Characteristics of T- and NK/T-cell lymphomas with different pathological subtypes on 18F-FDG PET/CT

Abstract

Objective To investigate the imaging presentation of T- and NK/T-cell lymphomas with different pathology subtypes on 18F-FDG PET/CT. Methods A total of 95 patients (66 males, 29 females, average age 38.42 years) with T- and NK/T-cell lymphoma proved by pathology from June 2006 to February 2016 were retrospectively analyzed. 18F-FDG uptake (SUVmax), nodal invasion, nodal distribution, extra-nodal involvement and staging were compared among 7 pathological subtypes of T- and NK/T-cell lymphomas. One-way analysis of variance, Fisher exact test and Kruskal-Wallis H test were used for data analysis. Results There were significant differences in terms of 18F-FDG uptake, nodal invasion, nodal distribution, extra-nodal involvement and staging among different pathological subtypes of T- and NK/T-cell lymphomas (F=2.937, P<0.05; Fisher exact test, all P<0.01; H=19.883, P<0.01). NK/T-cell lymphoma was found to be prone to invade the nasal cavity and nasopharynx, enteropathic type T-cell lymphoma was specific to the intestine, and subcutaneous panniculitis-like T-cell lymphoma presented with subcutaneous infiltration. All those 3 subtypes were quite specific in their extra-nodal involvement. Most patients with angioimmunoblastic T-cell lymphoma (ATCL), peripheral unspecified T-cell lymphoma (PUTCL) and T immunoblastic lymphoma (TIBL) presented as stage Ⅳ disease. Widespread lymph node disease associated with splenic, parotid and serous membrane involvement were often seen in ATCL patients (most commonly to involve the parotid glands and serous membrane among the 7 subtypes). Nodal involvement was found in PUTCL patients, but extranodal involvement was rather non-specific. TIBL had a non-specific pattern of nodal involvement with low 18F-FDG uptake, lower than ATCL and the other 5 subtypes. Anaplastic large cell lymphoma subtypes had the highest 18F-FDG uptake when compared with the other 6 subtypes, but were less often to manifest as stage Ⅳ disease despite their preponderance for marrow and nodal infiltration. Conclusion Different pathological subtypes of T- and NK/T-cell lymphoma manifest different imaging presentations on 18F-FDG PET/CT, which are useful for understanding their biological characteristics. Key words: Lymphoma, T-cell; Natural killer T-cells; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose