Is surgical axillary staging necessary in women with T1 breast cancer who are treated with breast-conserving therapy?

Survival After Sentinel Lymph Node Biopsy Compared with Axillary Lymph Node Dissection for Female Patients with T3-4c Breast Cancer

BACKGROUND

For patients with cN0 and T1-2 breast cancer, sentinel lymph node biopsy (SLNB) can provide survival results equivalent to axillary lymph node dissection (ALND). However, whether it can be performed on T3-4c patients is still controversial.

MATERIALS AND METHODS

Female patients diagnosed with cN0, T3-4c, and M0 breast cancer from 2004 to 2019 were identified using the surveillance, epidemiology and end results (SEER) database and divided into 2 groups, the SLNB group (1-5 regional lymph nodes examined) and the ALND group (≥10 regional lymph nodes examined). Finally, only those with pN0 disease were included in the SLNB group. The baseline differences in clinicopathological characteristics between groups were eliminated by propensity score matching (PSM). We also conducted subgroup analyses according to age, overall TNM stage, breast cancer subtypes, surgical approaches, radiation therapy, and chemotherapy. The primary endpoint was survival.

RESULTS

With a mean follow-up of 75 months, a total of 186 deaths were reported among 864 patients. The overall survival (OS) and breast cancer-specific survival (BCSS) in the SLNB group were 78.2% and 87.5%, respectively, and that in the ALND group were 78.7% and 87.3%, respectively. The unadjusted hazard ratio (HR) for OS and BCSS in the SLNB group (vs. the ALND group) was 0.922 (95% CI, 0.691-1.230, P = .580) and 0.874 (95% CI, 0.600-1.273, P = .481), respectively. Besides, the OS and BCSS between the 2 groups were also similar in all subgroup analyses.

CONCLUSIONS

SLNB may be performed on female patients with cN0, T3-4c, and M0 breast cancer.

Long-term outcome and axillary recurrence in elderly women (≥70 years) with breast cancer: 10-years follow-up from a matched cohort study

BACKGROUND AND OBJECTIVES

The oncological benefit of axillary surgery (AS), with sentinel lymph node biopsy (SLNB) or axillary dissection (ALND), in elderly women affected by breast cancer (BC) is controversial. We evaluated AS trends over a 10-year follow-up period as well as locoregional and survival outcomes in this subset of patients.

METHODS

Patients aged 70 years or older, treated between 1994 and 2008, were selected and divided in two groups, depending on whether or not AS was performed. A (1:1) matched analysis for all relevant clinicopathological features was performed. Outcomes were analyzed using the Kaplan-Meier method and univariate Cox-proportional hazard ratio analysis.

RESULTS

A total of 1.748 patients were identified and stratified by age (70-74, 75-79, 80-84). A matched analysis was performed for 252 patients: 122 who underwent AS and 122 who did not. At 10-year follow-up, ipsilateral breast tumor recurrence, distant metastasis and contralateral BC were similar, p = 0.83, p = 0.42 and p = 0.28, respectively. In the no-AS group, a significant increased risk of axillary lymph-node recurrence was identified at 5- and confirmed at 10-years (p = 0.038), without impact on overall survival at 5- and 10-years (p = 0.52). In the non-AS group, higher rate of axillary recurrence at 10-years was observed in patients with poorly differentiated (24.1%, 95% CI 7.2-46.2), highly proliferative (Ki67 ≥ 20%: 17.1%, 95% CI 0.6-33.3) and luminal B tumors (16.8%, 95% CI 5.9-35.5).

CONCLUSIONS

Axillary staging in elderly women does not impact long-term survival. Tailoring surgery according to tumor biology and age may improve locoregional outcome.

Mucinous carcinoma with micropapillary features is morphologically, clinically and genetically distinct from pure mucinous carcinoma of breast

Micropapillary features are seen in pure mucinous carcinoma of breast (PMC), which is termed mucinous carcinoma with micropapillary features (MPMC). However, whether MPMC can be identified as a morphologically, clinically or genetically distinct entity from PMC remains controversial. In this study, a retrospective review of 161 cases of breast mucinous carcinoma was conducted to assess the clinicopathologic features, prognostic implications, and genomic alterations of MPMC and PMC. MPMCs were identified in 32% of mucinous carcinomas showing an excellent interobserver agreement (ICC = 0.922). MPMCs occurred at a younger age and exhibited higher nuclear grade, more frequent lymph nodal metastasis, lymphovascular invasion, and HER2 amplification compared with PMCs. Survival analyses revealed that MPMCs show decreased progression-free survival compared with PMCs in both unmatched and matched cohorts. A similar outcome of distant disease-free survival was observed only in the unmatched cohort. However, no statistical difference in recurrence score was observed between MPMC and PMC using a 21-gene assay. Notably, both MPMCs and PMCs displayed low mutation burden, common mutations affecting TTN, GATA3, SF3B1, TP53, recurrent 6q14.1-q27 losses, and 8p11.21-q24.3 gains. GATA3, TP53, and SF3B1 were recurrently mutated in MPMCs, while PIK3CA mutations were exclusively detected in PMCs. Moreover, MPMCs harbored 17q and 20q gains as well as 17p losses, while PMCs displayed gains at 6p. PI3K-Akt, mTOR, ErbB, and focal adhesion pathways were more frequently deregulated in MPMCs than in PMCs, which may responsible for the aggressive tumor behavior of MPMCs. Our findings suggest that MPMC is morphologically, clinically, and genetically distinct from PMC.

Predicting Survival Benefit of Sparing Sentinel Lymph Node Biopsy in Low-Risk Elderly Patients With Early Breast Cancer: A Population-Based Analysis

Objective: The application of sentinel lymph node biopsy (SLNB) in elderly patients with early breast cancer remains somewhat controversial. This study aimed to establish individualized nomograms to predict survival outcomes of elderly patients with and without SLNB and find out which patients could avoid SLNB.

Methods: A total of 39,962 ≥70-year-old patients diagnosed with T1–T2 breast cancer in 2010–2015 were included from the Surveillance, Epidemiology, and End Results (SEER) program and were divided into the training set (n = 29,971) and the validation set (n = 9,991). Axillary surgery was not specified in the SEER database, and we defined removing one to five lymph nodes as SLNB. Survival analysis was performed using the Kaplan–Meier plot and log-rank test. Multivariate Cox analysis was utilized to identify risk factors for overall survival (OS) and breast-cancer-specific survival (BCSS). Nomograms and a risk stratification model were constructed.

Results: In the training set, patients with SLNB had better OS (adjusted HR 0.57, P < 0.001) and BCSS (adjusted HR 0.55, P < 0.001) than patients without SLNB. Multivariate COX analysis identified age, marital status, grade, subtype, T stage, and radiation as independent risk factors for OS and BCSS in both SLNB and non-SLNB groups (all P < 0.05). They were subsequently incorporated to establish nomograms to predict 3- and 5-year OS and BCSS for patients with or without SLNB. The concordance index ranged from 0.687 to 0.820, and calibration curves in the internal set and external set all demonstrated sufficient accuracies and good predictive capabilities. Further, we generated a risk stratification model which indicated that SLNB improved OS and BCSS in high-risk group (OS: HR 0.49, P < 0.001; BCSS: HR 0.54, P < 0.001), but not in the low-risk group (all P > 0.05).

Conclusion: Well-validated nomograms and a risk stratification model were constructed to evaluate survival benefit from SLNB in elderly patients with early-stage breast cancer. SLNB was important for patients in the high-risk group but could be omitted in the low-risk group without sacrificing survival. This study could assist clinicians and elderly patients to weigh the risk–benefit of SLNB and make individualized decisions. We look forward to more powerful evidence from prospective trials.

Challenge for Diagnostic Assessment of Deep Learning Algorithm for Metastases Classification in Sentinel Lymph Nodes on Frozen Tissue Section Digital Slides in Women with Breast Cancer

Purpose

Assessing the status of metastasis in sentinel lymph nodes (SLNs) by pathologists is an essential task for the accurate staging of breast cancer. However, histopathological evaluation of SLNs by a pathologist is not easy and is a tedious and time-consuming task. The purpose of this study is to review a challenge competition (HeLP 2018) to develop automated solutions for the classification of metastases in hematoxylin and eosin–stained frozen tissue sections of SLNs in breast cancer patients.

Materials and Methods

A total of 297 digital slides were obtained from frozen SLN sections, which include post–neoadjuvant cases (n = 144, 48.5%) in Asan Medical Center, South Korea. The slides were divided into training, development, and validation sets. All of the imaging datasets have been manually segmented by expert pathologists. A total of 10 participants were allowed to use the Kakao challenge platform for 6 weeks with two P40 GPUs. The algorithms were assessed in terms of the area under receiver operating characteristic curve (AUC).

Results

The top three teams showed 0.986, 0.985, and 0.945 AUCs for the development set and 0.805, 0.776, and 0.765 AUCs for the validation set. Micrometastatic tumors, neoadjuvant systemic therapy, invasive lobular carcinoma, and histologic grade 3 were associated with lower diagnostic accuracy.

Conclusion

In a challenge competition, accurate deep learning algorithms have been developed, which can be helpful in making frozen diagnosis of intraoperative SLN biopsy. Whether this approach has clinical utility will require evaluation in a clinical setting.