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Patrick Maisonneuve

Publications and source records attributed to Patrick Maisonneuve.

At least 37 records · Page 2Linked to original sources
PubMed2005

Alteration of the E-cadherin/beta-catenin cell adhesion system is common in pulmonary neuroendocrine tumors and is an independent predictor of lymph node metastasis in atypical carcinoids.

BACKGROUND: To the authors' knowledge, little is known regarding the role of E-cadherin/beta-catenin system dysregulation in pulmonary neuroendocrine tumors. METHODS: E-cadherin and beta-catenin immunoreactivity was evaluated in 10 hyperplastic neuroendocrine tumorlets and 210 neuroendocrine tumors, including 96 typical carcinoids (CTs), 35 atypical carcinoids (ACTs), 49 large cell neuroendocrine carcinomas (LCNECs), and 30 small cell lung carcinomas (SCLCs). RESULTS: Normal and hyperplastic bronchial neuroendocrine cells expressed E-cadherin/beta-catenin with an orderly distribution along the cell membrane. Neuroendocrine tumors retained beta-catenin expression in all tumors and E-cadherin in most tumors, with the exception of 2% of LCNECs, 3% of SCLCs and 9% of ACTs. E-cadherin showed a prevalent membrane-associated, linear immunoreactivity in CTs, whereas membrane-disarrayed and cytoplasmic staining was seen in most ACTs, LCNECs, and SCLCs (P < 0.001). beta-Catenin exhibited similar immunoreactivity patterns according to tumor type and a close association with E-cadherin subcellular distribution (P < 0.001). Nuclear accumulation of beta-catenin was found only in seven LCNECs and in two SCLCs. In ACTs, disarrayed immunoreactivity for E-cadherin and/or beta-catenin was associated with a nontrabecular growth pattern, altered expression of the cell-motility marker fascin, and lymph node metastases. Furthermore, a disarrayed E-cadherin distribution pattern was associated with the pathologic lymph node classification and the number of involved lymph nodes. Multivariate analysis confirmed that a disarrayed E-cadherin or beta-catenin pattern was an independent predictor of lymph node metastases in patients with ACT. CONCLUSIONS: The subcellular compartmentalization of the E-cadherin/beta-catenin complex was altered in pulmonary neuroendocrine tumors. This likely affects the tumor growth pattern and cell motility of ACT and was correlated with the occurrence of lymph node metastases.

Adult↗
PubMed2005

Incidence and risk factors for non-alcoholic steatohepatitis: prospective study of 5408 women enrolled in Italian tamoxifen chemoprevention trial.

OBJECTIVE: To assess the incidence, cofactors, and excess risk of development of non-alcoholic fatty liver disease, including non-alcoholic steatohepatitis, attributable to tamoxifen in women. DESIGN: Prospective, randomised, double blind, placebo controlled trial. SETTING AND PARTICIPANTS: 5408 healthy women who had had hysterectomies, recruited into the Italian tamoxifen chemoprevention trial from 58 centres in Italy. INTERVENTION: Women were randomly assigned to receive tamoxifen (20 mg daily) or placebo for five years. MAIN OUTCOME MEASURE: Development of non-alcoholic fatty liver disease in all women with normal baseline liver function who showed at least two elevations of alanine aminotransferase (> or = 1.5 times upper limit of normal) over a six month period. RESULTS: During follow up, 64 women met the predefined criteria: 12 tested positive for hepatitis C virus, and the remaining 52 were suspected of having developed non-alcoholic fatty liver disease (34 tamoxifen, 18 placebo)--hazard ratio = 2.0 (95% confidence interval 1.1 to 3.5; P = 0.04). In all 52 women ultrasonography confirmed the presence of fatty liver. Other factors associated with the development of non-alcoholic fatty liver disease included overweight (2.4, 1.2 to 4.8), obesity (3.6, 1.7 to 7.6), hypercholesterolaemia (3.4, 1.4 to 7.8), and arterial hypertension (2.0, 1.0 to 3.8). Twenty women had liver biopsies: 15 were diagnosed as having mild to moderate steatohepatitis (12 tamoxifen, 3 placebo), and five had fatty liver alone (1 tamoxifen, 4 placebo). No clinical, biochemical, ultrasonic, or histological signs suggestive of progression to cirrhosis were observed after a median follow up of 8.7 years. CONCLUSIONS: Tamoxifen was associated with higher risk of development of non-alcoholic steatohepatitis only in overweight and obese women with features of metabolic syndrome, but the disease, in both the tamoxifen and the placebo group, after 10 years of follow up seems to be indolent.

Adult↗
PubMed2005

Size of breast cancer metastases in axillary lymph nodes: clinical relevance of minimal lymph node involvement.

BACKGROUND: Overt ipsilateral axillary lymph node metastases of breast cancer are the most significant prognostic indicators for women who have undergone surgery, yet the clinical relevance of minimal involvement (isolated tumor cells and micrometastases) of these nodes is uncertain. PATIENTS AND METHODS: We evaluated biologic features, adjuvant treatment recommendations, and prognosis for 1,959 consecutive patients with pT1-3, pN0, minimal lymph node involvement (pN1mi or pN0i+), or pN1a (single positive node) and M0, who were operated on and counseled for medical therapy from April 1997 to December 2000. RESULTS: Patients with pN1a and pN1mi/pN0i+, when compared with patients with pN0 disease, were more often prescribed anthracycline-containing chemotherapy (39.1% v 33.2% v 6.1%, respectively; P < .0001) and were less likely to receive endocrine therapy alone (9.8% v 19.4% v 41.9%, respectively; P < .0001). At the multivariate analysis, a statistically significant difference in disease-free survival (DFS) and in the risk of distant metastases was observed for patients with pN1a versus pN0 disease (hazard ratio [HR] = 2.04; 95% CI, 1.46 to 2.86; P < .0001 for DFS; HR = 2.32; 95% CI, 1.42 to 3.80; P = .0007 for distant metastases) and for patients with pN1mi/pN0i+ versus pN0 disease (HR = 1.58; 95% CI, 1.01 to 2.47; P = .047 for DFS; HR = 1.94; 95% CI, 1.04 to 3.64; P = .037 for distant metastases). CONCLUSION: Even minimal involvement of a single axillary node in breast cancer significantly correlates with worse prognosis compared with no axillary node involvement. Further studies are required before widespread modification of clinical practice.

Adult↗
PubMed2005

Effect of tamoxifen on venous thromboembolic events in a breast cancer prevention trial.

BACKGROUND: Tamoxifen, a selective estrogen-receptor modulator, increases venous thromboembolic events (VTE), but the factors explaining this risk are unclear. Atherosclerosis may induce VTE, or the 2 conditions may share common risk factors. We assessed the effect of tamoxifen on VTE in a breast cancer prevention trial and studied its association with risk factors for VTE. METHODS AND RESULTS: The incidence of VTE was studied in 5408 hysterectomized women randomly assigned to tamoxifen 20 mg/d or placebo for 5 years. There were 28 VTEs on placebo and 44 on tamoxifen therapy (hazard ratio [HR]=1.63; 95% confidence interval [CI], 1.02 to 2.63), 80% of which were superficial phlebitis, accounting for all of the excess due to tamoxifen within 18 months from randomization. Compared with placebo, the risk of VTE on tamoxifen was higher in women aged 55 years or older, women with a body mass index > or =25 kg/m2, elevated blood pressure, total cholesterol > or =250 mg/dL, current smoking, and a family history of coronary heart disease (CHD). Of the 685 women with a CHD risk score > or =5 who entered the trial, 1 in the placebo arm and 13 in the tamoxifen arm developed VTE (log-rank P=0.0013). In multivariate regression analysis, age > or =60 years, height > or =165 cm, and diastolic blood pressure > or =90 mm Hg had independent detrimental effects on VTE risk during tamoxifen therapy, whereas transdermal estrogen therapy concomitant with tamoxifen was not associated with any excess of VTE (HR=0.64; 95% CI, 0.23 to 1.82). CONCLUSIONS: Women with conventional risk factors for atherosclerosis have a higher risk of VTE during tamoxifen therapy. This information should be incorporated into counseling women on its risk-benefit ratio, particularly in the prevention setting.

Adult↗
PubMed2005

Predicting the status of axillary sentinel lymph nodes in 4351 patients with invasive breast carcinoma treated in a single institution.

BACKGROUND: Reliable predictors of metastatic involvement would enable a better selection of candidate patients for sentinel lymph node biopsy (SLNB) and possibly allow identification of patients with such a low risk of axillary sentinel lymph node (SLN) involvement to be even spared SLNB. METHODS: The authors evaluated 4351 consecutive patients surgically treated for breast carcinoma who also underwent SLNB. Clinicopathologic features significantly associated with SLN metastases by univariate analysis were included in a multivariate model. RESULTS: By multivariate analysis, the prevalence of SLN metastases was associated directly with tumor size, multifocality, and with the occurrence of peritumoral vascular invasion (PVI; all P < 0.0001), and was associated inversely with a favorable histotype (P = 0.0007) and lack of progesterone receptors (P = 0.004). A predictive model based on the features more closely associated with SLN status documented that the patients with a favorable tumor type </= 1 cm in size and without PVI (n = 178 [4% of the population]) had the lowest risk of SLN metastases (9.5%) whereas patients with tumors > 2 cm and with PVI (n = 250 [5.7% of the population]) had the highest risk (77.2%) of SLN involvement. CONCLUSIONS: Tumor size and PVI emerged as the most powerful independent predictors of SLN metastases. Although no combination of features identified patients with a < 9.5% risk of SLN metastases, the current data may be used to tailor the management of patients with breast carcinoma with the aim of minimizing as much as possible the diagnostic and therapeutic procedures, thus improving the quality of life of the patients without any adverse effect on their survival rates.

Adolescent↗
PubMed2005

Lack of prognostic implications of HER-2/neu abnormalities in 345 stage I non-small cell carcinomas (NSCLC) and 207 stage I-III neuroendocrine tumours (NET) of the lung.

HER-2/neu oncogene activation by either gene amplification and/or protein overexpression has been documented in several human malignancies. Irrespective of protein overexpression, HER-2/neu gene amplification is rare in lung cancer and studies on its prevalence and clinicopathological implications in early stage non-small cell lung cancer (NCSLC) and neuroendocrine tumours (NET) of the lung are lacking. We evaluated HER-2/neu abnormalities in 345 Stage I NSCLC and 207 Stage I-III NET of the lung of all the diverse histological types, by using immunohistochemistry and fluorescent in situ hybridization in selected cases. Overall, HER-2/neu immunoreactivity was detected in 23% of 345 NSCLC and in 7% of 207 NET. Gene amplification was seen in only 7 (7.4%) of the immunoreactive tumours, with high-level amplification (HER-2/neu gene to chromosome 17 ratio > 4.0) in 3 adenocarcinomas, 1 squamous-cell carcinoma and 1 large-cell neuroendocrine carcinoma (LCNEC), and low-level amplification (HER-2/neu gene to chromosome 17 ratio from 2.0 to 4.0) in 1 squamous-cell carcinoma and 1 LCNEC. None of tested carcinoids and SCLC showed gene amplification. All but 1 gene amplified case exhibited 2+ or 3+ membrane labeling. No relationship was found between gene amplification or protein overexpression and patients' survival or other clinicopathological variables. HER-2/neu gene amplification and protein overexpression are not closely correlated in lung carcinomas and do not bear any prognostic implication. Among neuroendocrine tumours, LCNEC show a slightly higher prevalence of either HER-2/neu gene amplification or protein overexpression.

Adenocarcinoma↗
PubMed2005

Cyclin D3 immunoreactivity is an independent predictor of survival in laryngeal squamous cell carcinoma.

PURPOSE: To analyze the prevalence and clinical relevance of cyclin D3 abnormalities in laryngeal squamous cell carcinoma (LSCC). EXPERIMENTAL DESIGN: Cyclin D3 immunoreactivity was evaluated in 223 formalin-fixed and paraffin-embedded samples of LSCC patients with a mean follow-up of 62.8 +/- 43.2 months. The occurrence of cyclin D3 extra signals was analyzed by fluorescence in situ hybridization in 47 randomly selected cases collected in a tissue microarray. Cyclin D1 immunoreactivity had been previously investigated in 133 cases. RESULTS: Cyclin D3 immunoreactivity and gene extra signals were found in 39.5% and 42.6% of the cases, respectively, and the concordance between immunohistochemical and fluorescence in situ hybridization results was 70.2% (P = 0.0085). Cyclin D3 immunoreactivity was significantly associated with a high risk of death. Multivariate analysis showed that high tumor grade, exophytic/ulcerating tumor type, low performance status, and cyclin D3 immunoreactivity were the only independent predictors of poor overall survival. In the 133 cases analyzed for both cyclin D1 and cyclin D3, patients with cyclin D1+/cyclin D3+ tumors experienced the worst prognosis, patients with cyclin D1-/cyclin D3- exhibited the most prolonged survival, and with cyclin D1-/cyclin D3+ or cyclin D1+/cyclin D3- tumors an intermediate course was associated. CONCLUSIONS: Our data suggest that cyclin D3 immunoreactivity, possibly due to the occurrence of gene extra copies, may represent an adjunct in LSCC patients' prognostication and contribute to identify D-type cyclins as potential targets of newly developed therapies.

Adult↗
PubMed2005

The epidemiology and impact of pancreatic diseases in the United States.

In the United States, acute pancreatitis, chronic pancreatitis, and pancreatic cancer are the most common pancreatic disorders requiring diagnosis and treatment. Pancreatic cancer is responsible for nearly 30,000 annual deaths and is the second most common cause of death from any type of gastrointestinal disease. Gallstone disease, which is strongly associated with obesity, and excessive consumption of alcohol are the major risk factors for benign pancreatic disease, whereas smoking is the most important factor known to cause pancreatic cancer. Therefore, to reduce the overall burden of pancreatic disease, we should focus on the control of three lifestyle factors: smoking, drinking, and obesity.

Comorbidity↗
PubMed2005

Malignancy-associated X chromosome allelic losses in foregut endocrine neoplasms: further evidence from lung tumors.

Association of X chromosome allelic losses with tumor malignancy has been identified in foregut but not in midgut endocrine neoplasms. The aim of this study was to investigate the association of deletions on X chromosome with malignancy in lung neuroendocrine tumors, another family of foregut neoplasms comprising four categories with increased malignancy: typical and atypical carcinoids, large cell neuroendocrine and small cell lung carcinomas. To evaluate loss of heterozygosity, DNA extracted from nine typical carcinoids, 17 atypical carcinoids, six large cell neuroendocrine carcinomas and five small cell lung carcinomas was PCR-amplified for 18 microsatellite markers spanning the whole X chromosome. All tissue samples were formalin-fixed and paraffin-embedded. X chromosome losses were absent in typical carcinoids, whereas they were found in nine out of 17 atypical carcinoids and in five out of six large cell neuroendocrine carcinomas (involving 28 and 70% of informative loci, respectively). On the contrary, deletions on X chromosome were an extremely rare event in small cell lung carcinomas. In atypical carcinoids, the presence of losses was associated with larger tumor size, higher pT status and advanced stage. No death occurred in atypical carcinoid patients without deletions on X chromosome, whereas all atypical carcinoid patients who had died from disease showed allelic losses. In conclusion, X chromosome allelic losses, absent in benign 'typical' carcinoids, progressively increased in frequency from intermediate-grade 'atypical' carcinoids to high-grade large cell neuroendocrine carcinomas. These results extend the association of deletions on X chromosome with malignancy, already demonstrated in other foregut endocrine neoplasms, to lung neuroendocrine tumors. The absence of X chromosome allelic losses in small cell lung carcinomas underlines a striking difference from large cell neuroendocrine carcinomas, possibly linked to different pathogenetic mechanisms of these two highly aggressive neuroendocrine lung tumors.

Adult↗
PubMed2005

Predicting the risk for additional axillary metastases in patients with breast carcinoma and positive sentinel lymph node biopsy.

OBJECTIVE: To assess whether the risk for nonsentinel node metastases may be predicted, thus sparing a subgroup of patients with breast carcinoma and a positive sentinel lymph node (SLN) biopsy completion axillary lymph node dissection (ALND). SUMMARY BACKGROUND DATA: The SLN is the only involved axillary lymph node in the majority of the patients undergoing ALND for a positive SLN biopsy. A model to predict the status of nonsentinel axillary lymph nodes could help tailor surgical therapy to those patients most likely to benefit from completion ALND. METHODS: All the axillary sentinel and nonsentinel lymph nodes of 1228 patients were reviewed histologically and reclassified according to the current TNM classification of malignant tumors as bearing isolated tumor cells only, micrometastases, or (macro)metastases. The prevalence of metastases in nonsentinel lymph nodes was correlated to the type of SLN involvement and the size of the metastasis, the number of affected SLNs, and the prospectively collected clinicopathologic variables of the primary tumors. RESULTS: In multivariate analysis, further axillary involvement was significantly associated with the type and size of SLN metastases, the number of affected SLNs, and the occurrence of peritumoral vascular invasion in the primary tumor. A predictive model based on the characteristics most strongly associated with nonsentinel node metastases was able to identify subgroups of patients at significantly different risk for further axillary involvement. CONCLUSIONS: Patients with the most favorable combination of predictive factors still have no less than 13% risk for nonsentinel lymph node metastases and should be offered completion ALND outside of clinical trials of SLN biopsy without back-up axillary clearing.

Adult↗
PubMed2005

Allergies and the risk of pancreatic cancer: a meta-analysis with review of epidemiology and biological mechanisms.

Previous reports suggest that allergic disorders may protect against various types of cancer, but the association between history of allergy and pancreatic cancer risk has not been well studied. We did a systematic review and meta-analysis of published studies to evaluate the association of any type, and specific types, of allergy and the risk of pancreatic cancer. We did a comprehensive literature search using MEDLINE, PUBMED, and the ISI Web of Science databases to identify potential relevant case-control and cohort studies. Pooled relative risks (RR) and 95% confidence intervals (95% CI) were calculated using the fixed- and random-effects model. Fourteen population-based studies (4 cohort and 10 case-control studies) with a total of 3,040 pancreatic cancer cases fulfilled our inclusion criteria. A history of allergy was associated with a reduced risk of pancreatic cancer (RR, 0.82; 95% CI, 0.68-0.99). The risk reduction was stronger for allergies related to atopy (RR, 0.71; 95% CI, 0.64-0.80), but not for asthma (RR, 1.01; 95% CI, 0.77-1.31). There was no association between allergies related to food or drugs and pancreatic cancer (RR, 1.08; 95% CI, 0.74-1.58). Overall, there was no evidence of publication bias. Allergies, in particular those related to atopy, seem to be associated with a decreased risk of pancreatic cancer. The hyperactive immune system of allergic individuals may, therefore, in some way lead to increased surveillance and protect against pancreatic cancer development.

Female↗
PubMed2005

Frequency of K-ras mutations in pancreatic intraductal neoplasias associated with pancreatic ductal adenocarcinoma and chronic pancreatitis: a meta-analysis.

Molecular analyses have demonstrated mutations in the K-ras gene at codon 12 in the majority of pancreatic ductal adenocarcinomas (PDACs). In order to determine whether the K-ras mutation rate increases parallel to the grade of dysplasia in duct lesions, we performed a meta-analysis of the studies published between 1988 and 2003 that provide information on K-ras mutations in hyperplastic and dysplastic duct lesions in the pancreas. The described duct lesions were reclassified according to the nomenclature for pancreatic intraepithelial neoplasia (PanIN), and the molecular methods for detecting K-ras were reviewed. In PanIN lesions from pancreata of patients with PDAC, there was a stepwise increase in K-ras mutations that correlated with the grade of dysplasia of the PanIN lesion. K-ras mutations were found in 36%, 44%, and 87% of PanIN-1a, 1b, and 2-3 lesions, respectively (trend statistic P <.001). Mutation-enriched polymerase chain reaction (PCR) resulted in higher rates of K-ras mutations in PanIN than plain PCR did. The incidence of K-ras mutations in PanIN lesions associated with chronic pancreatitis (CP) or normal pancreas was low (around 10%). In CP, K-ras mutations were only found after a disease duration of 3 years. The correlation of the incidence of K-ras mutations with the grade of dysplasia in PanIN and the occurrence of these mutations in CP with a duration of more than 3 years underlines the importance of this genetic change for the development of PDAC.

Adenocarcinoma↗
PubMed2004

Loss of negative regulation by Numb over Notch is relevant to human breast carcinogenesis.

The biological antagonism between Notch and Numb controls the proliferative/differentiative balance in development and homeostasis. Although altered Notch signaling has been linked to human diseases, including cancer, evidence for a substantial involvement of Notch in human tumors has remained elusive. Here, we show that Numb-mediated control on Notch signaling is lost in approximately 50% of human mammary carcinomas, due to specific Numb ubiquitination and proteasomal degradation. Mechanistically, Numb operates as an oncosuppressor, as its ectopic expression in Numb-negative, but not in Numb-positive, tumor cells inhibits proliferation. Increased Notch signaling is observed in Numb-negative tumors, but reverts to basal levels after enforced expression of Numb. Conversely, Numb silencing increases Notch signaling in normal breast cells and in Numb-positive breast tumors. Finally, growth suppression of Numb-negative, but not Numb-positive, breast tumors can be achieved by pharmacological inhibition of Notch. Thus, the Numb/Notch biological antagonism is relevant to the homeostasis of the normal mammary parenchyma and its subversion contributes to human mammary carcinogenesis.

Breast Neoplasms↗
PubMed2004

Prognosis of papillary serous, clear cell, and grade 3 stage I carcinoma of the endometrium.

OBJECTIVE: The purpose of this study was to evaluate patients with uterine papillary serous carcinoma (UPSC), clear cell (CC), and grade 3 endometrioid (G3) surgically stage I endometrial cancer. METHODS: The 25th Annual Report (AR) of FIGO was used to identify patients with endometrial cancers who were surgically staged. For comparison, all cancers reported were evaluated with particular interest in patients with stage I UPSC, CC, and G3. Incidence, substage, post-surgical treatment, and survival were identified. RESULTS: Of 5694 endometrial cancer patients reported to the AR, 3996 (70%) were surgically stage I. There were 148 UPSC, 59 CC, and 325 with G3 lesions. UPSC and CC represent 5.2% of all stage I cancers while 8.1% are G3. Although there were greater number of UPSC, CC, and G3 with extrauterine disease, about 50% of UPSC and CC were stage I. This compares to 81% for G1, 68% for G2, and only 42% for G3. There were more IA cancers with UPSC and CC than G3 (22%, 33%, and 17%, respectively). Survival (5 years) for UPSC and CC was 72% and 81%, respectively, compared to 76% for G3 lesions. Postoperative radiation improved survival somewhat (6-8%) but the difference was not significant. CONCLUSION: UPSC and CC histotypes when diagnosed as stage I have a better survival than commonly perceived and equal to G3 endometrioid cancers. Postoperative radiation improves survival but not significantly so. The role of chemotherapy has not been defined.

Adenocarcinoma↗
PubMed2004

Pancreatitis in hispanic patients with cystic fibrosis carrying the R334W mutation.

BACKGROUND & AIMS: Cystic fibrosis (CF) results from abnormal production of sticky mucus, which obstructs many organs. In most cases, the pancreas is severely compromised, but 10%-15% of patients with CF have pancreas sufficiency (PS) and are subject to develop pancreatitis. The aim of this study is to determine which specific genotypes lead to the development of pancreatitis in patients with CF. METHODS: We used prospective data collected by the Cystic Fibrosis Foundation and performed a nested case-control study with all patients who reported at least 1 episode of pancreatitis constituting the cases. We used logistic regression to assess the association between pancreatitis and genotype and the Kaplan-Meier method to estimate the cumulative incidence of pancreatitis for selected genotypes. RESULTS: Three hundred sixty-four of 17,871 genotyped patients with CF (2.0%) reported at least 1 episode of pancreatitis. Only 0.9% of 12,997 patients with genotypes generally associated with pancreas insufficiency reported pancreatitis against 11.9% of 868 patients carrying at least 1 mild CF mutation generally associated with PS. The greatest rate of pancreatitis (19.0%) was observed for patients carrying an R334W mutation: 48% of these 79 patients were Hispanic and 13 patients were living in Puerto Rico. CONCLUSIONS: Of all patients with CF, those carrying an R334W mutation have the greatest risk for developing pancreatitis. This mutation is found mostly in Hispanic patients with CF living in Puerto Rico. There are no current data to determine whether asymptomatic carriers of the R334W mutation are at greater risk for developing pancreatitis or whether this mutation is frequent in Hispanics with idiopathic pancreatitis.

Adolescent↗
PubMed2004

K-ras gene mutational analysis supports a monoclonal origin of biphasic pleomorphic carcinoma of the lung.

We investigated 27 pleomorphic carcinomas of the lung for exon 1 K-ras gene mutations using polymerase chain reaction-single-strand conformation polymophism analysis and direct sequencing. All pleomorphic carcinomas were biphasic, that is, composed of an adeno-, squamous- or large-cell-carcinomatous component associated with a spindle- and/or giant-cell component. Of 27 cases, six (22%) showed K-ras codon 12 mutations, which is a figure higher than that previously reported on in pure sarcoma-like pleomorphic carcinomas. Five tumors displayed the same mutation in both the epithelial and the sarcomatoid components, whereas in one tumor the mutation was restricted to the epithelial component. All mutations occurred in smokers, and were transversions, including GGT (glycine) to TGT (cysteine) change in two cases, to GCT (alanine) in two and to GTT (valine) in two. No significant relationships were found between the occurrence and type of mutations and patients' survival or any other clinicopathological variable, suggesting that K-ras mutations are early events in the development of these tumors. Our results indicate that most, though not all, biphasic pleomorphic carcinomas of the lung are monoclonal in origin, and that cigarette smoking may have a causative role in the development of K-ras alterations in these tumors, as all mutations are transversions.

Adenocarcinoma↗
PubMed2004

Epidemiology and prevention of pancreatic cancer.

Pancreatic cancer is an uncommon tumor, but because the mortality rate approaches 100%, this form of cancer has now become a common cause of cancer mortality. In the United States it is the fourth most frequent cause of cancer mortality; in Japan it ranks as the fifth commonest cause of death from cancer. Smoking is the major known risk factor for pancreatic cancer, accounting for approximately 25-30% of all cases. Some of the time-dependent changes in the frequency of pancreatic cancer can be explained by smoking trends. Aggressive public health measures to control smoking would substantially reduce the burden of pancreatic cancer. Dietary factors are less important for pancreatic cancer than for other digestive tract tumors, but consumption of a diet with adequate quantities of fruits and vegetables, plus control of calories either by dietary measures or by exercise will help to prevent this lethal tumor. There are more than a dozen inherited germline mutations that increase the risk of pancreatic cancer. Of these, hereditary pancreatitis confers the greatest risk, while BRCA2 mutations are the commonest inherited disorder. In addition to germline defects, there are several common polymorphisms in genes that control detoxification of environmental carcinogens that may alter the risk of pancreatic cancer. More research will be needed in this area, to explain and to clarify the interaction between genes and environmental factors.

Aged↗