BackgroundEGFR exon 20 insertions (EGFR ex20ins) constitute a heterogeneous subset of EGFR-activating alterations. However, the effectiveness of standard therapy in patients with EGFR ex20ins remains poor.MethodsIn our study, we retrospectively collected next-generation sequencing (NGS) data from 7,831 Chinese NSCLC patients and analyzed the relationship between EGFR ex20ins variations and medical records.ResultsOur data showed that EGFR ex20ins account for up to 3.5% of all EGFR mutation non-small-cell lung cancer (NSCLC) patients and 1.6% of all NSCLC patients in China. Thirty-eight different variants of EGFR ex20ins were identified in 129 NSCLC patients. We observed that the patients with EGFR ex20ins may benefit from the anti-angiogenesis agents significantly (P = 0.027). In the EGFR ex20ins near-loop group, patients who received second-/third-generation EGFR-TKI therapy treatment as first-line treatment had a longer median progression-free survival (PFS) than those who initiated treatment with first-generation EGFR-TKI or chemotherapy. Patients with co-mutations of EGFR ex20ins near-loop and TP53 tended to have a shorter OS in second-/third-generation EGFR-TKI therapy (P = 0.039). Additionally, median PFS was significantly longer in patients harboring EGFR ex20ins far-loop variants who received chemotherapy as a first-line setting (P = 0.037).ConclusionsOverall survival was significantly longer in EGFR ex20ins patients with anti-angiogenesis agents. For the choice of first-line strategy, NSCLC with EGFR ex20ins near-loop variants may benefit from second-/third-generation EGFR-TKI, while patients harboring EGFR ex20ins far-loop variants might have better outcomes from chemotherapy. TP53 could serve as a potential predictive marker in poor prognosis for EGFR ex20ins near-loop patients.

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is an aggressive variant of inflammatory myofibroblastic tumor (IMT) and has a poor prognosis. EIMS is characterized by epithelioid morphology, neutrophilic infiltrate and specific fusion partners of anaplastic lymphoma kinase (ALK). Despite no standard therapy for EIMS, ALK tyrosine kinase inhibitors (TKIs) are recommended for these tumors. The present case describes an abdominal mass that presented in a 31-year-old male. The patient suffered from recurrence and multiple metastases 2 months after surgery. Ensartinib was administered and RANBP2-ALK fusion was detected. A partial response has been observed for 4 months and there has been no recurrence. This study provided a successful case with sustained response of targeted therapy.

e21099 Background: Liver metastasis is one of the most reasons for the poor prognosis of patients with advanced lung cancer. Seeking for active and effective treatment measures is very important for these patients. At present, the first-line standard treatment of the advanced NSCLC with EGFR mutation is EGFR-TKIs monotherapy. However, its efficacy is poor in the advanced non-small cell lung cancer with EGFR mutation and liver metastases. The objective of this study is to evaluate the efficacy of EGFR-TKIs plus chemotherapy in patients with EGFR mutation of advanced non-small cell lung cancer with liver metastases. Methods: The clinical data of a total of 384 advanced NSCLC patients with EGFR mutation positive who were admitted to The Affiliated Cancer Hospital of Zhengzhou University/Henan Cancer Hospital from February 2017 to June 2020 were retrospectively analyzed. There were 75 patients with liver metastases. Patients were divided into two groups, and accepted EGFR-TKIs monotherapy or EGFR-TKIs plus chemotherapy, respectively. All patients treatment response were evaluated by the RECIST1.1 Response evaluation criteria in solid tumors.Progression free-survival (PFS) were also analyzed. Results: In the study, 75 patients were finally screened. There were 37 patients in the EGFR-TKIs monotherapy group and 38 patients in the TKI plus chemotherapy group. The median follow-up time was 23.0 months. At the latest follow-up date (2021-01-01), 57 patients had disease progression and 35 patients had died. Comparing with EGFR-TKIs monotherapy,the first-line PFS of EGFR-TKI plus chemotherapy group was longer, and the median PFS was 12.7 months VS 7.4 months (P = 0.018).The ORR of primary lung lesions was no significant difference between these two groups（65.8%VS 51.4% P = 0.204), and DCR (97.4% VS 94.6% P = 0.981) also had no difference between two groups（P > 0.05）. ORR of liver metastases in the EGFR-TKIs plus chemotherapy group was significantly higher than EGFR-TKIs monotherapy group ORR (65.8%VS 40.5%，P = 0.028). Conclusions: In advanced NSCLC patients with EGFR mutation and liver metastases, comparing with EGFR-TKIs monotherapy, taking EGFR-TKIs plus chemotherapy as first-line treatment had longer PFS, and better efficacy on liver lesions.