Ignacio Álvarez

Prognostic factors in paranasal sinus cancer

PURPOSE This study was designed to evaluate the influence of several different prognostic factors in determining both local recurrence rates and survival in patients treated for carcinoma of the paranasal sinuses. MATERIALS AND METHODS A retrospective study of patients treated between January, 1975 and December, 1991 was undertaken. Hospital charts were reviewed collecting demographic, clinical, and radiographic findings, which were correlated with treatment and subsequent follow-up. RESULTS Carcinoma of the paranasal sinuses was identified in 129 patients. This included 95 men and 34 women with an average of 59 years. The ethmoid sinus was primarily involved in 50 patients, the maxillary sinus and 49, the nasal sinus and 25, sphenoid sinus in three in the frontal sinus and two patients. Advanced stage (T3/T4) was diagnosed in 60% of patients at presentation. The most commonly encountered histologies were squamous-cell carcinoma and adenocarcinoma. The most accurate predictors of poor prognosis were advanced T stage and involvement of the anterior skill base. Involvement of the posterior wall of the maxillary sinus, infratemporal fossa, and erosion of the orbital wall was not associated with the worst prognosis. CONCLUSION In spite of advances in imaging technique and surgical therapy, the primary cause of death is inability to control local disease. Diagnosis at an earlier stage is associated with improved outcome.

Amplification of ERBB oncogenes in squamous cell carcinomas of the head and neck

The activation of ERBB oncogenes has been described in various human tumours, including squamous cell carcinomas of the head and neck (SCCHN), and, in some of them, it has been correlated with a poor prognosis. Tissue samples from 59 patients with SCCHN were studied. After DNA extraction, the ERBB1, ERBB2 and ERBB3 copy number in tumour samples was estimated with the polymerase chain reaction (PCR) method. The PCR products were analysed by agarose gel electrophoresis and quantified by image analysis techniques. 9 (15%) cases presented with ERBB1 amplification, which was correlated with lymph node involvement (P = 0.04), poorly differentiated tumours (P = 0.03) and a hypopharyngeal primary site (P = 0.035). No correlation among amplification status, recurrence, metastases and survival was observed, although this may be due to the small number of patients in the amplified group. None of the 59 cases presented amplification of ERBB2 and ERBB3 oncogenes.

Variability of Genetic Alterations in Different Sites of Head and Neck Cancer

Objective Tumors arising from different sites of the head and neck area have different clinical behavior. However, most of the studies on genetic alterations in head and neck squamous cell carcinomas do not make a distinction between the sites within this area. The objective of this study is to compare the genetic alterations in three different sites of the head and neck (larynx, oropharynx, and hypopharynx).

Genetic alterations in squamous cell carcinomas of the hypopharynx with correlations to clinicopathological features

The objective of this study is to describe the molecular alterations in carcinomas in one specific location of the head and neck, the hypopharynx. Thirty-seven hypopharyngeal squamous cell carcinomas were studied. The DNA from tumour and healthy tissue was evaluated for amplification of the 11q13 region and of the MYC and ERBB1 oncogenes, for integration of the Human Papillomavirus (HPV), and for loss of heterozygosity (LOH) at p53 and NAT2 loci. The most common alteration was the amplification of the 11q13 region (78% of the cases), followed by LOH at p53 locus (70%). MYC amplification was found in 19% of the cases, ERBB1 amplification in 29%, LOH at NAT2 locus in 25%, and integration of the HPV in 29%. 11q13 amplification was related with nodal metastases and higher tumour recurrence rates. These findings confirm that 11q13 amplification is one of the most frequent genetic alterations in hypopharyngeal squamous cell carcinomas, and that it may have prognostic significance in these tumours.

On-line metrology with conoscopic holography: beyond triangulation.

On-line non-contact surface inspection with high precision is still an open problem. Laser triangulation techniques are the most common solution for this kind of systems, but there exist fundamental limitations to their applicability when high precisions, long standoffs or large apertures are needed, and when there are difficult operating conditions. Other methods are, in general, not applicable in hostile environments or inadequate for on-line measurement. In this paper we review the latest research in Conoscopic Holography, an interferometric technique that has been applied successfully in this kind of applications, ranging from submicrometric roughness measurements, to long standoff sensors for surface defect detection in steel at high temperatures.

Using polymerase chain reaction to human papillomavirus in oral and pharyngolaryngeal carcinomas

Abstract Purpose: Increasingly, evidence has shown that human papillomavirus (HPV) plays a role in the induction of certain carcinomas. The presence of HPV sequences in 56 previously untreated oral and pharyngolaryngeal carcinomas was examined by the polymerase chain reaction (PCR). Materials and Methods: After DNA extraction, samples underwent 40 replication cycles with specific oligonucleotide primers corresponding to sequences from the E6 open-reading frame of HPV-6b, HPV-16, and HPV-18. To determine the E6 genomic integration, positive samples were processed with specific primers for the corresponding HPV L1 genes. Genomic HPV DNA cloned into PBR 322 was used as positive control. Results: HPV E6 DNA of the 6b and 16 types was detected in 14 patients (25%). The L1 gene was not present. Conclusion: Detected HPV E6 DNA might be integrated into the cell genome in the positive cases as indicated by the absence of the L1 gene-coding for the viral capside. Histological and clinical parameters, such as tumor location, degree of differentiation, stage, recurrence, and survival rates, were unrelated to the presence of HPV.

Conoscopic holography-based long-standoff profilometer for surface inspection in adverse environment

One of the more challenging applications of optical metrology is real-time dimensional control and surface inspection in industrial ap- plications, where strong requirements of cost, setup, and applicability in adverse environments greatly limit the number of applicable technolo- gies. This work shows an optic profilometer developed specifically for this purpose, the algorithms developed for efficient and accurate dis- tance map calculation, and an example of its use in a harsh steelmaking environment. This device, based on conoscopic holography, is able to obtain a distance profile of a target in a single shot, works at long dis- tance standoff 700 to 1200 mm, and still keeps good resolution under 0.2 mm with a very easy and reliable setup. The second part of the work focuses on a real example of this technology applied in an on-line in- spection system in steel continuous casting funded by the European Coal and Steel Community, and which is currently working in the Aceralia LDA steelmaking factory in Asturias Spain. The system is placed in the process line and performs on-line detection of surface defects over hot steel slabs above 800°C in the inspection point from a distance of 1200 mm. 100% of the production can be inspected without interfering with the process and without adding any delay.

Industrial online surface defects detection in continuous casting hot slabs

Early surface defects inspection in hot steel products is a difficult task, but can help to reduce significantly production costs. This is the case of steel slabs when they are produced in the continuous casting line. Conoscopic holography phase-based long stand-off profilometers have shown to be a great tool for this kind of inspection, and a breakthrough system based on them is being used for more than 2 years in production conditions with high reliability and economical impact. This paper presents the results of this system and the challenges it has overcome: hot material up to 900°C, dust, scale over the inspected surface.

Common-path two-wavelength interferometer with submicron precision for profile measurements in on-line applications

We propose a common-path two-wavelength interferometric system based on a single optical element, a Savart plate, that is able to obtain single-shot profile measurements with submicron precision from safe working distances (beyond 100 mm). These characteristics make this sensor ideal for surface inspection in on-line applications. For the illumination branch, two lasers with close wavelengths are combined and then passed through a rotating holographic diffuser for drastic speckle reduction. In the acquisition branch, the interferometric signals of both wavelengths are captured simultaneously by a camera, and their phase signals are combined to extend the measurement range.

On-line submicron profile measurements from safe distances with conoscopic holography: feasibility and potential problems

On-line noncontact surface inspection with high precision is still an open problem. Usual methods are, in general, not applicable in hostile environments or not adequate for on-line measurement, as they are either slow in nature or need to work from very short, unsafe distances, providing small depths of field and apertures. The ongoing work toward the development of a noncontact optical profile measuring sensor that could be used for submicron measurements in on-line applications is presented here. Our approach is based on conoscopic holography and triangulation, and uses a very simple method for removing speckle noise, which is key for obtaining high precisions from safe distances (several centimeters).