Rechallenge with Anti-EGFR Treatment in RAS/BRAF wt Metastatic Colorectal Cancer (mCRC) in Real Clinical Practice: Experience of the GITuD Group.

BACKGROUND: There are few third- and fourth-line therapeutic options for metastatic colorectal cancer (mCRC). In RAS/BRAF wild-type (wt) mCRC previously treated with anti-epidermal growth factor receptor (anti-EGFR) (first-line) and relapsed after a good response, retreatment with anti-EGFR (rechallenge) emerges as a therapeutic alternative. OBJECTIVE: The aim was to show the activity and safety of anti-EGFR rechallenge in RAS/BRAF wt mCRC in real-world practice. PATIENTS AND METHODS: A multicenter, retrospective, observational study (six hospitals of the Galician Group of Research in Digestive Tumors) was conducted. Adult patients with RAS/BRAF wt mCRC, evaluated by liquid biopsy, were included. They received anti-EGFR rechallenge (cetuximab, panitumumab) as monotherapy, or combined with chemotherapy, in third- or subsequent lines. Efficacy (overall response rate [ORR], disease control rate [DCR], overall survival [OS], and progression-free survival [PFS]) and safety (incidence of adverse events [AEs]) were assessed. RESULTS: Thirty-one patients were analyzed. Rechallenge (median 6 cycles [range 1-27], mainly cetuximab [80.7%]), started at a median anti-EGFR-free time of 18.4 months (1.7-37.5 months) after two (38.7%) or more (61.3%) lines of treatment; 64.5% of patients received a full dose. Median OS and PFS were 9.8 months (95% confidence interval [CI] 8.2-11.4) and 2.6 months (95% CI 1.7-3.4), respectively. ORR was 10%, and DCR was 30%. The most common AEs were diarrhea (35.5%), anemia (29%), emesis (6.4%), and neutropenia (6.4%); < 5% grade ≥ 3; 48.4% of patients reported anti-EGFR-related skin toxicity (grade > 1). Hypomagnesemia required supplements in 29% of patients. Dose delays (≥ 3 days) and reduction (≥ 20%) were reported in 11 (35.5%) and seven patients (22.6%), respectively. CONCLUSIONS: In RAS/BRAF wt mCRC patients, an anti-EGFR rechallenge provides a feasible therapeutic option with clinical benefit (survival) and a manageable safety profile.

EGFR-mutated advanced lung cancer. Data from a single institution, the Hospital of Leon, in Spain.

INTRODUCTION: 10-16% of non-small cell lung cancer (NSCLC) cases have the epidermal growth factor receptor (EGFR) amplified and/or mutated. Studies show that EGFR tyrosine kinase inhibitors (TKIs) significantly prolong progression-free survival (PFS) in patients with advanced NSCLC compared to those treated with platinum-based chemotherapy (CT) doublets. Our aim is to perform a real-world survival analysis of patients treated with TKI as first-line therapy at the Hospital of Leon (CAULE) in Spain. The impact on global survival rates and responses to clinical and histopathological factors were also analyzed. MATERIAL AND METHODS: We retrospectively reviewed patients diagnosed with EGFR-mutated NSCLC who received treatment with EGFR-TKI in the Department of Oncology at the University of Leon Health Center complex between March 2011 and June 2018. Data was analyzed with Kaplan-Meier and Cox regression models to show overall survival (OS), progression-free survival (PFS), and the associated variables. RESULTS: 53 patients were included in the study, 50% (n = 27) were treated with gefitinib, 32% (n = 18) with erlotinib and 10% (n = 6) with afatinib. The median OS and PFS were 27.7 months (95% CI: 21-33.8 months) and 18 months (95% CI 14.25-21.89 months), respectively. The variables associated with OS and with PFS were exon19 deletion as a protective factor and presence of extrathoracic metastasis as a risk factor. The most frequent adverse effects were rash, diarrhea, asthenia, and conjunctivitis. CONCLUSIONS: Real-world analysis of this data confirms that treatment with TKI is beneficial for patients diagnosed with EGFR-mutated NSCLC. Our OS outcomes were similar to those reported in clinical trials.

Relationship between Aldehyde Dehydrogenase, PD-L1 and Tumor-Infiltrating Lymphocytes with Pathologic Response and Survival in Breast Cancer.

Aldehyde dehydrogenase 1A1 (ALDH1A1) is a cancer stem cell (CSC) marker related to clinical outcomes in breast cancer (BC). The aim of this study was to analyze the relationship between ALDH1A1, programmed death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) in triple negative (TN) and human epidermal growth factor receptor 2-positive (HER2+) BC tumors, and its association with clinicopathological characteristics and outcomes. A retrospective, historical cohort study of patients diagnosed with early or locally advanced BC treated with neoadjuvant chemotherapy was conducted. ALDH1A1, PD-L1 expression and TILs were assessed using immunohistochemistry. A total of 75 patients were analyzed (42.7% TN, 57.3% HER2+ tumors). ALDH1A1+ was related to HTILs (p = 0.005) and PD-L1+ tumors (p = 0.004). ALDH1A1+ tumors presented higher CD3+ (p = 0.008), CD4+ (p = 0.005), CD8+ (p = 0.003) and CD20+ (p = 0.006) TILs. ALDH1A1+ (p = 0.018), PD-L1+ (p = 0.004) and HTILs (p < 0.001) were related to smaller tumors. ALDH1A1+ was related to pathologic complete response (pCR) (p = 0.048). At the end of the follow-up (54.4 [38.3−87.6] months), 47 patients (62.7%) remained disease-free, and 20 (26.7%) had died. HTILs were related to improved disease-free survival (p = 0.027). ALDH1A1+ was related to PD-L1+ and HITLs, that might be related to higher pCR rates with neoadjuvant therapy.