Disappearing or residual tiny (≤5 mm) colorectal liver metastases after chemotherapy on gadoxetic acid-enhanced liver MRI and diffusion-weighted imaging: Is local treatment required?
OBJECTIVE
To evaluate the clinical course of disappearing colorectal liver metastases (DLM) or residual tiny (≤5 mm) colorectal liver metastases (RTCLM) on gadoxetic acid-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in patients who had colorectal liver metastases (CLM) and received chemotherapy.


METHODS
Among 137 patients who received chemotherapy for CLM and underwent gadoxetic acid-enhanced MRI and DWI between 2010 and 2012, 43 patients with 168 DLMs and 48 RTCLMs were included. The cumulative in situ recurrence rate of DLM and progression rate of RTCLM and their predictive factors were evaluated.


RESULTS
A total of 150 DLMs and 26 RTCLMs were followed up without additional treatment. At 1 and 2 years, respectively, the cumulative in situ recurrence rates for DLM were 10.9 % and 15.7 % and the cumulative progression rates for RTCLM were 27.2 % and 33.2 %. The in situ recurrence rate at 2 years was 4.9 % for the DLM group that did not show reticular hypointensity of liver parenchyma on hepatobiliary phase.


CONCLUSIONS
DLM on gadoxetic acid-enhanced liver MRI and DWI indicates a high possibility of clinical complete response, especially in patients without chemotherapy-induced sinusoidal obstruction syndrome. Thirty-three percent of RTCLMs showed progression at 2 years.


CONCLUSIONS
• DLMs on gadoxetic acid-enhanced MRI and DWI showed low recurrence rates. • If there is sinusoidal obstruction syndrome, evaluation of DLM needs special care. • The progression rate for residual tiny CLMs was 33.2 % at 2 years.
Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-Gu, Seoul, 06351, Republic of Korea.|Department of Radiology, Soonchunhyang University College of Medicine, Cheonan Hospital, Cheonan-si, Chungcheongnam-do, Republic of Korea.
Seung Soo
SS
Kim
Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-Gu, Seoul, 06351, Republic of Korea. kd3893.song@samsung.com.
Kyoung Doo
KD
Song
Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-Gu, Seoul, 06351, Republic of Korea.
Young Kon
YK
Kim
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Hee Cheol
HC
Kim
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Jung Wook
JW
Huh
Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Young Suk
YS
Park
Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Joon Oh
JO
Park
Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Seung Tae
ST
Kim
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000556:secondary*; D003287:Contrast Media / Q000494:pharmacology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D019786:Gadolinium DTPA / Q000494:pharmacology*; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging / Q000379:methods*; D018365:Neoplasm, Residual; D015203:Reproducibility of Results
D000970:Antineoplastic Agents; D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA
Chemotherapy; Colorectal liver metastasis; Disappearing metastasis; Gadoxetic acid-enhanced MRI; Residual tiny metastasis