Virtual Library
Start Your Search
S. Leedy
Author of
-
+
P2.02 - Biology/Pathology (ID 616)
- Event: WCLC 2017
- Type: Poster Session with Presenters Present
- Track: Biology/Pathology
- Presentations: 1
- Moderators:
- Coordinates: 10/17/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)
-
+
P2.02-011 - Clinical and Molecular Features of Lung Cancers with Increased FGFR1 mRNA and/or Gene Copy Number (ID 8825)
09:30 - 09:30 | Author(s): S. Leedy
- Abstract
Background:
Lung cancer cell line data suggest FGFR1 status defined by FGFR1 mRNA levels and FGFR1 gene copy number can predict sensitivity to FGFR tyrosine kinase inhibitors (TKIs).
Method:
A phase II biomarker preselected trial of ponatinib, an FGFR1, FGFR2, and FGFR4 targeted TKI was designed. Patients with metastatic EGFR- and ALK-negative lung cancers (both NSCLC and SCLC) were pre-screened for FGFR1 mRNA levels by in-situ hybridization (ISH) and FGFR1 gene copy number by silver in-situ hybridization (SISH). Positivity criteria for ISH were defined as a score of 3 (Dot clusters seen in 1 to <10% tumor cells; otherwise >10 dots/cell in ≥ 10% tumor cells), or 4 (Dot clusters seen in ≥ 10% of tumor cells). Positivity for SISH was defined as an average of ≥ 4 FGFR1 signal clusters/nucleus or FGFR1/CEN8 ratio ≥ 2.0. Clinical factors including sex, histology, age and sites of metastases at diagnosis of stage IV disease, smoking status, status of other known molecular drivers, and response to initial platinum-doublet therapy for stage IV disease were collected.
Result:
From 11/2013 to 05/2017, the study has pre-screened 163 patient samples for FGFR1 ISH and SISH. Thirty-eight (23.3%) had insufficient tissue; four had incomplete clinical or FGFR1 information. Clinical variables according to FGFR1 ISH/SISH status (n=121) are summarized in Table 1. Impact of alternate positivity cut-points, outcomes of patients treated with ponatinib and survival analysis according to ISH/SISH subgroups will be presented. Figure 1
Conclusion:
Although the numbers were small, the FGFR1 ISH+/SISH+ subgroup had a greater percentage small cell histology, liver metastases at diagnosis and male sex compared to other FGFR1 subgroups. FGFR1 ISH and/or SISH positivity can overlap with other known oncogenic drivers suggesting that the initial cut-points for FGFR1 positivity used may be too low to identify a true FGFR1 addicted state.
