Prevalence of Lynch syndrome among patients with newly diagnosed endometrial cancers.
BACKGROUND
Lynch syndrome (LS) is a hereditary condition that increases the risk for endometrial and other cancers. The identification of endometrial cancer (EC) patients with LS has the potential to influence life-saving interventions. We aimed to study the prevalence of LS among EC patients in our population.


METHODS
Universal screening for LS was applied for a consecutive series EC. Tumor testing using microsatellite instability (MSI), immunohistochemistry (IHC) for mismatch-repair (MMR) protein expression and MLH1-methylation analysis, when required, was used to select LS-suspicious cases. Sequencing of corresponding MMR genes was performed.


RESULTS
One hundred and seventy-three EC (average age, 63 years) were screened. Sixty-one patients (35%) had abnormal IHC or MSI results. After MLH1 methylation analysis, 27 cases were considered suspicious of LS. From these, 22 were contacted and referred for genetic counseling. Nineteen pursued genetic testing and eight were diagnosed of LS. Mutations were more frequent in younger patients (<50 yrs). Three cases had either intact IHC or MSS and reinforce the need of implement the EC screening with both techniques.


CONCLUSIONS
The prevalence of LS among EC patients was 4.6% (8/173); with a predictive frequency of 6.6% in the Spanish population. Universal screening of EC for LS is recommended.
Pathology, Alicante University Hospital, Alicante, Spain ; Research Laboratory, Alicante University Hospital, Alicante, Spain.
Cecilia
C
Egoavil
Cristina
C
Alenda
Adela
A
Castillejo
Artemio
A
Paya
Gloria
G
Peiro
Ana-Beatriz
AB
Sánchez-Heras
Maria-Isabel
MI
Castillejo
Estefanía
E
Rojas
Víctor-Manuel
VM
Barberá
Sonia
S
Cigüenza
Jose-Antonio
JA
Lopez
Oscar
O
Piñero
Maria-Jose
MJ
Román
Juan-Carlos
JC
Martínez-Escoriza
Carla
C
Guarinos
Lucia
L
Perez-Carbonell
Francisco-Ignacio
FI
Aranda
Jose-Luis
JL
Soto
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000150:complications* / Q000453:epidemiology*; D019175:DNA Methylation; D053843:DNA Mismatch Repair; D016889:Endometrial Neoplasms / Q000150:complications* / Q000175:diagnosis; D005260:Female; D018095:Germ-Line Mutation; D006801:Humans; D007150:Immunohistochemistry; D053842:Microsatellite Instability; D008875:Middle Aged; D000070957:MutL Protein Homolog 1; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D009687:Nuclear Proteins / Q000235:genetics; D015995:Prevalence
D048868:Adaptor Proteins, Signal Transducing; C501486:MLH1 protein, human; D009687:Nuclear Proteins; D000070957:MutL Protein Homolog 1