ComManDS

Overview

Current NICE guidelines recommend sentinel node biopsy (SNB) for all patients undergoing mastectomy for Ductal Carcinoma in situ (DCIS). This retrospective audit is investigating the role of SNB in patients requiring completion mastectomy following involved margins during wide excision (breast conservation surgery) for DCIS. 

Objectives

Following wide excision for pure DCIS, the incidence of finding an invasive cancer during completion mastectomy is likely to be very low. In the rare event of finding an invasive cancer during completion mastectomy, the involvement of the sentinel node will also be low. Our hypothesis is that a routine SNB can be avoided in these patients. 

The objectives of the audit are:

1. To determine the incidence of invasive carcinoma on completion mastectomy following breast conserving surgery for pure DCIS
2. The incidence of sentinel node metastases during completion mastectomy 
3. The rate of SNB performed during completion mastectomy
4. Risk factors associated with invasive cancer in the completion mastectomy 
5. Generate data to improve current guidelines on the management of axilla for this subset of patients with DCIS

Inclusion/ exclusion criteria

Inclusion criteria

1. Wide local excision for pure DCIS
2. Completion mastectomy following wide local excision for pure DCIS between Jan 2010 to Dec 2021
3. Female >16 years of age

Exclusion criteria

1. Invasive carcinoma in WLE specimen
2. Male patients
3. Previous ipsilateral breast cancer
4. Metastatic breast cancer

Planned sample size

800 patients (20 to 70 patients per site – depending on the size of the unit).

Timeline

Data collection is planned to be completed by April 2026.