Resection of liver metastases from colorectal mucinous adenocarcinoma: is this a different disease? Results of a case-control study.
OBJECTIVE
To compare outcomes following liver resection of colorectal metastases (CRLM) from mucinous adenocarcinoma (Muc-CRLM) versus nonmucinous adenocarcinoma (non-Muc-CRLM).


BACKGROUND
Among colorectal adenocarcinomas, 10%-15% are mucinous and have worse prognoses than nonmucinous ones. Outcomes of liver resection for Muc-CRLM remain unknown.


METHODS
Among 701 patients undergoing liver resection for CRLM between 1998 and 2012, 102 (14.6%) had Muc-CRLM. Each was matched with a non-Muc-CRLM patient, based on tumor N status, disease-free interval (DFI) between primary tumor and metastases, CRLM number and diameter, extrahepatic disease, and preoperative chemotherapy.


RESULTS
Within the 2 groups, 69.6% of patients had N+ primary tumor, 72.5% had DFI of less than 12 months, 28.4% had 4 or more CRLM, and 22.5% had associated extrahepatic disease. 59.8% of patients received preoperative chemotherapy. Muc-CRLM patients had higher prevalences of right/transverse colon cancer (55.9% vs 29.4%; P<0.0001) and K-ras mutation (67 patients tested, 61.8% vs 36.4%; P=0.037), as well as lower response to preoperative chemotherapy (63.9% vs 85.2%; P=0.006). Multivariate analysis showed Muc-CRLM to have lower rates of 5-year overall (33.2% vs 55.2%; P=0.010) and disease-free survival (32.5% vs 49.3%; P=0.037). Muc-CRLM recurrence was more often peritoneal (20.3% vs 6.5%; P=0.024) and at multiple sites (47.5% vs 21.0%; P=0.002), and had lower rates of re-resection (16.9% vs 43.5%; P=0.002) and 3-year post-recurrence survival (11.7% vs 43.4%; P=0.0003).


CONCLUSIONS
Muc-CRLM patients strongly differed from non-Muc-CRLM patients, showing a lower chemotherapy response and higher K-ras mutation prevalence. Muc-CRLM appears to be a separate disease, which is associated with worse survival and aggressive rarely re-resectable recurrences.
*Department of HBP and Digestive Surgery †Department of Pathology ‡Department of Oncology, Ospedale Mauriziano, Torino, Italy §Department of Hepatobiliary Surgery, Humanitas Research Hospital, Rozzano (MI), Italy.
Luca
L
Viganò
Nadia
N
Russolillo
Alessandro
A
Ferrero
Giovanni
G
De Rosa
Erika
E
Ferreri
Fabio
F
Forchino
Elisa
E
Sperti
Lorenzo
L
Capussotti
D002288:Adenocarcinoma, Mucinous / Q000556:secondary* / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D017024:Chemotherapy, Adjuvant; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006498:Hepatectomy; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate