Role of Sentinel Lymph Node Biopsy in Microinvasive Breast Cancer

Feasibility of Omitting Sentinel Lymph Node Biopsy in an Under-screened Cohort of Breast Cancer Patients With a Premastectomy Diagnosis of Ductal Carcinoma In Situ

BACKGROUND

Nodal involvement in ductal carcinoma in situ (DCIS) is rare. In patients with DCIS diagnosis prior to mastectomy, a sentinel lymph node biopsy (SLNB) is usually performed during mastectomy, to avoid the risk of reoperation and the non-identification of SLN subsequently, should there be an upgrade to invasive cancer. We aimed to study the feasibility of omitting SLNB in an under-screened cohort, with mostly symptomatic patients and DCIS diagnosis before mastectomy, by determining the upgrade rate to invasive cancer/ DCIS microinvasion (DCISM) and its associated risk factors.

METHODS

Patients with pure DCIS diagnosis premastectomy were reviewed retrospectively. Patients with known DCISM or invasive cancer before mastectomy and bilateral cancers were excluded. Patients' demographics, radiological and pathological data premastectomy were analyzed.

RESULTS

A total of 189 patients were included. The mean age was 53.8 (range: 29-85) years old. About 64.4% presented with symptoms. 36.0% and 15.3% upgraded to invasive cancer and DCISM on mastectomy respectively. Palpable tumor (P = .0036), large size on ultrasound (P = .0283), tumor seen on mammogram and ultrasound (P = .0082), ultrasound-guided biopsy (P < .0001), high-grade DCIS on biopsy (P = .0350) and no open biopsy/lumpectomy before mastectomy (P < .0001) were associated with the upgrade, with the latter factor remaining significant after multivariable analysis. Nodal involvement was 8.47% and was associated with invasive cancer (P < .0001).

CONCLUSION

In a cohort who had DCIS diagnosis before mastectomy and were mostly symptomatic, the upgrade rate was 51.3%. Despite the high upgrade rate, nodal involvement remained comparable. Risk factors could select patients for omission of upfront SLNB, with a delayed SLNB planned if needed.

Superparamagnetic iron oxide (SPIO) for axillary mapping in patients with ductal carcinoma in situ undergoing mastectomy: single-institution experience

PURPOSE

Unnecessary axillary surgery can potentially be avoided in patients with DCIS undergoing mastectomy. Current guidelines recommend upfront sentinel lymph node biopsy during the index operation due to the potential of upstaging to invasive cancer. This study reviews a single institution's experience with de-escalating axillary surgery using superparamagnetic iron oxide dye for axillary mapping in patients undergoing mastectomy for DCIS.

METHODS

This is a retrospective single-institution cross-sectional study. All medical records of patients who underwent mastectomy for a diagnosis of DCIS from August 2021 to January 2023 were reviewed and patients who had SPIO injected at the time of the index mastectomy were included in the study. Descriptive statistics of demographics, clinical information, pathology results, and interval sentinel lymph node biopsy were performed.

RESULTS

A total of 41 participants underwent 45 mastectomies for DCIS. The median age of the participants was 58 years (IQR = 17; range 25 to 76 years), and the majority of participants were female (97.8%). The most common indication for mastectomy was diffuse extent of disease (31.7%). On final pathology, 75.6% (34/45) of mastectomy specimens had DCIS without any type of invasion and 15.6% (7/45) had invasive cancer. Of the 7 cases with upgrade to invasive disease, 2 (28.6%) of them underwent interval sentinel lymph node biopsy. All sentinel lymph nodes biopsied were negative for cancer.

CONCLUSION

The use of superparamagnetic iron oxide dye can prevent unnecessary axillary surgery in patients with DCIS undergoing mastectomy.

Prognostic Markers of Microinvasive Breast Carcinoma: A Systematic Review and Meta-Analysis

(1) Background: The prognostic factors of microinvasive (≤1 mm) breast carcinoma are not completely clear. The aim of this study was to perform a systematic review and meta-analysis to clarify these factors. (2) Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was followed. Two databases were interrogated, PubMed and Embase, and papers in English were included to address this question. The selected studies were those that reported on female patients affected by microinvasive carcinoma, and on prognostic factors with a hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS). (3) Results: In total, 618 records were identified. After removing duplicates (166), identification, and screening (336 by title and abstract alone, 116 by full text and eventual supplementary material), 5 papers were selected. Seven different meta-analyses were conducted in this study, all referring to DFS, analyzing the following prognostic factors: estrogen receptor, progesterone receptor, HER2 status, multifocality and grade of microinvasion, patient's age, and lymph node status. Only lymph node status was associated with prognosis and DFS (total number of cases: 1528; Z = 1.94; p = 0.05). The other factors examined did not significantly affect prognosis (p > 0.05). (4) Conclusions: Positive lymph node status significantly worsens prognosis in patients with microinvasive breast carcinoma.

Intraoperative diagnosis of «sentinel» lymph nodes in the patients with mammary gland cancer

Objective. To improve intraoperative determination of «sentinel» lymph nodes in patients, suffering mammary gland cancer. Materials and methods. In the 2016 – 2021 yrs period on the base of the Odessa Regional Clinical Hospital 200 patients, suffering mammary gland cancer Stages Т1–Т3N0М0, were operated, using two dyes: the blue patented dye and fluorescent dye indocyanine green. All the patients were distributed into two groups. In Group I in 100 patients the "sentinel" lymph nodes biopsy was conducted. The blue patented dye was used for the lymph nodes staining. The same was conducted in 100 patients of Group II with the "sentinel" lymph nodes biopsy. For the lymph nodes staining there were applied the blue patented dye and fluorescent dye indocyanine green, which were introduced intravenously into the upper extremity on the side of the affected mammary gland along outflow from the upper extremity to mammary gland. Results. General five–year survival after axillary lympho–dissection and after biopsy of «sentinel» lymph nodes have constituted 91 and 92%, accordingly, while recurrence–free five–year survival – 82.2 and 83.9% accordingly. Only in 1.1% patient a regional recurrence in «sentinel» lymph nodes on the affected mammary gland side was revealed. In 57% patients the unaffected «sentinel» lymph nodes were diagnosed, that's why further lympho–dissection was accomplished. In 43% women–patients there was revealed metastatic affection of the lymph nodes. Recurrence was registered in 0.2% patients as an isolated metastases in axillary lymph nodes. Conclusion. The method of the «sentinel» lymph nodes diagnosis in mammary gland cancer, using the dyes, permits to escape the performance of traumatic operations in favor of organ–preserving interventions with biopsy of «sentinel» lymph nodes.

Microinvasive breast cancer and the role of sentinel lymph node biopsy

Whether sentinel lymph node biopsy (SLNB) should be performed in patients with microinvasive breast cancer (MIBC) has been a matter of debate over the last decade. MIBC has a favorable prognosis and while metastasis to the axilla is rare, it can impact treatment recommendations. In this study we evaluated clinical and histological features in both MIBC and background DCIS including ER, PR, and HER-2, number of foci of MIBC, the extent of the DCIS, nuclear grade, presence of comedo necrosis, as well as surgical procedures, adjuvant treatment and follow up to identify variables which predict disease free survival (DFS), as well as the factors which influence clinical decision making. Our study included 72 MIBC patients with a mean patient follow-up time of 55 months. Three patients with MIBC had recurrence, and two deceased, leaving five patients in total with poor long-term outcomes and a DFS rate of 93.1%. Performing mastectomy, high nuclear grade, and negativity for ER and HER-2 were found to be associated with the use of SLNB, although none of these variables were found to be associated with DFS. One positive lymph node case was discovered following SLNB in our study. This suggests the use of SLNB may provide diagnostic information to some patients, although these are the anomalies. When comparing patients who had undergone SLNB to those which had not there was no difference in DFS. Certainly, the use of SLNB in MIBC is quite the conundrum. It is important to acknowledge that surgical complications have been reported, and traditional metrics used for risk assessment in invasive breast cancer may not hold true in the setting of microinvasion.

Regional Lymph Node Metastasis and Axillary Surgery of Microinvasive Breast Cancer: A Population-Based Study

Microinvasive breast cancer (MBC for short) is a rare entity with the decision of axillary surgery under debate in clinical practice. We aimed to unravel the lymph node metastasis (LNM) rate, axillary surgery, and prognosis of MBC based on 11,692 patients derived from the Surveillance Epidemiology and End Results (SEER) database between 2003 and 2015. In this retrospective study, 19.5% (2276/11,692) of patients received axillary lymph node dissection (ALND), 80.5% (9416/11,692) received non-ALND. In the total cohort, 10-year breast cancer-specific survival (BCSS) was 96.3%, and the LNM rate was 6.4% (754/11,692). Multivariate analyses showed that LNM had the strongest predictive weight (N3, HR 14.200, 95% CI 7.933−25.417; N2, HR 12.945, 95% CI 7.725−21.694; N1, HR 3.05, 95% CI 2.246−4.140, all p < 0.001). Kaplan−Meier analyses showed that ALND did not confer a survival benefit on 10-year BCS in patients with N0 (94.7% vs. 97.1%, p < 0.001) and in patients with 1−2 positive nodes (92.1% vs. 89.5%, p = 0.355), respectively, when compared to non-ALND. Our study demonstrated that the vast majority of MBC have a low LNM rate and excellent prognosis; patients with LNM showed poor prognosis. Assessment of lymph node status is necessary, and non-ALND surgery is required and sufficient for MBC with 0−2 positive nodes.

Low incidence of lymph node metastasis in patients with microinvasive breast cancer: a Korean nationwide study

Purpose

Microinvasive breast cancer (MIBC) is an invasive carcinoma with a tumor dimension not exceeding 1 mm. Owing to its low incidence, the rate of axillary node metastasis and its management are not well established. The aim of this study was to assess the incidence of lymph node metastasis (LNM) and identify variables associated with LNM, as well as to evaluate the need for axillary staging in MIBC patients by analyzing nationwide data.

Methods

The Korean Breast Cancer Society registry was searched to identify MIBC patients diagnosed between January 1996 and April 2020. Patients without neoadjuvant chemotherapy experiences, systemic metastasis, and missing or discordant data were eligible for the analysis. The incidence rate of LNM was determined, and variables associated with LNM were identified by multivariable regression analysis.

Results

Of 2,427 MIBC patients identified, 98 (4.0%) had LNM and 12 (0.5%) had N2/3 disease. Type of breast operation (odds ratio [OR], 2.093; 95% confidence interval [CI], 1.332–3.290; P = 0.001), age (OR, 2.091; 95% CI, 1.326–3.298; P = 0.002), hormone receptor status (OR, 2.220; 95% CI, 1.372–3.594; P = 0.001), and lymphovascular invasion (OR, 11.143; 95% CI, 6.354–19.540; P < 0.001) were significantly related to LNM.

Conclusion

The incidence of LNM in MIBC patients was only 4.0% in our study, suggesting that de-escalation of axillary surgical interventions could be carefully considered. The indications for axillary staging should be individualized considering tumor volume, age, hormone receptor status, and lymphovascular invasion to improve the quality of life of MIBC survivors.

Clinical characteristics of breast ductal carcinoma in situ with microinvasion: a narrative review

Ductal carcinoma in situ (DCIS) with microinvasion (DCIS-MI) is defined as the extension of cancer cells beyond the basement membrane into adjacent tissue with no focus larger than 1 mm or a maximum diameter of less than 1 mm for multiple invasive foci. DCIS-MI constitutes approximately 1% of all breast cancer cases and 5% to 10% of cases of DCIS. The current literature is controversial concerning the clinical prognostic features and management of DCIS-MI. This narrative review described recently reported literature regarding the characteristics, diagnosis, treatment, and prognosis of DCIS-MI.

Axillary surgery in breast cancer: An updated historical perspective

This historical surgical retrospection focuses on the temporal de-escalation axillary surgery, focusing on the unceasing efforts of researchers toward new challenges, as documented by extensive studies and trials. Axillary surgery has evolved, aiming to offer the best oncologic treatment and improve the quality of life of women. Axillary lymph-node dissection (ALND) has been replaced by sentinel lymph-node biopsy (SLNB) in women with early clinically node-negative breast cancer, providing adequate axillary nodal staging information with minimal morbidity, and becoming the standard of care in the management of breast cancer. However, this is only the beginning. Strategies in defining systemic and radiotherapeutic treatments have gradually been optimized, offering increasingly refined and targeted breast cancer treatment tools. In recent years, the paradigm of completion ALND after a positive SLNB has been questioned, and several studies have led to revolutionary changes in clinical practice. Moreover, the increasingly pivotal role played by neoadjuvant chemotherapy (NAC) has had a profound effect on the extent of axillary surgery, paving the way to a more finite "targeted" procedure in women with node-positive breast cancer who convert to negative nodes clinically after NAC. The utility of SLNB itself and its subsequent omission in women with negative nodes clinically and breast conservative surgery is also under scientific evaluation. The changes over time in the surgical approach to breast cancer have been numerous and significant. The novel emerging perspective characterized by recent advances in biology and genetics, in dedicated axillary ultrasound imaging and chemotherapy regimens, is the present reality that points to the future of axillary node treatment in breast cancer.