[Monoclonal gammopathies of undetermined significance and their progression over time. Retrospective study of 190 patients].
BACKGROUND
Monoclonal gammopathies of undetermined significance (MGUS) occur in up to 1% of persons aged 50 years or older. The risk of its progression to multiple myeloma or related disorders is also approximately 1% per year.


OBJECTIVE
Our study had two aims: to describe the risk of malignant progression of patients examined in our center for MGUS, and to identify predictors of this malignant progression.


METHODS
We retrospectively reviewed the medical records of patients with MGUS seen in our center from 1980 through 1995. Information about progression came either from the medical file or from responses to questionnaires sent to patients' general practitioners.


RESULTS
The study included 190 patients. Median follow-up was 84 months (range: 12-240 months). MGUS remained stable for 128 patients (67.37%), whose median follow-up was 96 months. Malignant transformations occurred in 41 patients (21.58%). The median interval from diagnosis of MGUS to diagnosis of a lymphoplasma cell proliferative disorder was 49 months. The cumulative probability of progression was 13.05% at 5 years and 25.14% at 10 years. The initial concentration of serum monoclonal protein was a significant predictor of progression (threshold value: 15 g/L).


CONCLUSIONS
The cumulative probability of progression in our study is higher than that observed elsewhere. Our results may well be biased by the short follow-up period and selective referrals.


CONCLUSIONS
The initial concentration of serum monoclonal protein is a significant predictor of malignant progression of MGUS.
Decaux
Olivier
O
Département de médecine de l'adulte, Service de médecine interne, Hôpital Sud, Rennes, France. olivdecaux@free.fr
Cuggia
Marc
M
Ruelland
Annie
A
Cazalets
Claire
C
Cador
Bérangère
B
Jego
Patrick
P
Grosbois
Bernard
B
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D019337:Hematologic Neoplasms / Q000453:epidemiology; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D008875:Middle Aged; D010265:Paraproteinemias / Q000175:diagnosis / Q000276:immunology / Q000503:physiopathology*; D018579:Patient Selection; D012189:Retrospective Studies; D013997:Time Factors
D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M