Management of Mammary Abscess with Vacuum Assisted Drainage (The "MAMMA-VAD" Trial)

Background: Breast abscess occurs in approximately 4-11% of women with mastitis [1]. Surgical incision drainage is reserved for large, deep seated and multiloculated abscess and/or those that fail image guided fine needle aspiration. Our work suggests the UK national average surgical intervention rate is 21% [range 0-100%] [2] accounting for ~2000 operations/year. Surgical intervention is typically painless but commonly requires a general anaesthetic, and can lead to scarring, distortion and disfigurement, with impact on quality of life. Vacuum assisted drainage (VAD) is a minimally invasive technique to drain the breast abscess in the outpatient setting, with case reports and case series of successful management in ~400 women to date. Compared to surgery, VAD has potential for improved patient satisfaction and at lower cost to the NHS. We do not know whether surgery or VAD results in faster resolution of symptoms and healing, or which has improved quality of life and lower cost. An RCT comparing outcomes between surgery and vacuum drainage in the treatment of large, mulitiloculated, resistant breast abscess is required and supported by patient and public involvement. Aims & Objectives: Our main aim is to establish the feasibility of a RCT and to investigate UK wide variation in outcomes following VAD that are vital to informing the design of a future trial. We aim to determine the number of eligible patients, confirm acceptability of randomisation and assess retention and attrition. We also aim to capture differences in quality of life outcomes and time to symptom resolution between VAD and surgery. Methods: A two-arm, multicentre, pan UK, randomised controlled trial involving 70 patients across ~26 NHS Centres. Patients with large (>5cm), deep seated or multiloculated abscesses, or abscesses that have failed an attempt at needle aspiration are eligible to be randomised to either surgery (standard care) or VAD (intervention). Clinical outcome measures include breast-related quality of life (BREAST-Q) and general quality of life (EQ-5D-5L) performed at baseline and 3 months following intervention, periprocedural pain (visual analogue scale) and time to resolution of symptoms. Treatment failure and need for repeated interventions will be recorded. Cessation of lactation or deviation from only feeding from the breast will be monitored. NHS costs including the cost of intervention, use of antibiotics and dressings, and hospital costs, including costs of treating complications will be recorded. Qualitative interviews with up to 30 patients and up to 30 clinicians will be used to assess acceptability, barriers and facilitators to implementation. Timeline: 31 months: 6 months set-up, 18 months for recruitment, 3 months to follow-up, 4 months to analyse and close-out. Impact / Dissemination: The feasibility study will inform a larger, multi-centre RCT and provide data to enable a health economic and carbon footprint analysis. The main RCT is likely to lead to a change in practice, meaning improved quality of life for patients with breast abscess at a lower cost to the NHS and environment.