Abstract 2219
Background
Racotumomab is an anti-idiotype vaccine, a mirror image of N-Glycolylneuraminic acid (NeuGcGM3), which mimics this ganglioside and triggers an immune response in various tumors. In this study we investigated the prognostic significance of tissue NeuGcGM3 expression level and prognostic as well as predictive value of circulating tumor cell count monitoring in patients on Racotumomab treatment.
Methods
Out of 48 patients characterized, 40 were non-small cell lung cancer (NSCLC), 12 stage III and 28 stage IV. 19 Adenocarcinoma and 21 Squamous Ca. 2 were small cell lung cancer (SCLC) and 6 with other carcinomas. Male/Female ratio was 3.36(37/11) and median age was 63 (31-84). All patients received Racotumomab as switch maintenance after chemotherapy. 7 PD-L1 (+) Pts also received check point inhibitors on progression. Expression of NeuGcGM3 was detected with 14F7 monoclonal antibody IHC staining and graded as 0,1+,2+ or 3+ according to intensity. Circulating tumor cell (CTC) count was monitored using Cell Sorter throughout the treatment course, before starting Racotumomab and every 3 months or on clinical progression.
Results
NeuGcGM3 IHC were performed 25 out of 48 patients whose paraffin blocks were available. 9 Patients had strong (3+), 12 had (2+) and 4 patients had (1+) NeuGcGM3 staining intensity. There was no statistically significant difference in the mean overall survival of the patients according to IHC staining level (1+) mean OS:55.3 months, (2+) mean OS:40.9 months, and (3+) OS:39.0 months. In 14 Patients, circulating tumor cell count was monitored from the blood and correlated well with clinical outcomes in 11 out of 14 patients (%78.5). Significant reduction of the CTC counts was compatible with clinical response whereas increased CTC counts were early messengers for clinical progression.
Conclusions
This study revealed that any grade of NeuGcGM3 positivity in the tumor tissue is adequate to select a patient for Racotumomab treatment regardless of the IHC intensity. We also concluded that CTC monitoring in patients receiving immunotherapy is a good predictive and prognostic tool.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Necdet Uskent.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5877 - Efficacy of anti-PD(L)1 treatment in patients with metastatic urothelial cancer based on mRNA- and protein- based PD-L1 determination: Results from the multicentric, retrospective FOsMIC trial
Presenter: Jonas Jarczyk
Session: Poster Display session 3
Resources:
Abstract
5204 - A differential bladder microbiota composition is associated with tumor grade in bladder cancer.
Presenter: Monica Parra-Grande
Session: Poster Display session 3
Resources:
Abstract
4904 - Molecular characterization of metastatic urothelial carcinoma (mUC) in prior or current smokers (PCS) vs non-smokers (NS)
Presenter: Victor Sacristan Santos
Session: Poster Display session 3
Resources:
Abstract
5370 - Evaluation of different diagnostic methods for identification of FGFR alteration in advanced urothelial carcinomas: Proficiency Results based on multiple RNA extraction kits and mutation detection methods
Presenter: Veronika Weyerer
Session: Poster Display session 3
Resources:
Abstract
2579 - Title: Genomic characterization of non-schistosomiasis-related squamous cell carcinoma (NSR-SCC) of the urinary bladder: a retrospective study of potential prognostic and predictive biomarkers
Presenter: Esmail Al-ezzi
Session: Poster Display session 3
Resources:
Abstract
2203 - TiNivo: Tivozanib combined with nivolumab results in prolonged progression free survival in patients with metastatic renal cell carcinoma (mRCC). Final Results.
Presenter: Philippe Barthelemy
Session: Poster Display session 3
Resources:
Abstract
4712 - First-Line Pembrolizumab (pembro) Monotherapy for Advanced Non‒Clear Cell Renal Cell Carcinoma (nccRCC): Updated Follow-Up for KEYNOTE-427 Cohort B
Presenter: Cristina Suárez
Session: Poster Display session 3
Resources:
Abstract
2091 - First-Line Pembrolizumab (pembro) Monotherapy in Advanced Clear Cell Renal Cell Carcinoma (ccRCC): Updated Follow-Up For KEYNOTE-427 Cohort A
Presenter: James Larkin
Session: Poster Display session 3
Resources:
Abstract
2368 - Association Between Depth of Response and Overall Survival: Exploratory Analysis in Patients With Previously Untreated Advanced Renal Cell Carcinoma (aRCC) in CheckMate 214
Presenter: Viktor Grünwald
Session: Poster Display session 3
Resources:
Abstract
6008 - Quality of life in previously untreated patients with advanced renal cell carcinoma (aRCC) in CheckMate 214: updated results
Presenter: David Cella
Session: Poster Display session 3
Resources:
Abstract