Abstract P3-01-09: A phase I clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer

Abstract

Abstract Background: Combined use of a radiocolloid and a vital blue dye is recommended for accurate lymphatic mapping and sentinel lymph node (SLN) identification. However, vital blue dyes can cause tattooing, skin necrosis and allergic reactions. Hence, there is a great need for new lymphatic mapping agents. Here we describe the novel use of VST-1001 (dilute fluorescein) and direct visualization devices in lymphatic mapping and SLN identification. Methods: A prospective, non randomized, single arm, open label, single dose, dose-finding Phase I clinical trial in patients (pts) with high-grade DCIS and clinical stage I/II breast cancer eligible for SLN biopsy was performed. All pts had SLN localization with technetium-99m-sulfur colloid (Tc99mSC) and intraoperative lymphatic mapping with VST-1001 injected peritumorally, periareolarly, and/or intradermally. SLN radioactivity was identified with a gamma probe, and VST-1001 fluorescence was induced by light emitting diodes and detected as a yellowish-green fluorescence in the visible light range with notch filter spectacles. The primary endpoints were safety, ability of VST 1001 to localize lymph nodes, and the optimal dose of VST-1001. SLN concordance of Tc99mSC radioactivity and VST-1001 fluorescence was also assessed. Results: Fifteen women with a median age of 60 yrs (range, 43-80) were enrolled. In cohort 1, 5 pts received 0.01% VST-1001. All patients had at least 1 SLN that was fluorescent and radioactive. A total of 22 SLNs were identified, many with faint fluorescence. Per protocol, the dose of VST-1001 was increased, and in cohort 2, 10 patients received 0.1% VST-1001. All 10 (100%) pts in cohort 2 had at least 1 SLN that was fluorescent and radioactive. Of a total of 24 SLNs identified, 20 (83%) were fluorescent and radioactive, 2 (8%) were radioactive only, and 2 (8%) were fluorescent only. Four SLNs in 3 patients contained micrometastatic breast cancer; all 4 SLNs were radioactive and fluorescent. There were no adverse events related to VST-1001. A Phase II clinical trial is currently accruing. Conclusions: VST-1001 safely localized lymph nodes in breast cancer. VST-1001 was able to localize lymph nodes that were not radioactive and had a high concordance with Tc99mSC. VST-1001 may be a novel alternative to vital blue dyes in lymphatic mapping and lymph node localization. Citation Format: Ross MI, Bedrosian I, Black DM, Mittendorf EA, Caudle AS, Babiera GV, Hwang RF, Meric-Bernstam F, Grissom CB, Brulotte M, Andtbacka RHI. A phase I clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-01-09.