Biomedical subjects

Juan C Araya

Publications and source records attributed to Juan C Araya.

6 recordsLinked to original sources

PubMed2006

Preneoplastic lesions in gallbladder cancer.

BACKGROUND: Gallbladder cancer is an uncommon disease except in countries like Chile and areas of India and Japan. The knowledge regarding the etiology and mechanisms through which this neoplasia is developed is significantly less compared to other malignant tumors. RESULTS: The epithelial lesions involved in gallbladder carcinogenesis are dysplasia and adenomas that represent two biologically distinct carcinogenetic models. Dysplasia progresses to carcinoma in situ (CIS) and subsequently becomes invasive. Over 80% of invasive gallbladder cancers present areas adjacent to the CIS and epithelial dysplasia. Other authors have demonstrated adenomatous areas in carcinomas, or malignant transformation in an adenoma. The low incidence of gallbladder adenomas (0.14% of cholecystectomies) and the presence of adenomatous remnants in the neighboring mucosa to early carcinomas in less than 3% of the cases suggest the limited importance of this carcinogenic pathway. Epithelial dysplasia which is not associated with gallbladder cancer is observed in approximately 1% of cholecystectomies for symptomatic lithiasis. Metaplasia, dysplasia, and CIS are present in the mucosa adjacent to the cancer in 66%, 81.3%, and 69%, respectively. The average ages of patients with dysplasia not associated to cancer (51.9 years), early carcinomas (56.8 years), and advanced carcinomas (62.9 years) demonstrate a gradient which suggests the progression of these lesions. CONCLUSIONS: From the morphological point of view, the dysplasia-carcinoma sequence is the most plausible carcinogenic pathway for gallbladder cancer, a process which would require a period of approximately 10 years.

Adenocarcinoma↗

PubMed2004

[Clinicopathological features of gallbladder polyps and adenomas].

BACKGROUND: Chile has a high frequency of gallbladder cancer. Polyps are common lesions of gallbladder mucosa but there is little information about their morphological features. AIM: To report the clinical and pathological features of 219 gallbladder polyps. MATERIAL AND METHODS: Cholecystectomites samples in which a polypoid lesion was diagnosed microscopically. In all cases, complete clinical information and digitalized images of the complete surgical specimens was reviewed. RESULTS: In a period of 10 years, 21,412 gall-bladders were processed. Among these, 884 carcinomas were diagnosed and in 219 cases (1%) a polyp was found. One hundred and eighty three patients were females (mean age 49.3 years) and 36 males (mean age 53.4 years). The preoperative diagnosis of gallbladder polyp wars done only in 26 cases (12%). Eighty five percent of polyps were non-neoplastic (metaplastic in 32%, cholesterol in 29%, hyperplastic in 22% and inflammatory in 2%). The remaining 15% were adenomas. Seventy five percent of non-neoplastic polyps were located in the proximal half of the gallbladder and 88% of adenomas in the distal half. Ninety five percent of non-neoplastic polyps measured less than 10 mm. Among adenomas, 47% measured less than 5 mm and 28% more than 10 mm. Smaller polyps were of cholesterol and larger polyps were adenomas. Eight adenomas were associated with an adenocarcinoma, two had less than 5 mm length. Mean age of patients with adenomas associated to cancer was higher than patients with pure adenomas (64.6 and 44.3 years respectively, p > 0.001). CONCLUSIONS: There are size and location differences between non neoplastic polyps and adenomas. Adenomas associated to cancer may measure less than 5 mm. Therefore the polyp size criteria to decide surgical behavior in symptomatic gallstone patients may be misleading.

Adenocarcinoma↗

PubMed2004

[DNA content and survival in subserous gallbladder carcinoma].

BACKGROUND: The clinical and morphological characterization of the subserous gallbladder carcinomas is controversial. AIM: To study the prognostic importance of DNA content of subserous gallbladder carcinoma. MATERIAL AND METHODS: We studied 104 females aged 60+/-12 years old and 16 men aged 70+/-13 years old. In all of them diagnosis was established after mapping of cholecystectomy sample and had a complete clinical follow up. DNA content was measured by flow cytometry. RESULTS: All tumors were adenocarcinoma, and only 16% were well differentiated. Aneuploidy was observed in 29 cases (26%) with DNA index fluctuating between 1.1 and 1.8. Lymphatic vessel tumor involvement was present in 16 of 22 cases with aneuploidy and in 22 of 46 diploid tumors (p=0.05). Eighty nine percent of aneuploid tumors were detected macroscopically and 11% were unapparent. Five years survival was non significantly better among patients with diploid tumors than in patients with aneuploid tumors (45 and 28%, respectively, p=0.2). The histological differentiation was the only variable significantly associated with survival. CONCLUSIONS: Aneuploidy is present in 26% of subserous gallbladder carcinoma. It is not related with any of the morphological or clinical variables studied in this series of patients.

Adenocarcinoma↗

PubMed2004

[Detection of bone marrow micrometastases in patients with gallbladder cancer].

BACKGROUND: There is a very strong documented correlation between the appearance of cancer cells in blood and occurrence of metastasis in gastrointestinal cancer. AIM: To determine MUC1, CK19, CK20 and CEA mRNA expression in bone marrow of patients with gallbladder cancer and evaluate its clinical significance. MATERIAL AND METHODS: Sixty eight samples were analyzed, 38 bone marrow samples of gallbladder cancer patients, 20 healthy donors, and 10 frozen samples of gallbladder cancer. Nested reverse transcriptase-polymerase chain reaction (nested RT-PCR) was used to analyze mRNA expression. RESULTS: All frozen tumors were positive for CEA, CK19, and MUC1 mRNA and 70% were positive for CK20. Seventeen of 20 donor samples were positive for MUC1 and only one sample from donors was positive for both CK20 and CK19 mRNA. Among the 38 blood and bone marrow samples of gallbladder cancer patients, the expression of MUC1, CK19, CK20, and CEA, mRNA was 60.5% (23/38), 31.6% (12/38), 7.9% (3/38), and 7.9% (3/38), respectively. Disregarding the MUC1 results. 37% (14/38), 13% (5/38) and 5% (2/38) were positive for one, two and three markers respectively. Not significant differences were found in survival with a follow up to 12 months. CONCLUSION: Our results indicate that the molecular detection of tumor cells in bone marrow in patients with gallbladder carcinoma is technically possible, being CEA, CK19 and CK20 gene expression the best markers. The MUC1 gene expression marker was highly unspecific and it should not been considered. The detection of bone marrow micrometastasis might be helpful in prognosis and the selection of clinical treatment but a larger series with a longer follow-up should be studied.

Adult↗

PubMed2002

[Morphological prognostic elements in gallbladder cancer].

BACKGROUND: The exact survival rates and prognostic factors of gallbladder cancer are still incompletely known. AIM: To report the actuarial survival of patients with gallbladder cancer. MATERIAL AND METHODS: Six hundred thirty seven women, aged 59 years old as a mean and 108 men, aged 64 years old as a mean, with gallbladder cancer are reported. Patients were followed for up to 150 months. RESULTS: Two hundred twenty four patients had an early and 521 had an advanced carcinoma. Overall survival was 38% at ten years. Sex or ethnic origin did not influence survival. Early tumors had a 92% survival at 10 years whereas the survival of advanced tumors was 16% at 5 years. Subserous tumors had a 5 years survival of 32% whereas serous tumors had a 5 years survival of 11%. Well-differentiated advanced tumors had a significantly better survival than moderately or poorly differentiated tumors. Vascular or lymphatic infiltration was also associated to a lower survival. All patients with advanced tumors and vascular infiltration died before 5 years. CONCLUSIONS: Tumor infiltration and differentiation degree were the most important prognostic independent factors in gallbladder cancer.

Adenocarcinoma↗

PubMed2002

[Is gallbladder cancer a disease with bad prognosis?].

Gallbladder cancer is frequent in Chile, but it is not uniformly mortal. The diagnosis is usually made after a cholecystectomy, indicated for a symptomatic cholelithiasis. Global survival of gallbladder cancer can be as high as 40% at five years. In 69% of women of less than 30 years old, the tumor is detected in early stages. In these cases, cholecystectomy is the curative procedure, with a 90% survival at five years. According to our experience, cholecystectomies should be performed between 40 and 50 years of age in men and between 30 and 40 years in women. The prognostic factors that should be considered are symptoms associated to lithiasis, age, parity, obesity, size of stones and the size of the gallbladder. If the tumor is detected in early stages, the survival is good. The natural history of the disease would change significantly if all women with symptomatic stones were operated.

Adult↗