Adjuvant chemotherapy with or without pelvic radiotherapy after simultaneous surgical resection of rectal cancer with liver metastases: analysis of prognosis and patterns of recurrence.
OBJECTIVE
To investigate the outcomes of adjuvant chemotherapy (CT) or chemoradiotherapy (CRT) after simultaneous surgical resection in rectal cancer patients with liver metastases (LM).


METHODS
One hundred and eight patients receiving total mesorectal excision for rectal cancer and surgical resection for LM were reviewed. Forty-eight patients received adjuvant CRT, and 60 were administered CT alone. Recurrence patterns and prognosis were analyzed. Disease-free survival (DFS) and overall survival (OS) rates were compared between the CRT and CT groups. The inverse probability of the treatment-weighted (IPTW) method based on the propensity score was used to adjust for selection bias between the two groups.


RESULTS
At a median follow-up period of 47.7 months, 77 (71.3%) patients had developed recurrences. The majority of recurrences (68.8%) occurred in distant organs. By contrast, the local recurrence rate was only 4.7%. Median DFS and OS were not significantly different between the CRT and CT groups. After applying the IPTW method, we observed no significant differences in terms of DFS (hazard ratio [HR], 1.347; 95% confidence interval [CI], 0.759-2.392; p = 0.309) and OS (HR, 1.413; CI, 0.752-2.653; p = 0.282). Multivariate analyses showed that unilobar distribution of LM and normal preoperative carcinoembryonic antigen level (<6 mg/mL) were significantly associated with longer DFS and OS.


CONCLUSIONS
The local recurrence rate after simultaneous resection of rectal cancer with LM was relatively low. DFS and OS rates were not different between the adjuvant CRT and CT groups. Adjuvant CRT may have a limited role in this setting. Further prospective randomized studies are required to evaluate optimal adjuvant treatment in these patients.
Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Ho Jung
HJ
An
Chang Sik
CS
Yu
Sung-Cheol
SC
Yun
Byung Woog
BW
Kang
Yong Sang
YS
Hong
Jae-Lyun
JL
Lee
Min-Hee
MH
Ryu
Heung Moon
HM
Chang
Jin Hong
JH
Park
Jong Hoon
JH
Kim
Yoon-Koo
YK
Kang
Jin Cheon
JC
Kim
Tae Won
TW
Kim
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D000069287:Capecitabine; D059248:Chemoradiotherapy / Q000379:methods / Q000401:mortality / Q000706:statistics & numerical data; D017024:Chemotherapy, Adjuvant / Q000379:methods / Q000401:mortality / Q000706:statistics & numerical data; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D018572:Disease-Free Survival; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000031:analogs & derivatives; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008113:Liver Neoplasms / Q000401:mortality / Q000556:secondary* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology / Q000401:mortality; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D010388:Pelvis; D011182:Postoperative Care; D011336:Probability; D011379:Prognosis; D012004:Rectal Neoplasms / Q000401:mortality / Q000628:therapy*; D012189:Retrospective Studies; D015983:Selection Bias
D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D003841:Deoxycytidine; D000069287:Capecitabine; D002955:Leucovorin; D005472:Fluorouracil