Occupational exposure to diesel exhausts and risk for lung cancer in a population-based case-control study in Italy.

BACKGROUND: We studied the effect of exposure to diesel exhausts on lung cancer risk in a population-based case-control study in the city of Turin, Italy. PATIENTS AND METHODS: Information on occupational histories of 595 incident lung cancer cases diagnosed in 1991-1992 and 845 population controls was obtained. During the interviews, diesel job-specific modules (D-JSMs) were administered whenever subjects had worked in occupations included in the following nine categories: railroad workers, miners, professional drivers and transport conductors, heavy-machine operators, mechanics and testers, filling station attendants, motor-vehicle park attendants, transport equipment operators, and occupations carried out in/near urban roads. All D-JSMs were evaluated for probability, intensity and frequency of exposure. RESULTS: The odds ratio for ever exposure to diesel exhausts was 1.04 (95% confidence interval 0.79-1.37), after adjusting for age, sex, smoking and having worked in occupations entailing exposure to known lung carcinogens. No association was found with intensity, probability and duration of exposure. CONCLUSIONS: Although misclassification of the exposure may have contributed to the negative results, we did not find an association between occupational exposure to diesel exhausts and lung cancer risk.

Tumores estromales gastrointestinales / Stromal tumors gastrointestinal

Introducción: los tumores estromales gastrointestinales (GISTs)son un grupo eterogéneo de neoplasias mesenquimáticas, controvertidas para muchos en cuanto a morfología, criterios diagnósticos y comportamiento. Datos clínicos: se revisaron todos los tumores mesenquimáticos gastrointestinales de archivo del período 1992-2002. Se hallaron 7 casos de GISTs (25 por ciento de los tumores mesenquimáticos): 4 mujeres y 3 hombres, de 53 a 89 años; 5 fueron de estámago, 1 de intestino delgado y 1 de trascavidad de los epiplones. Métodos disgnósticos: el material se procesó según técnicas de rutina y se coloreó con H.E. Se efectuó IHQ para Actina Músculo Liso (AML), Desmina, S 100, CD 117. Hallazgo macroscópicos: todos los casos correspondieron a piezas quirúrgicas (gastrectomía, resección segmentaria intestinal o tumorectomía). El tamaño tumoral osciló entre 4 y 25 cm. Hallazgos microscópicos: consistieron en proliferaciones fusiformes, con grado variable de celularidad, atipía y actividad mitótica (AM)...

Tumores estromales gastrointestinales / Stromal tumors gastrointestinal

Introducción: los tumores estromales gastrointestinales (GISTs)son un grupo eterogéneo de neoplasias mesenquimáticas, controvertidas para muchos en cuanto a morfología, criterios diagnósticos y comportamiento. Datos clínicos: se revisaron todos los tumores mesenquimáticos gastrointestinales de archivo del período 1992-2002. Se hallaron 7 casos de GISTs (25 por ciento de los tumores mesenquimáticos): 4 mujeres y 3 hombres, de 53 a 89 años; 5 fueron de estámago, 1 de intestino delgado y 1 de trascavidad de los epiplones. Métodos disgnósticos: el material se procesó según técnicas de rutina y se coloreó con H.E. Se efectuó IHQ para Actina Músculo Liso (AML), Desmina, S 100, CD 117. Hallazgo macroscópicos: todos los casos correspondieron a piezas quirúrgicas (gastrectomía, resección segmentaria intestinal o tumorectomía). El tamaño tumoral osciló entre 4 y 25 cm. Hallazgos microscópicos: consistieron en proliferaciones fusiformes, con grado variable de celularidad, atipía y actividad mitótica (AM)...(AU)

[Granular cell tumor of the esophagus. Morphological and immunohistochemical study]. / Tumor de células granulares del esófago. Estudio morfológico e inmunohistoquímico.

Granular cell tumor or Abrikosoff's tumor is an infrequent and usually benign neoplasm which is found predominantly in the head and neck region, especially in the tongue. Its esophageal location is unusual, where most of them present as small, well circumscribed lesions which follow a benign course. Because of its low incidence in this site (less than 200 cases having been reported until 1993), we report two cases of esophageal granular cell tumors, both of them in male patients. CASE 1: A 34 year old patient who presented with epigastralgia, heartburn and abdominal distention. He was treated endoscopically because he had a firm new growth in the lower third of the esophagus measuring 1 cm in diameter. CASE 2: A 50 year old patient who presented with digestive tract haemorrhage (hematemesis and melena) 5 cm above the cardias a submucosal polyp was found of 0.8 cm in its largest diameter. MICROSCOPY: Both cases showed a subepithelially located new growth, composed of polygonal cells with eosinophilic granular cytoplasm, small rounded nuclei, and conspicuous intracytoplasmatic positivity for S100 protein. With these elements we reached the diagnosis of granular cell tumor. The bibliography is reviewed and an update is made of its histopathologic characteristics in addition to histogenetic and clinical considerations.

[Activation of K-ras and c-erbB-2 protooncogenes in human colonic adenocarcinomas]. / Activación de los protooncogenes K-ras y c-erbB-2 en adenocarcinomas colónicos humanos.

Although data on genetic alterations leading to development of colorectal cancer are abundant, no specific genetic alteration has been demonstrated for each class of tumor. The colorectal cancer phenotype is originated from an accumulation of different genetic alterations. The nature of these alterations, their order of appearance, and their associations vary greatly from one tumor to another, suggesting that the concept of a unique model of carcinogenesis is not applicable to these tumors. The aim of the present work was to study the association between K-ras and c-erbB-2 mutations and different clinicopathological variables in fifty-four samples from adenocarcinomas of the colon. The detection of K-ras activation was performed by specific enriched PCR. The genomic differential polymerase chain reaction with the single copy reference gene was employed for the detection of c-erbB-2 gene amplification. K-ras mutations were detected in 16 cases (29.63%) and c-erbB-2 amplifications in 1 sample (1.85%). Statistical analysis showed a significant association between K-ras codon 12 mutation frequency and Duke's stage B (p < 0.05). On the other hand, there was no association in relation to the other studied parameters. These results could indicate the occurrence of K-ras activation in early stages of the disease.

Activación de los protooncogenes K-ras y c-erbB-2 en adenocarcinomas colónicos humanos. / [Activation of K-ras and c-erbB-2 protooncogenes in human colonic adenocarcinomas]

Although data on genetic alterations leading to development of colorectal cancer are abundant, no specific genetic alteration has been demonstrated for each class of tumor. The colorectal cancer phenotype is originated from an accumulation of different genetic alterations. The nature of these alterations, their order of appearance, and their associations vary greatly from one tumor to another, suggesting that the concept of a unique model of carcinogenesis is not applicable to these tumors. The aim of the present work was to study the association between K-ras and c-erbB-2 mutations and different clinicopathological variables in fifty-four samples from adenocarcinomas of the colon. The detection of K-ras activation was performed by specific enriched PCR. The genomic differential polymerase chain reaction with the single copy reference gene was employed for the detection of c-erbB-2 gene amplification. K-ras mutations were detected in 16 cases (29.63

) and c-erbB-2 amplifications in 1 sample (1.85

). Statistical analysis showed a significant association between K-ras codon 12 mutation frequency and Dukes stage B (p < 0.05). On the other hand, there was no association in relation to the other studied parameters. These results could indicate the occurrence of K-ras activation in early stages of the disease.

Tumor de células granulares del esófago. Estudio morfológico e inmunohistoquímico. / [Granular cell tumor of the esophagus. Morphological and immunohistochemical study]

Granular cell tumor or Abrikosoffs tumor is an infrequent and usually benign neoplasm which is found predominantly in the head and neck region, especially in the tongue. Its esophageal location is unusual, where most of them present as small, well circumscribed lesions which follow a benign course. Because of its low incidence in this site (less than 200 cases having been reported until 1993), we report two cases of esophageal granular cell tumors, both of them in male patients. CASE 1: A 34 year old patient who presented with epigastralgia, heartburn and abdominal distention. He was treated endoscopically because he had a firm new growth in the lower third of the esophagus measuring 1 cm in diameter. CASE 2: A 50 year old patient who presented with digestive tract haemorrhage (hematemesis and melena) 5 cm above the cardias a submucosal polyp was found of 0.8 cm in its largest diameter. MICROSCOPY: Both cases showed a subepithelially located new growth, composed of polygonal cells with eosinophilic granular cytoplasm, small rounded nuclei, and conspicuous intracytoplasmatic positivity for S100 protein. With these elements we reached the diagnosis of granular cell tumor. The bibliography is reviewed and an update is made of its histopathologic characteristics in addition to histogenetic and clinical considerations.

[Systematic study of gastrectomy specimens for cancer, in search of synchronous carcinomas]. / Estudio sistematico de piezas de gastrectomia por cáncer en búsqueda de carcinomas sincrónicos.

Multiple carcinomas were searched in 50 successive gastrectomies, 17 females (34%) 33 males (66%) from 40 to 83 years old. Macroscopic handling of the specimens included pinning on a board, fresh, half-fixed and completely fixed examination, not only by naked eye but also through a magnifying glass. The stomach were totally studied, according to Japanese method. A satisfactory slide was obtained from each block, stained with H.E. and examined by each of the authors. Synchronous tumors were found in 4 cases (8%), 3 males and one female. Compared to the main lesion, two cases showed a proximal tumor, one case showed a distal tumor, and the last one showed two tumors, one of them proximal and the other distal. Three tumors were macroscopically and two were microscopically detected. Two of them coexisted with advanced carcinoma and three with early carcinoma. Four of them were located in mucosa with intestinal metaplasia. Histologically, four cases belong to the same type of the original tumor, and one of them did not coincide. We conclude that stomachs resected for cancer must be thoroughly and methodically studied before and after fixation. We suggest that resection must include the whole mucosa with intestinal metaplasia, in order to avoid leaving a synchronous tumor in the gastric stump.

Mosquito larvae extract induces mitotic rate alterations of mice tongue keratinocytes along a circadian rhythm period.

It has been demonstrated that the crude extract of mosquito larvae alters the mitotic rate of several mouse cell populations of young growing mice (25 +/- 1 days old). Furthermore, the dialysed fraction of the extract inhibited proliferation of hepatocytes from hepatectomized adult male mice (90 days old). Sampling during the period between 16 and 24 h after treatment (when mitotic peak normally occurs) shows an inhibiting effect on the G1/S interphase, whereas evaluation during the dark phase of the circadian rhythm period (i.e. 4 to 12 h after treatment) shows an increment of the mitotic rates suggesting a probable effect at G2/M restriction point. In the present paper we report the effect of the mosquito larvae crude extract on the proliferative activity of tongue keratinocytes along a circadian rhythm period. Treatments were intraperitoneally applied at 16/00 Time of Day/Time post Injection and mice were killed at 00/08, 04/12, 08/16, 12/20 and 16/24 TD/TPI. As other cell populations previously analysed, the mitotic rate of tongue keratinocytes of extract receivers was significantly increased during night (when S phase normally occurs) and inhibited during the 08/16 to 16/24 period.

Solid cell nests of the thyroid gland. Optic and immunohistochemical study at autopsies.

In order to establish the prevalence of solid cell nests (SCN) in adult thyroids, we studied 100 consecutive glands at necropsy. These were serially sectioned and stained with routine and immunoperoxidase techniques in order to detect calcitonin, carcinoembryonic antigen, thyroglobulin and keratin. SCN may be considered as normal thyroid gland components, and they share with C cells a common origin in the ultimobranchial body.

[Early flat colorectal cancer]. / Cáncer recto colónico temprano plano.

We report three cases of flat early colorectal carcinoma which were detected during the examination of 51 surgical specimens of colorectal resection. Two of them were endoscopically diagnosed, but the smallest one was not seen in the luminal instrumental examination. From the bibliographic analysis and our own experience we deduce the importance of flat lesions in the development of early colorectal carcinoma, either originated from pre-existent adenoma or de novo. Flat variants of adenoma, and presumably flush or depressed ones, must be considered as important factors in the early sequence adenoma-cancer. An appropriate endoscopic equipment with employment of additional staining techniques (such as carmine indigo and methylene blue) and the correct investigation during inflation-deflation procedures facilitates the identification of small lesions, their eradication and prevention from advanced forms of colorectal carcinoma.

Cáncer recto colónico temprano plano. / [Early flat colorectal cancer]

We report three cases of flat early colorectal carcinoma which were detected during the examination of 51 surgical specimens of colorectal resection. Two of them were endoscopically diagnosed, but the smallest one was not seen in the luminal instrumental examination. From the bibliographic analysis and our own experience we deduce the importance of flat lesions in the development of early colorectal carcinoma, either originated from pre-existent adenoma or de novo. Flat variants of adenoma, and presumably flush or depressed ones, must be considered as important factors in the early sequence adenoma-cancer. An appropriate endoscopic equipment with employment of additional staining techniques (such as carmine indigo and methylene blue) and the correct investigation during inflation-deflation procedures facilitates the identification of small lesions, their eradication and prevention from advanced forms of colorectal carcinoma.

Occult papillary thyroid carcinoma at autopsy in La Plata, Argentina.

Although clinically evident thyroid carcinoma is not a frequent neoplasm (incidence 2.7 per 100,000 persons in La Plata, Argentina), occult carcinomas are present in a high proportion of the population, but there are marked differences along geographical lines. The purpose of the present study is to establish the prevalence of occult papillary thyroid carcinoma (OPC) in La Plata. Thyroid glands obtained from 100 consecutive adult necropsies were examined. The material was fixed in buffered formaldehyde at 4 degrees C, serially sectioned at 2 mm intervals, and routinely processed. Eleven thyroid glands contained OPC, corresponding in three cases to multiple lesions. Eight carcinomas were found in 59 men (13.6%) and three in 41 women (7.3%). The ages ranged from 26 to 78 years. The neoplasms varied in size from microscopic foci to 9 mm in diameter. The prevalence rate of OPC in the present study is lower than that found in Finland, Japan, and the US, and higher than for the rest of the series recorded.