Prevention of Postoperative Complications by Negative Pressure Therapy After Complex Breast Cancer Surgery

In 2022, excisional surgery is still one of the mainstays of breast cancer treatment. The excisional surgery is often combined with adjuvant treatments, which may include medical treatments such as chemotherapy, targeted therapies and immunotherapy, hormone therapy and radiotherapy. All these treatments have toxicities that impact on patients' quality of life.

One of the main complications of surgery is scarring. The rate is around 2% for "simple" breast surgery (conservative breast surgery - total mastectomy). This rate can rise sharply in the case of "complex" breast surgery, such as high-level oncoplasty, or mastectomy with Immediate Breast Reconstruction (IBR). This rate of surgical wound complications (ischemia, necrosis, dehiscence, infection) reached 20% in our local series of Immediate Breast Reconstruction (IBR) by prosthesis. This rate may exceed 30% in some series, depending on the surgical technique and the population, in cases of smoking, diabetes, previous radiotherapy, obesity and large breast volume. The increasing prevalence of these risk factors in the population means that scarring disorders must be taken into account in daily cancer care.

The impact of these scarring disorders is manifold:

• Delayed initiation of adjuvant therapy with an impact on overall survival.

• Cosmetic impact of scarring

• Possible loss of prosthetic breast reconstruction

• Patient dissatisfaction, with increased burden of care

• Overall impact on patient quality of life

• Economic impact linked to the length of care over time (consumption of dressing materials and personal time) Preventing the onset of wound-healing disorders is therefore vital in order to avoid these multiple consequences for the patient and the healthcare system.

In breast surgery, the use of preventive NPT (Negative Pressure Therapy) has been little studied. The NPT has been used mainly in cosmetic surgery procedures such as breast reduction, with results in favor of NPT. The most comprehensive study is a multicenter randomized trial which included 200 patients scheduled for bilateral breast reduction. In this trial, the comparison was made between the 2 breasts, each patient being her own control. The calculation of the number of subjects was based on a reduction in the complication rate from 20% to 10% (i.e., a 50% reduction). The study was positive, showing a reduction in the dehiscence rate at day 21 from 26% to 16%. In this study, patients were under-selected, and around 40% had risk factors for complications. A second randomized study, with similar methodology and judgment criteria, included 32 patients undergoing bilateral breast reduction. The results of this study are significant, but unfortunately there weren't much detail in the publication.

There is little scientific data concerning the use of negative pressure therapy after immediate breast reconstruction. There are very few data on the use of Negative pressure Therapy (NPT) after immediate Breast Reconstruction (IBR), a treatment-reconstruction strategy that has been expanding rapidly since recent years. The current literature reports only 3 studies on the use of preventive Negative pressure Therapy (NPT) in oncologic breast surgery. All three are retrospective, case-control studies with serious limitations. The largest published series involved 356 patients and 665 breasts. A reduction was reported in the overall complication rate from 15.9% to 8.5%, and a significant reduction in several criteria: infection, seroma, scar dehiscence and necrosis. However, the study presents significant biases, with non-comparable populations in terms of co-morbidities, surgical procedure performed, inclusion periods (and therefore experience in performing oncological surgery). There was also a high probability of under-assessment or postponement of post-operative complications, which is typical of published retrospective surgical studies.

The published results therefore strongly encourage further investigation of Negative Pressure Therapy (NPT) in oncological breast surgery.

Our hypothesis, then, is that preventive NPT in the immediate post-operative phase of complex breast surgery can prevent the onset of post-operative scarring disorders and shorten the time to complete healing.

To date, there are no randomized prospective studies of NPT in complex oncologic breast surgery. Randomized studies already published in general surgery provide a good level of evidence for the efficacy of NPT in preventing local post-operative complications. The latest systematic review and meta-analysis found a reduction in the risk of surgical site infection, from 13% to 8.8%, all types of surgery included. The benefit on the risk of dehiscence in general surgery is less strong, but a 30% reduction was found in a meta-analysis of studies involving only a preventive NPT device, a device widely used throughout the world.

In view of these results from randomized trials in general surgery and non-oncological breast surgery, and the results of retrospective studies in oncological breast surgery, a randomized trial must be carried out. This randomized controlled trial will be pragmatic, incorporating an intermediate analysis, given the endpoint evaluating the reduction in complications in a surgical context, to rapidly meet our objectives with a sufficient level of evidence to have an immediate impact on patients and modify practice.