Abstract 1923P
Background
Although differentiated thyroid cancer (DTC) patients (pts) have a good prognosis; 5-10% of pts become radioiodine-refractory (RR) and experience recurrence or distant metastasis. LEN was approved to treat locally recurrent or metastatic, progressive, radioactive iodine-refractory DTC. We assessed the efficacy and safety of LEN in real-life practice in pts with metastatic RR DTC consecutively treated at a single center in Russia.
Methods
Retrospective analysis of 44 pts treated with LEN >2 months from Dec 2015 to Mar 2020 according to the prescribing information of LEN and local standards of treatment. The response was determined by RECIST 1.1, adverse events were assessed using pts and clinical records.
Results
The histological types were papillary DTC (81.8%) and follicular DTC (18.2%). Median age was 65 (range 31-79) years, pts had ECOG status 0-1 (79.5%) and ECOG 2 (20.5%), and 30 (68.2%) pts had 2 or more sites of metastasis. Distant metastases were in lungs, bones, and lymph nodes (95.5%, 20.5%, and 59.1%, respectively). LEN was used as first-line therapy in 34 (77.3%) pts and as second-line after sorafenib in 10 (22.7%) pts. Median duration of treatment was 16 months (range 2-35). By the cut-off day therapy was continued in 35 (79.5%). Complete response, partial response and stable disease were observed in 1 (2.3%), 26 (59.1%) and 9 (20.5%) pts, respectively; progression (PD) was recorded in 2 (4.5%) pts and 6 (13.6%) pts were not evaluable. The most common AEs of any grade in the LEN group were generalized weakness without activity of daily living estimation (90.9%), appetite loss (75.0%), hypertension (68.2%), weight loss (65.9%), diarrhea (50.0%), nausea (31.8%), proteinuria (27.3%), stomatitis (11.4%). Nine (20.5%) pts required treatment discontinuation and reasons were due to death, PD and AE in 5 (11.4%), 2 (4.5%) and 2 (4.5%) pts, respectively. Five deaths occurred. Dose reductions to 20, 18, 14 and 10 mg were in 10 (22.7%), 3 (6.7%), 7 (15.9%) and 7 (15.9%) pts, respectively; 16 (36.4%) pts did not require dose reduction.
Conclusions
61,4 % ORR shows good efficacy of lenvatinib in population of pts with poor performance status (ECOG 1-2).
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Eisai LLC Russia.
Disclosure
All authors have declared no conflicts of interest.