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
511P - Phase II trial of carboplatin, nab-paclitaxel and bevacizumab for advanced non-squamous non-small cell lung cancer (CARNAVAL study; TORG1424/OLCSG1402)
Presenter: Toshio Kubo
Session: Poster display session
Resources:
Abstract
485P - A real-world experience of first-line afatinib in Korean patients with EGFR-mutant non-small cell lung cancer
Presenter: Seong Hoon Yoon
Session: Poster display session
Resources:
Abstract
522P - Weekly nab-PTX and weekly PTX for relapsed small cell lung cancer
Presenter: Hajime Oi
Session: Poster display session
Resources:
Abstract
512P - A phase I and extension study of S-1 and carboplatin for previously untreated patients aged 75 years or more with advanced non-small cell lung cancer
Presenter: Hisao Imai
Session: Poster display session
Resources:
Abstract
497P - Real-word efficacy of osimertinib in patients with metastatic EGFRm NSCLC: An interim analysis from a multi-center study in China
Presenter: Xiangyun Ye
Session: Poster display session
Resources:
Abstract
507P - Immune checkpoint inhibitors for patients acquired resistance to tyrosine kinase inhibitors with EGFR mutated non-small cell lung cancer: A multicenter retrospective study
Presenter: Takeshi Uenami
Session: Poster display session
Resources:
Abstract
516P - Clinical outcomes in elderly patients with advanced non-small cell lung cancer: A prospective multicenter study of the National Hospital Organization in Japan
Presenter: Masahiro Shimada
Session: Poster display session
Resources:
Abstract
486P - Phase II study of low-dose afatinib maintenance treatment for patients with EGFR-mutated non-small cell lung cancer (NJLCG1601)
Presenter: Mami Morita
Session: Poster display session
Resources:
Abstract
515P - Polypharmacy as a prognostic factor in elderly patients with advanced non-small cell lung cancer treated with immune checkpoint inhibitors
Presenter: Taiki Hakozaki
Session: Poster display session
Resources:
Abstract
518P - Real world prospective clinical impact of finding actionable genomic alterations by plasma cell-free DNA next generation sequencing in advanced non-small cell lung cancer
Presenter: Beung chul Ahn
Session: Poster display session
Resources:
Abstract