ABSTRACT
BACKGROUND: Enrolling patients in studies of pancreatic ductal adenocarcinoma (pdac) is challenging because of the high fatality of the disease. We hypothesized that a prospective clinic-based study with rapid ascertainment would result in high participation rates. Using that strategy, we established the Quebec Pancreas Cancer Study (qpcs) to investigate the genetics and causes of pdac and other periampullary tumours (pats) that are also rare and underrepresented in research studies. METHODS: Patients diagnosed with pdac or pat were introduced to the study at their initial clinical encounter, with a strategy to enrol participants within 2 weeks of diagnosis. Patient self-referrals and referrals of unaffected individuals with an increased risk of pdac were also accepted. Family histories, epidemiologic and clinical data, and biospecimens were collected. Additional relatives were enrolled in families at increased genetic risk. RESULTS: The first 346 completed referrals led to 306 probands being enrolled, including 190 probands affected with pdac, who represent the population focus of the qpcs. Participation rates were 88.4% for all referrals and 89.2% for pdac referrals. Family history, epidemiologic and clinical data, and biospecimens were ascertained from 91.9%, 54.6%, and 97.5% respectively of patients with pdac. Although demographics and trends in risk factors in our patients were consistent with published statistics for patients with pdac, the qpcs is enriched for families with French-Canadian ancestry (37.4%), a population with recurrent germ-line mutations in hereditary diseases. CONCLUSIONS: Using rapid ascertainment, a pdac and pat research registry with high participation rates can be established. The qpcs is a valuable research resource and its enrichment with patients of French-Canadian ancestry provides a unique opportunity for studies of heredity in these diseases.
ABSTRACT
The aim of this study was to investigate the role of cathepsin D in colorectal cancer. For this purpose cathepsin D expression was evaluated by means of immunohistochemistry in stromal and tumor cells of 31 colorectal carcinomas and 29 adenomas. Cytoplasmic cathepsin D expression of tumor cells was present in 90.3% of the carcinoma cases and various degrees of stromal cell cathepsin D expression were present in all cases. In the adenomas, the epithelial cells and stromal cells expressed cathepsin D in 68.96% and 96.55% of cases, respectively. The staining intensity was always weaker in the adenomas. When the stromal and tumor cell cathepsin D expression in the adenocarcinoma and adenoma cases were compared, a statistically significant difference was observed in the staining of stromal cells. Furthermore, stromal cathepsin D expression in the adenocarcinomas was related to tumor stage when the carcinomas were divided into low and high stage. Cathepsin D expression in stromal cells may be an important indicator of poor prognosis in colorectal adenocarcinomas.