Pembrolizumab Versus High-Dose Interferon-α2b as Adjuvant Therapy for Pediatric Melanoma: A Retrospective Study.

INTRODUCTION: Pembrolizumab is well-tolerated in pediatric patients with advanced tumors, consistent with results in adults. However, information on the safety and efficacy of adjuvant pembrolizumab in children and adolescents with melanoma is lacking. OBJECTIVES: To compare pembrolizumab versus high-dose interferon-α2b (HDI) as adjuvant therapy in pediatric patients with melanoma. METHODS: We performed a retrospective study of pediatric patients diagnosed with melanoma between January 2008 and April 2022. Relapse-free survival (RFS) and the 1-year RFS rate were compared between patients receiving adjuvant pembrolizumab or HDI. RESULTS: Seventy-five pediatric patients with melanoma were screened from a database of 6,013 patients. Twenty-four patients were finally enrolled, of whom 9 received pembrolizumab and 15 received HDI as adjuvant therapy. By August 31, 2022, the median follow-up times were 23.6 months and 98.7 months in the pembrolizumab and HDI groups, respectively. There was no significant difference in median RFS between two groups (not reached versus 38.7 months, P = 0.11). The median overall survival was not reached in either group. The 1-year RFS rates were 88.9% and 66.7% in the pembrolizumab and HDI groups, respectively. All adverse events in the pembrolizumab group were grade 1 or 2, but grade 3-5 adverse events occurred in two (13%) patients receiving HDI. CONCLUSIONS: RFS was similar in pediatric patients with melanoma receiving adjuvant pembrolizumab or HDI, but pembrolizumab was associated with a reduced risk of recurrence and a more favorable safety profile. However, due to the small sample size and differences in follow-up time, larger and prospective studies are still warranted to explore better adjuvant therapies for pediatric melanoma.

Association Between RET Fusions and Efficacy of Pemetrexed-based Chemotherapy for Patients With Advanced NSCLC in China: A Multicenter Retrospective Study.

BACKGROUND: Rearranged during transfection (RET) proto-oncogene gene fusions are rare in non-small-cell lung cancer (NSCLC). We compared the efficacy of pemetrexed-based chemotherapy with other chemotherapy regimens in patients with NSCLC with different RET fusion subtypes. PATIENTS AND METHODS: A retrospective, multicenter study of patients with pathologically confirmed stage IIIB/IV lung adenocarcinomas was conducted. RET rearrangements were detected using next generation sequencing. We analyzed the clinical characteristics of patients with RET-rearranged NSCLC and the efficacy of chemotherapy regimens. We also evaluated the efficacy between groups of patients with and without KIF5B-RET-rearranged lung cancer. RESULTS: We evaluated 62 patients with NSCLC and RET rearrangements, including 41 with KIF5B-RET, 15 with CCDC6-RET, and 6 with other rare fusion subtypes. Of these 62 patients, 50 had stage IIIB/IV. We also evaluated 40 patients with first-line chemotherapy information available. The median progression-free survival was significantly different between those receiving pemetrexed-based chemotherapy and those receiving other chemotherapy regimens (9.2 vs. 5.2 months; P = .007). The median progression-free survival for patients with KIF5B-RET fusion and non-KIF5B-RET fusion was not significantly different statistically (7.8 vs. 11.2 months; P = .847). For second-line chemotherapy, a statistically significant difference was found between the chemotherapy regimens (4.9 vs. 2.8 months; P = .049). Survival follow-up data were available for 38 patients with advanced NSCLC. The median overall survival was 26.4 months. The overall survival of the patients with RET-rearranged NSCLC who had received pemetrexed-based chemotherapy versus no pemetrexed-based chemotherapy was 35.2 versus 22.6 months (P = .052). No difference in survival was observed between the patients with KIF5B-RET and non-KIF5B-RET rearrangements. CONCLUSIONS: Pemetrexed-based treatment should be considered first when selecting the chemotherapy regimen for patients with NSCLC and RET rearrangements.

A Real-World Study in Advanced Non-Small Cell Lung Cancer with KRAS Mutations.

BACKGROUND: KRAS gene mutations are well known as a key driver of advanced non-small cell lung cancer (NSCLC). The impact of KRAS-mutant subtypes on the survival benefit from salvage chemotherapy is controversial. Here, we present a real-world study in patients across China with advanced NSCLC with KRAS mutations using a website-based patient self-report system. METHODS: We identified a total of 75 patients diagnosed with KRAS-mutant (determined by molecular sequencing) advanced NSCLC between 2014/5/9 and 2019/5/30. KRAS mutation subtypes were divided into G12C and non-G12C groups for statistical analysis. The clinicopathological characteristics and treatment survival benefit in all patients with a KRAS mutation were evaluated. Programmed death-ligand 1 (PD-L1) expression data were collected from 30 patients in the same cohort. RESULTS: In this study, 23 patients with stage IIIB NSCLC and 52 patients with stage IV NSCLC were enrolled with 58 men and 17 women; the median age was 60 years (39-84). All patients received regular chemotherapy/radiotherapy/targeted therapy/immune therapy as per the disease condition. Four main KRAS mutation subtypes were detected: G12C (33%), G12V (19%), G12A (12%), and G12D (12%). Three predominant KRAS comutations were detected: TP53-KRAS (31%), EGFR-KRAS (11%), and STK11-KRAS (8%). Compared with the KRAS non-G12C mutation subtype, patients with the KRAS G12C mutation had potentially longer progression-free survival (PFS) after first-line chemotherapy (4.7 vs. 2.5 months, p < 0.05). Pemetrexed-based chemotherapy appeared to be superior to taxanes- and gemcitabine-based chemotherapies in all patients (PFS: 5.0 vs. 1.5 and 2.3 months, respectively, p > 0.05). Cox regression analysis showed that the KRAS G12C mutation and pemetrexed-based first-line chemotherapy were positive influencers for PFS after first-line (hazard ratios = 0.31 and 0.55, respectively, P < 0.05), but not second-line chemotherapies. CONCLUSION: The KRAS G12C mutation could be a predictive biomarker for better survival benefit from first-line chemotherapy in patients with advanced NSCLC and KRAS mutations. The first-line chemotherapy regimen could possibly influence the outcome in patients with KRAS mutations. Larger and prospective clinical trials are warranted to confirm our conclusions.