patients with a negative18F-FDG PET study, the 1-year progression-free survival was 0% versus 86% ± 5% (P &lt; .0001) and the 1-year overall survival was 50% ± 20% versus 92% ± 4% (P &lt; .0001). The detection of vital tumor by 18F-FDG PET after the end of treatment has a higher predictive value for relapse than classical CT scan imaging (positive predictive value: 100% v42%). This could help identify patients requiring intensification immediately after completion of chemotherapy. However,18F-FDG PET mainly predicts for early progression but cannot exclude the presence of minimal residual disease, possibly leading to a later relapse.