Gastric cancer in a high-risk area in Italy. Histopathologic patterns according to Lauren's classification

Novel nomogram to predict the overall survival of postoperative patients with gastric signet

BACKGROUND

The TNM staging system cannot accurately predict the prognosis of postoperative gastric signet ring cell carcinoma (GSRC) given its unique biological behavior, epidemiological features, and various prognostic factors. Therefore, a reliable postoperative prognostic evaluation system for GSRC is required. This study aimed to establish a nomogram to predict the overall survival (OS) rate of postoperative patients with GSRC and validate it in the real world.

METHODS

Clinical data of postoperative patients with GSRC from 2002 to 2014 were collected from the Surveillance, Epidemiology, and End Results database and randomly assigned to training and internal validation sets at a 7:3 ratio. The external validation set used data from 124 postoperative patients with GSRC who were admitted to the Affiliated Tumor Hospital of Harbin Medical University between 2002 and 2014. The independent risk factors affecting OS were screened using univariate and multivariate analyses to construct a nomogram. The performance of the model was evaluated using the C-index, receiver operating characteristic curve (ROC), calibration curve, decision analysis (DCA) curve, and adjuvant chemotherapy decision analysis.

RESULTS

Univariate/multivariate analysis indicated that age, stage, T, M, regional nodes optimized (RNE), and lymph node metastasis rate (LNMR) were independent risk factors affecting prognosis. The C-indices of the training, internal validation, and external validation sets are 0.741, 0.741, and 0.786, respectively. The ROC curves for the first, third, and fifth years in three sets had higher areas under the curves, (training set, 0.782, 0.864, 0.883; internal validation set, 0.781, 0.863, 0.877; external validation set, 0.819, 0.863, 0.835). The calibration curve showed high consistency between the nomogram-predicted 1-, 3-, and 5-year OS and the actual OS in the three queues. The DCA curve indicated that applying the nomogram enhanced the net clinical benefits. The nomogram effectively distinguished patients in each subgroup into high- and low-risk groups. Adjuvant chemotherapy can significantly improve OS in high-risk group (P = 0.034), while the presence or absence of adjuvant chemotherapy in low-risk group has no significant impact on OS (P = 0.192).

CONCLUSIONS

The nomogram can effectively predict the OS of patients with GSRC and may help doctors make personalized prognostic judgments and clinical treatment decisions.

Medical image recognition and segmentation of pathological slices of gastric cancer based on Deeplab v3+ neural network

OBJECTIVE

In order to improve the efficiency of gastric cancer pathological slice image recognition and segmentation of cancerous regions, this paper proposes an automatic gastric cancer segmentation model based on Deeplab v3+ neural network.

METHODS

Based on 1240 gastric cancer pathological slice images, this paper proposes a multi-scale input Deeplab v3+ network, _and compares it with SegNet, ICNet in sensitivity, specificity, accuracy, and Dice coefficient.

RESULTS

The sensitivity of Deeplab v3+ is 91.45%, the specificity is 92.31%, the accuracy is 95.76%, and the Dice coefficient reaches 91.66%, which is more than 12% higher than the SegNet and Faster-RCNN models, and the parameter scale of the model is also greatly reduced.

CONCLUSION

Our automatic gastric cancer segmentation model based on Deeplab v3+ neural network has achieved better results in improving segmentation accuracy and saving computing resources. Deeplab v3+ is worthy of further promotion in the medical image analysis and diagnosis of gastric cancer.

Changing Patterns in Gastric Carcinoma

In order to document any modifications in age and sex distributions, tumor locations and histological types, a retrospective study was performed comparing 377 consecutive cases of gastric cancers observed from 1942 to 1956 with 359 cases diagnosed from 1986 to 1987. The mean age at diagnosis rose from 57 to 66 years with no significant male/female ratio variations (1.6 vs 1.7). Tumors located in the proximal stomach increased from 13 to 23 % (p < 0.001) whereas those arising in the distal stomach decreased from 66 to 50 % (p < 0.001). Intestinal type gastric carcinoma decreased from 65.5 to 52.6 % (p < 0.001). The diffuse type rose from 24 to 43 % (p < 0.001) and the mucoid type fell from 10.3 to 4.4 % (p < 0.001). In spite of the overall decline in intestinal type carcinomas, this form remained more common in the upper third area and increased from 55 to 70% (p<0.001). Significant modifications in the distribution of diffuse, mucoid and signet ring cell type carcinomas were also noted. The possible significance and implications of these observations are discussed.

Methodological Issues in a Multicentric Study of Gastric Cancer and Diet in Italy: Study Design, Data Sources and Quality Controls

The authors examine the problems of planning and conducting a multicentric case-control study on diet and gastric cancer in Italy. The solutions chosen for the study design, cases and controls identification, dietary interview, production of a common protocol for the field work are discussed. Results on the evaluation of the quality and comparability of collected data are presented. Further, compliance of cases and controls to the interview and to the blood and urine sampling with reasons of non-response are shown. Finally, the phases of the study and the methods for improving and controlling omogeneity among Centers are summarized.

Gastric cancer: epidemiology, prevention, classification, and treatment

Gastric cancer is the second most common cause of cancer-related deaths in the world, the epidemiology of which has changed within last decades. A trend of steady decline in gastric cancer incidence rates is the effect of the increased standards of hygiene, conscious nutrition, and Helicobacter pylori eradication, which together constitute primary prevention. Avoidance of gastric cancer remains a priority. However, patients with higher risk should be screened for early detection and chemoprevention. Surgical resection enhanced by standardized lymphadenectomy remains the gold standard in gastric cancer therapy. This review briefly summarizes the most important aspects of gastric cancers, which include epidemiology, risk factors, classification, diagnosis, prevention, and treatment. The paper is mostly addressed to physicians who are interested in updating the state of art concerning gastric carcinoma from easily accessible and credible source.

MDM2 oncogene, E3 ubiquitin protein ligase T309G polymorphism and risk of oesophageal or gastric cancer: meta-analysis of 15 studies

OBJECTIVE

To investigate the association between potentially functional MDM2 oncogene, E3 ubiquitin protein ligase (MDM2) T309G polymorphism and susceptibility to oesophageal or gastric cancer.

METHODS

Two investigators independently searched the PubMed and Chinese National Knowledge Infrastructure databases for studies published before September 2013.

RESULTS

Pooled results showed that the variant homozygous 309 GG genotype (versus TT) was significantly associated with increased risk of both oesophageal (odds ratio [OR] 0.77; 95% confidence interval [CI] 0.65, 0.90) and gastric cancer (OR 0.52; 95% CI 0.38, 0.72). Subgroup analysis revealed a 309 GG-associated increased risk for both cancer types in Asian populations, particularly among Chinese and Japanese ethnicity. When stratified for Helicobacter pylori infection and histological type of gastric cancer, the 309 GG-related risk was higher in H. pylori-positive patients (T versus G: OR 0.37; 95% CI 0.22, 0.63) and the association was stronger with intestinal (TT + TG versus GG: OR 0.68; 95% CI 0.54, 0.87) rather than diffuse gastric-cancer type.

CONCLUSIONS

The MDM2 T309G polymorphism may be significantly associated with increased susceptibility to oesophageal or gastric cancer, particularly among Eastern Asian populations.

Fruit and vegetable consumption and gastric cancer by location and histological type: case-control and meta-analysis

The available information favours a greater impact of environmental exposures on intestinal type gastric cancer, and risk factors for the cardia and distal stomach cancers also appear to be different. We aimed to estimate the association between fruit and vegetable intake and gastric cancer, by location and histological type. We performed a population-based case-control study and a meta-analysis of studies addressing this issue. Incident cases (n=305) were identified in two large teaching hospitals (Porto, Portugal), and controls were randomly sampled among city dwellers (n=1129). Published studies were searched through PubMed, and effects were combined with random effects meta-analysis. In our case-control study, the odds ratio (OR) for the comparison of the highest vs. lowest tertile of fruit consumption was 0.47 [95% confidence interval (CI): 0.21-1.05] for cardia, 0.53 (95% CI: 0.35-0.80) for non-cardia cancer, 0.36 (95% CI: 0.20-0.62) for intestinal, and 1.00 (95% CI: 0.53-1.90) for the diffuse histological type. For vegetables, the corresponding OR was 0.59 (95% CI: 0.26-1.35), 0.85 (95% CI: 0.58-1.26), 0.95 (95% CI: 0.57-1.57), and 0.60 (95% CI: 0.32-1.14). In meta-analysis, considering fruit consumption (highest vs. lowest category), the combined OR was 0.58 (95% CI: 0.38-0.89) for cardia, 0.61 (95% CI: 0.44-0.84) for non-cardia, 0.49 (95% CI: 0.33-0.72) for intestinal type, and 0.82 (95% CI: 0.57-1.20) for diffuse type. Vegetables also decreased the risk of cardia (OR=0.63, 95% CI: 0.50-0.79), non-cardia (OR=0.75, 95% CI: 0.59-0.95), intestinal (OR=0.61, 95% CI: 0.44-0.86), and diffuse type (OR=0.67, 95% CI: 0.44-1.01). Fruit or vegetable intake was associated with a decreased risk of gastric cancer regardless of the anatomical location and the histological type, although dietary intake had a more clear-cut protective effect on intestinal type cancers.

Time trend analysis of gastric cancer incidence in Japan by histological types, 1975-1989

Since different histological types (HT) of gastric cancer (GC) may differ in their aetiology, time trend analysis by HT may afford an insight into aetiology. From the Gastric Cancer Registry of Japan, 161 067 cases diagnosed were retrieved between 1975 and 1989 to calculate the annual relative frequencies, stratified by age group and sex, of HT according to the Lauren and the Japanese Research Society for Gastric Cancer (JRSGC) classifications. Age- and sex-specific incidence rates by HT were estimated by multiplying the corresponding national cancer incidence rates of GC by the relative frequencies. Logistic regression models stratified by sex and age group were fitted to determine the time trends of HT. Using the Lauren classification, a decreasing trend of the intestinal type and a stable trend of the diffuse type were found. By the JRSGC classification, significant decreasing trends for most age groups were found for papillary and mucinous adenocarcinomas. Tubular adenocarcinomas (well differentiated type) showed a decreasing trend only in younger age groups. Tubular (moderately differentiated type), poorly differentiated adenocarcinomas, and signet ring cell carcinoma were statistically stable during the period. Considering changes in lifestyles of the Japanese, the result suggests that there are three aetiological types of GC.

Time trend analysis of gastric cancer incidence in Japan by histological types, 1975-1989

Since different histological types (HT) of gastric cancer (GC) may differ in their aetiology, time trend analysis by HT may afford an insight into aetiology. From the Gastric Cancer Registry of Japan, 161 067 cases diagnosed were retrieved between 1975 and 1989 to calculate the annual relative frequencies, stratified by age group and sex, of HT according to the Lauren and the Japanese Research Society for Gastric Cancer (JRSGC) classifications. Age- and sex-specific incidence rates by HT were estimated by multiplying the corresponding national cancer incidence rates of GC by the relative frequencies. Logistic regression models stratified by sex and age group were fitted to determine the time trends of HT. Using the Lauren classification, a decreasing trend of the intestinal type and a stable trend of the diffuse type were found. By the JRSGC classification, significant decreasing trends for most age groups were found for papillary and mucinous adenocarcinomas. Tubular adenocarcinomas (well differentiated type) showed a decreasing trend only in younger age groups. Tubular (moderately differentiated type), poorly differentiated adenocarcinomas, and signet ring cell carcinoma were statistically stable during the period. Considering changes in lifestyles of the Japanese, the result suggests that there are three aetiological types of GC.

Decreasing incidence of both major histologic subtypes of gastric adenocarcinoma--a population-based study in Sweden

While the overall incidence of gastric cancer has fallen, presumably to a large extent in parallel with Helicobacter pylori infection, the occurrence of the diffuse histologic type is thought to have remained more stable, questioning the aetiologic role of H. pylori. We have analysed the incidence of the intestinal and diffuse types separately, while considering subsite (cardia/non-cardia). With an extensive prospective effort we identified all incident cases of gastric adenocarcinoma (n = 1337) in a well-defined Swedish population (1.3 million) 1989-1994. Tumours were uniformly classified histologically and topographically. Subgroup-specific incidence rates were computed and modelled using multivariate logistic regression. Site-specific trends were clearly discrepant. The overall incidence of adenocarcinoma distal to the gastric cardia declined by 9% (95% confidence interval 6-12%) per year, while cardia cancer remained stable. Thus, the feared rise in cardia cancer could not be confirmed despite clear site-specific trend discrepancies. The intestinal type predominated, especially in high-risk areas, while diffuse tumours prevailed among young patients and women. Both main histologic types of gastric adenocarcinoma declined markedly, at similar rapidity, and with no significant trend differences between the intestinal and diffuse types, even after multivariate adjustments. Our results are consistent with an aetiologic role of environmental factors including H. pylori also for diffuse-type gastric cancers.

Changing pattern of histological type, location, stage and outcome of surgical treatment of gastric carcinoma

BACKGROUND

There are indications that some features of gastric carcinoma are changing, with a possible impact on prognosis. The aim of this study was to examine any changes in type, location, stage, resection rate, postoperative mortality rate or prognosis for patients with gastric carcinoma in a well defined population.

METHODS

During 1974-1991, 1161 new cases of gastric adenocarcinoma were diagnosed in Ostergötland County, Sweden. Tumour location, Laurén histological type, tumour node metastasis (TNM) stage, radicality of tumour resection and postoperative complications were recorded after histological re-evaluation of tissue specimens and examination of all patient records. Dates of death were obtained from the Swedish Central Bureau of Statistics. Time trends were studied by comparing the intervals 1974-1982 (period 1) and 1983-1991 (period 2).

RESULTS

The proportion of diffuse type of adenocarcinoma increased (from 27 to 35 per cent), while that of mixed type decreased (from 16 to 9 per cent) and that of intestinal type was unchanged. The proportion of tumours located in the proximal two-thirds of the stomach increased (from 32 to 42 per cent) and the proportion of patients with tumours in TNM stage IV decreased (from 32 to 25 per cent). Overall tumour resection rates were unchanged, although the proportion of radical total gastrectomies increased (from 36 to 50 per cent). Excluding tumours of the cardia or gastric remnant after previous ulcer surgery, the 5-year relative survival rate after radical resection increased from 25 to 36 per cent and the postoperative mortality rate decreased for both radical (from 11 to 4 per cent) and palliative (from 18 to 6 per cent) resection.

CONCLUSION

The patterns of tumour histology, location and stage of gastric carcinoma have changed in the authors' region. These changes were paralleled by a significant improvement in survival and postoperative mortality rates.

P53 accumulation is a prognostic factor in intestinal-type gastric carcinoma but not in the diffuse type

BACKGROUND

The prognostic value of p53 nuclear accumulation in gastric cancer is still unclear, as shown by the discordant results still reported in the literature. In this study, we evaluated the correlation between p53 accumulation and long-term survival of patients resected for intestinal and diffuse-type gastric cancer.

METHODS

Eighty-three patients with carcinoma of the intestinal type and 53 patients with carcinoma of the diffuse type were included in the study. Immunohistochemical staining of the paraffin sections was performed by using monoclonal antibody DO1; cases were considered positive when nuclear immunostaining was observed in 10% or more of the tumor cells. Prognostic significance of different variables was investigated by univariate and multivariate analysis.

RESULTS

p53 positivity was found in 51.8% of intestinal-type and 50.9% of diffuse-type cases. No significant correlation between the rate of p53 overexpression and age, sex, tumor location, tumor size, depth of invasion, lymph node involvement, distant metastases, and surgical radicality was found in the two groups of patients. A statistically significant difference in survival rate was observed between p53-negative and p53-positive cases in the intestinal type (P < .05), confirmed by multivariate analysis (P < .005; relative risk = 3.09). On the contrary, no correlation with survival was found in diffuse-type cases according to p53 overexpression.

CONCLUSIONS

These results suggest that the immunohistochemical detection of p53 accumulation is a useful indicator of poor prognosis in the intestinal but not in the diffuse type of gastric cancer, and are indicative of distinct molecular pathways and pattern of progression in the two histotypes.

Histopatologia do câncer de estômago (classificação de Lauren) em amostra de pacientes hospitalares no Rio de Janeiro, 1980-1995

Foi selecionada uma amostra aleatória (334 indivíduos) de todos os pacientes diagnosticados com câncer de estômago no período de 1980 a 1995 no Instituto Nacional do Câncer, Rio de Janeiro, sendo revisados seus dados histopatológicos. A concordância entre os diagnósticos prévios e atuais quanto à Classificação de Lauren foi considerada substancial (kappa= 0,65). Baseando-se nesta classificação, observou-se um declínio estatisticamente não significativo das proporções de câncer gástrico de tipo intestinal em idosos (sessenta anos ou mais) de ambos os sexos (em homens, 41,0% no período de 1980-1985, 37,9% de 1986 a 1990 e 28,8% de 1991 a 1995; entre mulheres, as proporções foram, respectivamente de 41,4%, 31,5% e 15,2%). As proporções de câncer gástrico de tipo intestinal permaneceram relativamente estáveis para os pacientes menores de sessenta anos.

Clinicopathological significance of intestinal and diffuse types of gastric carcinoma in Taiwan Chinese

The present study sought to evaluate the clinicopathological features of our gastric cancer patients in terms of a modified Lauren's histological classification and compared the results with those from studies from Japan and Western countries. A total of 536 consecutive patients with gastric cancer were treated surgically between December 1987 and December 1993. A clinicopathological analysis was only performed for intestinal types (IT) and diffuse types (DT) of gastric cancer because patients falling into the 'other' category were too small to produce meaningful data. Of 536 cases of gastric cancer, 268 (50%) were IT, 231 (43.1%) were DT and 37 (6.9%) were of the other type. The overall IT:DT ratio was 1.2. Gastric cancer patients with IT (in contrast to DT) were characterized by older age, male dominance, smaller tumours, the tumour often being located in the lower and upper third of the stomach and less peritoneal metastasis. In both sexes, the peak incidence of gastric cancer patients was in the age group 65-74 years. Men had higher proportions of IT carcinoma than women. The IT:DT ratio for men and women was 1.4 and 0.4, respectively. Although the increased ratio of IT:DT paralleled the advance of age in both sexes, the transitional age (the age at which the IT:DT ratio exceeds 1.0) in male patients (age group 51-64 years) was earlier than for female patients (age group 65-74 years). Patients with IT gastric cancer had a significantly better survival rate than those with DT. However, the type of carcinoma (IT or DT) was not an independent predictor of survival. These data indicate that gastric cancer in Taiwan Chinese has different biological behaviour in terms of IT and DT. The clinicopathological features in IT and DT carcinoma are similar to studies from Japan and from Western countries.

Gastric carcinoma in the Sultanate of Oman: Incidence and distribution

Gastric carcinoma has always been considered a major problem in the Sultanate of Oman. This study was conducted to document the cases in Oman over a two-year period, in order to determine incidence, age, sex and geographical distribution of the condition. All cases of gastric carcinoma in Omani nationals presenting to the medical facilities throughout Oman from November 1987 to November 1989 were reviewed from pathology records, surgical database records and by personal communication with surgeons at regional hospitals. Specimens taken at surgery or endoscopic biopsy were examined and classified according to Lauren's criteria. Over the two-year period, 104 cases of gastric carcinoma were observed. This represented an annual incidence of 4.2/100,000 population, but when adjusted to the standard European population age distribution (in the Oman population, 51% are under 15 years of age), the incidence was 8.6/100,000. The male:female ratio was 1.6:1 and the peak age group was 60-69. All tumors were advanced and most were located in the antral part of the stomach. There were more intestinal types of tumors than diffuse and a preponderance of intestinal metaplasia. This first survey of stomach carcinoma in Oman will provide a reference for future studies and indicates the need for earlier detection.

Gastric carcinoma: correlation of diagnosis based on biopsies and resection specimens with reference to the Laurén classification

Gastric carcinomas in 382 patients were studied histologically and the results from the preoperative endoscopic biopsies were compared with those from the resected specimens. Using the Laurén classification an overall histological diagnostic agreement between the two specimens was reached in 317 cases, or 83%. The highest diagnostic agreement, 87%, was for intestinal carcinomas. For diffuse carcinomas the diagnostic agreement was 75%. The disagreement in intestinal carcinomas was mainly due to foci of undifferentiated cells and/or signet-ring cells predominating in the biopsy. The disagreement in diffuse carcinomas was mainly because glandular structures were present at the surface in some of the cases and therefore led to an erroneous diagnosis of intestinal carcinoma. In conclusion, the intestinal type of gastric carcinoma can in most cases be diagnosed correctly from an endoscopic biopsy, whereas the diagnosis of a diffuse carcinoma is less accurate until the resected specimen is available for histological study.

Epidemiology of intestinal and diffuse types of gastric carcinoma. A time-trend study in Finland with comparison between studies from high- and low-risk areas

The incidence of gastric cancer has declined markedly in Finland during the last 4 decades. To document the changes caused by that in the ratio of the intestinal type (IT) to the diffuse type (DT) of gastric carcinoma we compared the 367 cases diagnosed from southwestern Finland at the Department of Pathology, Turku University, from 1950-1959 and 1076 cases from 1980-1989. IT virtually disappeared in the male and female populations younger than 50 years, and in patients younger than 60 years, DT became more common than IT (P < 0.001). The transitional age, the time at which IT exceeds DT in frequency, shifted by 20 years to older age groups. In patients older than 60 years, IT remained the dominant type, but the ratio of IT to DT (IT:DT) decreased in men from 3.8 to 2.1 (P < 0.05) and in women from 4.4 to 2.1 (P < 0.001). No decrease in the frequency of DT could be demonstrated in the material studied. The disappearance of the male-dominant IT in the younger male population changed the male-to-female ratio of patients reported to the Finnish Cancer Registry. When the ratio IT:DT in Finland was compared with the ratios reported by the authors in data from other continents and by other investigators, regional variations in basal level of IT:DT emerged. This phenomenon seems to be based on the differing genetic susceptibility to DT of various races. The decrease of IT, seen in reports from regions with declining incidence of gastric carcinoma, seems to be connected to a diminished rate of severe chronic gastritis.

A case-control study of gastric cancer and diet in Italy. III. Risk patterns by histologic type

In a case-control study of gastric cancer (GC) in high-risk and low-risk areas of Italy, 923 GCs were systematically categorized by one pathologist according to the Lauren classification distinguishing 2 main histologic types, intestinal (55%) and diffuse (23%). Intestinal types outnumbered diffuse types by a 3 to 1 margin in high-risk regions in the north-central part of the country, while both types occurred at nearly equal rates in low-risk areas. Intestinal types also occurred relatively more frequently at older ages and among males. Relative risks of each type of GC were evaluated in relation to dietary and other data obtained from interviews with the cancer patients and controls. The risk patterns for intestinal and diffuse types were remarkably similar. Increased risks of both types were associated with high intake of meat, salted/dried fish, seasoned cheeses and traditional soups, while decreased risks of both types were found among heavy consumers of fresh vegetables and fruits. Correspondingly similar patterns were seen with indices of nutrients, with risks of both intestinal and diffuse GC rising with animal protein intake and declining with consumption of vitamins C and E. Both types were inversely related to socio-economic status, and neither was associated with cigarette smoking. A familial history of GC was reported more frequently by patients with each type than by controls, although the highest risk was for unclassified GC, a group of poorly differentiated and medullary carcinomas accounting for 15% of all GCs in this study. The findings suggest that, despite differences in geographic and demographic patterns, the intestinal and diffuse types of GC have etiologic factors in common.

Reproducibility of histologic classification of gastric cancer

A panel review of histologic specimens was carried out as part of a multi-centre case-control study of gastric cancer (GC) and diet. Comparisons of diagnoses of 100 GCs by six pathologists revealed agreement in histologic classification for about 70-80% of the cancers. Concordance was somewhat higher when using the Lauren rather than the Ming or World Health Organization classification systems. Histologic types from reading biopsy tissue agreed with those derived from surgical specimens for 65-75% of the 100 tumours. Intra-observer agreement in histologic classification, assessed by repeat readings up to 3 years apart by one pathologist, was 95%. The findings indicate that, although overall concordance was good, it is important to standardise diagnoses in multi-centre epidemiologic studies of GC by histologic type.

Familial occurrence of gastric cancer in the 2-year experience of a population-based registry

The authors studied the familial occurrence of tumors in 154 individuals with gastric cancer by reviewing the clinical data and the genealogical tree of all patients registered in 1986 through 1987 in the Local Health Care District of Modena, Italy, for cancer of the stomach. Crude and age-adjusted (world population) incidence rates of gastric cancer were 34.0 and 21.4 new cases/100,000/year, respectively, in men, and 24.5 and 10.9 in women, respectively. Among first-degree relatives of the registered patients there were 30 cases of gastric carcinoma versus 15 cases in a control group matched for age and sex (Mantel-Haenszel odds ratio [M-H OR] 3.14, P less than 0.01). This excess of gastric neoplasms was observed in siblings (17 versus 7, M-H OR 4.33, P less than 0.02) but not in parents (13 versus 8, not significant). Besides gastric cancer, there was no significant excess of other type of tumors in case families. The familial occurrence of gastric cancer tended to be more frequent in patients with "diffuse" carcinoma (52%) than in subjects with "intestinal" cancer (33%), although the difference was not statistically significant. In conclusion, the current investigation suggests that a "family history" for gastric neoplasms is usually observed in approximately 10% to 15% of the registered cases. As already described for other common malignancies, therefore, the familial occurrence of gastric carcinoma suggests the existence of a genetic susceptibility to cancer of the stomach, at least in a fraction of these patients.

A case-control study of gastric cancer and diet in Italy

A case-control study was conducted in high- and low-risk areas of Italy to evaluate reasons for the striking geographic variation in gastric cancer (GC) mortality within the country. Personal interviews with 1,016 histologically confirmed GC cases and 1,159 population controls of similar age and sex revealed that the patients were more often of lower social class and resident in rural areas and more frequently reported a familial history of gastric (but not other) cancer. After adjusting for these effects, case-control differences were found for several dietary variables, assessed by asking about the usual frequency of consumption of 146 food items and beverages. A significant trend of increasing GC risk was found with increasing consumption of traditional soups, meat, salted/dried fish and a combination of cold cuts and seasoned cheeses. The habit of adding salt and the preference for salty foods were associated with elevated GC risk, while more frequently storing foods in the refrigerator, the availability of a freezer and use of frozen foods lowered risk. Reduced GC risk were associated with increasing intake of raw vegetables, fresh fruit and citrus fruits. Lowered risk was also related to consumption of spices, olive oil and garlic. Neither cigarette smoking nor alcoholic beverage drinking were significantly related to GC risk. The case-control differences tended to be consistent across geographic areas, despite marked regional variations in intake levels of certain foods. The high-risk areas tended to show higher consumption of food associated with elevated risk (traditional soups, cold cuts) and lower consumption of foods associated with reduced risks (raw vegetables, citrus fruits, garlic). Our findings indicate that dietary factors contribute to the regional variation of stomach cancer occurrence in Italy, and offer clues for further etiologic and prevention research.