The Effect of Sensory Nerve Coaptation in DIEP Flap Breast Reconstruction on the Quality of Life: A Double-Blind Randomized Controlled Trial

Breast cancer has become the most common cancer among women worldwide. Besides
women receiving treatment for breast cancer, women genetically at risk because
of BRCA1/2 mutations often undergo prophylactic mastectomy. Therefore, more
women have to live with the consequences of (prophylactic) breast cancer
treatment. In addition, the time after treatment continues to prolong since
women are younger when receiving therapy. Consequently, the quality of life
after (prophylactic) breast cancer treatment is becoming of fundamental
importance. Restoring the body to as normal as possible, after a mastectomy has
proven to increase quality of life. In terms of aesthetics, exceptional,
natural looking results can already be achieved by autologous breast
reconstruction. However, previous research shows that the question *does your
reconstructed breast feel like your own?*, is one of the most important
determinants in patient satisfaction. An innovative technique; sensory nerve
coaptation might restore the sensation of the reconstructed breast which could
significantly improve the quality of life of breast cancer patients according
to the first pilot study.

The primary objective of this randomized controlled trial is to evaluate the
effectiveness of sensory nerve coaptation in autologous breast reconstructions
on the sensibility of the reconstructed breast, compared to spontaneous sensory
recovery, and how this influences the quality of life of breast cancer
patients.

A double-blind single-center, randomized controlled trial (RCT), conducted in
Maastricht University Medical Center (Maastricht UMC+). Patients will be
randomised into one of two study groups: group 1 will receive a standard DIEP
flap breast reconstruction (without sensory nerve coaptation), group 2 will
receive a DIEP flap breast reconstruction with sensory nerve coaptation.

The sensory nerve coaptation will be an additional technique used in DIEP flap
breast reconstructions. In DIEP flap breast reconstruction the artery and vein
supplying the transplanted tissue are anastomosed to an artery and vein on the
thorax, mostly the internal mammary vessels. Technically, it is possible to
coapt a sensible nerve of the transplanted tissue to one of the thorax to
facilitate nerve regeneration of the reconstructed breast5. This will
approximately extend the operating time with 20 minutes and does not entail any
extra specific risks for the patient.

Participation is voluntarily. Participants can withdraw at any time during the
study without further consequences. Patients will be randomised into one of two
groups: they either will receive a sensory nerve coaptation during the DIEP
flap breast reconstruction, or they won*t. The last group, without a nerve
anastomosis, will therefore receive a normal DIEP flap breast reconstruction,
which is nowadays standard care for breast cancer patients. The operation time
is prolonged with approximately 20 minutes. Patients who undergo DIEP flap
breast reconstruction with sensory nerve coaptation are not more at risk
because of the prolonged operation time. The follow-up and aftercare will be
the same for both groups, protocolized for autologous breast reconstructions.
The BREAST-Q questionnaire will be completed before operation and at 6, 12 and
24 months post-operatively. Completing the BREAST-Q questionnaire will
approximately take 5 to 10 minutes each time. There are no risks or
complications associated.
The sensory measurements will be done before operation and at 3, 6, 12, 18 and
24 months post-operatively at special follow-up moments in the study. The
measurements will take place at the outpatient clinic and duration will be
approximately 45 minutes each time the participant is measured. The sensory
measurements will be done using SWM, PSSD and QST. These methods do not harm
the participant and are not painful . There are no risks or complications
associated or reported with these measurement techniques.
At the end of the individual follow-up period, at 24 months, all patients will
be asked by one of the researchers whether or not they would like to remain
blinded to the nerve coaptation and participate in a lengthened follow-up.
Patients who approve will have a longer study follow-up with two extra
measurement moments for breast sensation and quality of life: at 36
postoperative months (3 years) and at 60 postoperative months (5 years). The
researchers will also remain blinded.
Patients who would like to be unblinded will be asked whether they think they
have a nerve coaptation yes or no. Immediately afterwards they the result will
be handed out to the patient.