PB2147 AL AMYLOIDOSIS IN THE CHILEAN PUBLIC HEALTH SYSTEM: A PENDING DEBT. MULTICENTER STUDY OF THE CHILEAN HEMATOLOGICAL COOPERATIVE GROUP (PANDA)
Authors: Vidal H. Lopez , Peña C. , Gonzalez J. T. , Donoso J. , Contreras C. , Vergara C. G. , Hojas R. , Soto P. , Correa G. , Valjalo R. , Ríos A. , Rojas C. 
Published: June 2019

Background:

Amyloidosis has an estimated incidence of 3‐14/1 million inhabitants/year is estimated, depending on the geographical area. While the whole world discusses about the new diagnostic and therapeutic tools, in Chile, and Latin America in general, we are far from that reality. There is little information about AL amyloidosis in Chile, consisting mainly on case reports. The largest report was in 2005, when where 11 cases were described.

Aims:

Characterize patients with AL amyloidosis in public health centers throughout the country.

Methods

Retrospective and descriptive multicenter study. The public centers part of the Chilean hematological cooperative group (PANDA) were asked to search in their databases to find patients diagnosed with AL amyloidosis. In all centers, the diagnosis of AL amyloidosis was made with a positive Congo red stain on tissue biopsy. Affected organs were determined by biopsy or according to the definition of Gertz et al. Epidemiological, clinical and laboratory characteristics were evaluated.

Results:

Data was collected from 42 patients of eight public health centers. The median age was 65 years, ranging from 22 to 84 years. The male to female ratio was 1: 0.75. 24% of the patients were diagnosed with localized AL amyloidosis; 64% presented with a lambda light chain clone; 47% of cases were associated with multiple myeloma (MM) and a 9% with non‐Hodgkin lymphoma (NHL) (Figure 1): 2 MALT lymphomas, 1 lymphoplasmacytic lymphoma, and a non‐characterized low grade B cell lymphoma. The most frequently involved organ was the kidney (76%), followed by the heart (48%). The analysis by group: 1.‐ Primary amyloidosis, 2.‐ MM‐associated amyloidosis, and 3.‐NHL‐associated AL amyloidosis showed no statistical difference between them. Regarding diagnostic tests, 100% reported having performed serum protein electrophoresis (sPEP), 69% serum immunofixation (sIFE) and 43% urine IFE. Serum Free light chains (sFLC) were performed in 31% of the patients, and echocardiogram on 74%. The most frequently performed biopsies were bone marrow (52%) and subcutaneous fat tissue (38%), being these samples diagnostic in 45% and 44% of cases respectively. Renal biopsy was performed in 33% of the cases, with a positive diagnosis in all of them. Treatment was heterogeneous: 17% received only palliative care, 17% were treated with bortezomib based therapy, 21% with cyclophosphamide, thalidomide, and dexamethasone (CTD), and 40% with melphalan based therapy. No patient received a bone marrow transplant. The median OS of the group was 19 months. The 3‐year OS was 38%, and the 5‐year OS 28%. There was no difference between patients with or without associated MM (5‐year OS of 22% vs 24%; p= 0.8), with or without use of novel agents (5‐yr OS of 15% vs 38%; p = 0,09), localized versus systemic amyloidosis (5‐yr OS of 36% vs 27%; p = 0,6) or with or without cardiac involvement (5‐yr OS of 25% vs 31%; p = 0.31).

Summary/Conclusion:

This is to our knowledge, the biggest experience published in Chile and Latin‐America on this topic. The scarce number of patients may be due to registry deficiency on our healthcare system. This is further favored by lack of clinical suspicion and reduced access to diagnostic tools. There are shortfalls in the diagnostic study and treatment of amyloidosis AL in our public health centers. It is important to obtain realistic, national results to initiate strategies to improve both early diagnosis and management of this pathology. Improving awareness is therefore crucial.