finds a retrospective cohort study of the International Myeloma Working Group. That figure may be even higher today because more than 90% of patients in the study – the largest yet to look at outcome predictors in this population – were treated in the era before novel therapies became available.
Investigators led by Saad Z. Usmani, MD, director/chief of plasma cell disorders and director of clinical research (hematologic malignancies) at the Levine Cancer Institute/Atrium Health in Charlotte, N.C., studied 7,291 patients with newly diagnosed multiple myeloma who were up to 75 years old and eligible for high-dose melphalan and autologous stem cell transplant. The patients were treated in clinical trials in 10 countries.
Compared with counterparts who did not achieve complete response 1 year after diagnosis, patients who did had better median progression-free survival (3.3 vs. 2.6 years; P less than .0001) and median overall survival (8.5 vs. 6.3 years; P less than .0001), according to study results report in Blood Cancer Journal.
The investigators next performed multivariate analyses to assess clinical variables at diagnosis associated with 10-year survival as compared with 2-year death.
Results here indicated that patients were less likely to be alive at 10 years if they were older than 65 years (odds ratio for death, 1.87; P = .002); had an immunoglobulin A isotype (OR, 1.53; P = .004); had a low albumin level, defined as less than 3.5 g/dL (OR, 1.36; P = .023); had an elevated beta2-microglobulin level, defined as at least 3.5 mg/dL (OR, 1.86; P less than .001); had a higher serum creatinine level, defined as at least 2 mg/dL (OR, 1.77; P = .005); had a lower hemoglobin level, defined as less than 10 g/dL (OR, 1.55; P = .003); or had a lower platelet count, defined as less than 150,000/μL (OR, 2.26; P less than .001).
Cytogenetic abnormalities did not independently predict long-term survival, but these abnormalities were obtained only by conventional band karyotyping and were not available for some patients.
Overall, the cohort had a relative survival of about 0.9 when compared with the matched general population. With follow-up out to about 20 years, the cure fraction (proportion achieving or exceeding expected survival when compared with the matched general population) was 14.3%.
Identification of early complete response as a predictor of long-term survival “underscores the importance of depth of response as we explore novel regimens for newly diagnosed [multiple myeloma] along with [minimal residual disease] endpoints,” Dr. Usmani and his colleagues wrote while acknowledging that the patients studied were a selected group eligible for transplant and treated on trials.
Recent therapeutic advances “have reignited the debate on possible functional curability of a subset MM patients,” they noted. “[T]here are perhaps more effective drugs and drug classes in the clinician’s armamentarium than [were] available for MM patients being treated in the 1990s or even early 2000s. This may mean that the depth of response after induction therapy may continue to improve over time, potentially further improving the PFS/OS of [the] biologic subset who previously achieved [partial response] yet had good long-term survival.”
Dr. Usmani disclosed that he is a consultant for AbbVie, Amgen, BMS, Celgene, Janssen, Takeda, Sanofi, and SkylineDx; receives speaker’s fees for Amgen, Celgene, Janssen, and Takeda; and receives research funding from Amgen, Array Biopharma, BMS, Celgene, Janssen, Pharmacyclics, Sanofi, and Takeda.
SOURCE: Usmani SZ et al. Blood Cancer J. 2018 Nov 23;8(12):123..