Cecilia Bozzetti

Comparison of HER2 status in primary and paired metastatic sites of gastric carcinoma

Background:Trastuzumab has recently shown efficacy in the treatment of HER2-positive advanced gastric adenocarcinoma. Although antibody-based therapies target the metastatic disease, HER2 status is usually evaluated in the primary tumour because metastatic sites are rarely biopsied. The aim of this study was to compare HER2 status in primary and paired metastatic sites of gastric adenocarcinoma.Methods:The HER2 status was assessed by fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) in 72 secondary lesions of gastric adenocarcinoma and in the corresponding primary tumours.Results:Concordance of FISH results, evaluable in 68 primary and matched metastatic sites, was 98.5%. Concordance of IHC results, available in 39 of the 72 paired cases, was 94.9%. Only one case showed discordance between primary tumour and metastasis, being negative by both IHC and FISH in the primary and showing HER2 overexpression and amplification in the corresponding pancreatic lymph node metastasis.Conclusion:The high concordance observed between HER2 results obtained by both IHC and FISH on primary tumours and corresponding metastases suggests that in gastric cancer HER2 status is maintained in most cases unchanged during the metastatic process.

EGFR and EML4-ALK gene mutations in NSCLC: A case report of erlotinib-resistant patient with both concomitant mutations

The fusion gene EML4-ALK (echinoderm microtubule-associated protein-like 4 gene and the anaplastic lymphoma kinase gene) was recently identified as a novel genetic alteration in non-small cell lung cancer (NSCLC). EML4-ALK translocations correlate with specific clinical and pathological features, in particular lack of EGFR and K-ras mutations, and may be associated with resistance to EGFR tyrosine-kinase inhibitors (TKIs). Here, we report a case of a patient with a concomitant EGFR mutation and ALK translocation resistant to erlotinib. Considering this report, ALK status should be investigated in unexplained cases of EGFR-TKI-resistance of EGFR mutated NSCLCs.

PTEN status in advanced colorectal cancer treated with cetuximab

Background:Loss of phosphatase and tensin homologue deleted in chromosome 10 (PTEN) function in advanced colorectal cancer (CRC) may represent one of the resistance mechanisms to cetuximab by interfering with the epidermal growth factor receptor signal transduction pathway.Methods:PTEN expression tested by indirect immunofluorescence was evaluated both on primary (n=43) and on metastatic (n=24) sites in CRC patients treated with cetuximab.Results:The loss of PTEN expression tested on metastatic sites was negatively associated with response (100% progressive disease (PD) in PTEN-negative cases vs 30% PD in PTEN-positive cases; P<0.05), PFS (0.8 vs 8.2 months; P<0.001) and OS (2.9 vs 14.2 months; P<0.001).Conclusion:A potential role of PTEN in the anti-tumour activity of cetuximab could be hypothesised.

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 of the results of immunocytochemical assays for biologic variables on preoperative fine‐needle aspirates and on surgical specimens of primary breast carcinomas

Fine‐needle aspiration biopsy (FNAB) is a well‐documented procedure for the diagnosis and biologic characterization of breast carcinoma. In order to compare the immunocytochemical expression of biologic parameters on cytology and on histology, estrogen receptor (ER) and progesterone receptor (PgR) status, p53 protein expression, and Ki67 growth fraction were evaluated on presurgical fine‐needle aspirates (FNAs) from breast carcinoma patients and on the corresponding surgical samples prior to any systemic therapy.

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.

HER-2/neu amplification by fluorescence in situ hybridization in cytologic samples from distant metastatic sites of breast carcinoma

Amplification of the HER‐2/neu oncogene has been proposed as a target for antibody‐based therapies and as a predictor of chemoresponsiveness in advanced breast carcinoma. Few studies have concentrated on HER‐2/neu gene evaluation by fluorescence in situ hybridization (FISH) on distant metastatic sites and none have been performed on cytologic samples. The current study evaluated HER‐2/neu amplification by FISH on cytologic samples obtained from distant metastatic lesions of breast carcinoma to update HER‐2/neu characterization through a safe and easier procedure than biopsy.

Evaluation of HER-2/neu amplification and other biological markers as predictors of response to neoadjuvant anthracycline-based chemotherapy in primary breast cancer: the role of anthracycline dose intensity.

Objectives:The value of HER-2/neu status as a predictor of response to anthracycline-based chemotherapy is still a matter of debate. We evaluated the contribution of HER-2/neu gene amplification and other biologic markers in predicting response to different doses of neoadjuvant anthracycline-based chemotherapy. Methods:Clinical and pathologic records of 115 primary breast cancer patients were reviewed. Forty-eight and 67 patients received high (doxorubicin ≥20 mg/m2/wk; epirubicin ≥30 mg/m2/wk) and moderate-low anthracycline dose intensity regimens, respectively. Pathologic diagnosis, hormonal receptor status (HR), Ki67, and HER-2/neu status were assessed on tumor samples before neoadjuvant chemotherapy. HER-2/neu was determined by fluorescence in situ hybridization (FISH). Results:HER-2/neu amplification was observed in 29/115 (25%) tumors, 18 from moderate-low-dose and 11 from high-dose group. In the univariate analysis, a high Ki67 index (≥20%) and positive clinical axillary nodes were predictive of an objective tumor response (P = 0.033 and 0.001, respectively). In the multivariate analysis, Ki67 was the only factor predictive of response (OR = 3.08, 95% CI = 1.1–8.5, P = 0.03). HER-2/neu status was not a factor in predicting objective response to different anthracycline dose intensities. The same finding was observed with regards to HR and Ki67. Conclusions:In our series, no significant dose-response relationship was found according to HER-2/neu status.

L718Q Mutation as New Mechanism of Acquired Resistance to AZD9291 in EGFR-Mutated NSCLC

Abstract With the advent of third-generation epidermal growth-factor receptor (EGFR) tyrosine kinase inhibitors, such as AZD9291 and CO-1686, new mechanisms of drug resistance are emerging, like C797S and L884V EGFR mutations, in patients with EGFR T790M-positive non-small cell lung cancer (NSCLC). Here we present a case of advanced NSCLC with coexisting primary L585R and secondary T790M EGFR mutations that acquired resistance to AZD9291 (osimertinib) due to the occurrence of the tertiary L718Q mutation. This is the first clinical report for this new mutation as EGFR-dependent mechanism of resistance to AZD9291.

Epidermal Growth Factor Receptor Intron-1 Polymorphism Predicts Gefitinib Outcome in Advanced Non-small Cell Lung Cancer

Introduction: Epidermal growth factor receptor (EGFR) gene intron 1 contains a polymorphic single sequence dinucleotide repeat (CA)n whose length has been found to inversely correlate with transcriptional activity. This study was designed to assess the role of (CA)n polymorphism in predicting the outcome of gefitinib treatment in advanced non-small cell lung cancer (NSCLC). Methods: Blood and tumor tissue from 58 patients with advanced NSCLC submitted to gefitinib were collected. EGFR intron 1 gene polymorphism, along with EGFR gene mutation, gene copy number and immunohistochemistry expression were determined. Moreover, a panel of lung cancer cell lines characterized for EGFR intron 1 polymorphism was also studied. Results: EGFR intron 1 polymorphism showed a statistically significant correlation with the gefitinib response (response rate 25 versus 0%, for patients with a (CA)16 and with a (CA)else genotype, respectively; p = 0.044). Patients with a (CA)16 genotype had a longer survival compared with those with a (CA)else genotype (11.4 versus 4.8 months, respectively; p = 0.037). In addition, cell lines lacking the (CA)16 allele showed a statistically significant higher IC50 compared with cell lines bearing at least one (CA)16 allele (p = 0.003). Conclusions: This study supports a potential role of EGFR intron 1 polymorphism in predicting the outcome of gefitinib treatment in advanced NSCLC.