Is Sentinel Lymph Node Dissection Necessary in All Patients with Ductal Carcinoma in Situ Undergoing Total Mastectomy?

Abstract

When ductal carcinoma in situ (DCIS) is found on core needle biopsy, rates of upgrade to invasive cancer of 25 per cent and nodal positivity of 10 per cent have been reported. Sentinel lymph node dissection (SLND) is recommended when mastectomy is performed for DCIS. We investigated the role of SLND in DCIS patients undergoing partial and total mastectomy (TM). During the study period 2004 to 2013, 170 patients with DCIS were identified with a median age of 60 years (range 26–84 years). Of these, 58.2 per cent had partial mastectomy (PM) alone, 10.6 per cent had PM with SLND, and 31.1 per cent had TM with or without contralateral prophylactic mastectomy with SLND. Overall, SLND identified positive nodes in 4.2 per cent of patients. Upgrade to invasive carcinoma on final breast pathology was found in 8.2 per cent of patients overall, including 4.0 per cent of patients undergoing PM alone, 22.2 per cent undergoing PM with SLND, and 11.3 per cent for TM with SLND ( P = 0.8). In this study, patients diagnosed with DCIS on core needle biopsy had lower than expected rates of positive sentinel nodes and upgrade to invasive carcinoma. Surgeons and patients should revisit the necessity of SLND in DCIS patients undergoing mastectomy, which could lead to decreased health expenditure, resources, time, morbidity, and emotional impact on patients.

Sentinel lymph node positivity in patients undergoing mastectomies for ductal carcinoma in situ (DCIS)

“…We found the upstage rate to invasive carcinoma to be 29%. This is consistent with the reported 8%‐40% upstage rate and corresponds with Brennan et al's meta‐analysis which found 26% (95% CI: 23%‐30%) of patients with an initial diagnosis of DCIS on PCB had invasive disease on final pathology. In our study, the rate of SLN positivity among these upstaged patients was small but clinically significant (10%).…”

“…These factors were palpability, extent of disease on imaging larger than 1.20 cm and mass on pre‐op imaging. Other studies have demonstrated the utility of these preoperative markers of upstage risk . Multicentricity, patient reported symptoms and the presence of necrosis have also been reported as predictive factors; our study did not corroborate the significance of these additional findings.…”

“…The main strength of our study is the focus on patients undergoing mastectomies for a diagnosis of DCIS. While other studies have explored rate of upstaging and SLN positivity among women receiving either BCS and/or mastectomy for DCIS on PCB, our analysis demonstrates risk factors among this unique group on whom sentinel lymph node mapping cannot be reliably performed after surgery. Additionally, our study explores other clinical variables often omitted in the literature, such as strong family history of breast cancer and method of presentation.…”

“…However, there is a risk of underestimating invasion on PCB due to sampling error. DCIS diagnosed on PCB is upstaged to invasive disease on final surgical pathology at a rate of 8%‐40% . When DCIS is upstaged to invasive disease, the rate of SLN positivity is reported in the literature as 4%‐15% …”

De-escalating axillary surgery in early-stage breast cancer

“…Since 2005, the American Society of Clinical Oncology (ASCO) clinical practice guideline for SLNB in patients with early-stage breast cancer has recommended SLNB be performed during mastectomy but discouraged its use during lumpectomy [ 37 ]. The rationale for omitting sentinel lymph node (SLN) staging during lumpectomy includes the low rate of documented axillary metastases, even if upstaged on final pathology (ranging from 4 to 15%) [ [38] , [39] , [40] , [41] , [42] ], and the ability to return to the operative room should upstaging occur.…”