Revisiting Diagnostic performances of serum erythropoïetin level and JAK2 mutation for polycythemias: analysis of a cohort of 1090 patients with red cell mass measurement.

We assessed the diagnostic performances of erythropoietin and JAK2 mutations in 1,090 patients with suspected polycythemia who were referred for red cell mass (RCM) measurement. In patients with a high haematocrit and/or haemoglobin level, a low erythropoietin level (<=3·3 mUI/ml) and JAK2 mutation showed comparable positive predictive value (PPV) for true polycythemia (RCM>=125%), 92·1% and 90% respectively. A very-low erythropoietin level (<=1·99 mUI/ml) had a PPV of 100% for polycythemia vera (PV) diagnosis. We confirmed the correlations between RCM, erythropoietin and JAK2 variant allelic frequency in PV patients. This study prompts the need to revisit the role of EPO in PV diagnostic criteria.

L'arrivée de l'immunothérapie dans le lymphome de Hodgkin.

IMMUNOTHERAPY OF HODGKIN LYMPHOMA: Classical Hodgkin lymphoma (HL) is a rare hematological cancer, affecting preferentially young adults. Using a risk-adapted approach, HL has become highly curable (>80%) with front-line chemotherapy in addition with radiotherapy, despite long term significant toxicity. Some patients are primary refractory or relapse after first-line chemotherapy, requiring high dose chemotherapy with serious side effects. Studies of the microenvironment from HL tissue reveal ineffective inflammatory and immune cell infiltrate surrounding Reed-Sternberg cells, involving the Programmed cell Death 1 (PD-1)/PD-ligand-1 checkpoint pathways. Recently, immune checkpoint inhibitors demonstrated high efficacy for relapsed and refractory patients, with a favorable safety profile but indeterminate long term outcome. Guidelines for nivolumab or pembrolizumab treatment in HL remain to be established.