The effect of alcohol on the risk of lung cancer in Uruguay

A hospital-based case-control study of the association between alcohol drinking and lung cancer was carried out in Uruguay between January 1988 and December 1990. The sample included 327 men with lung cancer and 350 male controls. Personal interviews were conducted in the Institute of Oncology by trained personnel using a structured questionnaire. The results showed a significant positive association between beer intake and the risk of lung cancer. The odds ratio for beer drinkers in the highest quartile was 3.4 (95% confidence limits, 1.3-6.6) after adjustment for tobacco. The association between beer and lung cancer was consistent for all the cell types, analyzed separately. A moderate effect for total alcohol consumption was also observed, with a relative risk of 2.2 for those subjects in the highest quartile.

Human gastric carcinogenesis: a multistep and multifactorial process--First American Cancer Society Award Lecture on Cancer Epidemiology and Prevention

Evidence from pathology and epidemiology studies has been provided for a human model of gastric carcinogenesis with the following sequential stages: chronic gastritis; atrophy; intestinal metaplasia; and dysplasia. The initial stages of gastritis and atrophy have been linked to excessive salt intake and infection with Helicobacter pylori. The intermediate stages have been associated with the ingestion of ascorbic acid and nitrate, determinants of intragastric nitrosation. The final stages have been linked with the supply of beta-carotene and with excessive salt intake. Nitrosating agents are candidate carcinogens and could originate in the gastric cavity or in the inflammatory infiltrate.

Treatment plans for black and white women with stage II node-positive breast cancer. The National Cancer Institute Black/White Cancer Survival Study experience

BACKGROUND

The National Cancer Institute Black/White Cancer Survival Study began patient accrual in 1985 and was designed to investigate factors that might contribute to the observed racial differences in survival for cancer of the breast, uterine corpus, colon, and bladder.

METHODS

To determine whether there were racial differences in treatment in a clinically homogeneous set of patients, 305 (25%) of the 1222 women in this study with Stage II node-positive (N+) breast cancer were evaluated.

RESULTS

Patient characteristics for blacks and whites were similar for age, metropolitan area of residence, tumor size, extent of nodal involvement, and steroid receptors. Differences in histologic findings, tumor grade, and nuclear atypia were observed. Blacks had a higher frequency of comorbid conditions, especially hypertension (P < 0.00001). Fewer blacks underwent breast-conserving surgery (P = 0.004). In a multivariate analysis, race was no longer a significant factor in the selection of primary treatment, but education and metropolitan area of residence remained significant. Blacks and whites received similar postoperative systemic therapy, with combination chemotherapy (cyclophosphamide, methotrexate, and 5-fluorouracil) and tamoxifen, the most common cytotoxic and endocrine therapies used.

CONCLUSIONS

The National Cancer Institute consensus statement concerning adjuvant therapy for breast cancer was published in the middle of the 2-year period that study cases were accrued, and treatment plans in this study generally agreed with consensus guidelines. Should survival differences in black and white patients with Stage II N+ disease in this study be found, they are unlikely to be attributable to differences in initial or postoperative treatment.

High prevalence and persistence of cytotoxin-positive Helicobacter pylori strains in a population with high prevalence of atrophic gastritis

Helicobacter pylori is strongly associated with both chronic gastritis and duodenal ulcer. Certain strains of H. pylori produce a vacuolating cytotoxin in vitro. At New Orleans Charity Hospital, concentrated culture supernatants from 119 of 144 (83%) H. pylori strains isolated from 86 patients at high risk of developing gastric cancer, caused vacuolization in HeLa S3 cells. Cytotoxin activity was neutralized by acid (pH 4) and basic (pH 10) solutions and proteases, and was precipitable by (NH4)2SO4, which suggests that the cytotoxin is a protein. In 66 of 86 (76.7%) patients, the H. pylori strains isolated from single or multiple sequential gastric biopsies had a vacuolating cytotoxin. These cytotoxin-positive H. pylori strains were isolated from 69% of patients with diffuse antral gastritis and 89% of patients with chronic atrophic gastritis. The latter lesion is considered a precursor of gastric cancer. The cytotoxicity persisted in sequential biopsies over an interval of several months, indicating persistence of these strains in the gastric mucosa. Fifty-eight percent (7/12) of the sera from cytotoxin-positive H. pylori-infected patients neutralized cytotoxin activity, whereas 20% (1/5) of sera from patients with H. pylori cytotoxin-negative strains and none of five H. pylori-negative patients' sera neutralized cytotoxin activity. The relevance of this cytotoxin in the pathogenesis of H. pylori-induced gastritis requires further study.

Immunohistochemical evidence of p53 overexpression in gastric epithelial dysplasia

Molecular abnormalities of the p53 gene in chromosome 17p may be among the most commonly observed in human cancer. Their role in gastric carcinogenesis is suggested by their frequent detection in invasive adenocarcinomas. To investigate the chronology with which these abnormalities appear in the gastric carcinogenesis process, the expression of p53 proteins was investigated in late stages of the process, namely dysplasia, and in superficial carcinomas. A polyclonal antibody, CM-1, against both wild-type and mutant proteins was applied to paraffin-embedded biopsy and gastrectomy specimens previously fixed in buffered formalin. Positive nuclear stain was obtained in 36.4% of 33 cases of gastric epithelial dysplasia, corresponding to 19% of mild, 27.3% of moderate, and 64.3% of severe dysplasias. Eight of 13 (61.5%) invasive carcinomas showed positive stain. The data indicate an increased incidence of p53 abnormalities in the late stages of gastric carcinogenesis.

Antibodies to Helicobacter pylori and pepsinogen levels in children from Costa Rica: comparison of two areas with different risks for stomach cancer

In children and adolescents from two areas of Costa Rica with contrasting gastric cancer risks, two factors suspected to be linked to the natural history of the disease were tested: serum antibodies to Helicobacter pylori and serum pepsinogen levels. One hundred fifty-five subjects from the high-risk area of Turrubares were compared to 127 from the low-risk area of Hojancha. No significant differences were found in the prevalence of IgG or IgA antibodies to Helicobacter pylori between the two regions. The prevalence of IgG was 65.8% in the high-risk area and 72.4 in the low-risk area, and that of IgA was 43% in both areas. The levels of pepsinogen, especially pepsinogen C, were significantly elevated in subjects with H. pylori antibodies in their serum. The mean levels of pepsinogen C in those negative, positive, and strong positive for H. pylori antibodies were 8.7, 14.3, and 21.1 ng/ml. These findings suggest that H. pylori-associated gastritis, predominantly of antral localization, is very prevalent in Costa Rican children and adolescents. Such gastritis might be associated with a high prevalence of intestinal metaplasia and a high gastric cancer risk in the inland, but not the coastal rural populations. H. pylori may therefore be an insufficient cause whose role in gastric carcinogenesis is contingent upon the presence of other factors.

Micronuclei in esophageal cells of Chinese youths in a high-incidence area for esophageal cancer in China

An epidemiologic survey among 538 young persons between 15 and 26 years of age in a high-risk area for esophageal cancer in the People's Republic of China revealed a high prevalence of esophagitis. Histologically confirmed very mild, mild, and moderate esophagitis was observed in 31.6%, 10.7%, and 1.1% of 354 male and 30.4%, 4.3%, and 1.1% of 184 female subjects. The prevalence of micronuclei in esophageal smears was assayed in a subsample to investigate its possible association with esophagitis and with risk factors for esophageal lesions. Of the 186 subjects, 2.7% had mild or moderate esophagitis, 19.9% had very mild esophagitis, and 77.4% were normal. The frequency distribution of micronucleated cells in the esophageal mucosa was similar for the three diagnostic groups. Mean percentages of micronucleated cells did not differ by diagnosis of esophagitis, household status, current smoking status, presence of oral leukoplakia, or consumption of burning hot beverages or fresh fruit. Higher mean percentages were observed in the older age group of both sexes, but the difference was not statistically significant. The results suggest that if esophagitis is considered an important precursor state in the development of esophageal cancer, the scoring of micronuclei does not appear to be an efficient test for mild forms of esophagitis.

Epidemiology of bronchioloalveolar carcinoma

Descriptive features of bronchioloalveolar carcinoma (BAC) are presented using Surveillance, Epidemiology and End Results Program population-based incidence data from 1973 through 1987, along with risk factors from histologically confirmed cases of BAC identified in a hospital-based case-control study conducted in Louisiana between 1979 and 1982. Compared to the rising incidence of lung cancer overall, BAC rates have remained relatively constant, accounting for less than 3% of all lung cancer. BAC incidence rates were higher in males, yet it explained proportionately more of the total lung cancer incidence in females. In the case-control study, 21 of the 33 cases originally ascertained from hospital pathology records were histologically confirmed as BAC. Most cases smoked cigarettes, with a 4-fold risk for ever smoking. Risks tended to increase with smoking intensity (reaching 10-fold for more than 1.5 packs/day) and duration (reaching 5-fold for more than 45 years of smoking). Following 10 or more years of employment, there was a 4-fold risk associated with motor freight occupations, along with nonsignificant excesses among construction workers, petroleum manufacturers, and sugar cane farmers. Cases were more likely than controls to have had emphysema or to have had a close family member with lung cancer. Although based on small numbers, this study suggests that BAC shares many of the epidemiological characteristics of lung adenocarcinoma.

A collaborative study of differences in the survival rates of black patients and white patients with cancer

In 1983, the National Cancer Institute began a social-epidemiologic study of possible behavioral and biologic determinants of black/white racial disparities in cancer survival. The design, methodology, underlying hypotheses, and patient accrual of this study are discussed. Survival differences in four organ sites are investigated: cancers of the uterine corpus, breast, bladder, and colon. The first three sites were chosen because of significant observed black/white differentials in survival. Although racial disparities in survival from colon cancer are less prominent, this site was included because it is a leading cause of deaths attributable to cancer, because regional variations have been observed in black/white survival disparities, and because colon data permit cross-gender comparisons. Data collection centers for the study included the Georgia Center for Cancer Statistics, the Louisiana Tumor Registry, and the California Tumor Registry. Probability samples of patients newly diagnosed with these cancers were drawn from the areas served by these registries. Diagnostic years of eligibility were 1985 to 1986 for breast and colon cancer, and 1985 to 1987 for bladder and uterine corpus cancer. Data were collected by personal interview, medical records abstract, physician records, and pathology review. Analyses focus on seven main explanatory hypotheses.

Cancer in south Louisiana. Part II: Gastrointestinal tract cancers

Incidence rates for the most common cancers of the gastrointestinal tract are presented for the 5 geographic regions in South Louisiana for the period 1983-1986. The risk of colorectal cancer, the most frequent GI cancer in males and females, is uniformly lower in these regions of South Louisiana than in other areas of the United States. Gastric cancer rates are significantly high in black males, as are pancreatic cancer rates in whites of both sexes compared to national rates.

Cancer in south Louisiana. Part III: Cancers of the breast and the reproductive system

Cancers of the breast and reproductive system are less common in South Louisiana than other parts of the nation. The only exception is invasive cervical cancer. Incidence rates for breast cancer in South Louisiana women are 20% lower than the SEER combined rates, and rates for cancer of the uterine corpus and the ovary among white women are 43% and 32% lower respectively than the SEER averages. South Louisiana men also have risks 14% (whites) and 30% (blacks) less than the national of developing prostatic cancer. These significantly low rates are observed for all regions in South Louisiana. The reasons for the low rates are not clearly understood. Possible explanations include: less frequent use of cancer screening tests, high prevalence of hysterectomy, lower risk exposures, and host/genetic factors. The low incidence rates for these cancers are not accompanied by more favorable mortality outcomes, suggesting a poorer survival among Louisiana cancer patients partially due to late stage disease at the time of diagnosis and treatment. Programs to increase the accessibility of cancer screening tests and improve early detection are greatly needed.

Cancer in south Louisiana. Part 1: Tobacco-related cancers

Tobacco-related cancers comprise about one third of the newly-diagnosed cancer in South Louisiana. These cancers are three times more common in men than in women. For cancers originating from anatomic sites where there is a direct contact with tobacco, ie, lung, larynx, oral cavity and pharynx, and esophagus, incidence rates for blacks are either higher than or similar to the rates for whites. For cancers of the bladder and the kidney, sites which have no direct contact with tobacco products, incidence rates are higher in whites than blacks. In general, white men in South Louisiana tend to have risks significantly higher than national for tobacco-related cancers, in particular, cancers of the lung (31% higher) and the larynx (42% higher). A similar pattern is observed for white females but is less pronounced. Black men in South Louisiana, on the other hand, have significantly lower rates than the SEER averages for cancers of the esophagus, oral cavity, and pharynx. Risks for other tobacco-related cancers are very comparable. There are very small differences in rates for black women between South Louisiana and SEER areas. Tobacco-related cancers are most preventable. Any effective cancer program in Louisiana must emphasize prevention and cessation of tobacco use.

Prospective study of Lewis antigen alterations in the gastric precancerous process

A prospective study with two gastric biopsies taken several years apart was carried out in 117 subjects with intestinal metaplasia who are of the Lewis(a-b+) phenotype. They are residents of a rural Andean region in Colombia displaying very high rates of gastric cancer. The anomalous expression of Lewis(a) antigens in the metaplastic epithelium carried a significantly increased risk of colonic metaplasia and dysplasia. Such risk was much higher when the simultaneous expression of sulfomucins and Lewis(a) antigen was observed.

Lewis antigen alterations in gastric cancer precursors

To explore the dynamics of the progressive loss of cell differentiation observed in the gastric precancerous process, the abnormal expression of Lea antigen in the gastric epithelium was investigated. Gastric biopsy specimens of 122 subjects with Le(a-b+) phenotype who had intestinal metaplasia of the gastric mucosa were studied. The subjects are residents of a rural area in the Colombian Andes with very high risk of gastric cancer. The abnormality was detected with increasing frequency in lesions with other markers of progression of the precancerous process, namely, colonic-type of morphology of the metaplastic cells, expression of sulfomucins, and dysplastic changes. The concomitant expression of the abnormal Lea antigen and sulfomucins was found to be a more reliable marker of more advanced lesions such as colonic metaplasia and dysplasia than either marker alone.

Diamond-Blackfan anemia: heterogenous response of hematopoietic progenitor cells in vitro to the protein product of the steel locus

Diamond-Blackfan anemia is a congenital disorder of erythropoiesis in humans, characterized by a macrocytic anemia often associated with physical anomalies. Mutations at either the W or Steel loci in the mouse also leads to a severe macrocytic anemia, as well as other developmental abnormalities. The W locus encodes the proto-oncogene c-kit, a member of the receptor tyrosine kinase family, while the Steel locus encodes a potent hematopoietic growth factor that is the ligand for c-kit. Growth of clonogenic marrow erythroid progenitor cells in vitro in the presence of the recombinant hematopoietic growth factors interleukin-3 (IL-3) and Steel was used to characterize this disease at the cellular level. Three patterns of in vitro marrow response to both recombinant IL-3 or Steel were observed among 10 Diamond-Blackfan patients: those that responded quantitatively and qualitatively almost as well as cells from normal marrow, those that responded at an intermediate level, and those that did not respond at all. These results provide evidence for cellular heterogeneity underlying the pathogenesis of this disorder and therefore raise the possibility that there may be more than one underlying molecular basis for the disease. No gross abnormalities in the structure of either the c-kit or Steel loci were observed in these patients. The normal response in culture of the progenitor cells from at least some patients to Steel with or without IL-3 raises the possibility of using this novel growth factor as a therapeutic agent in Diamond-Blackfan anemia.