Alessandra Mandolesi

Epidermal Growth Factor Receptor (EGFR) Status in Primary Colorectal Tumors Does Not Correlate With EGFR Expression in Related Metastatic Sites: Implications for Treatment With EGFR-Targeted Monoclonal Antibodies

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 > or = 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).

Nuclear factor-kB tumor expression predicts response and survival in irinotecan-refractory metastatic colorectal cancer treated with cetuximab-irinotecan therapy

PURPOSE NF-kB expression has been shown to be responsible for resistance to antineoplastic agents and it also plays a part in the activation of the epidermal growth factor receptor downstream signaling pathway in colorectal tumors. The aim of our analysis was to investigate a correlation between NF-kB expression, response rate, time to progression, and survival in advanced colorectal cancer patients receiving cetuximab and irinotecan. PATIENTS AND METHODS We analyzed retrospectively the immunoreactivity for NF-kB in irinotecan-refractory patients receiving cetuximab and irinotecan. Results Seventy-six patients were analyzed. Cetuximab and irinotecan were administered as second-line chemotherapy in 19 patients and after > or = two lines of chemotherapy in the remaining 57 patients. We observed a partial response (PR) in 16 patients for an overall response rate of 24%. Thirty-two patients (48%) experienced progressive disease; median time to progression (TTP) was 3.6 months and median overall survival was 10.3 months. NF-kB was positive in 46 patients (60%). All main clinical characteristics were well balanced between NF-kB-positive and NF-kB-negative patients. The response rate was 10% (four PRs) versus 48% (12 PRs; P = .0007) in NF-kB-positive and NF-kB-negative tumors, respectively. Median TTP in NF-kB-positive patients was 3 v 6.4 months in the remaining patients (P = .021). Median overall survival was 9.5 v 15.8 months for NF-kB-positive and NF-kB-negative patients, respectively (P = .036) CONCLUSION The difference in median TTP, overall survival, and response rate seem to confirm that NF-kB may play a crucial role in predicting the efficacy of cetuximab and irinotecan in advanced colorectal tumors.

Epidermal Growth Factor Receptor (EGFR) gene copy number (GCN) correlates with clinical activity of irinotecan-cetuximab in K-RAS wild-type colorectal cancer: a fluorescence in situ (FISH) and chromogenic in situ hybridization (CISH) analysis

BackgroundK-RAS wild type colorectal tumors show an improved response rate to anti-EGFR monoclonal antibodies. Nevertheless 70% to 40% of these patients still does not seem to benefit from this therapeutic approach. FISH EGFR GCN has been previously demonstrated to correlate with clinical outcome of colorectal cancer treated with anti-EGFR monoclonal antibodies. CISH also seemed able to provide accurate EGFR GCN information with the advantage of a simpler and reproducible technique involving immunohistochemistry and light microscopy. Based on these findings we investigated the correlation between both FISH and CISH EGFR GCN and clinical outcome in K-RAS wild-type colorectal cancer treated with irinotecan-cetuximab.MethodsPatients with advanced K-RAS wild-type, colorectal cancer receiving irinotecan-cetuximab after failure of irinotecan-based chemotherapy were eligible.A cut-off value for EGFR GCN of 2.6 and 2.12 for FISH and CISH respectively was derived from ROC curve analysis.ResultsForty-four patients were available for analysis. We observed a partial remission in 9 (60%) and 2 (9%) cases with a FISH EGFR GCN ≥ 2.6 and < 2.6 respectively (p = 0.002) and in 10 (36%) and 1 (6%) cases with a CISH EGFR GCN ≥ 2.12 and < 2.12 respectively (p = 0.03). Median TTP was 7.7 and 6.4 months in patients showing increased FISH and CISH EGFR GCN whereas it was 2.9 and 3.1 months in those with low FISH and CISH EGFR GCN (p = 0.04 and 0.02 respectively).ConclusionFISH and CISH EGFR GCN may both represent effective tools for a further patients selection in K-RAS wild-type colorectal cancer treated with cetuximab.

Insulin-like growth factor (IGF) 1 and 2 help to predict disease outcome in GIST patients

BACKGROUND The expression of the insulin-like growth factor (IGF) system has never been studied in gastrointestinal stromal tumors (GISTs). PATIENTS AND METHODS We studied the immunohistochemical expression of IGF1 receptor (IGFR-I), IGF1 and IGF2 in 94 samples of GISTs. IGF1 and IGF2 expression was scored in three classes: negative (N), moderate (M) and strong (S), according to staining intensity and extent. RESULTS IGFR-I was overexpressed in all cases. IGF1 and IGF2 expression was absent in 25 and 48 cases, moderate in 29 and 16 cases and strong in 40 and 30 cases, respectively. Strong IGF1 expression significantly correlated with higher mitotic index (P = 0.0001), larger (P = 0.01), higher risk (P = 0.0002), metastatic (P = 0.0001) and relapsed (P = 0.04) GISTs. Strong IGF2 expression correlated with higher mitotic index (P = 0.05) and higher risk GISTs (P = 0.001). The Kaplan-Meier analysis (N versus M versus S) showed a significant worsening of the disease-free survival (DFS) with the increase of IGF1 (P = 0.02) and IGF2 (P = 0.02) expression. In the subgroup of patients with operated high-risk GISTs, there was a better trend in DFS for patients affected by GISTs with negative IGF1 and IGF2. CONCLUSIONS The expression of IGF1 and IGF2 seems to predict relapse in GIST patients.

Clinical Evidence for Three Distinct Gastric Cancer Subtypes: Time for a New Approach

Background Recently, a new classification for gastric cancer (GC) has been proposed, based on Laurens histology and on anatomic tumour location, identifying three subtypes of disease: type 1 (proximal non diffuse GC), type 2 (diffuse GC) and type 3 (distal non diffuse GC). Aim of our analysis was to compare clinical outcome according to different GC subtypes (1,2,3) in metastatic GC patients receiving first-line chemotherapy. Patients and Methods Advanced GC pts treated with a first-line combination chemotherapy were included in our analysis. Pts were divided in three subgroups (type 1, type 2 and type 3) as previously defined. Results A total of 248 advanced GC pts were included: 45.2% belonged to type 2, 43.6% to type 3 and 11.2% to type 1. Patients received a fluoropyrimidine-based chemotherapy doublet or three drugs regimens including a platinum derivate and a fluoropyrimidine with the addition of an anthracycline, a taxane or mytomicin C. RR was higher in type 1 pts (RR = 46.1%) and type 3 (34,3%) compared to type 2 (20,4%), (p = 0.015). Type 2 presented a shorter PFS, median PFS = 4.2 months, compared to type 1, mPFS = 7.2 months, and type 3, mPFS = 5.9 months (p = 0.011) and also a shorter OS (p = 0.022). Conclusions Our analysis suggests that GC subtypes may be important predictors of benefit from chemotherapy in advanced GC patients. Future clinical trials should take in account these differences for a better stratification of patients.

Epidermal growth factor receptor (EGFR) gene promoter methylation and cetuximab treatment in colorectal cancer patients

Background:Epidermal growth factor receptor (EGFR) promoter methylation may be responsible for the loss of EGFR expression in neoplastic cells. The primary aim of our study was to verify a possible correlation between EGFR gene promoter methylation and clinical outcome in metastatic colorectal cancer patients receiving chemotherapy with irinotecan and cetuximab.Methods:Colorectal samples from patients treated with irinotecan–cetuximab were analysed for EGFR promoter methylation and EGFR immunohistochemistry.Results:Fifty-two patients were analysed. Thirty patients (58%) showed EGFR promoter hypermethylation. In EGFR promoter methylated and EGFR promoter unmethylated patients, we observed a partial response in 3 (10%) and 13 (59%) patients, respectively (P=0.03), progressive disease was obtained in 19 (63%) and 2 (9%) patients, respectively, with EGFR promoter methylated and EGFR promoter unmethylated tumours (P=0.0001). Median progression-free survival was 2.4 months in patients showing EGFR promoter methylated tumours and 7.4 months for those who had EGFR promoter unmethylated tumours (P<0.0001; Figure 1). Median overall survival was 6.1 months in patients showing EGFR promoter methylated tumours and 17.8 months for those who had EGFR promoter unmethylated tumours (P<0.0001; Figure 2). CONCLUSION: EGFR promoter hypermethylation, after confirmation in larger data set, may represent a valuable asset in further studies investigating EGFR as a therapeutic target in colorectal cancer.

Insulin-like growth factor 1 expression correlates with clinical outcome in K-RAS wild type colorectal cancer patients treated with cetuximab and irinotecan.

Seventy to 40% of K‐RAS wild type colorectal tumors does not seem to benefit from treatment with antiepidermal growth factor receptor (anti‐EGFR) monoclonal antibodies. Recent data suggested that in presence of IGF‐1 system, altered activation colorectal cancer cells may escape anti‐EGFR mediated cell death. The interaction between IGF‐1 expression and K‐RAS mutational analysis was tested to verify the ability of IGF‐1 to identify a subgroup of patients more likely to benefit from EGFR‐targeted antibodies treatment. IGF‐1 expression and K‐RAS mutational status was assessed in advanced colorectal cancer patients receiving irinotecan/cetuximab. One hundred twelve patients were analyzed. IGF‐1 was negative in 30 patients (27%) and overexpressed in the remaining 82 cases (73%). In IGF‐1 negative and IGF‐1 positive tumors, we observed progressive disease in 9 (30%) and 55 (67%) patients, respectively (p = 0.001). Median progression‐free survival was 7.5 mo in patients showing IGF‐1 negative tumors and 3 mo for IGF‐1 expressing tumors (p = 0.002). Among K‐RAS wild type patients, IGF‐1 negative and positive tumors showed a partial response to cetuximab‐irinotecan in 13 (65%) and 11 (22%) cases, respectively (p = 0.002). Median progression‐free survival in IGF‐1 negative tumors was 10 mo and 3.2 mo in IGF‐1 positive colorectal cancers (p = 0.02). IGF‐1 proved to be a possible predictive factor for resistance to anti‐EGFR monoclonal antibodies in K‐RAS wild type colorectal cancer. Combined IGF‐1 and K‐RAS analysis may represent an effective strategy for a better selection of responding colorectal cancer patients.

The Role of HER-3 Expression in the Prediction of Clinical Outcome for Advanced Colorectal Cancer Patients Receiving Irinotecan and Cetuximab

Preclinical data suggested that, in the presence of human epidermal growth factor receptor (HER)-3-altered activation, colorectal cancer cells may escape anti-epidermal growth factor receptor (EGFR)-mediated cell death. HER-3 overexpression may then represent a key factor for resistance to anti-EGFR antibodies in colorectal cancer. The aim of our analysis was to investigate a possible correlation between HER-3 expression and clinical outcome in wild-type K-RAS advanced colorectal cancer patients receiving cetuximab and irinotecan. We retrospectively analyzed immunoreactivity for HER-3 in wild-type K-RAS advanced colorectal cancer patients receiving irinotecan and cetuximab. Eighty-four advanced wild-type K-RAS colorectal cancer patients were available for HER-3 analysis. Forty patients (48%) had a HER-3(-) colorectal tumor, whereas the remaining 44 cases (52%) were deemed HER-3(+). In patients with HER-3(-) and HER-3(+) tumors, we observed a partial response in 17 (42%) and eight (18%) patients respectively; progressive disease occurred in 11 (35%) and 26 (53%) patients with HER-3(-) and HER-3(+) tumors, respectively (p = .003). The median progression-free survival time was 6.3 months in patients with HER-3(-) tumors and 2.8 months for those who had HER-3-overexpressing tumors (p < .0001). The median overall survival time was 13.6 months in patients showing HER-3(-) tumors and 10.5 months for those who had HER-3-expressing tumors (p = .01). HER-3 proved to be a predictive factor for clinical outcome in wild-type K-RAS colorectal cancer patients treated with cetuximab. Combined HER-3 and K-RAS analysis may represent an effective strategy for better selection of responding colorectal cancer patients.

Multiple Primary Sporadic Gastrointestinal Stromal Tumors in the Adult: An Underestimated Entity

Purpose: Gastrointestinal stromal tumors (GIST) are commonly regarded as solitary tumors. The occurrence of multiple lesions is considered an extraordinary event restricted to pediatric GISTs and rare hereditary conditions. Beyond these well-defined situations, the presentation of multiple synchronous lesions is commonly viewed as the result of the metastatic spreading of a single primary GIST. Based on this axiom, patients with multifocal disease are classified as advanced stage and treated as such. Whether, indeed, the detection of several lesions in sporadic adult GIST patients may be suggestive of phenomena of tumor multiplicity still needs to be clarified. Experimental Design: From a multicentric series of 442 consecutive cases, 26 of which with advanced disease, we selected 5 patients who presented up to three distinct GIST nodules. Five additional cases with similar characteristics were also contributed by two other institutions. The clonal relationship between the synchronous lesions was assessed by comparing KIT/PDGFRA mutation and microsatellite pattern. Results: An independent origin of the synchronous lesions was established in 6 of 10 cases. Notably, in one patient, one lesion arose in the peritoneum, which is ordinarily regarded as a site of metastasis. Conclusions: Our data indicate that a significant fraction of GIST patients with multifocal presentation are actually affected by multiple primary tumors, suggesting that mesenchymal GIST precursor cells of these individuals are somehow primed to transformation. Thus, in the presence of multifocal GIST manifestations, an accurate characterization of the different tumor sites should be undertaken for a proper patient staging and therapy planning.

Coeliac disease in Libyan children: A screening study based on the rapid determination of anti-transglutaminase antibodies

BACKGROUND Coeliac disease is a common disorder in North Africa; however, there are no data on coeliac disease prevalence in Libya. AIM (1) To determine coeliac disease prevalence in Libyan schoolchildren by screening with a rapid test for IgA anti-transglutaminase determination on a blood drop; (2) to evaluate the accuracy of the rapid anti-transglutaminase test. PATIENTS AND METHODS We screened 2920 students (1452 females and 1468 males) attending school in El Beida (Libya) by the rapid anti-transglutaminase test. Conventional ELISA anti-transglutaminase in rapid test positives and small intestinal biopsy in ELISA positives were performed for coeliac disease diagnosis. Conventional IgA anti-transglutaminase was performed also in 800 rapid test negative subjects. RESULTS The rapid anti-transglutaminase test was positive in 50/2920 (1.7%) subjects but only 20/50 were confirmed by the ELISA determination. The diagnosis of coeliac disease was biopsy-confirmed in 19 out of these 20. The serum ELISA IgA anti-transglutaminase was positive in 4 out of 800 rapid test negative children. Coeliac disease prevalence was 0.79-1.13%. CONCLUSIONS Coeliac disease in Libyan children is as common as in Europe, affecting around 1% of the general population. The rapid test for IgA anti-transglutaminase determination on a blood drop was not an efficient screening test.