Long-term outcomes of magnetic resonance imaging-invisible endometrial cancer.
OBJECTIVE
Magnetic resonance imaging (MRI) is useful for staging endometrial cancer. The treatment and prognosis of MRI-invisible endometrial cancer remain unclear. The purpose of this study was to retrospectively evaluate the long-term outcomes of patients with MRI-invisible endometrial cancer.


METHODS
Between February 1995 and December 2011, we reviewed the medical records of 433 patients with endometrial cancer, which was staged IA on MRI. Of these patients, 89 had MRI-invisible cancer and 344 had MRI-visible cancer. Both cancers were treated with simple hysterectomy with or without lymph node dissection according to the surgeon's decision. Both cancers were compared regarding pathologic findings, recurrence rates, and survival rates.


RESULTS
The median sizes of MRI-invisible and MRI-visible cancers were 4 mm (0 to 40 mm) and 20 mm (0 to 89 mm), respectively (p<0.001). Myometrial invasion of these groups were detected in 20.2% (18/89) and 56.7% (195/344), respectively (p<0.001). Lymphadenectomy and follow-up imaging revealed no lymph node metastasis in patients with MRI-invisible cancers, while those revealed in 4.7% (16/344) of patients with MRI-visible cancers (p=0.052). The recurrence rates of MRI-invisible and MRI-visible cancers were 1.1% (1/89) and 7.8% (27/344), respectively (p=0.026). The recurrence-free survival rates of these groups were 98.9% (88/89) and 91.6% (315/344), respectively (p=0.022).


CONCLUSIONS
MRI-invisible endometrial cancer can be treated with less invasive surgery because of its lower tumor burden and better prognosis. This cancer may not require lymphadenectomy because of no metastasis or recurrence in lymph nodes.
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Hyun Jin
HJ
Choi
Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Sunyoung
S
Lee
Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. rapark@skku.edu.
Byung Kwan
BK
Park
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Tae Joong
TJ
Kim
Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Chan Kyo
CK
Kim
Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jung Jae
JJ
Park
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Chel Hun
CH
Choi
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Yoo Young
YY
Lee
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jeong Won
JW
Lee
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Duk Soo
DS
Bae
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Byoung Gie
BG
Kim
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016889:Endometrial Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D012189:Retrospective Studies
Endometrial Neoplasms; Lymph Nodes; Magnetic Resonance Imaging; Outcome; Stage