Rates of margin positive resection with breast conservation for invasive breast cancer using the NCDB

Pushing the envelope in breast conserving surgery - is multiple-wire localization (3 or more wires) associated with increased risk of compromised margins and long-term recurrence?

INTRODUCTION

In the last two decades there has been a paradigm shift with breast conserving surgery (BCS) being applied to larger and more extensive breast malignancies. The aim of this study is to examine the success of BCS being performed in patients with extensive breast malignancies requiring at least 3 wires for localization, and to assess possible risk factors for failure.

MATERIALS AND METHODS

We performed a retrospective single center review of 232 patients who underwent BCS between 2010 and 2020 requiring at least 3 wires for localization, thus comprising the multi-wire group (MWG). The cohort included a control group of 232 single-wire BCS patients (SWG) chronologically matched with the MWG. Patients with either invasive malignancy or ductal carcinoma in situ (DCIS) were included in the study. Clinical, radiological, and pathological data was collected. Proportions of positive surgical margins, re-lumpectomies and conversion to mastectomy were calculated. Survival analysis for locoregional and distant recurrence was performed.

RESULTS

Women in the MWG were younger (mean age 57 vs. 63.1, P < 0.001), had larger tumor size (mean size 5.1 cm vs. 1.3 cm, p < 0.001), a higher prevalence of calcifications on mammograms (72 % vs. 17 %, P < 0.001), a higher proportion of positive lymph nodes (75 % vs. 45 %, P = 0.019), and an elevated incidence of a ductal carcinoma in situ (DCIS) component (72 % vs. 38 %, P < 0.001). Positive surgical margins were higher in the MWG (13 % vs 7 %, P = 0.03), which lead to higher proportions of re-lumpectomies or conversion to mastectomies (7 % vs 4 %, P = 0.17). On multivariate analysis of the entire cohort, patients with positive margins were more likely to have a DCIS component (77 % vs 53 %, P = 0.001), an infiltrating lobular carcinoma (ILC) component (15 % vs 9 %, P = 0.013), and positive ER hormonal status (94 % vs 85 %, p = 0.05). The number of wires was not an independent predictor of positive margins. On long-term analysis, the locoregional disease-free survival was similar between the SWG and MWG (P = 0.1). However, the MWG showed higher rates of distant metastasis (12 % vs 4 %, P = 0.006).

CONCLUSIONS

BCS requiring 3 or more wires is associated with a slightly higher proportion of positive margins. The increased risk of positive margins appears to be related to the type of tumor (DCIS component, ILC component and ER status) rather than to the number of wires. The number of wires does not significantly impact locoregional disease-free survival.

Deep learning-guided adjuvant chemotherapy selection for elderly patients with breast cancer

PURPOSE

The efficacy of adjuvant chemotherapy in elderly breast cancer patients is currently controversial. This study aims to provide personalized adjuvant chemotherapy recommendations using deep learning (DL).

METHODS

Six models with various causal inference approaches were trained to make individualized chemotherapy recommendations. Patients who received actual treatment recommended by DL models were compared with those who did not. Inverse probability treatment weighting (IPTW) was used to reduce bias. Linear regression, IPTW-adjusted risk difference (RD), and SurvSHAP(t) were used to interpret the best model.

RESULTS

A total of 5352 elderly breast cancer patients were included. The median (interquartile range) follow-up time was 52 (30-80) months. Among all models, the balanced individual treatment effect for survival data (BITES) performed best. Treatment according to following BITES recommendations was associated with survival benefit, with a multivariate hazard ratio (HR) of 0.78 (95% confidence interval (CI): 0.64-0.94), IPTW-adjusted HR of 0.74 (95% CI: 0.59-0.93), RD of 12.40% (95% CI: 8.01-16.90%), IPTW-adjusted RD of 11.50% (95% CI: 7.16-15.80%), difference in restricted mean survival time (dRMST) of 12.44 (95% CI: 8.28-16.60) months, IPTW-adjusted dRMST of 7.81 (95% CI: 2.93-11.93) months, and p value of the IPTW-adjusted Log-rank test of 0.033. By interpreting BITES, the debiased impact of patient characteristics on adjuvant chemotherapy was quantified, which mainly included breast cancer subtype, tumor size, number of positive lymph nodes, TNM stages, histological grades, and surgical type.

CONCLUSION

Our results emphasize the potential of DL models in guiding adjuvant chemotherapy decisions for elderly breast cancer patients.

Association of clinicopathologic and molecular factors with the occurrence of positive margins in breast cancer

PURPOSE

To explore the association of clinicopathologic and molecular factors with the occurrence of positive margins after first surgery in breast cancer.

METHODS

The clinical and RNA-Seq data for 951 (75 positive and 876 negative margins) primary breast cancer patients from The Cancer Genome Atlas (TCGA) were used. The role of each clinicopathologic factor for margin prediction and also their impact on survival were evaluated using logistic regression, Fisher's exact test, and Cox proportional hazards regression models. In addition, differential expression analysis on a matched dataset (71 positive and 71 negative margins) was performed using Deseq2 and LASSO regression.

RESULTS

Association studies showed that higher stage, larger tumor size (T), positive lymph nodes (N), and presence of distant metastasis (M) significantly contributed (p ≤ 0.05) to positive surgical margins. In case of surgery, lumpectomy was significantly associated with positive margin compared to mastectomy. Moreover, PAM50 Luminal A subtype had higher chance of positive margin resection compared to Basal-like subtype. Survival models demonstrated that positive margin status along with higher stage, higher TNM, and negative hormone receptor status was significant for disease progression. We also found that margin status might be a surrogate of tumor stage. In addition, 29 genes that could be potential positive margin predictors and 8 pathways were identified from molecular data analysis.

CONCLUSION

The occurrence of positive margins after surgery was associated with various clinical factors, similar to the findings reported in earlier studies. In addition, we found that the PAM50 intrinsic subtype Luminal A has more chance of obtaining positive margins compared to Basal type. As the first effort to pursue molecular understanding of the margin status, a gene panel of 29 genes including 17 protein-coding genes was also identified for potential prediction of the margin status which needs to be validated using a larger sample set.

Evaluation of the Influence of Geodimensional and Histological Parameters on the Need for Margin Widening in Breast Lesions Marked With Magnetic Seeds

Objective

Breast cancer is an important topic worldwide, posing morbidity and mortality to women. Considerable efforts have been put in the early recognition of malignancy through different screening methods, such as mammography and ultrasound. The precise localization of infraclinical malignant lesions is key in surgical management and magnetic seeds gather particular interest for this purpose. As with other systems, a need for reintervention may be needed to obtain adequate surgical margins. This work evaluated the relation between the need for surgical reintervention in order to obtain negative margins and geodimensional and histological parameters. The main objective was the identification of parameters significantly associated with reintervention for margin widening.

Materials and Methods

A retrospective analysis of 198 patients from a single centre was performed. The association between pre-defined geodimensional and histological parameters and the need for margin widening in infraclinical lesions marked with magnetic seed was evaluated.

Results

Results showed that reintervention to widen margins was significantly higher in patients with ductal carcinoma in situ (DCIS) in the pre-operative biopsy when compared with invasive carcinoma (p = 0.03) in the bivariate analysis. No statistically significant differences were observed between the need for reintervention and lesion size (p = 0.197), breast quadrant location (p = 0.626) and distance of skin to lesion (p = 0.356).

Conclusion

This work suggests that a more invasive margin clearance in lesions with a pre-operative DCIS diagnosis might obviate the need for reintervention to obtain negative margins. On the other hand, it is not necessary to be surgically more invasive in larger lesions, deeply located or that are present in a certain quadrant, since there are no significant differences regarding the need for reintervention.

The Impact of Preoperative Breast MRI on Timing of Surgical Management in Newly Diagnosed Breast Cancer

Purpose: Preoperative breast MRI has been recommended at our center since 2016 for invasive lobular carcinoma and cancers in dense breasts. This study examined how preoperative breast MRI impacted surgical timing and outcomes for patients with newly diagnosed breast cancer. Methods: Retrospective single-center study of consecutive women diagnosed with new breast cancer between June 1, 2019, and March 1, 2021, in whom preoperative breast MRI was recommended. MRI, tumor histology, breast density, post-MRI biopsy, positive predictive value of biopsy (PPV3), surgery, and margin status were recorded. Time from diagnosis to surgery was compared using t-tests. Results: There were 1054 patients reviewed, and 356 were included (mean age 60.9). Of these, 44.4% (158/356) underwent preoperative breast MRI, and 55.6% (198/356) did not. MRI referral was more likely for invasive lobular carcinoma, multifocal disease, and younger patients. Following preoperative MRI, 29.1% (46/158) patients required additional breast biopsies before surgery, for a PPV3 of 37% (17/46). The time between biopsy and surgery was 55.8 ± 21.4 days for patients with the MRI, compared to 42.8 ± 20.3 days for those without (P < .00001). MRI was not associated with the type of surgery (mastectomy vs breastconserving surgery) (P = .44) or rate of positive surgical margins (P = .52). Conclusion: Among patients who underwent preoperative breast MRI, we observed significant delays to surgery by almost 2 weeks. When preoperative MRI is requested, efforts should be made to mitigate associated delays.

The adoption of oncoplastic surgery: Is there a learning curve?

INTRODUCTION

Oncoplastic surgery (OPS) is a form of breast conservation surgery involving partial mastectomy followed by volume displacement or replacement surgery. As the field of OPS is growing, we sought to determine if there was a learning curve to this surgery.

METHODS

A retrospective chart review was conducted of all patients who underwent OPS over a 6-year period with a single surgeon formally trained in both Plastic Surgery and Breast Oncology. Cumulative summation analysis (CUSUM) was performed on mean operative time to generate the learning curve and learning curve phases. Outcomes were compared between phases to determine significance.

RESULTS

Mean operative time decreased significantly across the 6-year period, generating three distinct learning curve phases: Learner phase (cases 1-23), Competence phase (24-73), and Mastery phase (74 and greater). The overall positive margin rate was 10.9% and there was no significant difference in rates between phases (p = 0.49). Overall complication rates, reoperation rates, and locoregional recurrence remained the same across all phases (p = 0.16; p = 0.65; p = 0.41). The rate of partial nipple loss decreased between phases (p = 0.02).

CONCLUSION

As with many complex operations, there does appear to be a learning curve with OPS, as the operative time and the rates of partial nipple loss decreased over time.

Single Versus Dual Surgeon Approaches to Oncoplastic Surgery: A Comparison of Outcomes

INTRODUCTION

Oncoplastic surgery (OPS) is traditionally performed using a dual surgeon (DS) approach that involves both a breast surgeon and a plastic surgeon. It is also performed using a single surgeon (SS) approach with a surgeon trained in both breast surgical oncology and plastic surgery. We sought to determine if outcomes differed between SS versus DS OPS approaches.

METHODS

A retrospective chart review was conducted of all OPS performed in a single health system over a 6-y period by either an SS or a DS approach. Primary outcomes were rates of positive margins and the overall complication rate; secondary outcomes were loco-regional recurrence, disease-free survival, and overall survival.

RESULTS

A total of 217 patients were identified; 117 were SS cases and 100 were DS cases. Baseline preoperative patient characteristics were similar between the two groups as there was no difference in mean Charlson Comorbidity Index scores (P = 0.07). There was no difference in tumor stage (P = 0.09) or nodal status (P = 0.31). Rates of positive margins were not significantly different (10.9% (SS) versus 9% (DS); P = 0.81), nor were rates of complications (11.1% (SS) versus 15% (DS); P = 0.42). Rates of locoregional recurrence were also not significantly different (1.7% (SS) versus 0% (DS); P = 0.5). Disease-free survival and overall survival were not significantly different at 1-y, 3-y, and 5-y time points (P = 0.20 and P = 0.23, respectively) although follow-up time was not sufficient for definitive analysis regarding survival.

CONCLUSIONS

Both SS and DS approaches to OPS have similar outcomes with regards to positive margin rates and surgical complication rates and are comparably safe.

Does Breast Cancer Subtype Impact Margin Status in Patients Undergoing Partial Mastectomy?

Background

Molecular subtype in invasive breast cancer guides systemic therapy. It is unknown whether molecular subtype should also be considered to tailor surgical therapy. The present investigation was designed to evaluate whether breast cancer subtype impacted surgical margins in patients with invasive breast cancer stage I through III undergoing breast-conserving therapy.

Methods

Data from 2 randomized trials evaluating cavity shave margins (CSM) on margin status in patients undergoing partial mastectomy (PM) were used for this analysis. Patients were included if invasive carcinoma was present in the PM specimen and data for all 3 receptors (ER, PR, and HER2) were known. Patients were classified as luminal if they were ER and/or PR positive; HER2 enriched if they were ER and PR negative but HER2 positive; and TN if they were negative for all 3 receptors. The impact of subtype on the margin status was evaluated at completion of standard PM, prior to randomization to CSM versus no CSM. Non-parametric statistical analyses were performed using SPSS Version 26.

Results

Molecular subtype was significantly correlated with race ( P = .011), palpability ( P = .007), and grade ( P < .001). Subtype did not correlate with Hispanic ethnicity ( P = .760) or lymphovascular invasion ( P = .756). In this cohort, the overall positive margin rate was 33.7%. This did not vary based on molecular subtype (positive margin rate 33.7% for patients with luminal tumors vs 36.4% for those with TN tumors, P = .425).

Discussion

Molecular subtype does not predict margin status. Therefore, molecular subtype should not, independent of other factors, influence surgical decision-making.