Regression of duodenal gastric metaplasia in Helicobacter pylori positive patients with duodenal ulcer disease

BACKGROUND

It is unclear whether the extent of duodenal gastric metaplasia is due to Helicobacter pylori and/or acid.

AIMS

To investigate the role of Helicobacter pylori eradication in the regression of duodenal gastric metaplasia in patients with duodenal ulcer maintained in acid suppression conditions.

METHODS

. Duodenal (anterior, superior inferior walls of first part of duodenum) and gastric antrum biopsies were obtained from 44 Helicobacter pylori positive duodenal ulcer patients. Helicobacter pylori infection was diagnosed by rapid urease test, histology and 13C-Urea Breath Test. Patients were treated with 20 mg omeprazole tid associated with 250 mg clarithromycin and 500 mg amoxycillin four times daily for 10 days and maintained with 20 mg omeprazole daily for 18 weeks. Control endoscopies were performed at 6 and 18 weeks after beginning treatment.

RESULTS

Duodenal gastric metaplasia regression was observed in all (32/32) patients in whom Helicobacter pylori was eradicated, but in only 3 out of 6 patients in whom eradication was not achieved (p<0. 001).

CONCLUSIONS

. The present results suggest that Helicobacter pylori eradication associated with prolonged acid suppression may represent a good therapeutic strategy to achieve duodenal gastric metaplasia regression and highlight the combined role of acid and Helicobacter pylori in the pathogenesis of duodenal gastric metaplasia.

Impairment of gastric secretion modulation in duodenal ulcer and in long-term PPI treatment: quantitative morphologic findings and pathophysiologic implications

Helicobacter pylori affects gastric secretion. This functional effect might have a morphometric counterpart. Therefore, the gastric cell secretory compartment was morphometrically assessed in different pathophysiologic conditions related to Helicobacter pylori infection. Nineteen Helicobacter pylori-positive nonduodenal ulcer subjects, 15 omeprazole chronically treated subjects, and 19 duodenal ulcer patients were studied against 19 controls. Somatostatin, gastrin, enterochromaffin-like, and parietal cell density was assessed in gastric biopsies. No differences in any cell type density were found between Helicobacter pylori-positive nonduodenal ulcer subjects and controls. On the contrary, differences were significant when comparing omeprazole and duodenal ulcer patients to controls (higher density of gastrin, enterochromaffin-like, and parietal cells, lower density of somatostatin cells). In duodenal ulcer a reversion to control values followed Helicobacter pylori eradication and ulcer healing. A direct linear correlation between enterochromaffin-like, gastrin, and parietal cell density was demonstrated. An almost complete map of mucosal cells involved in gastric secretion is provided by this study. The cell density pattern, identical to the omeprazole group, points to an impaired feedback control of secretion in duodenal ulcer. The reversion to control values after Helicobacter pylori eradication and ulcer healing demonstrates the pathogenetic role of Helicobacter pylori-host interaction in these changes.

Long-term prognosis of gastric cancer in a European country: a population-based study in Florence (Italy). 10-year survival of cases diagnosed in 1985-1987

This paper analysed, in a population-based series of 1976 gastric cancers diagnosed in Florence (Italy), from 1985 to 1987, the relationship between prognostic variables (demographic, clinical and pathological) and 10-year survival rates. Gastric cancer was mostly detected in elderly patients (mean age: 70.5 years) and at advanced stages (i.e. approximately 50% of the patients could not undergo radical surgery). Ten-year observed survival was 12.1% (95% confidence interval (CI): 10.6-13.6%) for the whole series and 20.8% (95% CI: 18.3-23.3%) for resected cases; relative survival was, respectively, 20.9% (95% CI: 18.4-23.4%) and 32.0% (95% CI: 28.1-35.9%). Ten-year relative survival was 86% for stage IA (95% CI: 73-99%) and 67% for stage IB (95% CI: 52-82%). Multivariate analysis showed a significantly better prognosis in females and a significantly worse prognosis in patients aged 65 years or more (reference: < or = 59 years). In addition, an independent prognostic effect was observed for pT in the resected cases (reference: pT3; pT1: RR = 0.47, 95% CI: 0.34-0.64; pT2 = 0.71, 95% CI: 0.58-0.87; pT4: RR = 2.02, 95% CI: 1.49-2.75), pN (reference: pN0; pN1: RR = 2.13, 95% CI: 1.70-2.68; pN2-3: RR = 3.14, 95% CI: 2.42-4.07; pN+ no. nodes involved unspecified: RR = 4.26, 95% CI: 3.11-5.83) and surgical margin involvement (reference: not involved; involved: RR = 1.36, 95% CI: 1.08-1.72). In addition, the stage, after adjustment for age, gender and surgical margin involvement, showed a strong independent prognostic value (reference: stage II; IA: RR=0.37, 95% CI: 0.25-0.57; IB: RR=0.70, 95% CI: 0.50-0.98; IIIA: RR = 1.80, 95% CI: 1.40-2.33; IIIB: RR = 2.82, 95% CI: 2.14-3.72; IV: RR = 3.29, 95% CI: 2.36-4.59). In conclusion, on the basis of a large population-based series, our results confirm the prognostic effect on long-term gastric cancer survival of pathological and demographic variables. In addition, the study shows that Italy had a relatively good, long-term survival when diagnosis was performed at early stages. However, only a few cases were diagnosed at stages when cure by radical surgery is more likely (i.e. stage I accounted for approximately 20% of the resected cases and less than 10% of all incident cases).

Expression of nm23 gene in gastric cancer is associated with a poor 5-year survival

The nm23 gene is thought to play a role as an inhibitor of metastatic progression in several human cancers and its down-regulation has been associated with increased metastasis and reduced survival in some studies, though not in others. To better investigate the role of nm23 in gastric cancer (GC), the expression and prognostic impact of this gene was examined in 107 radically operated GC patients in a high risk area. The expression of nm23 was determined immunohistochemically by using the rabbit antibody anti-human nm23 protein. The expression of nm23 was detected in 40.2% (n = 43) of 107 gastric tumours and correlated with a poorer clinical outcome. In a survival analysis at 5 years, patients with nm23-positive tumours had significantly worse prognosis than patients (n = 64) with nm23-negative tumours (p < 0.05). The prognostic significance of nm23 expression was confirmed by multivariate analysis including terms for tumour stage and lymph node involvement. Our results suggest that the expression of the nm23 gene in gastric carcinoma is significantly related to tumour progression and poor prognosis at 5 years.

Red meat, family history, and increased risk of gastric cancer with microsatellite instability

Microsatellite instability (MSI) occurs frequently in sporadic gastric cancer (GC) and may define a distinctive molecular pathway of carcinogenesis. We evaluated the role of dietary risk factors in GC according to MSI status. A large series of 382 GC cases and 561 controls were originally identified in a population-based case-control study carried out in the high-risk area around Florence, Italy; 126 GC patients were typed for MSI status. A MSI+ phenotype was detected in 43 of 126 cases (34.1%), whereas 83 cases were classified as MSI-. A multinomial logistic regression model was used to compare the two subgroups of GC classified according to MSI status in the same analysis, with all of the available population controls. A case-case approach was also used. The risk of MSI+ tumors was positively associated with high consumption of red meat and meat sauce and negatively associated with consumption of white meat. A positive association was also seen with total protein and nitrite intake, whereas no relation was found with micronutrient intake. Risk was especially high among subjects reporting both a positive GC family history and a high consumption of red meat (odds ratio, 25.7; 95% confidence interval, 6.4-102.8). For MSI- tumors, a significant protective effect was associated with frequent consumption of citrus and other fresh fruit, garlic, legumes, vegetables, and olive oil and with high intake of beta-carotene and other antioxidants and sugar, whereas positive associations were seen with protein and sodium intake. In summary, a specific dietary pattern emerged for MSI+ gastric tumors, suggesting that factors related to red meat consumption are involved in this pathway, particularly among individuals with a positive family history. In contrast, the risk of MSI- tumors was strongly reduced by the frequent consumption of fresh fruit and vegetables.

Gastric carcinomas of intestinal type concur with distant changes in the gastric mucosa. A multicenter study in the Atlantic basin

Population studies in the Pacific Basin showed that gastric carcinomas of intestinal type often concur with distant mucosal changes (DMCs). In the present work, the presence of DMCs was investigated in populations dwelling in the Atlantic Basin. A total of 1737 gastrectomy specimens were reviewed: 627 in New York, 435 in Reykjavik, 198 in Buenos Aires, 186 in Florence, 174 in London and the remaining 117 in Stockholm. A total of 17,282 sections were carefully scrutinized. The following DMCs were investigated: intramucosal glandular cysts, gastric cells with ciliated metaplasia, with large or small mucus negative vacuoles, and extensive intestinal metaplasia (IM). The highest frequencies of DMCs were found in Florence for specimens with intestinal type carcinoma: 41.3% had intramucosal cysts, 22.4% had cells with ciliated metaplasia, 12.9% cells with large vacuoles, and 50.9% had high IM. The highest frequency of gastric cells with small vacuoles was recorded in New York (9.1%), also in specimens with intestinal type carcinoma. Significantly lower DMCs percentages were found in specimens with carcinomas of diffuse type, and miscellaneous gastric diseases. The occurrence of DMCs was not influenced to a significant degree by the number of sections available per gastrectomy. Since environmental factors trigger the evolution of intestinal type carcinomas and as DMCs also occurred in specimens without carcinoma-although at a significantly lower rate--it is conceivable that DMCs are also evoked by environmental factors (before a gastric carcinoma ensues). DMCs were found in specimens having intestinal carcinomas either in the cardia, the corpus or the antrum. Thus, DMCs seem to provide the adequate "soil" for the development of gastric carcinomas of intestinal type, independently of the future localization of that tumor in the stomach.

Primary leiomyosarcoma of the pancreas: a case report and review of literature

Primary leiomyosarcoma of the pancreas is a rare tumor for which only 21 reports appear in the world literature. We describe an additional case of pancreatic leiomyosarcoma in a 76-year-old man, who complained of persistent high fever. Histologic examination revealed a pleomorphic spindle cell tumor. Reactivity for muscle-specific actin, alpha-smooth muscle actin, and basement membrane components, along with negative staining for epithelial and neural markers, were consistent with a smooth muscle sarcoma. The patient died of disease 1 year after complete surgical excision. This report highlights the need to use a complete antibody panel in order to accurately immunophenotype pleomorphic malignant tumors of the pancreas. A review of the cases compiled in the literature indicates that pancreatic leiomyosarcoma, like its counterpart arising in deep soft tissues, is an aggressive neoplasm characterized by short survival and a high rate of metastases.

Villous and serrated adenomatous growth bordering carcinomas in inflammatory bowel disease

The histologic phenotype of the dysplastic lesion juxtaposing colorectal carcinomas was assessed in 100 consecutive colectomy specimens: in 50 patients with inflammatory bowel disease (IBD) and in 50 controls (non-IBD patients). Adenomatous growths (AG) were regarded both Dysplasia Associated Lesion or Mass (DALM) and sporadic adenomas. AGs juxtaposing carcinomas were found in 76% (n = 38) of the IBD cases: 52.3% (20 out of 38) were villous, 28.9% (11 out of 38) serrated, 5.3% (2 out of 38) tubular and the remaining 13.2% (5 out of 38) were mixed AGs. Juxtaposing AGs (sporadic adenomas) were also found in 58% (n = 29) of the control cases: 51.7% (15 out of 29) were villous, 6.9% (2 out of 29) tubular, 3.4% (1 out of 9) serrated and the remaining 37.9% (11 out of 29) were mixed. The majority or 81.2% (31 out of 38) of the dysplastic lesions juxtaposing IBD carcinomas were villous or serrated AGs, but only 55.1% (16 out of 29) in control cases. Serrated AGs in particular accounted for nearly 29% of the non-invasive dysplastic lesions abutting IBD carcinomas but only for 3% in control specimens. It would appear that villous and serrated AGs are the most common non-invasive neoplastic lesions from which IBD carcinomas originate.

Dietary and familial determinants of 10-year survival among patients with gastric carcinoma

BACKGROUND

Although the role of diet in gastric carcinoma (GC) causation has been investigated extensively, its association with long term survival has never been explored in detail.

METHODS

The authors assessed the vital status on December 31, 1997 of a series of 382 patients with GC who were interviewed in 1985-1987 in the framework of a population-based case-control study in a high risk area for GC in Italy. Follow-up information at 10 years was available for all but three patients. The risk of dying was evaluated by Cox proportional hazard models, including patient age, gender, social status, disease stage at diagnosis, and lymph node involvement as confounding variables.

RESULTS

The overall survival probability was 0.26 at 5 years and 0.18 at 10 years after interview. The most important predictors were disease stage, lymph node involvement, and histopathologic grading (TNM classification). Overall, a high intake of alcohol was associated with an increased risk of dying (P = 0.02). In contrast, survival was increased in patients with a high intake of alpha-tocopherol (P = 0.04). A positive first-degree family history of GC was reported by 84 patients and tended to be associated with a reduced risk of death. A significant protective trend was found with increasing intake of vegetable fat and starch among these familial cases, with a 50% risk reduction. In contrast, this subgroup showed a two-fold increased risk of dying with a high intake of animal protein, animal fat, and preformed N-nitrosodimethylamine.

CONCLUSIONS

The current results provide evidence that premorbid diet may influence the prognosis of patients with GC, and they suggest that specific pathways for disease progression may exist among familial cases.

[Histopathologic examination of the intervertebral lumbar disk. Evaluation of its usefulness and limitations]

A retrospective clinical-pathological review of 192 lumbar intervertebral discs removed via an interlaminar approach or percutaneous nucleotomy from patients suffering from sciatic pain was carried out in order to assess if routine examination is useful. Only for a case of our series, which showed ill defined features at preoperative neuroradiologic imaging, an intraoperative pathologic examination was necessary. Immunohistochemical study was never required. A routine examination with a hematoxilin-eosin stain was sufficient also to recognize postoperative scar in patients reoperated. In conclusion we think that routine examination of the intervertebral disc is a procedure which is not expensive and useful to assess the nature of the lesion in reoperated patients and in rare cases showing unclear radiologic pattern.

Dietary and familial determinants of 10-year survival among patients with gastric carcinoma

BACKGROUND

Although the role of diet in gastric carcinoma (GC) causation has been investigated extensively, its association with long term survival has never been explored in detail.

METHODS

The authors assessed the vital status on December 31, 1997 of a series of 382 patients with GC who were interviewed in 1985-1987 in the framework of a population-based case-control study in a high risk area for GC in Italy. Follow-up information at 10 years was available for all but three patients. The risk of dying was evaluated by Cox proportional hazard models, including patient age, gender, social status, disease stage at diagnosis, and lymph node involvement as confounding variables.

RESULTS

The overall survival probability was 0.26 at 5 years and 0.18 at 10 years after interview. The most important predictors were disease stage, lymph node involvement, and histopathologic grading (TNM classification). Overall, a high intake of alcohol was associated with an increased risk of dying (P = 0.02). In contrast, survival was increased in patients with a high intake of alpha-tocopherol (P = 0.04). A positive first-degree family history of GC was reported by 84 patients and tended to be associated with a reduced risk of death. A significant protective trend was found with increasing intake of vegetable fat and starch among these familial cases, with a 50% risk reduction. In contrast, this subgroup showed a two-fold increased risk of dying with a high intake of animal protein, animal fat, and preformed N-nitrosodimethylamine.

CONCLUSIONS

The current results provide evidence that premorbid diet may influence the prognosis of patients with GC, and they suggest that specific pathways for disease progression may exist among familial cases.

Hodgkin's disease risk is increased in patients with ulcerative colitis

BACKGROUND & AIMS

All patients diagnosed with ulcerative colitis (UC) or Crohn's disease (CD) residing in Florence, Italy, in 1978-1992 were identified and included in a population-based study of cancer risk evaluation.

METHODS

A total of 920 patients were followed up (median, 11 years), and 64 newly diagnosed malignancies were identified by linkage to the local cancer registry. Expected cases were calculated on the basis of age- and sex-specific cancer incidence rates to estimate relative risks in comparison with the general population.

RESULTS

Overall, cancer incidence rates were not increased. A significant excess risk of Hodgkin's disease was observed among patients with UC (standardized incidence ratio, 9.3; 95% confidence interval [CI], 2.5-23.8). Respiratory tract cancers were significantly reduced to one fourth of the expected rate in patients with UC, but tended to be increased among patients with CD, who had a 50% higher risk of cancer at all sites. Only a nonsignificant, modestly increased risk of colorectal cancer was observed.

CONCLUSIONS

A strongly increased risk of Hodgkin's disease was evident in this first cancer follow-up of a representative series of patients with UC in a Mediterranean country. Two divergent risk patterns of respiratory tract cancers, possibly explained by differences in smoking habits, emerged in the 2 inflammatory bowel diseases.

Helicobacter pylori cag pathogenicity island is associated with enhanced interleukin-8 expression in human gastric mucosa

BACKGROUND

In vitro studies showed that Helicobacter pylori strains carrying the cag pathogenicity island are able to induce epithelial secretion of Interleukin-8.

AIMS

To evaluate the assessment of cag pathogenicity island and the expression of Interleukin-8 in the gastric mucosa of Helicobacter pylori-infected patients and correlate these data with the activity of gastritis and Helicobacter pylori density.

METHODS

cag status was determined by polymerase chain reaction directly on gastric biopsies from 13 Helicobacter pylori+ patients with non-ulcer dyspepsia and 13 Helicobacter pylori+ with duodenal ulcer. Interleukin-8 gene transcription and protein expression were analysed by in situ hybridization and immunofluorescence, respectively. Gastritis activity and Helicobacter pylori density were also investigated.

RESULTS

cag was present in 20/26 of Helicobacter pylori+ patients: in 7/13 non-ulcer dyspepsia (53.8%] and in 13/13 duodenal ulcer patients (100%), (p<0.05). Interleukin-8 mRNA and protein expression in epithelial and inflammatory cells was higher in cag+ than in cag- patients (p<0.005). Gastritis activity significantly correlated with cag (p<0.05) and Interleukin-8 expression (p<0.005]. Helicobacter pylori density was enhanced in cag+ [p<0.005] and correlated with Interleukin-8 expression (p<0.0051.

CONCLUSIONS

The present study demonstrates that in Helicobacter pylori-infected human gastric mucosa, cag+ infection is associated with enhanced Interleukin-8 expression, higher levels of active gastritis and bacterial density, and presence of duodenal ulcer.

Genetic and immunohistochemical analyses of p53 independently predict regional metastasis of gastric cancers

Either p53 gene mutation or immunohistochemical detection of p53 protein has not been consistently shown to have prognostic significance in human cancers, including gastric carcinomas. One hypothesis to explain this inconsistency is that some p53 mutations and p53 protein accumulation are not indicative of tumor progression. To test this hypothesis, we categorized p53 status in 105 gastric carcinomas according to types of mutations, numerical scores of immunohistochemical staining (IHC), or combinations thereof. The p53 status was then correlated with metastasis to liver or peritoneum. Gastric cancers with no p53 mutations were significantly less likely to metastasize than tumors with mutations. Intermediate IHC scores were inversely associated with metastasis. A substantial number of gastric cancers (31 of 105) showed positive p53 immunostaining without detectable mutations (p53-/IHC+), which suggested an accumulation of wild-type p53 protein, and also a significantly lower risk for metastasis. After adjusting for depth of invasion and lymph node involvement, the p53-/IHC+ combination predicted low metastatic risk better than either p53- or IHC+ with intermediate scores. These findings suggest that an accumulation of wild-type p53 protein occurs in gastric cancer cells and represents a stress-response mechanism that lowers metastatic potential.

Calf pseudohypertrophy in a patient with double neurogenic pathology

A pseudohypertrophy of the calf can be rarely associated with neurogenic pathologies as S-1 radiculopathy, poliomyelitis, spinal muscular atrophy, traumatic lesions of peripheral nerves, intraspinal neurinoma. The causes of this particular phenomenon are unknown. The authors present the case of a 52-year-old man with an enlargement of the left calf suffering from a mild form of spinal paralytic poliomyelitis in the early childhood and episodes of severe left sciatica in the last four years. Electromyography demonstrated a pattern of denervation in both legs and an H-reflex absent when the left tibial nerve was stimulated. An open muscle biopsy of the left calf was performed. Light microscopic and ultrastructural examination of the muscle confirmed the presence of a pattern of "neurogenic type" pseudohypertrophy. Our results could be interesting for the understanding of the mechanism of neurogenic pseudohypertrophy. This case suggests that timing of stimulus or "dose" of denervation may be important factors in such a phenomenon.

Intraoperative parathormone measurement in patients with multiple endocrine neoplasia type I syndrome and hyperparathyroidism

Total or subtotal parathyroidectomy is considered the treatment of choice for multiple endocrine neoplasia type I (MEN-I)-associated primary hyperparathyroidism (HPT). However, persistent or recurrent HPT is frequently observed. The development of a rapid two-site immunoradiometric assay (IRMA) method for measuring intact parathormone (PTH) has provided a valuable tool for recognizing possible surgical failures. Our experience includes 16 MEN-I patients (10 females, 6 males) of mean age 35.5 years operated on between 1990 and 1996. Total parathyroidectomy (TPTX) with autotransplantation of parathyroid tissue was the standard treatment. Blood samples for PTH measurement were drawn at the induction of anesthesia (basal value), 10 and 20 minutes after the removal of each gland, and 60 minutes after TPTX. Rapid PTH measurement, which required only 15 minutes of incubation at 37 degrees C, showed a highly significant correlation (p < 0.0001) with the standard method. Circulating PTH levels exhibited a stepwise decrease during TPTX, reaching a mean value of 22.3% of the baseline 20 minutes after removal of the last gland. Two patients showed a prompt decrease of PTH after removal of the single enlarged gland, featuring the kinetics observed in the adenomas. One of these two patients was successfully treated with more conservative surgery. None of the patients showed persistence or recurrence of HPT. In our experience, intraoperative measurement of PTH seems to be a valuable adjunct in both the diagnosis of multiglandular involvement and the prediction of surgical treatment in patients with primary parathyroid hyperplasia.

Parathyroid glands: combination of (99m)Tc MIBI scintigraphy and US for demonstration of parathyroid glands and nodules

PURPOSE

To determine the appropriate choice of imaging techniques for localization of nodular lesions of parathyroid glands.

MATERIALS AND METHODS

First, computed tomographic (CT), magnetic resonance (MR), ultrasonographic (US), and technetium 99m methoxyisobutyl-isonitrile (MIBI) scintigraphic images in 49 patients with primary hyperparathyroidism were retrospectively evaluated. A single-blind, prospective study that included 16 patients with primary hyperparathyroidism was then conducted. MR, US, scintigraphic, and color Doppler US images of the neck were obtained and analyzed.

RESULTS

In the retrospective study, CT, MR imaging, and US had low sensitivity (13%, 17%, and 27%, respectively) and specificity (39%, 65%, and 65%, respectively). Scintigraphy had 57% sensitivity and 85% specificity. In the prospective study, the use of latest-generation MR and US equipment and the participation of experienced operators led to improved sensitivity and specificity for these techniques. The combination of US and scintigraphy resulted in improved sensitivity (96%), specificity (83%), and positive and negative predictive values (88% and 94%, respectively), relative to the results obtained with either method alone. Doppler US was of little help in the setting of small glands.

CONCLUSIONS

The combination of (99m)Tc MIBI scintigraphy and US performed by well-trained operators with up-to-date instruments appeared to be the best diagnostic tool for the preoperative diagnosis of parathyroid disease.

Differing patterns of transforming growth factor-beta expression in normal intestinal mucosa and in active celiac disease

BACKGROUND

Growth-inhibitory autocrine polypeptides such as transforming growth factor (TGF)-beta may play a role in the control of normal epithelial cell proliferation and differentiation. In addition, TGF-beta has a central role in extracellular matrix homeostasis and regulates the immune response at the local level. In this study immunohistochemistry was used to examine the pattern of TGF-beta protein distribution and quantitative reverse transcription-polymerase chain reaction (RT-PCR) to determine levels of TGF-beta messenger RNA expression in normal intestinal mucosa and in the flat mucosa of children with celiac disease.

METHODS

Small intestinal biopsies were performed in children with active celiac disease and in histologically normal control subjects. Frozen sections were single stained using an anti-TGF-beta monoclonal antibody and were double stained for TGF-beta and T cell, macrophages, and the activation marker CD25. Total RNA was extracted from frozen specimens and competitive quantitative RT-PCR performed for TGF-beta mRNA using internal synthetic standard RNA.

RESULTS

In normal intestinal mucosa, by immunohistochemistry, TGF-beta expression was most prominent in the villous tip epithelium, whereas in the lamina propria, weak immunoreactivity was present. The celiac mucosa showed weak and patchy epithelial TGF-beta immunoreactivity. In contrast, an intense staining positivity was present in the lamina propria localized mostly in the subepithelial region where T cells, macrophages, and CD25+ cells were detected by double staining. By quantitative RT-PCR, levels of TGF-beta mRNA transcripts appeared to be increased in celiac intestinal mucosa compared with that in control subjects, although the difference did not reach statistical significance.

CONCLUSIONS

These observations suggest that TGF-beta expression is associated with differentiated enterocyte function. In celiac disease the lower TGF-beta epithelial cell expression could be a consequence of the preponderance of a less differentiated epithelial cell phenotype also present in the surface epithelium. In contrast, the prominent TGF-beta positivity of the subepithelial lamina propria suggests an association with the local immune and inflammatory response, as well as a potential role of these peptides in mesenchymal-epithelial cell interaction.

Inducible nitric oxide synthase expression in vascular and glomerular structures of human chronic allograft nephropathy

Nitric oxide (NO) plays an important role in the cytotoxic mechanisms responsible for acute renal allograft rejection, where macrophages produce high levels of inducible nitric oxide synthase (iNOS). By contrast, both the source and the role of NO in chronic allograft nephropathy (CAN) are still unclear. In this study, the expression of iNOS mRNA and protein was assessed in the kidneys of patients with graft failure due to chronic rejection. As controls, kidney specimens were obtained from patients undergoing nephrectomies for primary renal tumours, and from patients suffering from IgA nephropathy or mesangial-proliferative glomerulonephritis. In normal kidneys, iNOS production was absent or limited to a low signal, while it was found only in the inflammatory infiltrate of kidneys affected by glomerulonephritis, as assessed by immunohistochemistry and in situ hybridization. In contrast, in CAN, iNOS protein was localized not only in inflammatory cells, but also in vascular, glomerular, and, more rarely, tubular structures. Accordingly, in situ hybridization localized iNOS mRNA in both macrophages and lymphocytes, as well as in vascular structures and glomeruli. Double immunostaining for iNOS and a-smooth muscle actin (a-SMA) or von Willebrand factor (vWf) revealed that smooth muscle cells were the main vascular source of iNOS, while both mesangial and inflammatory cells were immunostained at the glomerular level. These data demonstrate that macrophages and lymphocytes are not the only source of iNOS mRNA and protein in human CAN. Vascular smooth muscle and mesangial cells also synthesize iNOS, raising the question of heterogeneous regulation and function of iNOS in this disease.

Estimation of prostate cancer volume by endorectal coil magnetic resonance imaging vs. pathologic volume

OBJECTIVE

Since tumor volume is recognized as an important predictor of clinical stage and disease outcome of prostate cancer, accurate preoperative estimation of tumor volume can play an important role in planning the appropriate treatment and establishing a patient's prognosis. We performed this study to evaluate the accuracy of the endorectal coil magnetic resonance (MR) technique for reliable prediction of tumor volume in patients with prostatic cancer.

MATERIAL AND METHODS

Endorectal coil MR imaging was performed in 57 consecutive men who were suspected to have prostate cancer. Subsequent ultrasound-guided transrectal biopsy revealed prostate cancer in 44 cases. The pathological volume of the surgical specimens of 25 selected patients who underwent radical prostatectomy was retrospectively compared to the volume estimated by endorectal coil MR studies, and the Pearson correlation coefficient was calculated.

RESULTS

In 15 patients the estimated size of the tumor was within 15% of the true tumor volume; in the remaining 10 cases MR imaging tended to underestimate large tumors and overestimate small ones. A significant correlation between the volumes as determined with MR imaging and measurements of surgical specimens was observed (r 0.94; slope 0.82). To our knowledge, this is the best correlation found between pathological volume and tumor volume as evaluated by any other imaging modality.

CONCLUSIONS

Endorectal coil MR imaging is a powerful means of evaluating the prostate gland; however, further improvements in imaging and/or volume calculation are required to provide a more accurate preoperative assessment of prostate cancer volume.

Implications of p53 mutation spectrum for cancer etiology in gastric cancers of various histologic types from a high-risk area of central Italy

Examination of p53 mutation spectra may provide clues to molecular mechanisms involved in different histologic types of gastric cancer. A total of 105 gastric cancer cases classified according to the Laurén's system were selected from a high-risk area around Florence, Italy. Exons 5-8 of the p53 gene were examined for mutations by the polymerase chain reaction-single strand conformation polymorphism technique and DNA sequencing, using DNA from formalin-fixed paraffin-embedded tissues. Mutation frequency was similar in intestinal-type (12/28) and unclassified tumors (9/18), but was significantly lower in diffuse cancers (12/57, P < 0.05). A similar frequency of p53 mutations was observed among tumor stages in both intestinal-type and unclassified cancers, but in diffuse tumors mutations tended to be associated with invasion beyond the muscularis propria. When base changes were considered, G:C-->A:T transitions at CpG sites were the most common mutations for all the three tumor types with 6 of 11 (55%) in intestinal type, 8 of 12 (67%) in diffuse type, and 5 of 8 (63 %) in unclassified tumors. Frequent p53 mutations in both intestinal-type and unclassified tumors support the hypothesis that unclassified tumors represent variants of the intestinal type and suggest that unclassified tumors, like the intestinal type, may also associate with environmental exposures. The predominance of G:C-->A:T transitions at CpG sites, which are associated with methyltransferase-induced DNA methylation at carbon 5 of cytosine, in all three tumor types suggests that the status of DNA methylation may be the major determinant for p53 mutations and may be also equally important in gastric carcinogenesis regardless of histology.