Microsatellite instability is an independent indicator of recurrence in sporadic stage I-II endometrial adenocarcinoma.
OBJECTIVE
The aim of this study was to define the prognostic role of microsatellite status in 65 stage I-II primary sporadic endometrioid endometrial adenocarcinoma (EEA) patients.


METHODS
Familiarity for neoplasia was ascertained in all patients on the basis of a questionnaire. Microsatellite status was assessed by matching normal and tumoral DNA probed for five dinucleotide repeats and one mononucleotide repeat marker. Microsatellite status was analyzed in relation to clinicopathologic characteristics of the patients and length of disease-free survival (DFS).


RESULTS
Eleven tumors (17%) of 65 had instability at two or more loci and were considered as unstable or microsatellite instability (MI). Tumors with no instability or instability at one locus were classified as microsatellite stable (MS). The percentage of MI was significantly higher in poorly than in well to moderately differentiated tumors (50% v 9%; P =.003). The 5-year DFS rate of MI patients was 63% (95% confidence interval [CI], 35% to 91%) versus 96% (95% CI, 91% to 101%) of MS patients (P =.0004). In multivariate analysis, only the presence of MI, stage II of disease, and depth of myometrial invasion greater than 50% retained independent prognostic roles.


CONCLUSIONS
The assessment of microsatellite status may provide useful information for preoperative prognostic characterization of stage I-II primary sporadic EEA patients in which more individualized treatment options can be attempted.
Fiumicino
S
S
Laboratory of Comparative Toxicology and Ecotoxicology, Istituto Superiore di Sanità, Rome, Italy.
Ercoli
A
A
Ferrandina
G
G
Hess
P
P
Raspaglio
G
G
Genuardi
M
M
Rovella
V
V
Bellacosa
A
A
Cicchillitti
L
L
Mancuso
S
S
Bignami
M
M
Scambia
G
G
D048868:Adaptor Proteins, Signal Transducing; D000230:Adenocarcinoma / Q000235:genetics*; D000367:Age Factors; D002352:Carrier Proteins; D016889:Endometrial Neoplasms / Q000235:genetics*; D005260:Female; D006801:Humans; D018895:Microsatellite Repeats / Q000235:genetics*; D008875:Middle Aged; D015999:Multivariate Analysis; D000070957:MutL Protein Homolog 1; D009363:Neoplasm Proteins / Q000032:analysis; D009364:Neoplasm Recurrence, Local; D009687:Nuclear Proteins; D011379:Prognosis
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C501486:MLH1 protein, human; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D000070957:MutL Protein Homolog 1