Clinical course and prognosis of non-secretory multiple myeloma.
OBJECTIVE
To determine the prognosis of patients with non-secretory myeloma.


METHODS
We studied 124 patients diagnosed with multiple myeloma who had no monoclonal protein detected on serum and urine immunofixation at diagnosis and on all subsequent follow-up testing (non-secretory myeloma). The overall survival (OS) of patients with non-secretory myeloma was compared with 6953 patients with typical myeloma seen during the same time period in whom a monoclonal protein was detected at the time of diagnosis.


RESULTS
One hundred and twenty-four patients met criteria for non-secretory multiple myeloma. The median follow-up was 102 months (range, 1-204 months). The median progression-free survival with initial therapy was 28.6 months, and the median OS was 49.3 months. There was a significant improvement in OS since 2001; median survival 43.8 months (prior to 2001) vs. 99.2 months (2001-2012), P < 0.001. OS was superior in patients with a normal baseline FLC ratio (n = 10) compared to patients with an abnormal ratio (n = 19), medians not reached in both groups. Prior to 2001, OS was similar in non-secretory myeloma (n = 86) and secretory myeloma (n = 4011), median 3.6 vs. 3.5 yr, respectively, P = 0.63. However, among patients diagnosed between 2001 and 2012, OS was superior in non-secretory myeloma (n = 36) compared to secretory myeloma (n = 2942), median 8.3 vs. 5.4 yr, respectively, P = 0.03.


CONCLUSIONS
Non-secretory myeloma is an uncommon subtype of multiple myeloma. In the last decade, there has been an improvement in the survival of non-secretory myeloma and appears superior to secretory myeloma.
Mayo Medical School, Mayo Clinic, Rochester, MN, USA.
Sagar S
SS
Chawla
Division of Hematology, Mayo Clinic, Rochester, MN, USA.
Shaji K
SK
Kumar
Division of Hematology, Mayo Clinic, Rochester, MN, USA.
Angela
A
Dispenzieri
Division of Epidemiology, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA.
Alexandra J
AJ
Greenberg
Division of Biostatistics, Mayo Clinic, Rochester, MN, USA.
Dirk R
DR
Larson
Division of Hematology, Mayo Clinic, Rochester, MN, USA.
Robert A
RA
Kyle
Division of Hematology, Mayo Clinic, Rochester, MN, USA.
Martha Q
MQ
Lacy
Division of Hematology, Mayo Clinic, Rochester, MN, USA.
Morie A
MA
Gertz
Division of Hematology, Mayo Clinic, Rochester, MN, USA.
S Vincent
SV
Rajkumar
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D015870:Gene Expression; D006801:Humans; D007145:Immunoglobulin kappa-Chains / Q000097:blood / Q000235:genetics; D007146:Immunoglobulin lambda-Chains / Q000097:blood / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality*; D009194:Myeloma Proteins / Q000235:genetics* / Q000378:metabolism; D011379:Prognosis; D016019:Survival Analysis
D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; D009194:Myeloma Proteins
myeloma; prognosis; therapy