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WB W. A. A. Borstlap
PT P. J. Tanis
TK T. W. A. Koedam
CM C. A. M. Marijnen
CC C. Cunningham
ED E. Dekker
ML M. E. van Leerdam
GM G. Meijer
NG N. van Grieken
IN I. D. Nagtegaal
CP C. J. A. Punt
MD M. G. W. Dijkgraaf
JW J. H. De Wilt
GB G. Beets
EG E. J. de Graaf
AG A. A. W van Geloven
MG M. F. Gerhards
HW H. L. van Westreenen
AV A. W. H. van de Ven
PD P. van Duijvendijk
IH I. H. J. T. de Hingh
JL J. W. A. Leijtens
CS C. Sietses
ES E. J. Spillenaar-Bilgen
RV R. J. C. L. M. Vuylsteke
CH C. Hoff
JB J. W. A. Burger
WG W. M. U. van Grevenstein
AP A. Pronk
RB R. J. I. Bosker
HP H. Prins
AS A. B. Smits
SB S. Bruin
DZ D. D. Zimmerman
LS L. P. S. Stassen
MD M. S. Dunker
MW M. Westerterp
PC P. P. Coene
JS J. Stoot
WB W. A. Bemelman
JT J. B. Tuynman
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The trial is designed as a non-inferiority trial. The expected percentage of patients who are free of local recurrence after a three-year follow-up is 98 % in the control group and 96 % in the study group. The difference in percentage of recurrence free patients between standard treatment and experimental treatment may not be larger than 7 %. Hence, the experimental treatment is non-inferior if at least 91 % of patients is free of local recurrence. This 91 % is seen as a worst case scenario when adjuvant treatment has no influence on local recurrence. Hypothesizing that the difference in percentage of patients with local recurrence may not be larger than 7 %, with a one sided alfa, an 80 % power and a drop-out of 5 % a sample size of 302 patients (151 per group) is needed.

Copyright and License information: The Author(s). ©2016
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