Abstract 4526
Background
Imatinib mesylate is approved in unresectable tumors and has been also proposed in the neoadjuvant setting in order to reduce tumor size and post-operative relapses for difficult to resect DFSP. The aim of this study was to evaluate the long-term results of neoadjuvant imatinib and other TKI used in DFSP.
Methods
The files of all patients with the following criteria seen from 2007 to 2017 in our center were collected in this retrospective study: a/histologically proven primary or recurrent DFSP with COL1A1-PDGFB translocation b/ difficult to treat but surgically manageable as assessed in pluridisciplinary tumor board, c/received first-line neoadjuvant TKI (imatinib, pazopanib). The primary endpoint was long-term progression-free survival (PFS).
Results
27 patients (median 42 years, range: 18-63) were included, of whom 9 (33%) had fibrosarcomatous transformation on pre-TKI biopsy. 10 patients had primary tumors and 17 presented recurrences. Median tumor size was 6 cm (range 3-30). 24 patients received imatinib (median dose= 600mg/day), 3 received pazopanib (median dose= 600mg/day) for a median of 7 months. The best MRI response to ITK treatment before surgery according to RECIST1.1 consisted of complete/partial response (33%) or stability (48%). DFSP was surgically removed in 24 patients (89%) after a median of 7 months and 2 surgeries. Two patients (7%) did not receive surgery because of metastasis progression. One other patient declined surgery. 23 of 24 patients surgically treated were disease-free after 50 months of median follow-up (range 10-133). One patient developed distant metastasis 37 months after the complete surgical resection. The median PFS was 44 months (range 10-133).The histological response localization was mainly patchy (n = 10) or diffuse (n = 7). The median percentage of therapeutic response surface was 65%.Treatment-related adverse events occurred in 23 patients (85%). 4 patients had grade 3 or higher toxicities (2 grade 3 and 4 neutropenia, 1 grade 3 cholestasis, 1 grade 3 nausea) requiring temporary treatment disruption and dose reductions.
Conclusions
TKI are effective neoadjuvant treatment for locally advanced or inoperable DFSP with long-term PFS and few severe adverse events.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4325 - Multiple synchronous mechanisms may contribute to osimertinib resistance in non-small cell lung cancer (NSCLC) patients: insights of the MATCH-R study
Presenter: Diego Enrico
Session: Poster Display session 1
Resources:
Abstract
2185 - Sequential treatment with afatinib followed by 3rd generation EGFR-TKI – subgroup analysis of the GIDEON trial: a prospective non-interventional study (NIS) in EGFR mutated NSCLC patients in Germany
Presenter: Wolfgang Brückl
Session: Poster Display session 1
Resources:
Abstract
1524 - Effectiveness of sequencing TKIs in patients with EGFR mutation-positive Non-small-Cell Lung Cancer (NSCLC): A French National medico administrative claim database analysis
Presenter: Nicolas Girard
Session: Poster Display session 1
Resources:
Abstract
5733 - Phase II study of osimertinib in NSCLC patients with EGFR exon 20 insertion mutation: A multicenter trial of the Korean Cancer Study Group (LU17-19)
Presenter: Tae Min Kim
Session: Poster Display session 1
Resources:
Abstract
5440 - Different stories for different EGFR exon 19 deletion variants
Presenter: Chao Zhao
Session: Poster Display session 1
Resources:
Abstract
2982 - Safety and activity of alflutinib in patients with advanced EGFR T790M mutation non-small cell lung cancer who progressed after EGFR-TKI therapy
Presenter: Yuan-Kai Shi
Session: Poster Display session 1
Resources:
Abstract
4002 - Afatinib followed by osimertinib in patients with EGFR mutation-positive (EGFRm+) advanced NSCLC: updated data from the GioTag real-world study
Presenter: Maximilian Hochmair
Session: Poster Display session 1
Resources:
Abstract
2941 - Treatment patterns of EGFR mt+ NSCLC IV pts: Real world data of the NOWEL network
Presenter: Julia Roeper
Session: Poster Display session 1
Resources:
Abstract
4154 - TP53 mutations predicts worse prognosis in EGFR-mutated NSCLC patients receiving TKIs in first- or further line of treatment
Presenter: Matteo Canale
Session: Poster Display session 1
Resources:
Abstract
1175 - HER3 ligand heregulin expression and clinical implication in patients with epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer treated with EGFR-tyrosine kinase inhibitors
Presenter: Kimio Yonesaka
Session: Poster Display session 1
Resources:
Abstract