Clinical Characteristics and Outcome of Primary AL Amyloidosis in Greece.
Authors: Michail Michalis , Kastritis Efstathios , Delimpassi Sossana , Kyrtsonis Marie Christine , Michali Evridiki , Anagnostopoulos Nicolaos , Zervas Konstantinos , Katodritou Eirini , Panagiotidis Panagiotis , Tzenou Natalia , Pangalis Gerassimos , Dimopoulos Meletios Athanasios 
Published: October 2019

Introduction: Primary systemic amyloidosis (AL) is a clonal plasma cells disorder characterized by deposition of amyloid fibrils derived from abnormal light chains, leading to multiorgan involvement and failure. There is no information regarding the clinical, laboratory, treatment characteristics and outcome of such patients in Greece. We performed a retrospective analysis in order to clarify these issues.

Patients and Methods: Diagnosis of primary AL amyloidosis was based on positive Congo red staining, immunohistochemistry and the presence of typical clinical and laboratory features. Definition of organ involvement and treatment response was based on established criteria (Gertz et al Am J Hematol 2005).

Results: between 1995 and 2007, we identified 109 patients with previously untreated systemic AL amyloidosis. Median age was 66.3 years; 51% were males and lambda-light chain was involved in 74% of patients. Bone marrow biopsy stained positive for Congo-red in 56.5%, immunohistochemical staining was performed in 80 cases: 63 (78.75%) stained positive for λ and 17 for κ light chains. A monoclonal protein by immunofixation was found in the serum and/or urine of 97 (87%) patients. More than 10% bone marrow plasma cells were found in 65%. B2microglobulin was elevated in 36% of patients (median value 2.8 mg/l). The most frequent symptoms at presentation were fatigue and weakness (81%). Heart was involved in 66 (59%), kidney in 79 (71%), liver in 21(19%), GI tract in 17 (16%) and soft tissue in 35 (32%) patients respectively. Symptoms of peripheral and/or autonomic neuropathy were present in 38 (35%) patients. More than two organs were involved in 50 patients (45%). Primary treatment with high-dose dexamethasone based regimens (VAD or pulse Dexamethasone) was used in 45% while 37% of patients were treated with melphalan and prednisone. Six patients (5%) were treated upfront with high dose melphalan and ASCT while another 6 patients were transplanted at a later stage of their disease. Hematologic response was achieved in 50 (46%) including 16 (14.5%) patients who achieved a CR. Organ responses were seen in 32 (29%) patients: 4 had cardiac, 21 renal and 7 liver response respectively while 11 patients had subjective improvement of peripheral or autonomic neuropathy. Median survival from initiation of treatment was 61 months and the 5 year-survival was 44%. Patients with heart involvement or with more than 2 affected organs had a worse prognosis. Survival was significantly longer for patients who responded to primary treatment than for those who did not (p=0.018).

Conclusions: Greek patients with AL amyloidosis share the same characteristics with that of patients from other reported studies. Hematologic responses were noted in one-half and organ responses in one-third of patients. Prognosis depended primarily on the presence of heart involvement and on the lack of response to treatment.