Primary mediastinal B-cell lymphoma - metabolic and anatomical features in 18FDG-PET/CT and response to therapy

• Published in: Contemporary oncology (Poznań, Poland) Poland), 2016-01, Vol.20 (4), p.297-301
• Main Author: paper, Original
• Format: Article
• Language: English
• Subjects: diffuse/radionuclide imaging; large B-cell; lymphoma; Original Paper; tomography; X-ray computed mediastinal neoplasms/radiography
• ISSN: 1428-2526; 1897-4309
• DOI: 10.5114/wo.2016.61849

Aim of the study: Determining the role of PET/CT imaging in the evaluation of treatment efficacy in primary mediastinal B-cell lymphoma (PMBCL). Material and methods: Retrospective analysis of seven PMBCL patients, treated at the University Hospital in Krakow, with interim PET/CT after the third course of chemo-immunotherapy. The analysis was based on the calculation of exact tumour volume and metabolic activity, compared with initial values (directly after diagnosis). Results: Patients (five females, two males, average age 26.2 years, range 18-40 years), in clinical stage IIBX at diagnosis, were treated with eight cycles of R-CHOP-14 regimen, with radiotherapy consolidation (7/7) and central nervous system prophylaxis (6/7). The observed decrease in tumour volume between the initial staging and the interim PET ranged 72-89%. The mean [increment]SUV max reduction between initial (when available) and interim PET was 87% (range 84-89%). In 3/7 cases in the interim PET/CT, the uptake of the tumour was higher than the liver (Deauville Criteria score 4-5), and in 4/7 it was lower than the liver but higher than mediastinal blood pool structures (score 3 according to Deauville Criteria). After a median follow-up of 58 months - OS and EFS is 100%. Conclusions: The excellent clinical outcome in the study group corresponds with very good metabolic and volumetric response in the interim PET. The [increment]SUVmax seems to be easier in implementation and has a more significant impact than other measurements.