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A J Torres

Publications and source records attributed to A J Torres.

At least 19 recordsLinked to original sources
PubMed2005

Overexpression of c-myc and loss of heterozygosity on 2p, 3p, 5q, 17p and 18q in sporadic colorectal carcinoma.

AIM: The aim of the present study is to evaluate the prognostic influence of loss of heterozygosity on 2p, 3p, 5q, 17p and 18q, and c-myc overexpression on surgically treated sporadic colorectal carcinoma. METHODS: Tumor and non-tumor tissue samples from 153 patients were analyzed. Fifty-one percent of patients were male, and mean age in the series was 67 years. Tumors were located in the proximal colon in 37 cases, in the distal bowel in 37, and in the rectum in 79 patients. c-myc overexpression was studied by means of Northern blot analysis, and loss of heterozygosity through microsatellite analysis. RESULTS: c-myc overexpression was detected in 25% of cases, and loss of heterozygosity in at least one of the studied regions in 48%. There was no association between clinical and pathologic features, and genetic alterations. The disease-free interval was significantly shorter for patients with both genetic alterations; the presence of both events was an independent prognostic factor for poor outcome in the multivariate analysis (RR: 4.34, p < 0.0001). CONCLUSIONS: The presence of both loss of heterozygosity and overexpression of the c-myc oncogene separates a subset of colorectal carcinoma patients who have a shorter disease-free interval after curative-intent surgery.

Adult↗
PubMed2005

Clinical relevance of MMP-9, MMP-2, TIMP-1 and TIMP-2 in colorectal cancer.

The main aim of this study was to evaluate the clinical relevance of Gelatinases in colorectal cancer (CRC). Ninety-five CRCs and their paired normal tissues were investigated to detect total levels of MMP-9, MMP-2, and the tissue inhibitors TIMP-1 and TIMP-2. Also, pro-MMP and MMP activity, and potential associations with clinical parameters were estimated. MMP-9, MMP-2 and TIMP-1 levels were greater in CRCs than in normal tissues, differences being significant for MMP-9 and TIMP-1. However, TIMP-2 showed significantly lower levels in tumour samples. Moreover, significant differences in the state of activation between gelatinases were found. TIMP-1 low levels were significantly associated with poor clinical outcome of patients. According to these data, different roles have to be attributed to MMP-2 and MMP-9 in CRC progression. Moreover, TIMP-1 level evaluation emerges as the main prognostic factor in relation to Gelatinases A and B activity in CRC.

Adenocarcinoma↗
PubMed2001

Ischaemic colitis.

Explore the source record for details and available documents.

Colitis, Ischemic↗
PubMed2000

Cefminox versus metronidazole plus gentamicin intra-abdominal infections: a prospective randomized controlled clinical trial.

BACKGROUND: The aim of this prospective study was to compare the safety and efficacy of a new cephamycin, cefminox 2 g/12 h, to those of the usual regimen combining metronidazole 500 mg/8 h and gentamicin 80 mg/8 h (M+G). PATIENTS AND METHODS: 160 patients with clinically proven intra-abdominal infection were prospectively included in an open parallel randomized comparative multicenter trial. Antibiotics were started preoperatively and discontinued after clinical and laboratory evidence of resolution of the infection. Serum and peritoneal fluid levels and serum bactericidal activities were also studied. RESULTS: 150 patients were clinically evaluable. There was one failure in the cefminox group and three in the M+G group (not significant, RR: 1.07, 95% CI: 1-1.15). No differences were found in the number of wound infections, length of stay or duration of antibiotic therapy. Adverse effects were reported in 11 cases, all of them mild to moderate. Escherichia coli and Bacteroides fragilis were the most frequently found microorganisms. CONCLUSION: Cefminox is as effective and as safe as M+G in the treatment of intra-abdominal infections.

Abdomen↗
PubMed2000

Prognostic value of the quantified expression of p185 in non-small cell lung cancer.

BACKGROUND: We sought to assess the relationship between tissue concentration of erb -b-2 or neu oncogene-encoded protein (p185(neu)) with overall survival in patients with non-small cell lung cancer. METHODS: Levels of protein p185(neu) were determined in 102 patients with the diagnosis of non-small cell lung cancer. Concentration of p185(neu) protein was determined by using enzyme immunoassay and evaluated by using several variables. The relative prognostic importance of this marker and its influence on other prognostic factors was evaluated by using the Cox regression model. RESULTS: The mean p185(neu) value in these samples was 250 +/- 200 U/mg (95% confidence interval, 210-290). This distinguished two groups within the tumoral population: those with less than 350 U/mg and those with 350 U/mg or greater (80th percentile). Multivariable analysis established an independent prognostic value for protein p185(neu). Patients with p185(neu) values of the 80th percentile or greater had a risk of death that was 2.11-fold (95% confidence interval, 1.10-4.05) that of patients with values of less than 350 U/mg (P =.03), and increases in the neu oncogene of 100 U/mg increased the probability of death by 17% (P =.02; 95% confidence interval, 1.04-1.31). CONCLUSION: This study shows that the p185(neu) expression is an objective and comparable variable for the assessment of phenotypic aggressivity in non-small cell lung cancer, and in the future, it could be included in daily clinical practice.

Adult↗
PubMed1999

DNA amplification on chromosome 6p12 in non small cell lung cancer detected by arbitrarily primed polymerase chain reaction.

Gene amplification is clearly an important aspect of tumour growth and development and has prognostic significance in certain tumours. The identification and genetic characterisation of new areas of amplification in human malignancy remains an important goal in understanding the underlying genetic lesions within these tissues. In the present work, arbitrarily primed-PCR (AP-PCR) has been applied to detect and characterise amplified DNA fragments in human non small cell lung cancer (NSCLC). Our results show that gains of genomic sequences occur at high frequency (64% of all genomic changes analysed). Moreover, we succeeded in detecting a genomic sequence that is highly amplified in one of the tumours analysed. The amplification intensity of this DNA fragment was also increased in 29 (45%) of the 65 NSCLC patients from our study. The amplified DNA fragment was isolated and identified as a 600 bp sequence mapped to chromosome 6p12. This sequence did not show significant homology with known human DNA sequences. Interestingly, a gene related to cancer processes, the pim-1 oncogene, is placed neighbouring to this region on chromosome 6. Survival studies revealed that disease-free interval of NSCLC patients was shorter in patients bearing the amplified sequence (p = 0.05 by the Breslow test). Our findings suggest that the amplified sequence located on chromosome 6 might be relevant in the pathogenesis of human NSCLC. Int. J. Cancer (Pred. Oncol.), 84:344-349, 1999.

Animals↗
PubMed1999

Use of possible synergistic expression of p53 and p185 as a prognostic tool for stage I non-small-cell lung cancer.

The possible interaction between the quantified overexpression of the oncoproteins p53 and p185 was evaluated. These proteins have already been independently defined as prognostic factors in non-small-cell lung cancer (NSCLC). p53 and p185 levels were determined in stage I patients (n = 40) from a sample of 102 NSCLC sufferers who underwent surgery for precocious disease during the period October 1991 to June 1994. The resected tumors were histologically classified and included 15 adenocarcinomas (37.5%), 1 large-cell carcinoma (2.5%), and 24 epidermoid (60%) carcinomas. The p53 concentration of tumor specimens was determined by luminescence immunoanalysis and was defined as positive if it was above the minimum value detectable by the method (0.01 ng/mg). The p185 protein was quantified by enzyme-linked immunoassay, and the 80th percentile of the frequency distribution was used as the reference cutoff value (348.8 U/mg). Survival and disease-free-survival (DFS) rates were estimated at 24 months after intervention. There were no significant differences in survival or DFS of patients with adenocarcinoma-type tumors for subjects with independent p185 values < 348.8 U/mg and those showing values >/= 348.8 U/mg. Neither were there differences observed between patients with positive and negative p53 values. In patients with epidermoid-type tumors the cumulative survival was significantly higher in p53-negative than in p53-positive patients (p = 0.03) and was also higher in patients with p185 levels < 348.8 U/mg than in those with values >/= 348.8 U/mg (p = 0.00001). These patients showed no significant differences with respect to recurrence rate. The possible synergistic behavior of p53 and p185 levels as a prognostic factor was evaluated in patients with epidermoid-type tumors. p53-negative and p53-positive patients were grouped according to a p185 level of less than or more than 348.8 U/mg. Significant differences were seen in both survival rates and DFS between groups. Individual analysis of relative risks showed an increased risk of death and greater recurrence rate in patients with p185 levels >/= 348.8 U/mg and a greater recurrence rate in patients with p53-positive values. Multivariate analysis established that the multiplicative, synergistic, prognostic effect of p53 and p185 was not significant. The existence of a significant, synergistic, prognostic effect of the p185 and p53 proteins in NSCLC could not be proven. However, a greater prognostic potential of the quantified overexpression of p185 with respect to that of p53 was established. An additive effect in the prognostic potential of both proteins was also observed (stratified analysis).

Adult↗
PubMed1999

Differential prognosis of replication error phenotype and loss of heterozygosity in sporadic colorectal cancer.

Several distinct genetic alterations have been associated with colorectal tumorigenesis. This study investigated the frequency of microsatellite instability, also known as replication error (RER), and loss of heterozygosity (LOH) at six chromosome regions in sporadic colorectal cancer (CRC). Eighty-six tumour and paired normal mucosa samples were included in the study. A polymerase chain reaction (PCR)-based technique was performed to analyse six (CA)n dinucleotide repeats located near or within regions containing important genes implicated in the complex process of colorectal tumorigenesis (chromosomes 2p, 3p, 5q, 11p, 17p and 18q). Overall, LOH frequency was higher in RER-tumours (25/46, 54.3%) compared with RER+ tumours (9/40, 22.5) (P = 0.04). To investigate prognostic implications, survival analysis was performed for 66 patients. Compared with RER- tumours, patients with RER+ tumours at 2p, 3p, 5q, 11p or 18q were found to have an improved prognosis (overall survival, P = 0.02 and disease-free survival (DFS) P = 0.005) this variable being an independent prognostic factor by multivariate analysis (P = 0.001). Overall survival of patients whose tumours were LOH+ was significantly shorter compared with those without LOH (overall survival, P = 0.008 and DFS, P = 0.01). Thus, tumours displaying RER+ and LOH+ phenotype, as established by microsatellite analysis, show a differential prognosis. These data indicate that this may be a useful tool for the identification of patients at different risks affected by CRC.

Aged↗
PubMed1999

Multiple solitary leiomyomata of the esophagus.

The present report communicates a case of multiple solitary leiomyomata of the esophagus. This is an uncommon condition in which multiple, non-confluent, benign esophageal tumors arise in the same patient. The ideal treatment is enucleation of the lesions, but when these are--as in the case reported--huge and annular, or affect the gastroesophageal junction, resection of the gullet must be performed.

Adult↗
PubMed1999

Two-field radical lymphadenectomy in the treatment of esophageal carcinoma.

This paper retrospectively compares post-operative complications, mortality and long-term survival of patients with esophageal carcinoma who were treated with standard esophagectomy or with extended two-field lymph node clearance. Fifty-seven patients with resectable esophageal carcinoma were included in the study. Twenty-eight patients were submitted to a radical two-field esophagectomy and lymphadenectomy, while the remaining 29 were submitted to a standard, more conservative, esophagectomy performed mostly through a transhiatal route. The two groups of patients were similar in all clinical, laboratory and pathologic features. There was a significant lower anastomotic leakage rate in the group of patients submitted to a radical lymph node resection; post-operative respiratory complication rate and mortality were similar in both groups. The overall 5-year survival was 20%. When lymph node resection was performed, the 5-year survival rate rose to 36%; it was 44% when nodal involvement was negative and 19% for N1 patients; when standard esophagectomy was the procedure, these figures were 9% (p < 0.05), and 6% respectively.

Adenocarcinoma↗
PubMed1998

p53 exon 7 mutations as a predictor of poor prognosis in patients with colorectal cancer.

We have studied 61 resected colorectal adenocarcinomas in order to investigate p53 mutations as a prognostic factor for this pathology. Mutations in exons 5-9 of the p53 gene were analyzed by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique followed by sequencing. Our data indicate that p53 exon 7 mutations were prevalent in the latest stages of colorectal carcinogenesis and patients bearing this alteration had the worst prognosis. Therefore, according to our results, mutations affecting exon 7 of the p53 gene could be considered as a useful marker of biological aggressiveness for colorectal cancer.

Aged↗
PubMed1998

Prognostic value of genomic damage in non-small-cell lung cancer.

Genomic alterations have been analysed in 65 non-small-cell lung cancer (NSCLC) tissue samples by using the arbitrarily primed polymerase chain reaction (AP-PCR), which is a PCR-based genomic fingerprinting. We have shown that AP-PCR may be applied as a useful and feasible practical method for detection of the genomic alterations that accompany malignancy in NSCLC. Genomic changes detected by us consisted of: allelic losses or gains in anonymous DNA sequences, homozygously deleted DNA sequences and polymorphic DNA sequences. According to these genomic changes, lung tumours evaluated in the present study have been scored into three groups: low, moderate and high genomic damage tumours. The aim of this study was to investigate the effect of genomic damage on patient survival. Survival analysis was carried out in 51 NSCLC patients. Our results revealed that high genomic damage patients showed a poorer prognosis than those with low or moderate genomic damage (P = 0.038). Multivariate Cox regression analysis showed that patients with higher genomic alterations displayed an adjusted-by-stage risk ratio 4.26 times higher than the remaining patients (95% CI = 1.03-17.54). We can conclude that genomic damage has an independent prognostic value of poor clinical evolution in NSCLC.

Adult↗
PubMed1998

Genetic abnormalities and microsatellite instability in colorectal cancer.

Our purpose was to investigate different genetic abnormalities, such as K-ras mutations, p53 alterations, and c-myc RNA overexpression, as well as microsatellite instability in 63 colorectal tumors obtained from patients that had undergone surgery. K-ras point mutations were analyzed by PCR-RFLP technique, followed by sequencing; p53 protein accumulation by immunohistochemistry; p53 gene mutations in exons 5-9 were studied by the SSCP and sequencing techniques, and c-myc overexpression by Northern blot. Microsatellite instability was performed at chromosomes 2p, 3p, and 11p by a PCR-based technique. Our data indicate a trend toward a poorer prognosis in patients who had K-ras transversions; besides, we have obtained a prevalence of c-myc RNA overexpression and p53 exon 7 mutations in the latest stages of tumor progression. In conclusion, our findings suggest that the recognition of molecular abnormalities might be used in colorectal cancer as a prognostic indicator or to determine the metastatic potential of colorectal adenocarcinomas.

Aged↗
PubMed1995

[Surgical treatment of pulmonary aspergilloma].

Pulmonary aspergilloma can now be classified as an opportunistic disease given that Aspergillus tends to colonize preexisting cavities in the lung. Aspergilloma is the usual pleuropulmonary anatomical sign, hemoptysis is the most frequent symptom and a chest film is the simplest diagnostic tool. The advisability of surgery is disputed, particularly in asymptomatic patients and/or those at high surgical risk. We describe 14 patients who underwent surgery in our department, evaluating aspects of their clinical signs, diagnosis, attitude toward treatment and the course of their disease. We believe that for patients with symptomatic pulmonary aspergilloma, the treatment of choice is surgery, preferably lung resection. All patients who do not present contraindications for general surgery can be considered operable.

Adult↗
PubMed1994

Quantitative analysis of carcinoembryonic antigen, squamous cell carcinoma antigen, CA 125, and CA 50 cytosolic content in non-small cell lung cancer.

BACKGROUND: The cytosolic content of carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC), CA 125, and CA 50 antigens in non-small cell lung cancer (NSCLC) is analyzed in this study. The aim was to ascertain the relationship between tumor marker content and the clinicopathologic aspects of this neoplasm. METHODS: Lung tissue samples were obtained at the time of surgery from 75 patients with NSCLC patients (samples of tumor and unaffected tissue) and 29 subjects with idiopathic pneumothorax. All determinations were performed on cytosols obtained from lung specimens. CEA and CA 125 were determined by enzyme immunoassay, SCC antigen by radioimmunoassay, and CA 50 by fluoroimmunoassay. Tumor marker content was analyzed by TNM stage, histologic type, tumor grade, and number of atypias. RESULTS: The concentration of the four markers was significantly higher in cytosol obtained from neoplastic tissue. Frequency of elevated levels of CEA was higher in adenocarcinoma (87% cases expressing high levels of the marker), SCC antigen in epidermoid carcinoma (65% expressing high levels), and CA 125 in large cell carcinomas (100% expressing high levels). No association was found between TNM stage and cytosol concentration for any of the four markers. CEA exhibited significantly greater concentration in well differentiated tumors, whereas this was true of CA 125 in poorly differentiated tumors. CA 125 content was higher in tumors with more atypia. CONCLUSIONS: Cytosolic quantification of tumor markers may be an adjuvant mechanism to evaluate histologic subtypes of non-small cell lung cancer and identification of tumors with poorly differentiated features.

Adenocarcinoma↗