PET/CT diagnostic value in suspicion of palatine tonsils’ lymphoma recurrence

Introduction: Diffuse large B-cell lymphoma (DLBCL) is a non-homogenous group of neoplasms of the lymphatic system in terms of morphology, genetics, and clinical aspects. The follow-up of patients treated for lymphoma includes the following examinations: clinical, laboratory, and imaging. According to the recommendation of the National Comprehensive Cancer Network (NCCN) from 2020, the observation of patients with DLBCL is mostly based on the PET/CT examination with 18F-FDG, especially when suspecting the extranodal lymphoma recurrence. Aim: The aim of the study was to define the predictive value of the PET/CT examination in the evaluation of the recurrence of DLBCL in the palatine tonsils. Material and methods: The analysis of the medical documentation of patients treated in our Department was performed. Research material included patients with suspicion of local recurrence of DLBCL in the palatine tonsils. Thirty-three patients were included in the study: 22 women and 11 men. The age range was 23–73 years with a mean of 53 years. Results: The confirmation of the local recurrence of DLBCL in the histological examination was obtained in 11 patients – 7 women and 4 men aged 58–73 years (μ= 65.4). SUVmax in the palatine tonsil in those patients ranged: for the right tonsil 3.6–9.5 (μ=6.0), and for the left tonsil 3.8–9.5 (μ = 6.1). The second group of the patients did not present any local recurrence of DLBCL in the palatine tonsils. The histological diagnosis was chronic tonsillitis. The age of those patients ranged from 23 up to 73 years (μ = 43.1 years). SUVmax ranged: for the right palatine tonsil 2.8-27.7 (μ = 8.62), for the left palatine tonsil 3.8–27.4 (μ = 8.60). The sensitivity of PET/CT in the recurrence assessment in our study was 100%, while the specificity was 33.3%. The additional predictive value was 0.33.