Abstract 115P
Background
Tumour microenvironment is crucial for skin cancer progression, metastasizing and response to immunotherapy. Reflectance confocal microscopy (RCM) is a non-invasive in vivo method enabling skin cancer diagnostics and observation of inflammatory infiltrates in near histological resolution. The aim of the study is to describe the changes of microscopic criteria (by RCM and optical histology) in NMSC, stroma, and inflammatory infiltrates during the balstilimab (AGEN2034) therapy to evaluate the practical prediction attitude and repeatability of RCM.
Methods
Thirteen patients with NMSC (BCC, SCC, Adnexal carcinoma) enrolled in an open-label phase-II study (AGENONMELA; ABM_01_00004_03). RCM was performed in 8/13 patients in 2 parts of neoplasm on screening and/or week12 visits (2 patients had 2 RCM and 6 patients had a single RCM examination). In 13 patients were performed biopsies of corresponding areas for HP and translational tests were on the same visits.
Results
The inflammatory infiltrates were visualized in 12/12 lesions during the SCR and in 6/6 lesions on W12 visit in peripheral (epidermis, DEJ), perivascular, and/or peri/intra-tumour locations. Its mixed, neutrophilic or lymphocytic composition was confirmed in both methods. In complete response, an excellent RCM-HP correlation was observed. The partial regression of cancer was observed with concomitant differences in TILs and stroma with correspondence to HP.
Conclusions
The penetration limits RCM utility up to a depth of 200-300um. Further studies on the larger group of patients are needed to confirm the RCM accuracy in the prediction of histological findings, demonstrating its possible role in the observation of NMSC changes under immunotherapy. RCM is valuable in vivo method to monitor the response of NMSCs to immunotherapy, which may have applications in clinical practice.
Clinical trial identification
AGENONMELA; ABM_01_00004_03.
Legal entity responsible for the study
Early Phase Research Center, Maria Skłodowska-Curie National Research Institute, National Institute of Oncology, Warsaw, Poland.
Funding
Medical Research Agency, Poland Agenus Inc.
Disclosure
M.A. Slowinska: Financial Interests, Personal, Advisory Board: Takeda, Novartis, BMS; Financial Interests, Personal, Invited Speaker: Takeda, Novartis, Roche, Medac, BMS. A. Szumera-Cieckiewicz: Financial Interests, Personal, Research Grant: Agenus. M. Chelstowska: Financial Interests, Personal, Research Grant: Agenus. A. Dawidowska: Financial Interests, Personal, Research Grant: Agenus. S. Jaczewska: Financial Interests, Personal, Research Grant: Agenus. P. Rutkowski: Financial Interests, Personal, Invited Speaker, honoraria for lectures: MSD, BMS, Pierre Fabre; Financial Interests, Personal, Advisory Board: MSD, BMS, Pierre Fabre, Merck, Sanofi, Blueprint Medicines, Philogen; Financial Interests, Personal, Invited Speaker: Merck, Sanofi, Novartis; Financial Interests, Institutional, Research Grant, research grant for ISS: Pfzer; Financial Interests, Institutional, Funding, research grant for institution: BMS; Non-Financial Interests, Personal, Invited Speaker: Polish Society of Surgical Oncology; Non-Financial Interests, Personal, Officer: ASCO; Non-Financial Interests, Personal, Invited Speaker, President Elect: Polish Oncological Society. I. Lugowska: Financial Interests, Personal, Invited Speaker, The reports of clinical trials: Roche, BMS, Macrogenics, Amgen; Financial Interests, Institutional, Other, Research grants: Roche; Financial Interests, Institutional, Other, Research grant: Agenus; Financial Interests, Personal and Institutional, Invited Speaker: Agenus, Roche, BMS, Janssen, Astra, Incyte, Macrogenics, Checkpoint Inhibitors, Celon, Pfizer, MSD, Debio; Non-Financial Interests, Personal, Project Lead: MSCI; Non-Financial Interests, Personal, Advisory Role, Board Member: EORTC. All other authors have declared no conflicts of interest.