Journal Thoracic Oncology

Abstracts Journal of Thoracic Oncology • Volume 12 Issue S1 January 2017
Primary endpoint of this study is the concordance of EGFR mutation status
between tissue and plasma at baseline. Secondary endpoints are overall
response rate, progression-free survival and safety. This is the first report
on the primary endpoint and early remission rate based on mutated cf-DNA.
This study was registered at UMIN (ID: 000015847). Results: Fifty-seven
patients were registered and samples from 55 patients were analyzed. Clinical
characteristics were as follows; median age: 69 years, male / female: 25/30,
PS 0/1: 23/32, c-stage III / IV / post-operative relapse: 2/37/16, exon 19 deletion
/ exon 21 L858R: 28/27. Sensitivity of plasma sample was 63.6% among
overall, while that was 84.6% in patients with distant metastasis. Eighty-two
percent of plasma positive patients at baseline showed molecular response in
plasma after two weeks of afatinib treatment. De novo T790M mutation was
detected in one patient (2%) from plasma samples. Conclusion: Liquid biopsy
seemed to be suitable especially in patients with distant metastasis. Early
molecular remission (within two weeks) was observed in 70% of patients.
Keywords: liquid biopsy, afatinib, digital PCR, Prospective study
Tao Jiang, Shengxiang Ren, Caicun Zhou
Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University
School of Medicine, Shanghai/China
Background: This study aimed to investigate the clinical value of bevacizumab
in EGFR mutant non-small cell lung cancer (NSCLC) patients who had
developed acquired resistance to EGFR-TKIs therapy that manifested as
malignant pleural effusion (MPE). Methods: A total of 86 patients were
included. Among them, 47 patients received bevacizumab plus continued
EGFR-TKIs (B+T) and 39 patients received bevacizumab plus switched
chemotherapy (B+C). Results: The curative efficacy rate for MPE in B+T group
was significantly higher than that in B+C group (89.4% vs. 64.1%, P = 0.005).
Patients in B+T group had longer progression-free survival (PFS) than those in
B+C group (6.3 vs. 4.8 months, P = 0.042). While patients with acquired T790M
mutation in B+T group had a significantly longer PFS than those in B+C group
(6.9 vs. 4.6 months, P = 0.022), patients with negative T790M had similar
PFS (6.1 vs. 5.5 months, P = 0.588). Overall survival (OS) was similar between
two groups (P = 0.480). In multivariate analysis, curative efficacy was the
independent prognostic factor for these patients (HR 0.275, P = 0.047).
POSTER SESSION 3 – P3.02B: ADVANCED NSCLC & CHEMOTHERAPY/TARGETED THERAPY/
IMMUNOTHERAPY
EGFR CLINICAL –
WEDNESDAY, DECEMBER 7, 2016
P3.02B-074 BRAIN RADIOTHERAPY WITH EGFR-TKI PLAYS AN
IMPORTANT ROLE IN 181 EGFR MUTANT NON-SMALL CELL LUNG
CANCER PATIENTS WITH BRAIN METASTASIS
Wenxian Wang 1 , Ying Jin 2
1 Chemotherapy, Zhejiang Cancer Hospital, Zhejiang/China, 2 Zhejiang Cancer
Hospital, Hangzhou/China
Background: To perform a retrospective analysis of patients with epidermal
growth factor receptor (EGFR)-mutant NSCLC patients who developed
brain metastases (BM) to assess the appropriate use of EGFR tyrosine
kinase inhibitors (TKIs), and radiation therapy (RT) for symptomatic and
asymptomatic BM. Methods: There were 482 patients diagnosed with EGFR
mutant NSCLC between June 2006 and December 2015 at Zhejiang Cancer
Hospital. Treatment outcomes had been retrospectively evaluated in 181
patients with 132 asymptomatic BM and 49 symptomatic BM. 39 patients
received first-line brain RT, 23 patients received delayed brain RT, and 34
patients did not receive brain RT. In all 49 symptomatic BM patients received
radiotherapy, except 4 patients were refusal of treatment. There were 45
patients had brain radiotherapy, 39 received WBRT and 6 were SRS. Among
132 asymptomatic brain metastasis patients, 74 received radiotherapy (63
WBRT and 11 SRS). The BM of 26 patients had still stable by the follow-up
time. 22 patients did not get information about brain RT after intracranial
progression and until the last follow-up. 10 patients were refusal of brain RT
treatment. Results: In 49 symptomatic BM patients, 45 received RT including
40 WBRT and 5 SRS. Among 6 SRS. The iPFS for patients treated with SRS
and WBRT was 12.4 months and 9.5 months (P=0.895). Median OS in the SRS
group was also greater than in those treated with WBRT (37.7 vs 21.1 months)
(P=0.194). In the group of 132 asymptomatic BM patients, There were 86
patients who had not received brain radiotherapy before TKI and 46 received
RT whether upfront or concurrent TKI. The median OS in the upfront RT
group was also longer than in the upfront TKI (24.9 vs 17.4 months)(P=0.035).
Further analysis with subgroup to the timing of using radiotherapy, among
the 74 patients, 33 underwent concurrent TKI and radiation therapy, 13 were
given TKI after failure of first-line radiotherapy plus chemotherapy and 28
patients received radiotherapy after TKI. The iPFS of three groups was 11.1
months, 11.3 months and 8.1 months (P=0.032). The mOS of three groups was
21.9 months, 26.2 months and 17.1 months(P=0.085). Conclusion: The study
suggests that the deferral of brain RT may result in inferior OS in NSCLC
patients harboring EGFR mutations and asymptomatic BM. For now, the
standard-of-care treatment for newly diagnosed BM whether symptomatic
or asymptomatic brain metastases should remain upfront RT followed by
EGFR-TKI therapy. First-line brain RT may improve long-term survival in EGFR
mutation patients.
(See figures next page)
Keywords: Brain metastases, EGFR TKI, non-small cell lung cancer,
radiotherapy
POSTER SESSION 3 – P3.02B: ADVANCED NSCLC & CHEMOTHERAPY/TARGETED THERAPY/
IMMUNOTHERAPY
EGFR CLINICAL –
WEDNESDAY, DECEMBER 7, 2016
P3.02B-075 ADDITION OF BEVACIZUMAB FOR MALIGNANT
PLEURAL EFFUSION AS THE MANIFESTATION OF ACQUIRED EGFR-
TKI RESISTANCE IN NSCLC PATIENTS
S648 Journal of Thoracic Oncology • Volume 12 Issue S1 January 2017