Lumpectomy specimen margins are not reliable in predicting residual disease in breast conserving surgery

Intraoperative Fluorescence Guidance for Breast Cancer Lumpectomy Surgery

Fluorescence Guidance for Lumpectomy SurgeryThis prospective trial of 406 patients assessed margin status with and without pegulicianine fluorescence-guided surgery (pFGS) for stages 0 to 3 breast cancers. The use of pFGS met prespecified thresholds for removal of residual tumor and specificity but did not meet the prespecified threshold for sensitivity.

Does cavity margin shaving reduce residual tumor and re-excision rates? A systematic review

PURPOSE

Cavity shaving (CS) is a surgical technique used in the treatment of breast cancer (BC). It may reduce margin positivity in histologic assessment and consequently reduces re- excision rates in breast conserving surgery (BCS). The evidence for this assumption is described in the present review.

METHODS

A systematic review of relevant literature in English from January 1999 to April 2019 was conducted. The analysis included studies on CS and its effects on re-excision rates and margin positivity. We searched PubMed databases for relevant publications. In total, 22 studies were included in the present review.

RESULTS

The benefit from CS on re-excision rates and histologic margin positivity was variable. Out of 22 studies, 17 reported a reduction in both re-excision rates and histologic margin positivity in margin shaved patients. Four studies could not find a significant reduction of second surgeries and residual tumor rates. One study suggested that CS after BCS was superior to single BCS only in subgroup analysis in IDC tumors.

CONCLUSION

CS is a surgical technique that was shown to reduce re-excision and margin positivity rates in most of the studies. Furthermore, it can be a useful tool to assess specimen margins and detect multifocality.

Cysteine Cathepsins in Breast Cancer: Promising Targets for Fluorescence-Guided Surgery

The majority of breast cancer patients is treated with breast-conserving surgery (BCS) combined with adjuvant radiation therapy. Up to 40% of patients has a tumor-positive resection margin after BCS, which necessitates re-resection or additional boost radiation. Cathepsin-targeted near-infrared fluorescence imaging during BCS could be used to detect residual cancer in the surgical cavity and guide additional resection, thereby preventing tumor-positive resection margins and associated mutilating treatments. The cysteine cathepsins are a family of proteases that play a major role in normal cellular physiology and neoplastic transformation. In breast cancer, the increased enzymatic activity and aberrant localization of many of the cysteine cathepsins drive tumor progression, proliferation, invasion, and metastasis. The upregulation of cysteine cathepsins in breast cancer cells indicates their potential as a target for intraoperative fluorescence imaging. This review provides a summary of the current knowledge on the role and expression of the most important cysteine cathepsins in breast cancer to better understand their potential as a target for fluorescence-guided surgery (FGS). In addition, it gives an overview of the cathepsin-targeted fluorescent probes that have been investigated preclinically and in breast cancer patients. The current review underscores that cysteine cathepsins are highly suitable molecular targets for FGS because of favorable expression and activity patterns in virtually all breast cancer subtypes. This is confirmed by cathepsin-targeted fluorescent probes that have been shown to facilitate in vivo breast cancer visualization and tumor resection in mouse models and breast cancer patients. These findings indicate that cathepsin-targeted FGS has potential to improve treatment outcomes in breast cancer patients.

Clinical Impact of Intraoperative Margin Assessment in Breast-Conserving Surgery With a Novel Pegulicianine Fluorescence-Guided System: A Nonrandomized Controlled Trial

Importance

Positive margins following breast-conserving surgery (BCS) are often identified on standard pathology evaluation. Intraoperative assessment of the lumpectomy cavity has the potential to reduce residual disease or reexcision rate following standard of care BCS in real time.

Objective

To collect safety and initial efficacy data on the novel pegulicianine fluorescence-guided system (pFGS) when used to identify residual cancer in the tumor bed of female patients undergoing BCS.

Design, Setting, and Participants

This prospective single-arm open-label study was conducted as a nonrandomized multicenter controlled trial at 16 academic or community breast centers across the US. Female patients 18 years and older with newly diagnosed primary invasive breast cancer or ductal carcinoma in situ DCIS undergoing BCS were included, excluding those with previous breast cancer surgery and a history of dye allergies. Of 283 consecutive eligible patients recruited, 234 received a pegulicianine injection and were included in the safety analysis; of these, 230 were included in the efficacy analysis. Patients were enrolled between February 6, 2018, and April 10, 2020, and monitored for a 30-day follow-up period. Data were analyzed from April 10, 2020, to August 5, 2021.

Interventions

Participants received an injection of a novel imaging agent (pegulicianine) a mean (SD) of 3.2 (0.9) hours prior to surgery at a dose of 1 mg/kg. After completing standard of care (SOC) excision, pFGS was used to scan the lumpectomy cavity to guide the removal of additional shave margins.

Main Outcomes and Measures

Adverse events and sensitivity, specificity, and reexcision rate.

Results

Of 234 female patients enrolled (median [IQR] age, 62.0 [55.0-69.0] years), 230 completed the trial and 1 patient with a history of allergy to contrast agents had an anaphylactic reaction and recovered without sequelae. Correlation of pFGS with final margin status on a per-margin analysis showed a marked improvement in sensitivity over standard pathology assessment of the main lumpectomy specimen (69.4% vs 38.2%, respectively). On a per-patient level, the false-negative rate of pFGS was 23.7% (9 of 38), and sensitivity was 76.3% (29 of 38). Among 32 patients who underwent excision of pFGS-guided shaves, pFGS averted the need for reexcision in 6 (19%).

Conclusions and Relevance

In this pilot feasibility study, the safety profile of pegulicianine was consistent with other imaging agents used in BCS, and was associated with a reduced need for second surgery in patients who underwent intraoperative additional excision of pFGS-guided shaves. These findings support further development and clinical performance assessment of pFGS in a prospective randomized trial.

Trial Registration

ClinicalTrials.gov Identifier: NCT03321929.

Resection of Cavity Shave Margins in Stage 0-III Breast Cancer Patients Undergoing Breast Conserving Surgery: A Prospective Multicenter Randomized Controlled Trial

OBJECTIVE

Single-center studies have demonstrated that resection of cavity shave margins (CSM) halves the rate of positive margins and re-excision in breast cancer patients undergoing partial mastectomy (PM). We sought to determine if these findings were externally generalizable across practice settings.

METHODS

In this multicenter randomized controlled trial occurring in 9 centers across the United States, stage 0-III breast cancer patients undergoing PM were randomly assigned to either have resection of CSM ("shave" group) or not ("no shave" group). Randomization occurred intraoperatively, after the surgeon had completed their standard PM. Primary outcome measures were positive margin and re-excision rates.

RESULTS

Between July 28, 2016 and April 13, 2018, 400 patients were enrolled in this trial. Four patients (2 in each arm) did not meet inclusion criteria after randomization, leaving 396 patients for analysis: 196 in the "shave" group and 200 to the "no shave" group. Median patient age was 65 years (range; 29-94). Groups were well matched at baseline for demographic and clinicopathologic factors. Prior to randomization, positive margin rates were similar in the "shave" and "no shave" groups (76/196 (38.8%) vs. 72/200 (36.0%), respectively, P = 0.604). After randomization, those in the "shave" group were significantly less likely than those in the "no shave" group to have positive margins (19/196 (9.7%) vs. 72/200 (36.0%), P < 0.001), and to require re-excision or mastectomy for margin clearance (17/196 (8.7%) vs. 47/200 (23.5%), P < 0.001).

CONCLUSION

Resection of CSM significantly reduces positive margin and re-excision rates in patients undergoing PM.

Performance of a novel protease-activated fluorescent imaging system for intraoperative detection of residual breast cancer during breast conserving surgery

Purpose

Safe breast cancer lumpectomies require microscopically clear margins. Real-time margin assessment options are limited, and 20–40% of lumpectomies have positive margins requiring re-excision. The LUM Imaging System previously showed excellent sensitivity and specificity for tumor detection during lumpectomy surgery. We explored its impact on surgical workflow and performance across patient and tumor types.

Methods

We performed IRB-approved, prospective, non-randomized studies in breast cancer lumpectomy procedures. The LUM Imaging System uses LUM015, a protease-activated fluorescent imaging agent that identifies residual tumor in the surgical cavity walls. Fluorescent cavity images were collected in real-time and analyzed using system software.

Results

Cavity and specimen images were obtained in 55 patients injected with LUM015 at 0.5 or 1.0 mg/kg and in 5 patients who did not receive LUM015. All tumor types were distinguished from normal tissue, with mean tumor:normal (T:N) signal ratios of 3.81–5.69. T:N ratios were 4.45 in non-dense and 4.00 in dense breasts (p = 0.59) and 3.52 in premenopausal and 4.59 in postmenopausal women (p = 0.19). Histopathology and tumor receptor testing were not affected by LUM015. Falsely positive readings were more likely when tumor was present < 2 mm from the adjacent specimen margin. LUM015 signal was stable in vivo at least 6.5 h post injection, and ex vivo at least 4 h post excision.

Conclusions

Intraoperative use of the LUM Imaging System detected all breast cancer subtypes with robust performance independent of menopausal status and breast density. There was no significant impact on histopathology or receptor evaluation.

Impact of systematic cavity shave margins in breast-conserving surgery at a large community hospital with a low baseline re-excision rate

Systematic cavity shave margins (CSM) can decrease rate of positive margins and re-excision beyond that of selective CSM. The objective of this study was to determine whether systematic CSM decreased re-excision rate in a population with a low baseline re-excision rate. We conducted a retrospective chart review of patients who underwent breast-conserving surgery (BCS) from November 2013 to November 2017. Primary end points were re-excision rate and margin status. Secondary end points were total volume of tissue excised, operative time, and concordance of core needle biopsy (CNB) pathology with final surgical pathology. The re-excision rates were 14.29% in the no shave margin group; 15.38% in the selective CSM; and 14.59% in the systematic CSM (P = .985). Odds of re-excision with ductal carcinoma in situ (DCIS) was 5.04 times greater than with invasive cancer (INV) and 1.94 times higher than with INV and DCIS. There was no significant difference in positive margins between groups (P = .362). Mean specimen volume was lowest in the systematic CSM group (64.6 cm³ ), compared to no CSM and selective CSM (94.6 cm³ and 91.8 cm³ , respectively). With inclusion of shave margin volumes, total volume removed was not significantly different between no shave margin group (94.6 cm³ ) and systematic CSM (89.7 cm³ ) (P = .949). For patients with invasive ductal carcinoma (IDC) alone on their initial biopsy pathology, 69% were discovered to also have DCIS upon final pathology. Re-excision rate and specimen volume between all groups were not statistically different. There was a higher re-excision rate when DCIS was present, especially when not identified on CNB. As systematic CSM is most impactful when DCIS is involved, it is important to establish its presence for proper surgical planning.

Feasibility Study of a Novel Protease-Activated Fluorescent Imaging System for Real-Time, Intraoperative Detection of Residual Breast Cancer in Breast Conserving Surgery

BACKGROUND

Obtaining tumor-free margins is critical to prevent recurrence after lumpectomy for breast cancer. Unfortunately, current approaches leave positive margins that require second surgeries in 20-40% of patients. We assessed the LUM Imaging System for real-time, intraoperative detection of residual tumor.

METHODS

Breast lumpectomy cavity walls and excised specimens were assessed with the LUM Imaging System after 1 mg/kg intravenous LUM015, a protease-activatable fluorescent agent. Fluorescence at potential sites of residual tumor in lumpectomy cavity walls was evaluated intraoperatively with a sterile hand-held probe, with real-time predictive results displayed on a monitor intraoperatively, and later correlated with histopathology.

RESULTS

In vivo lumpectomy cavities and excised specimens were imaged after LUM015 injection in 45 women undergoing breast cancer surgery. Invasive ductal and lobular cancers and intraductal cancer (DCIS) were included. A total of 570 cavity margin surfaces in 40 patients were used for algorithm development. Image analysis and display took approximately 1 s per 2.6-cm-diameter circular margin surface. All breast cancer subtypes could be distinguished from adjacent normal tissue. For all imaged cavity surfaces, sensitivity for tumor detection was 84%. Among 8 patients with positive margins after standard surgery, sensitivity for residual tumor detection was 100%; 2 of 8 were spared second surgeries because additional tissue was excised at sites of LUM015 signal. Specificity was 73%, with some benign tissues showing elevated fluorescent signal.

CONCLUSIONS

The LUM015 agent and LUM Imaging System allow rapid identification of residual tumor in the lumpectomy cavity of breast cancer patients and may reduce rates of positive margins.

Involved margins after lumpectomy for breast cancer: Always to be re-excised?

BACKGROUND

The oncologic benefit of upfront re-excision of involved margins after breast-conserving surgery in the context of current multimodal clinical management of breast cancer is unclear. The aim of the present study was to assess the 5-years locoregional recurrence (LRR)-free and distant metastases (DM)-free survival probabilities in patients not undergoing re-excision of positive margins after lumpectomy for breast cancer.

METHODS

A cohort of 104 patients with positive margins not undergoing re-excision was matched by propensity score with a cohort of 2006 control patients with clear margins after breast-conserving surgery, treated between 2008 and 2018. A multivariate survival analysis was performed accounting for all variables related to LRR and DM, including adjuvant treatments.

RESULTS

After adjusting for potential confounders, avoiding to re-excise a positive margin after lumpectomy had no effect on 5-years LRR-free survival probability (HR 0.98, 95%CI 0.36-2.67, p = 0.96) or 5-years DM-free survival probability (HR 0.37, 95%CI 0.08-1.61, p = 0.18). No correlation was found between occurrence of LRR and number of involved margins (HR 1.28, 95%CI 0.10-12.4, Log-rank p = 0.83), or extension of infiltrating disease (HR 1.21, 95%CI 0.20-7.40, Log-rank p = 0.83), but a trend toward higher LRR probability was found for invasive ductal (HR 6.92, 95%CI 0.7-68.8, Log-rank p = 0.10) and invasive lobular cancer (HR 12.95, 95%CI 0.79-213.6, Log-rank p = 0.07) on positive margins.

CONCLUSIONS

In the era of multimodal treatment of breast cancer and accurate strategies to reduce the probability of residual disease in the post-lumpectomy cavity, re-excision of positive margins might be omitted in selected patients with low-risk breast cancers.

Micro-computed tomography enables rapid surgical margin assessment during breast conserving surgery (BCS): correlation of whole BCS micro-CT readings to final histopathology

Background

Roughly 23% of breast conserving surgery (BCS) patients undergo a second re-excision procedure due to pathologically positive surgical margins. We investigated the feasibility and potential value of micro-Computed Tomography (micro-CT) as a surgical margin guidance tool during BCS.

Methods

A cohort of 32 BCS specimens was prospectively imaged with a pre-clinical micro-CT system upon arrival in the surgical pathology laboratory. Reconstructed micro-CT scans were evaluated retrospectively by an experienced breast radiologist, who provided binary determinations whether lesions extended to the specimen margin. These readings were then compared to the final pathological diagnosis and to 2D specimen radiography readings.

Results

Of the 32 specimens imaged, 28 had malignant and four had benign pathological diagnoses. Overall five (four malignant, one benign) of the 32 specimens had lesion tissue extending to the margin. For all 32 specimens, micro-CT reconstructions were calculated (< 4 min. acquisition + reconstruction time) and each specimen was volumetrically analyzed by a radiologist. Of the 28 malignant specimen readings, 18 matched the final pathological diagnosis [64%, 95 CI (47%–81%)], with a negative predictive value of 89% [95 CI (74%–96%)]. Micro-CT readings revealed changes in the tumor location and margin status as compared to single-projection radiography readings.

Conclusions

Micro-CT scanning of BCS specimens enabled margin status assessment over the entirety of the surgical surface in a clinically relevant time frame, provided additional spatial information over single-projection radiography, and may be a potentially useful BCS guidance tool.

Electronic supplementary material

The online version of this article (10.1007/s10549-018-4951-3) contains supplementary material, which is available to authorized users.

Real-time, intraoperative detection of residual breast cancer in lumpectomy cavity walls using a novel cathepsin-activated fluorescent imaging system

PURPOSE

Obtaining tumor-free surgical margins is critical to prevent recurrence in breast-conserving surgery but it remains challenging. We assessed the LUM Imaging System for real-time, intraoperative detection of residual tumor.

METHODS

Lumpectomy cavity walls and excised specimens of breast cancer lumpectomy patients were assessed with the LUM Imaging System (Lumicell, Inc., Wellesley MA) with and without intravenous LUM015, a cathepsin-activatable fluorescent agent. Fluorescence at potential sites of residual tumor was evaluated with a sterile hand-held probe, displayed on a monitor and correlated with histopathology.

RESULTS

Background autofluorescence was assessed in excised specimens from 9 patients who did not receive LUM015. In vivo lumpectomy cavities and excised specimens were then imaged in 15 women undergoing breast cancer surgery who received no LUM015, 0.5, or 1 mg/kg LUM015 (5 women per dose). Among these, 11 patients had invasive carcinoma with ductal carcinoma in situ (DCIS) and 4 had only DCIS. Image acquisition took 1 s for each 2.6-cm-diameter surface. No significant background normal breast fluorescence was identified. Elevated fluorescent signal was seen from invasive cancers and DCIS. Mean tumor-to-normal signal ratios were 4.70 ± 1.23 at 0.5 mg/kg and 4.22 ± 0.9 at 1.0 mg/kg (p = 0.54). Tumor was distinguished from normal tissue in pre-and postmenopausal women and readings were not affected by breast density. Some benign tissues produced fluorescent signal with LUM015.

CONCLUSION

The LUM Imaging System allows rapid identification of residual tumor in the lumpectomy cavity of breast cancer patients and may reduce rates of positive margins.

The importance of surgical margins in breast cancer

Achieving negative margins with "no tumor on ink" is an appropriate goal in breast conserving therapy (BCT). Wider margins do not decrease recurrence rates, and re-excision in patients with microscopic positive margins is warranted. Several strategies exist to increase rates of negative margins, including techniques to improve tumor localization, intraoperative assessment of margins and oncoplastic techniques. Negative margins should be the goal of BCT, as this will improve both local control and long-term survival.

A Randomized, Controlled Trial of Cavity Shave Margins in Breast Cancer

BACKGROUND

Routine resection of cavity shave margins (additional tissue circumferentially around the cavity left by partial mastectomy) may reduce the rates of positive margins (margins positive for tumor) and reexcision among patients undergoing partial mastectomy for breast cancer.

METHODS

In this randomized, controlled trial, we assigned, in a 1:1 ratio, 235 patients with breast cancer of stage 0 to III who were undergoing partial mastectomy, with or without resection of selective margins, to have further cavity shave margins resected (shave group) or not to have further cavity shave margins resected (no-shave group). Randomization occurred intraoperatively after surgeons had completed standard partial mastectomy. Positive margins were defined as tumor touching the edge of the specimen that was removed in the case of invasive cancer and tumor that was within 1 mm of the edge of the specimen removed in the case of ductal carcinoma in situ. The rate of positive margins was the primary outcome measure; secondary outcome measures included cosmesis and the volume of tissue resected.

RESULTS

The median age of the patients was 61 years (range, 33 to 94). On final pathological testing, 54 patients (23%) had invasive cancer, 45 (19%) had ductal carcinoma in situ, and 125 (53%) had both; 11 patients had no further disease. The median size of the tumor in the greatest diameter was 1.1 cm (range, 0 to 6.5) in patients with invasive carcinoma and 1.0 cm (range, 0 to 9.3) in patients with ductal carcinoma in situ. Groups were well matched at baseline with respect to demographic and clinicopathological characteristics. The rate of positive margins after partial mastectomy (before randomization) was similar in the shave group and the no-shave group (36% and 34%, respectively; P=0.69). After randomization, patients in the shave group had a significantly lower rate of positive margins than did those in the no-shave group (19% vs. 34%, P=0.01), as well as a lower rate of second surgery for margin clearance (10% vs. 21%, P=0.02). There was no significant difference in complications between the two groups.

CONCLUSIONS

Cavity shaving halved the rates of positive margins and reexcision among patients with partial mastectomy. (Funded by the Yale Cancer Center; ClinicalTrials.gov number, NCT01452399.).