The use of epidemiology, scientific data, and regulatory authority to determine risk factors in cancers of some organs of the digestive system. 6. Pancreatic cancer

Vitamin B6 Intake and Pancreatic Carcinoma Risk: A Meta-Analysis

Objectives: There are conflicting results for the association between vitamin B6 intake with reduced pancreatic carcinoma risk. Thus, a meta-analysis was performed to summarize the evidences from epidemiological studies. Methods: We searched documents from PubMed-Medline, Web of Science, and Cochrane Library. The results were analyzed by using Stata software. Results: A total of nine studies were included. The multivariate-adjusted results found that the total RR values of pancreatic carcinoma was 0.65 (95% CI: 0.53-0.80) for the highest vitamin B6 intake vs the lowest vitamin B6 intake, and there was no significant heterogeneity among studies (I2 = 42.0%, P = 0.087). Sensitivity analysis indicated that no single study leaded to an excessive change for the relation between vitamin B6 intake and pancreatic carcinoma risk. Conclusions: This meta-analysis suggested that vitamin B6 intake could significantly decrease pancreatic carcinoma risk. However, further study is needed based on the limitations of the current analysis.

Recent advances in pancreatic cancer: biology, treatment, and prevention

Pancreatic cancer (PC) is the fourth leading cause of cancer-related death in United States. Efforts have been made towards the development of the viable solution for its treatment with constrained accomplishment because of its complex biology. It is well established that pancreatic cancer stem cells (CSCs), albeit present in a little count, contribute incredibly to PC initiation, progression, and metastasis. Customary chemo and radiotherapeutic alternatives, however, expands general survival, the related side effects are the significant concern. Amid the most recent decade, our insight about molecular and cellular pathways involved in PC and role of CSCs in its progression has increased enormously. Presently the focus is to target CSCs. The herbal products have gained much consideration recently as they, usually, sensitize CSCs to chemotherapy and target molecular signaling involved in various tumors including PC. Some planned studies have indicated promising results proposing that examinations in this course have a lot to offer for the treatment of PC. Although preclinical studies uncovered the importance of herbal products in attenuating pancreatic carcinoma, limited studies have been conducted to evaluate their role in clinics. The present review provides a new insight to recent advances in pancreatic cancer biology, treatment and current status of herbal products in its anticipation.

Mortality and cancer experience of Quebec aluminum reduction plant workers, part 4: cancer incidence

OBJECTIVE

To describe the cancer experience of Quebec aluminum smelter workers.

METHODS

Cancer incidence was compared with that of the Quebec general population and examined in relation to benzo[a]pyrene (B[a]P) and smoking exposure indices.

RESULTS

There was a statistically significant increased incidence of stomach (two cohorts), pancreatic (one cohort), laryngeal (one cohort), lung (three cohorts), and bladder (four cohorts) cancers. Unlike lung and bladder cancers, pancreatic and stomach cancer risks do not relate meaningfully to cumulative B[a]P exposure. Laryngeal and buccal cavity cancer standardized incidence ratios (SIRs) seem to increase with increasing B[a]P exposure. SIRs from lung cancer have greatly diminished whereas bladder cancer SIRs remain elevated in all but one cohort.

CONCLUSIONS

The cancer incidence results are consistent with those from mortality studies, but identify other cancers that deserve scrutiny in future follow-ups.

Mortality and cancer experience of Quebec aluminum reduction plant workers. Part 2: mortality of three cohorts hired on or before january 1, 1951

OBJECTIVE

To describe the mortality of Quebec aluminum smelter workers employed before 1951.

METHODS

The mortality of 5,977 men hired at three plants on or before January 1, 1951 was compared with that of Quebec men. Relationships to benzo[a]pyrene, benzene-soluble material, and smoking were examined.

RESULTS

Statistically significant causes of death were lung cancer (three plants); bladder cancer; chronic obstructive lung disease (two plants each); cancers of the stomach, digestive system unspecified, rectum and rectosigmoid, pancreas, and larynx; Alzheimer's disease (one plant); and cerebrovascular disease (one plant). Not significant increases were also observed.

CONCLUSIONS

Mortality from cancer of the lung and bladder and chronic obstructive pulmonary disease are related to exposure in Söderberg smelters. The cause of increased stomach cancer mortality is unclear. Excess mortality from some other diseases may be explained by factors other than coal tar pitch volatiles exposure.

Cancer incidence among laboratory workers in biomedical research and routine laboratories in Israel: Part I-the cohort study

BACKGROUND

Laboratory work is associated with exposure to a mixture of carcinogens.

METHODS

The cohort is comprised of 4,300 laboratory workers. Cancer incidence was followed from 1960 to 1997.

RESULTS

A total of 230 cases were included in the cohort. The overall cancer standardized incidence ratio (SIR) was 1.04 (0.91-1.18). When a 20-year latency was introduced, SIR was increased significantly: 1.35 (1.13-1.61). Among routine workers and researchers, SIR was elevated significantly for the total population and for women, when a 20-year latency was introduced. SIR was also elevated significantly in research, routine, bacteriology and virology, and isotope laboratories. With respect to specific sites, significantly increased SIR was observed in breast, ovary, and thyroid cancer among women; and prostate cancer, leukemia, and melanoma among men.

CONCLUSIONS

We suggest that work in research and biomedical laboratories might involve an increased risk of certain types of cancer. Am. J. Ind. Med. 44:600-610, 2003.

Combined modality treatment with accelerated radiotherapy and chemotherapy in patients with locally advanced inoperable carcinoma of the pancreas: results of a feasibility study

Between July 1990 and September 1993, 32 patients with locally advanced irresectable adenocarcinoma of the pancreas, histologically proven by laparotomy, were involved in our study. Patients were treated with hyperfractionated, accelerated radiotherapy and simultaneous application of 5-fluorouracil and folinic acid. Chemotherapy was given on days 1,2 and 3. Determination of the target volume for radiotherapy was carried out by computerized axial tomography. The total tumour dose of 44.8 Gy was applied relative to the 90% isodose in two daily fractions of 1.6 Gy, resulting in ten fractions per week. On the first three days of radiotherapy, 600 mg m-3 of 5-fluorouracil and 300 mg m-3 of folinic acid were given i.v. According to response, chemotherapy was repeated in 4-week intervals. The median survival time for all patients was 12.7 months, compared with 3-7 months after palliative surgery (historical control). The median progression-free interval was 6.6 months. Toxicity and therapy-induced morbidity were recorded according to WHO criteria. Nausea and vomiting of WHO grade I and II occurred in 72.1% and of grade III and IV in 27.9% of the patients. WHO grade I and II diarrhoea was seen in 11 patients. The overall incidence of leucopenia and thrombocytopenia was 37.4%; severe side-effects (WHO III-IV) occurred in 9.3% of all patients. One patient experienced a severe mucositis (WHO III). This combined modality treatment consisting of accelerated hyperfractionated radiotherapy and chemotherapy turned out to be feasible for patients with locally advanced, irresectable pancreatic cancer. The therapy could be applied in a short period of time, approximately half the time used in conventional therapy schemes.

Longitudinal Gompertzian analysis of pancreatic cancer mortality in the U.S., 1962-1987: distinguishing between competitive and environmental influences upon evolving mortality patterns

Pancreatic cancer (PanC) is an extraordinarily lethal neoplasm that is currently the fifth leading cause of cancer death in the United States. Annual age-specific mortality rates for PanC in the U.S. from 1962 to 1987 were subjected to longitudinal Gompertzian analysis. Age-specific PanC mortality rate distributions between age 30 and 60 years were determined by a common fixed intersect point and a variable competitive factor. The intersect point for PanC occurred at age 59.5 years and mortality rate 37.4 per 100,000 for men, and at age 53.2 years and mortality rate 7.9 per 100,000 for women. These intersect points are determined by genetic and environmental influences upon mortality. The observation that these points have remained fixed suggests that there has been no significant alteration in environmental etiopathogenic influences upon PanC mortality. Longitudinal Gompertzian analysis suggests that the emergence of PanC in the U.S. as a significant cause of cancer mortality has been the consequence of competitive influences upon PanC mortality dynamics.

Serum diagnostic tests for pancreatic cancer

Serological tests for pancreatic cancer have been criticized too harshly as a result of being tested in inappropriate roles. They are never likely to become sufficiently specific for screening an asymptomatic population unless some way can be found of defining a population with a particularly high risk for the disease. Nor are they appropriate in the investigation of the jaundiced patient. The markers that are carried by secreted mucins seem the most promising and in view of the marked heterogeneity of carbohydrate expression on mucins a combination of tests for two or three carefully selected markers is likely to be better than one. The high cost per test that results from using commercially available radioimmunoassay kits with a short shelf-life can be reduced by using enzyme-linked assays which have a much longer shelf-life. These tests are likely to be of most help in the investigation of non-jaundiced patients with unexplained abdominal pain or weight loss. In this group of patients it seems probable that serological tests will compliment scanning techniques but further studies are needed to assess this.