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.

Phase II Study of Gemcitabine, Carboplatin, and Iniparib As Neoadjuvant Therapy for Triple-Negative and BRCA1/2 Mutation-Associated Breast Cancer With Assessment of a Tumor-Based Measure of Genomic Instability: PrECOG 0105.

PURPOSE: This study was designed to assess efficacy, safety, and predictors of response to iniparib in combination with gemcitabine and carboplatin in early-stage triple-negative and BRCA1/2 mutation-associated breast cancer. PATIENTS AND METHODS: This single-arm phase II study enrolled patients with stage I to IIIA (T ≥ 1 cm) estrogen receptor-negative (≤ 5%), progesterone receptor-negative (≤ 5%), and human epidermal growth factor receptor 2-negative or BRCA1/2 mutation-associated breast cancer. Neoadjuvant gemcitabine (1,000 mg/m(2) intravenously [IV] on days 1 and 8), carboplatin (area under curve of 2 IV on days 1 and 8), and iniparib (5.6 mg/kg IV on days 1, 4, 8, and 11) were administered every 21 days for four cycles, until the protocol was amended to six cycles. The primary end point was pathologic complete response (no invasive carcinoma in breast or axilla). All patients underwent comprehensive BRCA1/2 genotyping, and homologous recombination deficiency was assessed by loss of heterozygosity (HRD-LOH) in pretreatment core breast biopsies. RESULTS: Among 80 patients, median age was 48 years; 19 patients (24%) had germline BRCA1 or BRCA2 mutations; clinical stage was I (13%), IIA (36%), IIB (36%), and IIIA (15%). Overall pathologic complete response rate in the intent-to-treat population (n = 80) was 36% (90% CI, 27 to 46). Mean HRD-LOH scores were higher in responders compared with nonresponders (P = .02) and remained significant when BRCA1/2 germline mutations carriers were excluded (P = .021). CONCLUSION: Preoperative combination of gemcitabine, carboplatin, and iniparib is active in the treatment of early-stage triple-negative and BRCA1/2 mutation-associated breast cancer. The HRD-LOH assay was able to identify patients with sporadic triple-negative breast cancer lacking a BRCA1/2 mutation, but with an elevated HRD-LOH score, who achieved a favorable pathologic response. Confirmatory controlled trials are warranted.

Ex vivo Evans blue assessment of the blood brain barrier in three breast cancer brain metastasis models.

The limited entry of anticancer drugs into the central nervous system represents a special therapeutic challenge for patients with brain metastases and is primarily due to the blood brain barrier (BBB). Albumin-bound Evans blue (EB) dye is too large to cross the BBB but can grossly stain tissue blue when the BBB is disrupted. The course of tumor development and the integrity of the BBB were studied in three preclinical breast cancer brain metastasis (BCBM) models. A luciferase-transduced braintropic clone of MDA-231 cell line was used. Nude mice were subjected to stereotactic intracerebral inoculation, mammary fat pad-derived tumor fragment implantation, or carotid artery injections. EB was injected 30 min prior to euthanasia at various timepoints for each of the BCBM model animals. Serial bioluminescent imaging demonstrated exponential tumor growth in all models. Carotid BCBM appeared as diffuse multifocal cell clusters. EB aided the localization of metastases ex vivo. Tumor implants stained blue at 7 days whereas gross staining was not evident until day 14 in the stereotactic model and day 28 for the carotid model. EB assessment of the integrity of the BBB provides useful information relevant to drug testing in preclinical BCBM models.