Shelley Hwang, MD MPH
Vice Chair of Research, Chief of Breast Surgical Oncology
Duke University
Durham, North Carolina, United States
Disclosure: Astra Zeneca (Individual(s) Involved: Self): Consultant; Clinetic (Individual(s) Involved: Self): steering committee; Higgs Boson (Individual(s) Involved: Self): steering committee; Immunis (Individual(s) Involved: Self): Consultant; Merck (Individual(s) Involved: Self): speakers' bureau
The objective of this study was to collect safety and efficacy data on pegulicianine fluorescence guided surgery (pFGS) for identifying residual cancer in the tumor bed of patients undergoing breast conserving surgery (BCS).
Methods:
This prospective, single arm, open-label feasibility study was conducted across 16 US sites. Female patients aged ≥18 years with newly diagnosed invasive or intraductal cancer undergoing BCS were injected intravenously with pegulicianine 4 ± 2 hours prior to surgery at a dose of 1.0 mg/kg. After tumor excision per standard of care (SOC), pFGS was used for identification and removal of residual cancer.
Results:
234 patients received pegulicianine and 230 completed pFGS. One patient experienced anaphylaxis during the administration of pegulicianine; she recovered without sequelae. pFGS prompted additional margin excisions in 138 patients; residual tumor was found in 26 (19%). Negative margins after SOC BCS were achieved in 192/230 (83.5%) patients. pFGS guided excision of residual tumor in 14/192 (7.3%) patients with negative SOC margins. In these 14 patients, pFGS guided removal of residual tumor that would have otherwise remained in the patient. Among the 38 patients with positive margins after SOC BCS, 23 had pFGS shaves; 6 of these patients (15.8%) were converted to negative margins on final pathology. In 3 additional patients with positive SOC BCS margins, pFGS recommended further excision, but these were not performed based upon surgeon judgement. The overall final positive margin rate after pFGS was 15% (35/230). The overall sensitivity, specificity, and negative predictive value of pFGS were 69.4%, 70.4% and 98.3% respectively.
Conclusions:
Residual tumor was removed after SOC BCS in 19% of patients who underwent an additional margin excision for a positive pFGS signal. The safety profile of pegulicianine was excellent and consistent with other imaging agents used in BCS. These findings, including a notably high negative predictive value, support further clinical assessment of pFGS which is currently being conducted in a prospective randomized trial (“INSITE”, NCT03686215).