The value of completion axillary treatment in sentinel node positive breast cancer patients undergoing a mastectomy: a Dutch randomized controlled multicentre trial (BOOG 2013-07).
BACKGROUND
Trials failed to demonstrate additional value of completion axillary lymph node dissection in case of limited sentinel lymph node metastases in breast cancer patients undergoing breast conserving therapy. It has been suggested that the low regional recurrence rates in these trials might partially be ascribed to accidental irradiation of part of the axilla by whole breast radiation therapy, which precludes extrapolation of results to mastectomy patients. The aim of the randomized controlled BOOG 2013-07 trial is therefore to investigate whether completion axillary treatment can be safely omitted in sentinel lymph node positive breast cancer patients treated with mastectomy.


METHODS
This study is designed as a non-inferiority randomized controlled multicentre trial. Women aged 18 years or older diagnosed with unilateral invasive clinically T1-2 N0 breast cancer who are treated with mastectomy, and who have a maximum of three axillary sentinel lymph nodes containing micro- and/or macrometastases, will be randomized for completion axillary treatment versus no completion axillary treatment. Completion axillary treatment can consist of completion axillary lymph node dissection or axillary radiation therapy. Primary endpoint is regional recurrence rate at 5 years. Based on a 5-year regional recurrence free survival rate of 98 % among controls and 96 % for study subjects, the sample size amounts 439 per arm (including 10 % lost to follow-up), to be able to reject the null hypothesis that the rate for study and control subjects is inferior by at least 5 % with a probability of 0.8. Results will be reported after 5 and 10 years of follow-up.


CONCLUSIONS
We hypothesize that completion axillary treatment can be safely omitted in sentinel node positive breast cancer patients undergoing mastectomy. If confirmed, this study will significantly decrease the number of breast cancer patients receiving extensive treatment of the axilla, thereby diminishing the risk of morbidity and improving quality of life, while maintaining excellent regional control and without affecting survival.


BACKGROUND
The BOOG 2013-07 study is registered in the register of ClinicalTrials.gov since April 10, 2014, Identifier: NCT02112682 .
Division of Surgical Oncology, Maastricht University Medical Centre, Maastricht, The Netherlands. lorivanroozendaal@gmail.com.|GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands. lorivanroozendaal@gmail.com.|Department of Surgical Oncology, Maastricht University Medical Centre, P.O. Box 5800 6202 AZ, Maastricht, The Netherlands. lorivanroozendaal@gmail.com.
L M
LM
van Roozendaal
Division of Surgical Oncology, Radboud university medical centre, Nijmegen, The Netherlands. Hans.deWilt@radboudumc.nl.
J H W
JH
de Wilt
Division of Surgical Oncology, Diakonessenhuis Hospital, Utrecht, The Netherlands. TvDalen@diakhuis.nl.
T
T
van Dalen
Division of Surgical Oncology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands. j.vd.hage@nki.nl.
J A
JA
van der Hage
Division of Surgical Oncology, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands. ljastrobbe@cwz.nl.
L J A
LJ
Strobbe
Department of Radiation Oncology, Maastricht University Medical Centre (MAASTRO clinic), Maastricht, The Netherlands. liesbeth.boersma@maastro.nl.|GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands. liesbeth.boersma@maastro.nl.
L J
LJ
Boersma
Division of Medical Oncology, Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands. s.linn@nki.nl.
S C
SC
Linn
Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands. marc.lobbes@mumc.nl.|GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands. marc.lobbes@mumc.nl.
M B I
MB
Lobbes
Department of Radiation Oncology, Radboud university medical centre, Nijmegen, The Netherlands. philip.poortmans@radboudumc.nl.
P M P
PM
Poortmans
Division of Medical Oncology, Maastricht University Medical Centre, Maastricht, The Netherlands. vcg.tjan.heijnen@mumc.nl.|GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands. vcg.tjan.heijnen@mumc.nl.
V C G
VC
Tjan-Heijnen
Department of Pathology, Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands. k.vd.vijver@nki.nl.
K K B T
KK
Van de Vijver
Department of Medical and Clinical Psychology, Tilburg University, Tilburg, The Netherlands. J.deVries@uvt.nl.
J
J
de Vries
Radiation Oncology, Arnhem Institute for Radiation Oncology, Arnhem, The Netherlands. H.Westenberg@arnhemrti.nl.
A H
AH
Westenberg
Department of Clinical Epidemiology and Medical Technology Assessment, Maastricht University Medical Centre, Maastricht, The Netherlands. fons.kessels@mumc.nl.
A G H
AG
Kessels
Division of Surgical Oncology, Maastricht University Medical Centre, Maastricht, The Netherlands. m.smidt@mumc.nl.|GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands. m.smidt@mumc.nl.
M L
ML
Smidt
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001365:Axilla; D001943:Breast Neoplasms / Q000532:radiotherapy / Q000601:surgery*; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008408:Mastectomy; D008875:Middle Aged; D009426:Netherlands; D021701:Sentinel Lymph Node Biopsy; D055815:Young Adult