P1128: CLINICAL FEATURES AND OUTCOME OF PATIENTS WITH CASTLEMAN DISEASE: A SPANISH MULTICENTRIC STUDY OF 134 PATIENTS FROM GELTAMO

Background: Castleman disease (CD) is a heterogeneous rare disorder, characterized by lymph node enlargement with a common histopathological spectrum. This disease comprises the subtypes unicentric (UCD), HHV-8 multicentric CD (HHV-8 MCD), POEMS-asociated MCD (POEMS MCD) and idiopathic multicentric CD (iMCD).2 Whereas UCD is a localized reversible disease, the other three are systemic diseases with multiple lymphadenopathies. The TAFRO (thrombocytopenia, anasarca, fever, reticulin myelofybrosis, organomegaly) syndrome is an aggressive form of iMCD. Each CD subtype has different clinical features, prognosis and treatment. Aims: This study aims to study a large series of patients diagnosed with CD to describe the clinical and biological characteristics, as well as the outcome, of the different CD subtypes. Methods: Multicentric retrospective study which includes patients diagnosed with different subtypes of CD in 19 Spanish hospitals from 2006 to 2020. Clinical and biological data were retrieved from the clinical records. The project has been approved by the Ethical Committee of Germans Trias I Pujol Hospital (PI-20-103). Statistical analyses were performed using SPSS v24.0 (IBM, Somer, NY). Results: One hundred and thirty-four patients with available data were included; 47 with UCD and 87 with any of the 3 subtypes of MCD. The median follow-up was 3.4 years. The main clinical and biological characteristics of the 4 CD subtypes are shown in Table 1 and differences in OS in figure 1. Most patients with HHV-8 MCD were HIV-infected (73%); median CD4 lymphocyte count 0.229x109/L (range: 0.016, 1.2) and 46% of them had concomitant or prior Kaposi’s sarcoma. Three iMCD patients had TAFRO. All patients with UCD were treated with surgery. Most patients with HHV-8 MCD were treated at front-line with rituximab (69%) or polychemotherapy plus rituximab (21%). Patients with iMCD were treated with anti-IL-6 (25%), polychemotherapy (25%), rituximab (25%) and steroids (25%). Treatment of POEMS MCD was also diverse; 3 patients received lenalidomide plus dexamethasone, 2 polychemotherapy, 1 anti-IL-6 and 1 auto SCT (3 patients unrecorded). Eleven patients (8.2%) had concomitant or evolved to lymphoma (2 UCD, 2 iMCD and 7 HHV-8 MCD). Thirty-two patients are dead (20 HHV8-MCD, 7 iMCD, 2 UCD, 3 POEMS), 6 of them from CD (4 HHV8-MCD, 2 iMCD). Table 1. - Main clinical and biological characteristics of the CD subtypes Variable UCD (n=47) iMCD (n=24) HHV8-MCD (n=52) POEMS (n=11) TOTAL (n=134) p value Male gender, % 36 46 90 36 59 <0.001 Age, median (range) 40 (5, 84) 47 (10, 82) 47 (25, 88) 64 (30, 78) 47 (5, 88) 0.154 ECOG<2, n (%) 36/38 (95) 13/19 (68) 24/39 (62) 5/8 (63) 78/104 (75) 0.005 Bulky mass, n (%) 3/41 (7) 0/19 1/41 (2) 0/9 4/110 (4) 0.422 B symptoms, n (%) 4/41 (10) 6/17 (35) 31/41 (76) 3/9 (33) 44/108 (41) <0.001 Hemoglobin g/L, median (range) 135 (74, 990) 132 (40, 355) 106 (43, 332) 144 (83, 172) 126 (40, 990) <0.001 Leukocytes x10 9 /L, median (range) 7.1 (3.8, 21.1) 7.2 (2, 13.2) 6.3 (0.5, 23.7) 7.9 (2.4, 23) 6.7 (0.5, 23.7) 0.075 Platelets x10 9 /L, median (range) 247(67, 483) 241 (13.5, 501) 190.5 (3.5, 461) 467 (1.4, 560) 232 (1.4, 560) 0.05 High LDH, n (%) 2/35 (6) 7/16 (44) 6/41 (15) 0/9 15/101 (15) 0.002 High Ferritin, n (%) 1/24 (4) 2/9 (22) 19/29 (66) 0/6 22/68 (32) <0.001 High Beta-2 microglobulin, n (%) 1/15 (7) 4/11 (36) 20/26 (77) 4/5 (80) 29/57 (51) <0.001 Low albumin, n (%) 3/35 (9) 6/14 (43) 19/39 (49) 2/8 (25) 30/96 (31) 0.002 Image:Summary/Conclusion: Castleman Disease subtypes have different characteristics and outcomes. First-line treatment is heterogeneous in MCD subtypes pointing a need for national guidelines.