Purpose: PTEN, AKT, and KRAS are epidermal growth factor receptor (EGFR) downstream regulators. KRAS mutations confer resistance to cetuximab. This retrospective study investigated the role of PTEN loss, AKT phosphorylation, and KRAS mutations on the activity of cetuximab plus irinotecan in patients with metastatic colorectal cancer (mCRC). Patients and Methods: A cohort of patients with irinotecan-refractory mCRC who were treated with cetuximab plus irinotecan was tested for PTEN immunoreactivity (ie, immunohistochemistry; IHC), pAKT IHC, and KRAS mutations. Analyses were performed both on primary tumors and on related metastases, and the association among IHC, mutational results, and treatment outcomes was investigated. Results: One-hundred two patients were eligible. Ninety-six primary tumors, 59 metastases, and 53 paired samples were available. Forty-nine primary tumors (58% of assessable samples) had a preserved PTEN expression (PTEN-positive), whereas 35 (40% of assessable samples) were pAKT-positive. Levels of concordance between primary tumors and metastases were 60%, 68%, and 95% for PTEN, pAKT, and KRAS, respectively. PTEN status on primary tumors and pAKT status both on primary tumors and on metastases did not predict response or progression-free survival (PFS). On metastases, 12 (36%) of 33 patients with PTEN-positive tumors were responders compared with one (5%) of 22 who had PTEN-negative tumors (P = .007). The median PFS of patients with PTEN-positive metastases was 4.7 months compared with 3.3 months for those with PTEN-negative metastases (hazard ratio [HR], 0.49; P = .005). Patients with PTEN-positive metastases and KRAS wild type had longer PFS compared with other patients (5.5 months v 3.8 months; HR, 0.42; P = .001). Conclusion: PTEN loss in metastases may be predictive of resistance to cetuximab plus irinotecan. The combination of PTEN IHC and KRAS mutational analyses could help to identify a subgroup of patients with mCRC who have higher chances of benefiting from EGFR inhibition.

Background: Arterial hypertension occurring during antiangiogenic therapy has been correlated with the biological inhibition of the vascular endothelial growth factor-related pathway and may represent a possible clinical marker for treatment efficacy. The aim of our study was to retrospectively assess if grades 2–3 hypertension were associated with response to bevacizumab, progression-free survival (PFS) and survival in metastatic colorectal cancer patients treated with first-line bevacizumab. Patients and methods: Patients with histologically proven, metastatic colorectal cancer receiving bevacizumab as first-line therapy in combination with irinotecan and 5-fluorouracil were eligible for our analysis. Results: Thirty-nine metastatic colorectal cancer patients were eligible. Eight patients (20%) developed grades 2–3 hypertension. A partial remission was observed in six of eight cases with bevacizumab-related hypertension (75%) and in 10 of 31 (32%) patients with no hypertension (P = 0.04). Median PFS was 14.5 months for patients showing bevacizumab-related hypertension, while it was 3.1 months in those without hypertension (P = 0.04). Median overall survival was not reached in patients with hypertension while it was 15.1 months in the remaining cases (P = 0.11). Conclusions: Our data indicate that bevacizumab-induced hypertension may represent an interesting prognostic factor for clinical outcome in advanced colorectal cancer patients receiving first-line bevacizumab.

Purpose: We hypothesized that the detection of epidermal growth factor receptor (EGFR) expression performed in primary tumors for treatment with EGFR-targeted monoclonal antibodies could not always correlate with EGFR status in metastatic sites, thus making cancer cells in these sites resistant to therapy. The aim of our study was to correlate EGFR expression on primary tumors and related metastases in order to find out whether assessing EGFR status on primary cancer is to be considered an effective tool for planning treatment with EGFR-targeted antibodies. Patients and Methods: We retrospectively evaluated EGFR immunohistochemistry from primary tumors and related metastatic sites in 99 colorectal cancer patients. The site of primary tumor was colon in 77 patients (78%) and rectum in 22 patients (22%). Metastatic sites analyzed were liver in 84 patients (81%), lung in 13 patients (13%), bone in one patient (1%), and brain in five patients (5%). EGFR status was defined as positive if the percentage of malignant cells stained was ≥ 1%. Results: EGFR status was positive in 53 primary tumors (53%). In 19 primary tumors expressing EGFR (36%), the corresponding metastatic site was found negative, whereas it was found positive in seven metastases (15%) from EGFR-negative primary cancers. The difference between these two groups of patients (ie, EGFR-positive to EGFR-negative v EGFR-negative to EGFR-positive) was statistically significant (P = .036). Conclusion: Our results suggest that the detection of the EGFR in primary colorectal cancer could be inadequate for planning therapy with EGFR-targeted monoclonal antibodies in a considerable proportion of both EGFR-positive and -negative primary tumors (36% and 15%, respectively).

Scientific data provide the evidence that secondary K-RAS mutations do not occur during anti-epidermal growth factor receptor therapy in colorectal cancer patients. This multicenter phase II prospective study aims to investigate the activity of a retreatment with a cetuximab-based therapy. We enrolled 39 irinotecan-refractory patients who had a clinical benefit after a line of cetuximab- plus irinotecan-based therapy and then a progression of disease for which underwent a new line chemotherapy and finally, after a clear new progression of disease, were retreated with the same cetuximab- plus irinotecan-based therapy. Median number of therapeutic lines before accrual was 4. Median interval time between last cycle of first cetuximab-based therapy and first cycle of the retreatment was 6 months. Overall response rate was 53.8% with 19 partial responses (48.7%) and 2 complete responses (5.1%). Disease stabilization was obtained in 35.9% of patients and progression in four patients (10.2%). Median progression-free survival was 6.6 months. The correlation between skin toxicity during first cetuximab therapy and during cetuximab rechallenge was significant (P = 0.01). Rechallenge with the same cetuximab-based therapy may achieve a new important clinical benefit further delaying the progression of disease and improving the therapeutic options.

Lung cancer is a leading cause of cancer-related deaths worldwide. About 10–30% of patients with non-small cell lung cancer (NSCLC) harbor mutations of the EGFR gene. The Tumor Microenvironment (TME) of patients with NSCLC harboring EGFR mutations displays peculiar characteristics and may modulate the antitumor immune response. EGFR activation increases PD-L1 expression in tumor cells, inducing T cell apoptosis and immune escape. EGFR-Tyrosine Kinase Inhibitors (TKIs) strengthen MHC class I and II antigen presentation in response to IFN-γ, boost CD8+ T-cells levels and DCs, eliminate FOXP3+ Tregs, inhibit macrophage polarization into the M2 phenotype, and decrease PD-L1 expression in cancer cells. Thus, targeted therapy blocks specific signaling pathways, whereas immunotherapy stimulates the immune system to attack tumor cells evading immune surveillance. A combination of TKIs and immunotherapy may have suboptimal synergistic effects. However, data are controversial because activated EGFR signaling allows NSCLC cells to use multiple strategies to create an immunosuppressive TME, including recruitment of Tumor-Associated Macrophages and Tregs and the production of inhibitory cytokines and metabolites. Therefore, these mechanisms should be characterized and targeted by a combined pharmacological approach that also concerns disease stage, cancer-related inflammation with related systemic symptoms, and the general status of the patients to overcome the single-drug resistance development.

Ten years of sorafenib in hepatocellular carcinoma: Are there any predictive and/or prognostic markers?