Identifying Factors and Techniques to Decrease the Positive Margin Rate in Partial Mastectomies: Have We Missed the Mark?

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.

Invasive Lobular Carcinoma-Correlation Between Imaging and Final Pathology: Is MRI Better?

BACKGROUND

Invasive lobular carcinoma (ILC) is associated with high re-excision rates following breast-conserving surgery (BCS). The correlation between lesion size on different imaging modalities and final tumor size has not been well characterized.

METHODS

A prospective database of patients with stage I-III breast cancer undergoing BCS between 2006 and 2016 was reviewed. Pearson correlation analysis was used to correlate tumor size on breast imaging to final pathology.

RESULTS

Of these, 111 patients with ILC were identified. Mean lesion size was 1.93 cm for MMG, 1.61 cm for US, and 2.51 cm for MRI. Mean tumor size on surgical excision was 2.64 cm. The correlation coefficient between pathology and the different imaging modalities were as follows: MMG .17, US 0.37, and MRI .58. Actual tumor size was underestimated by 1 cm in 27.1% of MMGs, 50% of USs, and in 13.3% of MRIs. 38 patients (34.2%) underwent re-excision. No differences in re-excision rates were noted in patients with and without MRI, 30.3% vs 40.0%, respectively (P = .31).

CONCLUSION

While MRI provides a better estimate of tumor size than MMG and US, the size of the tumor on imaging only weakly correlated with pathology. The use of MRI does not decrease re-excision rates.

Preoperative non-palpable breast lesion localization, innovative techniques and clinical outcomes in surgical practice: A systematic review and meta-analysis

Pre-operative localization of non-palpable breast lesions with non-wired non-ionizing (NWNI) techniques may improve clinical outcomes as reoperation rate, cosmetic outcome and contribute to organizational aspects improvement in breast-conserving surgery (BCS). However only limited literature is available and clinical studies involving these forefront devices are often small and non-randomized. Furthermore, there is a lack of consensus on free margins and cosmetic outcomes definitions. The objective of the present meta-analysis was to determine the crude clinical outcomes reported for the NWNI techniques on BCS. A literature search was performed of PubMed, Embase and Scopus databases up to February 2021 in order to select all prospective or retrospective clinical trials on pre-operative breast lesion localization done with NWNI devices. All studies were assessed following the PRISMA recommendations. Continuous outcomes were described in averages corrected for sample size, while binomial outcomes were described using the weighted average proportion. Twenty-seven studies with a total of 2103 procedures were identified. The technique is consolidated, showing for both reflectors' positioning and localization nearly the 100% rate of success. The re-excision and clear margins rates were 14% (95% CI, 11-17%) and 87% (80-92%), respectively. Overall, positive margins rates were 12% (8-17%). In studies that compared NWNI and wire localization techniques, positive margin rate is lower for the first techniques (12%, 6-22% vs 17%, 12-23%) and re-excision rate is slightly higher using the latter (13%, 9-19% vs 16%, 13-18%). Pre-operative NWNI techniques are effective in the localization of non-palpable breast lesions and are promising in obtaining clear (or negative) margins minimizing the need for re-excision and improving the cosmetic outcomes. Randomized trials are needed to confirm these findings.

Clinical outcomes of an intraoperative surgical margin assessment using the fresh frozen section method in patients with invasive breast cancer undergoing breast-conserving surgery - a single center analysis

Breast conserving treatment (BCT) is a safe standard therapeutic method in patients with early invasive breast cancer. However, it is associated with an increased risk of residual neoplastic tissues in surgical margins. The aim of this study was to assess the outcome of the use of the intraoperative pathologic analysis by the frozen section (FS) method for evaluation of the extent of the primary lumpectomy. The study concerns a retrospective analysis of a group of 1102 patients who underwent BCT between Jan 2015 and Dec 2016. The assessment focused on the frequency of the intraoperative pathologic analysis of the primary lumpectomy extent (fresh frozen section method). The influence of the BCT specimen analysis method on the free margins width, as well as the rate and the cause of reoperation were evaluated. The intraoperative lumpectomy evaluation was performed in 45.8% (505/1102) of patients (Group I), while in the remaining 54.2% of the cases it was decided to abandon this procedure (Group II). Although in 72 (14.3%) patients the intraoperative analysis gave negative results, the margins contained residual tumor tissue (vs. 16.9% in Group II). In Group I, conversion from the previously planned BCT to mastectomy was necessary in 5.9% (30/505) patients (vs. 9.7% in Group II). The duration of surgery was 48.9 ± 17.3 minutes (Group I) and 42.9 ± 13.6 minutes (Group II). In patients undergoing BCT, the use of the intraoperative pathologic analysis by the FS method resulted in a reduction of the total number of reoperations performed due to residual tumor found in the margins following the primary lumpectomy. However, it statistically significantly extended the duration of the surgery.

Assessment of intraductal carcinoma in situ (DCIS) using grating-based X-ray phase-contrast CT at conventional X-ray sources: An experimental ex-vivo study

BACKGROUND

The extent of intraductal carcinoma in situ (DCIS) is commonly underestimated due to the discontinuous growth and lack of microcalcifications. Specimen radiography has been established to reduce the rate of re-excision. However, the predictive value for margin assessment with conventional specimen radiography for DCIS is low. In this study we assessed the potential of grating-based phase-contrast computed tomography (GBPC-CT) at conventional X-ray sources for specimen tomography of DCIS containing samples.

MATERIALS AND METHODS

GBPC-CT was performed on four ex-vivo breast specimens containing DCIS and invasive carcinoma of non-specific type. Phase-contrast and absorption-based datasets were manually matched with corresponding histological slices as the standard of reference.

RESULTS

Matching of CT images and histology was successful. GBPC-CT showed an improved soft tissue contrast compared to absorption-based images revealing more histological details in the same sections. Non-calcifying DCIS exceeding the invasive tumor could be correlated to areas of dilated bright ducts around the tumor.

CONCLUSIONS

GBPC-CT imaging at conventional X-ray sources offers improved depiction quality for the imaging of breast tissue samples compared to absorption-based imaging, allows the identification of diagnostically relevant tissue details, and provides full three-dimensional assessment of sample margins.

Oncoplastic breast conserving surgery with tailored needle-guided excision

Background

Breast conserving surgery (BCS) administered with oncoplastic approach (OBCS), when it is required, is currently the gold standard for the treatment of early breast cancer. Wire-guided localization (WL) is the most popular technique used to help surgeon in breast cancer excision. Currently, a universal and undeniable goal is to minimize the rate of positive margins and re-excision operation after BCS improving cosmetic outcome and decreasing health care costs. This study is aimed to report our experience combining OBCS and tailored WL as surgical approach for early breast cancers.

Methods

We performed a retrospective study on 148 breast cancer patients who were treated with OBCS and tailored WL, which consists in individualization of the number and location of wires depending on patient particularities, in our Breast Unit from March 2013 to December 2015. A multivariate analysis was used to determine the association between clinic-pathologic variables, which can be known preoperatively, and margin status.

Results

The rate of affected margins was 13.5% and 10.8% patients underwent re-interventions for oncologic reasons. Multifocality was strongly associated with involved margins [odds ratio (OR) 4.67].

Conclusions

OBCS together with tailored WL obtains an acceptable rate of positive margins and high rate of final BCS.