Canadian high risk endometrial cancer (CHREC) consortium: analyzing the clinical behavior of high risk endometrial cancers.
OBJECTIVE
The objective of this study is to analyze the clinical behavior of endometrial carcinomas by high risk(HR) histotype, including stage, overall survival, recurrence free survival and patterns of failure.


METHODS
This is a retrospective multi-institutional cohort study performed at 7 tertiary care centers across Canada between 2000 and 2012 and included: grade 3 endometrioid (EC3), endometrial serous cancer (ESC), clear cell carcinomas (CCC) and carcinosarcoma (CS). Clinicopathological and outcome data was collected.


RESULTS
1260 women with endometrial carcinoma with 1013 having staging procedures were identified; 398 EC3, 449 ESC, 236 CS and 91 CCC. 51.8% had lymphovascular space invasion (LVSI) and 18.5% had omental involvement with a statistically significant difference between tumor types (p=0.0005 and 0.0047 respectively); ESC had a significantly greater rate of omental involvement compared to EC3 (22% to 9%, p=0.0005). Within the entire cohort 49.3% were stage 1, 10.6% were stage 2, 27.4% were stage 3 and 12.7% were stage 4. Overall survival and recurrence free survival were significantly different between histotypes (p<0.0001) with CS having the worst outcome. Overall 31.5% of patients recurred. CS and ESC had a higher distant recurrence rate compared to EC3 (29.6%, 31.0% compared to 16.4%, p=0.0002 and p<0.001).


CONCLUSIONS
This study is one of the largest clinical cohorts of HR endometrial cancers. We have further clarified the impact of histotype and stage on recurrence and survival, and the high likelihood of distant recurrence. However, the differences are modest and risk prediction models will require additional molecular markers.
Division of Gynecologic Oncology, University of Manitoba, Canada.
Alon D
AD
Altman
Division of Gynecologic Oncology, University of Toronto, Canada.
Sarah E
SE
Ferguson
Biostatistics Department, Princess Margaret Cancer Centre, Canada; Division of Biostatistics, Dalla Lana School of Public Health, University of Toronto, Canada.
Eshetu G
EG
Atenafu
Department of Pathology and Laboratory Medicine, University of Calgary, Canada.
Martin
M
Köbel
Division of Gynecologic Oncology, CHUM-Hôpital Notre-Dame, Canada; Division of Gynecologic Oncology, University of British Columbia, Canada.
Jessica N
JN
McAlpine
Biostatistics Department, Princess Margaret Cancer Centre, Canada; Division of Biostatistics, Dalla Lana School of Public Health, University of Toronto, Canada.
Tony
T
Panzarella
Division of Gynecologic Oncology, McGill University, Canada.
Susie
S
Lau
Division of Gynecologic Oncology, University of Toronto, Canada.
Lilian T
LT
Gien
Division of Anatomic Pathology, University of British Columbia, Canada.
Blake
B
Gilks
Department of Pathology and Laboratory Medicine, University of Toronto, Canada.
Blaise
B
Clarke
Division of Gynecologic Oncology, University of Manitoba, Canada.
Anna
A
Cameron
Division of Gynecologic Oncology, University of Calgary, Canada.
Gregg
G
Nelson
Department of Pathology and Laboratory Medicine, University of Toronto, Canada.
Guangming
G
Han
Division of Gynecologic Oncology, CHUM-Hôpital Notre-Dame, Canada.
Vanessa
V
Samouëlian
Division of Gynecologic Oncology, University of Toronto, Canada.
T C
TC
Ho
Division of Obstetrics and Gynecology, University of British Columbia, Canada.
Kim
K
Louie
Division of Gynecologic Oncology, University of Toronto, Canada. Electronic address: Marcus.Bernardini@uhn.ca.
Marcus Q
MQ
Bernardini
D018262:Adenocarcinoma, Clear Cell / Q000401:mortality / Q000473:pathology*; D000368:Aged; D002170:Canada; D018269:Carcinoma, Endometrioid / Q000401:mortality / Q000473:pathology*; D002296:Carcinosarcoma / Q000401:mortality / Q000473:pathology*; D015331:Cohort Studies; D018572:Disease-Free Survival; D016889:Endometrial Neoplasms / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D018297:Neoplasms, Cystic, Mucinous, and Serous / Q000401:mortality / Q000473:pathology*; D011379:Prognosis; D012189:Retrospective Studies
Carcinosarcoma; Clear cell carcinoma; Endometrial carcinoma; High risk histotype; Serous carcinoma