Purpose: In hormone receptor-positive, human epidermal growth factor receptor 2–negative metastatic breast cancer (HR+ HER2–MBC), the mainstay treatment options include cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) and everolimus (EVE) in combination with endocrine treatment. This study aims to compare the outcomes of the following treatment sequences: CDK4/6i followed by EVE and EVE followed by CDK4/6i. Materials and Methods: Data from HR+ HER2– MBC patients treated between January 2014 and November 2020 with both CDK4/6i and EVE were retrospectively analyzed. Results: Among the 88 patients included in the study, 51 received CDK4/6i before EVE (C→E group), and 37 received EVE before CDK4/6i (E→C group) with endocrine treatment. More patients in the E→C group had endocrine resistance (13.7% vs. 40.5%), experienced palliative chemotherapy (7.8% vs. 40.5%), and were heavily treated (treated as ≥ 3rd line, 5.9% vs. 40.5%). Median overall survival was 46.8 months in the C→E group and 38.9 months in the E→C group (p=0.151). Median composite progression-free survival (PFS), defined as the time from the start of the preceding regimen to disease progression on the following regimen or death, was 24.8 months in the C→E group vs. 21.8 months in the E→C group (p=0.681). Median PFS2/PFS1 ratio did not differ significantly between groups (0.5 in the C→E group, 0.6 in the E→C group; p=0.775). Ten patients (11.4%) discontinued EVE, and two patients (2.3%) discontinued CDK4/6i during treatment. Conclusion Although the CDK4/6i-based regimen should be considered as an earlier line of treatment, CDK4/6i- and EVE-based treatments can be valid options in circumstances where the other treatment had been already given.

Purpose: This study aimed to investigate the clinical outcomes with gemcitabine-carboplatin (GCb), the standard treatment for patients with advanced urothelial carcinoma (UC) who are ineligible for cisplatin-based regimens, in advanced UC patients with a glomerular filtration rate (GFR) < 30 mL/min. Materials and Methods: A retrospective cohort study involving GCb-treated advanced UC patients with GFR < 60 mL/min (n=89) was performed. Clinical outcomes were compared between subgroups with GFR < 30 mL/min and GFR ≥ 30 mL/min but < 60 mL/min. Results: Most baseline characteristics were comparable between the two subgroups. Patients with GFR < 30 mL/min had a significantly lower objective response rate (12.5%) compared to those with higher GFR levels (56.7%) (p=0.004). The number of GCb cycles was significantly lower in patients with GFR < 30 mL/min (median 2 cycles) than in those with higher GFR levels (median 6 cycles) (p=0.002). Compared to those with GFR ≥ 30 mL/min but < 60 mL/min, patients with GFR < 30 mL/min showed significantly worse progression-free survival (PFS) and overall survival (OS) (p < 0.001 for both). Further stratification of patient subgroups according to their GFR (i.e., GFR ≥ 45 mL/min but < 60 mL/min vs. GFR ≥ 30 mL/min but < 45 mL/min vs. GFR < 30 mL/min) revealed significantly different PFS and OS (p < 0.001 for both). Conclusion The use of GCb is discouraged in advanced UC patients with GFR < 30 mL/min. Alternative therapeutic approaches with better efficacy are warranted for these patients.

Purpose: This study aims to evaluate the prognosis of pathologically node-positive bladder cancer after neoadjuvant chemotherapy, the role of adjuvant chemotherapy in these patients, and the value of preoperative clinical evaluation for lymph node metastases. Materials and Methods: Patients who received neoadjuvant chemotherapy followed by partial/radical cystectomy and had pathologically confirmed lymph node metastases between January 2007 and December 2019 were identified and analyzed. Results: A total of 53 patients were included in the study. The median age was 61 years (range, 34 to 81 years) with males comprising 86.8%. Among the 52 patients with post-neoadjuvant/pre-operative computed tomography results, only 33 patients (63.5%) were considered positive for lymph node metastasis. Sixteen patients (30.2%) received adjuvant chemotherapy (AC group), and 37 patients did not (no AC group). With the median follow-up duration of 67.7 months, the median recurrence-free survival (RFS) and the median overall survival (OS) was 8.5 months and 16.2 months, respectively. The 2-year RFS and OS rates were 23.3% and 34.6%, respectively. RFS and OS did not differ between the AC group and no AC group (median RFS, 8.8 months vs. 6.8 months, p=0.772; median OS, 16.1 months vs. 16.3 months, p=0.479). Thirty-eight patients (71.7%) experienced recurrence. Distant metastases were the dominant pattern of failure in both the AC group (91.7%) and no AC group (76.9%). Conclusion Patients with lymph node-positive disease after neoadjuvant chemotherapy followed by surgery showed high recurrence rates with limited survival outcomes. Little benefit was observed with the addition of adjuvant chemotherapy.

Purpose: Exon 20 insertion mutations (E20ins) in epidermal growth factor receptor (EGFR) or human epidermal growth factor receptor 2 (HER2) in non–small cell lung cancer (NSCLC) patients has become more important with emergence of novel agents targeting E20ins. Materials and Methods: Advanced/Metastatic NSCLC patients with E20ins were included. EGFR E20ins was identified by two methods, next-generation sequencing (NGS) or real-time polymerase chain reaction (PCR), while HER2 E20ins was done by NGS only. Results: Between December 2013 and July 2021, E20ins were identified in 107 patients at Asan Medical Center; 67 EGFR E20ins and 40 HER2 E20ins. Out of 32 patients with EGFR E20ins who had tested both PCR and NGS, 17 were identified only through NGS and the other 15 through both tests, giving a discordance rate of 53.1%. There was no clinically significant difference in clinicopathologic features between EGFR and HER2 E20ins; both were observed more frequently in adenocarcinoma, female and never-smokers. Brain metastases were evident at diagnosis in 31.8% of EGFR E20ins and 27.5% of HER2 E20ins, respectively. Platinum-based doublets demonstrated objective response rates (ORR) of 13.3% with a median progression-free survival (PFS) of 4.2 months for EGFR E20ins and 35.3% with 4.7 months for HER2 E20ins, respectively. In contrast, novel EGFR E20ins-targeted agents exhibited an ORR of 46.2% with a median PFS of 5.4 months, while HER2-targeted agents showed an ORR of 50% with that of 7.0 months. Conclusion Identification of EGFR and HER2 E20ins is more important as their targeted therapies improved outcomes. Upfront NGS test as a comprehensive molecular approach is strongly warranted.