Abstract 44P
Background
Circulating tumor cells (CTC) detection has proven to be an important parameter for predicting progression-free and overall survival. CTCs provide a so-called real-time liquid biopsy which gives better opportunities for selection of treatment.
Methods
A prospective observational study conducted the Rajiv Gandhi Cancer Institute & Research Centre, New Delhi. 36 treatment naïve patients of metastatic breast cancer were enrolled from April 2016 and May 2018. CTCs were detected using Cellsearch system. Correlation of CTCs with patient’s outcome after chemotherapy in terms of progression-free survival (PFS) and overall survival (OS) were calculated at one year. The level of CTCs in peripheral blood was measured at baseline before chemotherapy and then at 1 month and 6 months of treatment. All patients underwent PET-CT scan at 3 months and 6 months of treatment.
Results
36 patients were included in this study. The mean CTCs at baseline was 13.8 (0-48), with 75% of patients having CTC ≥5. A positive correlation with the number of sites of metastasis with the number of CTCs was noted (p < 0.001 and R = 0.886). Around 11% of the patients had a complete response (CR) after 3 months of therapy as determined by imaging with a mean number of CTCs 21 (median 17) before starting the treatment and 4.25 (median 4.5) at 1 month (P = 0.14). Similarly, partial response at 3 months, the mean CTCs significantly decreased to 6.3 from 12.9 (p = 0.001). Patients with baseline CTCs<5 had a mean PFS of 9.8 months (95% CI of 7.2 to 12.3) and patients with baseline CTCs ≥5 had a mean PFS of 8.6 months (95% CI of 7.1 to 10.1) (p = 0.37). Patients with CTCs < 5 after one month of treatment had a mean OS of 11.6 months (95% CI of 10.8 to 12.4) and patients with CTCs≥5 after one of treatment had a mean overall survival of 9.6 months (95% CI of 8.0 to 11.2) (p = 0.08).
Conclusions
Our results have implications for both standard care and clinical research in developing countries. More accurate determination of treatment effectiveness early in the course of therapy might spare patient therapy-related toxicity from futile therapy, patient families from financial toxicity and allow treatment to be changed to a more effective regimen.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Rajiv Gandhi Cancer Institute and Research Centre, New Delhi.
Funding
Rajiv Gandhi Cancer Institute and Research Centre, New Delhi.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
508P - Efficacy and safety of anti-PD-1 antibody SHR-1210 combined with apatinib in first-line treatment for advanced lung squamous carcinoma: A phase II study
Presenter: Jinliang Wang
Session: Poster display session
Resources:
Abstract
525P - Retrospective analysis of outcomes of cisplatin and irinotecan combination chemotherapy for unresectable thymic carcinoma
Presenter: Akito Fukuda
Session: Poster display session
Resources:
Abstract
524P - A study in recurrent small cell lung cancer patients, comparing weekly paclitaxel, irinotecan and temozolomide in second-line: A prospective study from a south Indian tertiary cancer hospital
Presenter: LALATENDU MOHARANA
Session: Poster display session
Resources:
Abstract
505P - PD-L1 expression in ALK rearranged NSCLC: All questions answered?
Presenter: Amrith B P
Session: Poster display session
Resources:
Abstract
487P - Afatinib versus gefitinib or erlotinib in first-line setting for Malaysia patients with EGFR mutant advanced lung adenocarcinoma
Presenter: Chee Shee Chai
Session: Poster display session
Resources:
Abstract
492P - Feasibility of rebiopsy and sequential treatment of EGFR tyrosine kinase inhibitors in real world patients with EGFR mutant non-small cell lung cancer
Presenter: Heekyung Ahn
Session: Poster display session
Resources:
Abstract
513P - Phase II study of vitamin B12 and folate supplementation for patients undergoing chemotherapy with pemetrexed
Presenter: Shingo Kitagawa
Session: Poster display session
Resources:
Abstract
493P - Is exon 19 deletion different from exon 21 mutation in advanced non-small cell lung cancer: A single centre experience
Presenter: Sarita Shrivastva
Session: Poster display session
Resources:
Abstract
494P - Comparison of pattern of disease progression and prevalence of acquired T790M mutation in Malaysia patients with EGFR mutant lung adenocarcinoma upon failure of first-line afatinib, gefitinib and erlotinib
Presenter: Chee Shee Chai
Session: Poster display session
Resources:
Abstract
517P - High BRCA1 expression is independently correlated with decreased overall survival in lung adenocarcinoma: Evidence from meta and bioinformatics analyses
Presenter: Fengzhu Guo
Session: Poster display session
Resources:
Abstract