Prognostic factors associated with progression of smoldering multiple myeloma to symptomatic form.
BACKGROUND
Smoldering multiple myeloma (SMM) presents a high risk of progression to symptomatic MM (sy-MM). Herein, we analyzed some predictors of development of sy-MM. In 144 patients with SMM, we also compared the risk of progression predicted by bone marrow plasma cell (BMPC) involvement on the bone marrow biopsy (BMB) versus bone marrow aspirates (BMA).


METHODS
From January 1980 to July 2010, 397 patients with SMM observed in 12 centers of the Multiple Myeloma GIMEMA (Gruppo Italiano Malattie EMatologiche dell'Adulto) Latium Working Group have been analyzed. At progression to sy-MM, the severity of clinical presentation was graded according to the need of intensive supportive care.


RESULTS
After a median follow-up of 135 months, the cumulative incidence of progression rates to sy-MM were 45%, 55%, and 75% at 10, 15, and 20 years, respectively. Hemoglobin ≤12.5 g/dL, monoclonal component ≥2.5 g/dL, and BMPC ≥60% were the only parameters negatively affecting the cumulative incidence of progression. In particular, 10 of 397 (2.5%) patients with BMPC ≥60% had a 5.6-fold increased risk of fast progression (within 2 years), which occurred with severe clinical manifestations in 62% of cases. BMB was more sensitive for the detection of BMPC involvement, even though BMA was a more reliable indicator of a rapid progression to sy-MM.


CONCLUSIONS
The highest risk of rapid evolution to sy-MM and the severity of clinical manifestation at the progression suggest that SMM patients with a BMPC ≥60% should be treated soon after diagnosis. Moreover, BMPC is a more reliable index for progression to sy-MM if assessed by BMA.
Department of Cellular Biotechnologies and Hematology, "Sapienza" University Polo Pontino, Rome, Italy.
Angela
A
Rago
Sara
S
Grammatico
Tommaso
T
Za
Anna
A
Levi
Sergio
S
Mecarocci
Agostina
A
Siniscalchi
Luca
L
De Rosa
Stefano
S
Felici
Velia
V
Bongarzoni
Anna Lina
AL
Piccioni
Giacinto
G
La Verde
Francesco
F
Pisani
Luca
L
Franceschini
Anna Lisa
AL
Paviglianiti
Tommaso
T
Caravita
Maria Teresa
MT
Petrucci
Valerio
V
De Stefano
Giuseppe
G
Cimino
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases; D001707:Biopsy, Needle; D001853:Bone Marrow / Q000473:pathology; D001854:Bone Marrow Cells / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis* / Q000473:pathology; D010950:Plasma Cells / Q000473:pathology*; D011379:Prognosis; D015996:Survival Rate; D055815:Young Adult