Mediastinal bulky tumour in Hodgkin's disease and prognostic value of positron emission tomography in the evaluation of post-treatment residual masses.

Among the 193 patients (82 female, 111 male) treated primarily for Hodgkin's disease at our clinic between 1990 and 2001 and followed up until 2003, 42 (22%) had mediastinal bulky tumours (MBTs) by the Cotswolds criteria. The rate of MBT diagnosis was significantly greater in the early stage of the disease, these patients were younger and--in contrast to the other group--they all received combined therapy. No significant differences were found in the overall and relapse-free survival rate in the two groups, but relapse and death rates were lower in the patients with bulky tumours. Of the total number of patients, 27 underwent a total of 31 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) examinations, mainly for the evaluation of post-treatment residual mass viability. In the 12 positive cases, the majority of patients received further therapy. During the mean follow-up time of 58 months (range 5-98 months) after obtaining negative results, progression of the disease was found in 2 cases 14 and 23 months later, respectively. Based on our results, we conclude that FDG-PET examinations show a good correlation with clinical follow-up results.