Impact of anticancer treatment on recurrent obstruction in covered metallic stents for malignant biliary obstruction.
BACKGROUND
In patients with unresectable malignant biliary obstruction (MBO), anticancer treatment is often administered. The impact of anticancer treatment on recurrent biliary obstruction in covered self-expandable metallic stents (SEMS) has not been fully elucidated.


METHODS
Data on 279 patients enrolled in a multicenter prospective cohort study of two different covered SEMS for distal MBO, WATCH study (141 partially covered WallFlex stents and 138 partially covered Wallstents) were retrospectively analyzed. The rates and causes of recurrent biliary obstruction (stent occlusion or migration) were compared between anticancer treatment group (n = 173) and best supportive care alone (BSC) group (n = 106). Cumulative time and prognostic factors for recurrent biliary obstruction were analyzed, using a proportional hazards model with death without recurrent biliary obstruction as a competing risk.


RESULTS
The overall rate (43 vs. 25%, P = 0.002) and the cumulative incidence (16.1 vs. 8.2, 27.9 vs. 18.9 and 44.1 vs. 26.6% at 3, 6 and 12 months, P = 0.030 by Gray's test) of recurrent biliary obstruction were significantly higher in anticancer treatment group compared with BSC group. The multivariate analysis revealed anticancer treatment [subdistribution hazard ratio (SHR) 1.93, P = 0.007) as well as the use of a partially covered WallFlex stent (SHR 0.65, P = 0.049) as prognostic factors.


CONCLUSIONS
Anticancer treatment was a risk factor for recurrent biliary obstruction in covered SEMS for distal MBO. The superiority of a partially covered WallFlex stent was again confirmed in this competing risk analysis; UMIN-CTR: UMIN000002293.
Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
Yousuke
Y
Nakai
Hiroyuki
H
Isayama
Tsuyoshi
T
Mukai
Takao
T
Itoi
Iruru
I
Maetani
Hiroshi
H
Kawakami
Ichiro
I
Yasuda
Hiroyuki
H
Maguchi
Shomei
S
Ryozawa
Keiji
K
Hanada
Osamu
O
Hasebe
Kei
K
Ito
Hiorofumi
H
Kawamoto
Hitoshi
H
Mochizuki
Yoshinori
Y
Igarashi
Atsushi
A
Irisawa
Tamito
T
Sasaki
Osamu
O
Togawa
Taro
T
Hara
Hideki
H
Kamada
Nobuo
N
Toda
Tsuyoshi
T
Hamada
Hirofumi
H
Kogure
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D002779:Cholestasis / Q000209:etiology* / Q000601:surgery; D004067:Digestive System Neoplasms / Q000150:complications* / Q000188:drug therapy; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008670:Metals; D008875:Middle Aged; D010166:Palliative Care / Q000379:methods; D011475:Prosthesis Failure; D012189:Retrospective Studies; D012307:Risk Factors; D055502:Secondary Prevention; D015607:Stents / Q000009:adverse effects
D000970:Antineoplastic Agents; D008670:Metals