Buccal mucosa cells as in vivo model to evaluate gefitinib activity in patients with advanced non small cell lung cancer.

PURPOSE: To evaluate the role of pretreatment and posttreatment expression in buccal mucosa cells of signal transduction proteins activated by epidermal growth factor receptor, including phosphorylated epidermal growth factor receptor (p-EGFR), phosphorylated mitogen-activated protein kinase (p-MAPK), and phosphorylated AKT (p-AKT), in predicting gefitinib activity in advanced non-small cell lung cancer patients. Expression of the same proteins was also assessed on corresponding tissue samples for comparison. Moreover, EGFR gene mutations and copy number were analyzed. EXPERIMENTAL DESIGN: Protein expression was evaluated by standard immunocytochemistry in buccal smears, obtained by scraping immediately before and after 2 weeks of gefitinib treatment, and in the available archival tumor specimens. EGFR gene mutations were evaluated by direct sequencing and gene copy number was determined by fluorescence in situ hybridization. Data were correlated with gefitinib toxicity and objective response. RESULTS: Fifty-eight patients with pretreated advanced non-small cell lung cancer were enrolled and nine of these patients (15%) showed an objective response to gefitinib (including two complete responses). Toxicity (P = 0.025) and baseline p-AKT expression in buccal mucosa cells (P = 0.061) showed a potential predictive role. On the contrary, the probability of achieving an objective response was not affected by pretreatment expression of EGFR, p-EGFR, and p-MAPK, either in buccal mucosa or in tumor tissue. Responders showed a nonstatistically significant trend toward a more pronounced reduction in the expression of p-EGFR, p-MAPK, and p-AKT after gefitinib treatment. Among responders, five of six (83%) tumors showed EGFR gene mutation, whereas none of the tumors from patients with stable or progressive disease did (P < 0.001). CONCLUSIONS: Epithelial cells obtained from buccal mucosa may be used to assess the pharmacodynamic effect of EGFR-targeted agents, and pretreatment p-AKT expression may be a possible predictive biomarker of in vivo gefitinib activity.

Refractory pleural small cell carcinoma in never smoker. A case report.

A 47-year-old woman who had never smoked was evaluated for chest wall pain, cough and dyspnea that proved to be due to neoplastic right pleural disease with effusion. Cytological examination of the pleural fluid and histological analysis of a biopsy specimen of the pleural mass obtained during thoracoscopy were consistent with a diagnosis of small cell carcinoma. The patient was treated with two lines of chemotherapy and with octreotide, but without any clinical or radiological benefit. Since there was immunohistochemical overexpression of epidermal growth factor receptor, the patient was treated with gefitinib. Despite an initial clinical improvement she died due to disease progression. This case of a refractory pleural small cell carcinoma, which is an extremely rare disease, is the first reported in a never smoker and the first to be fully characterized for EGFR status.

Predictors of gefitinib outcomes in advanced non-small cell lung cancer (NSCLC): study of a comprehensive panel of molecular markers.

A number of different clinical characteristics and molecular markers related to epidermal growth factor receptor (EGFR) activation have been reported to singly correlate with therapeutic activity of EGFR tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC). This study was designed to evaluate the predictive value on gefitinib outcomes of a comprehensive panel of molecular parameters in advanced NSCLC patients. EGFR and K-ras mutations were detected by direct sequencing on tumor DNA from paraffin embedded samples. EGFR and HER2 gene copy number was assessed by FISH. EGFR protein expression was quantified by immunohistochemistry. EGFR gene intron 1 polymorphism was assessed on genomic DNA isolated from venous whole blood samples. Ninety-one patients were prospectively enrolled and the overall gefitinib response rate was 18.7% (2 complete and 15 partial responses). Sex (p=0.005), non-smoking status (p=0.010), skin toxicity (p=0.020), EGFR gene mutations (p<0.001) and EGFR FISH positivity (p=0.016) were found to be associated with gefitinib response. K-ras mutation was detected in only seven non-responder patients. The median overall survival was of 10 months. Only non-smoking status and EGFR intron 1 polymorphism showed a statistically significant correlation with survival (p=0.031 and 0.044, respectively). In conclusion, we have confirmed the role of EGFR gene mutation as predictor of response to EGFR TKIs. Moreover, EGFR gene copy number and, potentially, also EGFR intron 1 polymorphism could aid in better prediction of EGFR TKI responsiveness in advanced NSCLC.

Comparison between epidermal growth factor receptor (EGFR) gene expression in primary non-small cell lung cancer (NSCLC) and in fine-needle aspirates from distant metastatic sites.

PURPOSE: Epidermal growth factor receptor (EGFR) gene copy number obtained by fluorescence in situ hybridization (FISH) has been recently found to predict treatment outcome in non-small cell lung cancer (NSCLC) patients receiving EGFR tyrosine kinase inhibitors. However, it is still unknown whether EGFR status differs in metastases compared with primary NSCLC. In all studies FISH have been performed on histologic material. The possibility to perform FISH analysis on cytologic material obtained by fine-needle aspiration from superficial and visceral metastases would allow us to know the real EGFR status avoiding invasive diagnostic procedures. METHODS: EGFR gene copy number was analyzed by FISH on fine-needle aspirates obtained from 31 patients with metastatic NSCLC and the results were compared with those obtained on corresponding paraffin histologic sections from the primary tumor. RESULTS: The feasibility of EGFR FISH on cytology was 90% (28 of 31 patients). EGFR FISH was positive in 61% (17 of 28 patients) of the metastases and in 36% (10 of 28 patients) of the primary tumors. Nine of the 28 cases (32%) were EGFR positive on both primary tumor and metastatic site and 10 (36%) were negative on both primary tumor and metastasis. Nine of the 28 cases (32%) showed discordance of primary tumor versus metastasis (McNemar test; p = 0.041). CONCLUSIONS: EGFR FISH can be reliably assessed on fine-needle aspirates obtained from NSCLC metastases. We found that EGFR gene copy number is discordant between primary NSCLC and the corresponding distant metastatic sites in a significant proportion of cases. These findings should be considered in future studies designed to elucidate the predictive role of EGFR FISH in NSCLC.