Utility of serum free light chain measurements in multiple myeloma patients not achieving complete response to therapy
Menée à partir de données portant sur 449 patients atteints d'un myélome multiple récemment diagnostiqué et dont la réponse au traitement initial est incomplète, cette étude évalue l'intérêt de doser le niveau sérique des chaînes légères libres des immunoglobulines pour établir un pronostic
Normalization of the serum-free light-chain ratio (FLCr) with the absence of bone marrow monoclonal plasma cells following achievement of a complete response (CR) to therapy denotes a stringent CR in multiple myeloma (MM), and is associated with improved overall survival (OS). However, its value in patients achieving <CR is not clear. We hypothesized that patients achieving a normalization of FLCr with initial therapy of MM will have an improved outcome, even in the absence of a CR. We retrospectively evaluated 449 patients with newly diagnosed MM with measurable disease at baseline, who did not achieve a CR with initial therapy. One hundred and fifty-three patients (34%) had a normal FLCr, whereas 296 (66%) had an abnormal ratio. Patients with a normal FLCr had a longer progression-free survival (29 vs 16 months, P<0.001) and OS (91 vs 58 months, P<0.001). Normalization of FLCr retained its prognostic value in a multivariable model. Our results suggest an important role for sFLC measurement in disease monitoring even in patients who achieve only a partial response to therapy. Obtaining a normal FLCr confers a favorable prognosis independent from other factors, supporting the inclusion of sFLC in all levels of response criteria.
Leukemia , résumé, 2014