Abstract
e20068 Background: FL grade 3B (FL3B) is an aggressive subtype of FL with a distinct morphologic, cytogenetic and immunohistochemical profile that is associated with higher mortality compared to other subtypes of FL. FL3B is a rare disease, and data regarding its prognostication beyond grading is lacking. Recent data suggests that spleen and extranodal (EN) involvement on PET/CT predict early clinical failure in FL grades 1-3A[1]. We aimed to determine the incidence of spleen and EN involvement on PET/CT in FL3B, and whether these can predict EFS. Methods: Patients with untreated FL3B diagnosed between 2003-2016, with available pre-treatment PET/CT, were identified using the Mayo Clinic Lymphoma Database and the University of Iowa/Mayo Clinic Lymphoma SPORE database. 27 patients were included in this analysis. All but two patients received treatment with immunochemotherapy. Associations with outcomes were assessed using EFS, defined as disease progression, relapse, transformation, or death. Results: 11/27 (40.7%) of patients had EN involvement on PET/CT. The most common EN site was bone, in 8/27 (29.5%) of patients. Soft tissue involvement was present in 4/27 (14.8%) of patients. Liver, brain, and endometrial involvement were each noted once. 11/27 (40.7%) of patients had spleen involvement on PET/CT. Presence of bone involvement as detected on PET/CT was associated with lower EFS (p = 0.02). EN involvement was associated with a trend toward a lower EFS but statistical significance was not reached likely secondary to low numbers in this cohort. Results in the table are compared to results obtained from our analysis in patients with FL grade 1-3A[1]. Conclusions: Bone involvement on pre-treatment PET/CT in FL3B was associated with early clinical failure in this small cohort of 27 patients. EN involvement at diagnosis may also be associated with poorer outcomes. These findings are similar to our analysis of a large (n = 613) cohort of patients with FL grade 1-3A. These findings may aid in the prognostication of patients with newly diagnosed FL3B, to guide therapy in select higher risk patients. [Table: see text]
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
