Bone Involvement in Lymphoma: 36 Cases. An Argentinian Cooperative Study.
Authors: Dragosky Marta O , Alcaraz Susana , Annetta Isabel , Devotto Laura , Corzo Ariel , Luchetta Patricia , Marquez Marisa , Morgenfeld Eduardo 
Published: October 2019

Abstract
Abstract 5025

Background
Bone involvement in linfomas is not very frequent, usually reflects progression of the disease and bad prognosis. The WHO recognizes 4 groups of lymphomas involving bone: 1) single primary bone site, 2) multiple bone sites, without visceral involvement, 3) bone lesion with visceral or lymph node involvement, 4) soft tissue lymphoma with bone involvement. Primary bone lymphoma (PBL) constitutes 3-7% of malignant bone tumors and 2-3% of extranodal lymphomas, groups 1 and 2 belong to this type. They are characterized by lytic lesions, predominant in metadiaphysis, with aggressive periosteal reaction and presence of soft tissue mass. The secondary affectation of bone has been described in 15 to 25 % of the linfomas in progression. Radiological studies, Scintigraphy, CT, MRI and PET allow to delimit extension.

Objective
To make a retrospective study of the clinical aspects, treatment and evolution of patients with lymphoma and bone involvement.

Methods
In a database from hemato-oncological patientes, 36 patients were studied: 30 Non Hodgkin Lymphoma (NHL):83, 33 % and 6 Hodgkin's Lymphoma (HL): 16, 66 % .

Results
Bone involment was found in 32 cases at diagnosis and 4 in relapse.

Characteristics of the LNH
B Lineage: 28 cases, T: 2. High grade 22 cases: 18 large cells B, 2 large cells T, 2 plasmoblastic; low grade: 7 small lymphocytic, 1 lymphoplasmocytic. Bone locations were multiple in 26 cases and localized in 10: 3 femur, 2 humerus, 1 tibia, 4 vertebral column (4 dorsal vertebrae, 1 lumbar).
Mean age: 49, 44 (20-86) years. Gender: M/F: 16/14. Stages: I: 26, 6 %, II: 16, 66 %, III: 10 %, IV: 46, 66 %. B symptoms in 25 %. Bone marrow involvement: 13, 88 %.
Symptoms: pain 40 %, pain and tumor in 13, 33 %, pain and lymph nodes: 16, 66%, tumor
(soft tissue involvement): 33,33%, pathological fracture: 10 %, paraplegia: 6,66%.
HIV positive 5 cases, (3 large cells B, 2 plasmoblastic), 2 maxilla, 2 mandible, 1 humerus.
Treatment: Chemotherapy (CT) in 28 patients), CHOP in 14, CVP 4, R-CHOP 3, EPOCH 2, ESHAP 2, CNOP, CAVPE, Fludara/CFM 1. 16 patients CT and Radiotherapy (RT), and 2 only RT. Evolution: 17 in complete response (RC), 6 dead, 6 without follow-up, 1 in treatment. Follow-up: 3-133 months, average: 44, 22.

Characteristics of the patients with LH
4 nodular sclerosis, 2 mixed cellularity. Mean age: 31, 33 (21-37) years, stage IV in all; 3 bone involvement at diagnosis and 3 at relapse. Treatment: CT: ABVD: 4, BEACOPP 1, ESHAP 1.RT in 4. Autologous bone marrow transplant: 1.Evolution: 2 in RC, 2 dead, 2 in relapse, 1 in treatment.

Conclusions
Our population shares the criteria described in other series: LNH's predominance, aggressive histologies, predominant symptoms: pain and local tumor, with involvement of soft tissues. Adverse prognostic factors were stage IV and location in maxilla (33, 33% dead). Combined treatment: CT and RT allowed better results. With an average follow- up of 44,22 months, 17 patients with LNH remain in RC, stage I: 87,5 % RC. Patients HIV positive had a bad prognosis, CR only 1, follow up 26 months. Bone involvement in HL was associated with advanced disease (stage IV) and bad prognosis, 33, 3 % RC, follow up: 4-72 months, average: 35, 5.

Disclosures
No relevant conflicts of interest to declare.