CYP2E1 RsaI and 96-bp insertion genetic polymorphisms associated with risk for colorectal cancer.

We investigated a possible association between alcoholism, cigarette smoking, obesity and CYP2E1 RsaI and 96-bp insertion genetic polymorphisms with risk for colorectal cancer (CRC). Patients with CRC (70 women and 61 men) were matched for gender and age to 206 healthy controls. The mean age of the two groups was 62 years. Meat intake, cigarette smoking and alcohol drinking were assessed using a specific frequency questionnaire. The body mass index was also calculated. DNA was extracted from peripheral blood; RsaI polymorphism genotypes were evaluated by PCR-RFLP and 96-bp insertion genetic polymorphisms were evaluated by specific primers. The distributions of CYP2E1 RsaI c1/c1, c1/c2 and c2/c2 genotypes were 90.2, 9.2 and 0.6%, respectively, in controls and 83.9, 13.7 and 2.4% in CRC cases. Allele c2 was associated with increased risk for CRC [odds ratio (OR) = 1.88, 95% confidence interval (95%CI) = 1.02-3.45]. The CYP2E1 RsaI c2/c2 genotype was associated with an increased risk for rectal cancer (OR = 3.23, 95%CI = 1.26-9.03). The 96-bp insertion was slightly more frequent in the CRC group (9.3 vs 11.4%, P = 0.19), especially in females (6.4 vs 11.5%, P = 0.34). Smoking, alcohol drinking or high intake of red meat and CYP2E1 polymorphisms were not associated with increased risk for CRC. The 96-bp insertion was marginally more frequent (P = 0.07) in undernourished CRC subjects. We concluded that the risk for CRC is higher among individuals with allele c2. The CYP2E1 RsaI c2/c2 genotype was associated with an increased risk for rectal cancer.

Over-expression of cyclooxygenase-2 in endoscopic biopsies of ectopic gastric mucosa

Ectopic gastric mucosa (EGM) is considered to be a congenital condition. Rare cases of adenocarcinoma have been described. There are no data justifying regular biopsies or follow-up. Cyclooxygenase-2 (COX-2) is a protein involved in gastrointestinal tumor development by inhibiting apoptosis and regulating angiogenesis. The aim of this prospective study was to evaluate COX-2 expression in EGM and compare it with normal tissue and Barrett's esophagus. We evaluated 1327 patients. Biopsies were taken from the inlet patch for histological evaluation and from the gastric antrum to assess Helicobacter pylori infection. Biopsies taken from normal esophageal, gastric antrum and body mucosa and Barrett's esophagus were retrieved from a tissue bank. EGM biopsies were evaluated with respect to type of epithelium, presence of H. pylori, and inflammation. COX-2 was detected by immunohistochemistry using the avidin-biotin complex. EGM islets were found in 14 patients (1.1 percent). Histological examination revealed fundic type epithelium in 58.3 percent of cases, H. pylori was present in 50 percent and chronic inflammation in 66.7 percent. Expression of COX-2 was negative in normal distal esophagus, normal gastric antrum and normal gastric body specimens (10 each). In contrast, EGM presented over-expression of COX-2 in 41.7 percent of cases and Barrett's esophagus in 90 percent of cases (P = 0.04 and 0.03, respectively). COX-2 immunoexpression in EGM was not related to gender, age, epithelium type, presence of inflammation or intestinal metaplasia, H. pylori infection, or any endoscopic finding. Our results demonstrate up-regulation of COX-2 in EGM, suggesting a possible malignant potential of this so-called harmless mucosa.

Immunoexpression of cyclooxygenase-1 and -2 in ulcerative colitis.

Ulcerative colitis (UC) is a disease of the colon and rectum characterized by a nonspecific chronic inflammation mediated by the concerted response of cellular and humoral events. Prostaglandins are synthesized by cyclooxygenase (COX)-1 and -2 and exhibit both pro- and anti-inflammatory activity. To evaluate COX-1 and COX-2 immunoexpression in 42 cases of UC and to correlate it with clinicopathological parameters, COX-1 and COX-2 expression was investigated by the immunohistochemistry method. Only patients with all pertinent clinical and evolutive data as well as with adequate biopsy material were included in the study. Fifteen samples of colorectal adenocarcinoma and 14 of large bowel with no histological changes were used for positive and negative controls, respectively. UC patients showed COX-1 immunoreactivity in epithelial cells in 29% of the cases and in inflammatory cells in 43%. COX-2 positivity in epithelial and inflammatory cells was found in 69% of the samples. The comparison between UC and the control groups revealed that the UC group had significantly more positive cases for COX-1 and COX-2 in inflammatory cells. Immunohistochemistry allowed the identification of COX-1 and COX-2 expression in epithelial and inflammatory cells in UC biopsies. No significant difference between COX-1 and COX-2 immunoreactivity in epithelial and inflammatory cells was observed regarding the clinicopathological parameters. COX-2 presented low expression in normal colon and high expression in colorectal adenocarcinoma. COX-2 might play a role in the pathophysiologic processes of inflammatory bowel disease and the development of neoplasia. Treatment with selective COX-2 inhibitors might be an additional option for therapy.

Immunoexpression of cyclooxygenase-1 and -2 in ulcerative colitis

Ulcerative colitis (UC) is a disease of the colon and rectum characterized by a nonspecific chronic inflammation mediated by the concerted response of cellular and humoral events. Prostaglandins are synthesized by cyclooxygenase (COX)-1 and -2 and exhibit both pro- and anti-inflammatory activity. To evaluate COX-1 and COX-2 immunoexpression in 42 cases of UC and to correlate it with clinicopathological parameters, COX-1 and COX-2 expression was investigated by the immunohistochemistry method. Only patients with all pertinent clinical and evolutive data as well as with adequate biopsy material were included in the study. Fifteen samples of colorectal adenocarcinoma and 14 of large bowel with no histological changes were used for positive and negative controls, respectively. UC patients showed COX-1 immunoreactivity in epithelial cells in 29 percent of the cases and in inflammatory cells in 43 percent. COX-2 positivity in epithelial and inflammatory cells was found in 69 percent of the samples. The comparison between UC and the control groups revealed that the UC group had significantly more positive cases for COX-1 and COX-2 in inflammatory cells. Immunohistochemistry allowed the identification of COX-1 and COX-2 expression in epithelial and inflammatory cells in UC biopsies. No significant difference between COX-1 and COX-2 immunoreactivity in epithelial and inflammatory cells was observed regarding the clinicopathological parameters. COX-2 presented low expression in normal colon and high expression in colorectal adenocarcinoma. COX-2 might play a role in the pathophysiologic processes of inflammatory bowel disease and the development of neoplasia. Treatment with selective COX-2 inhibitors might be an additional option for therapy.

Ki-67 as a prognostic marker in colorectal cancer but not in gastric cancer.

The growth of tumors is highly variable and this probably reflects even its clinical course. The monoclonal antibody Ki-67 recognises an antigen present in the nuclei of cells in all phases of the cell cycle except G0. In the current study, we examined by immunohistochemistry the proliferative activity, based on Ki-67 labeling index (Ki67LI), in formalin-fixed and paraffin-embedded sections of 152 tumors, being 70 gastric and 89 colorectal cancers. The results obtained were correlated with the clinicopathologic factors. The carcinomas showed a wide range of Ki-67LI, reflecting a variation in proliferative activity. The tumor labeling index ranged from 10 to 85 per cent positivity, being the mean level in gastric cancer tissue 0.52 and in colorectal cancer 0.44. There was also heterogeneity of labeling within many of the tumors. No significant correlation was found between Ki-67LI and sex, age, clinical stage in these cancers. In colorectal cancer, but not in gastric cancer, high levels of Ki67LI have been correlated with poor survival. Ki-67 staining is a simple and useful method for estimating proliferative activity. The importance of Ki-67 as an indicator of tumor behaviour is not clear. In colorectal cancer this index may be used as a marker of prognosis.

Laminin concentration in ascites of patients with hepatic cirrhosis and peritoneal carcinomatosis.

Laminin levels in ascitic fluid have been proposed as a marker for neoplastic ascites. We compared the concentration of laminin in serum and in ascitic fluid from patients with hepatic cirrhosis and peritoneal carcinomatosis and assessed the diagnostic value of serum laminin levels in differentiating neoplastic from benign ascites. Laminin concentrations were determined by ELISA with antibodies against laminin extracted from the human placenta, in patients with ascites due to peritoneal carcinomatosis (N = 20) and hepatic cirrhosis (N = 33). Patients with infected or hemorrhagic ascites were excluded. The receiver operating characteristic curve was used to determine the sensitivity and specificity of serum laminin for the diagnosis of neoplastic ascites. When compared to the group with cirrhosis, the carcinomatosis group presented significantly higher mean laminin levels in serum (3.3 +/- 0.5 vs 2.1 +/- 0.4 microg/ml, mean +/- SD, P < 0.05) and ascites (2.8 +/- 0.5 vs 1.6 +/- 0.4 microg/ml, P < 0.05). Although laminin concentration was higher in serum than in ascites, the laminin serum/ascites ratio and serum-ascites gradient did not differ between the studied groups. A significant correlation (r = 0.93, P < 0.0001) was observed between the serum and ascites laminin values. Serum laminin levels >2.25 microg/ml showed 100% sensitivity and 73% specificity for the diagnosis of neoplastic ascites. Serum concentration seems to be the main determinant of laminin levels in ascitic fluid and its values can be used as a diagnostic parameter in the study of neoplastic ascites.

Laminin concentration in ascites of patients with hepatic cirrhosis and peritoneal carcinomatosis

Laminin levels in ascitic fluid have been proposed as a marker for neoplastic ascites. We compared the concentration of laminin in serum and in ascitic fluid from patients with hepatic cirrhosis and peritoneal carcinomatosis and assessed the diagnostic value of serum laminin levels in differentiating neoplastic from benign ascites. Laminin concentrations were determined by ELISA with antibodies against laminin extracted from the human placenta, in patients with ascites due to peritoneal carcinomatosis (N = 20) and hepatic cirrhosis (N = 33). Patients with infected or hemorrhagic ascites were excluded. The receiver operating characteristic curve was used to determine the sensitivity and specificity of serum laminin for the diagnosis of neoplastic ascites. When compared to the group with cirrhosis, the carcinomatosis group presented significantly higher mean laminin levels in serum (3.3 ± 0.5 vs 2.1 ± 0.4 æg/ml, mean ± SD, P < 0.05) and ascites (2.8 ± 0.5 vs 1.6 ± 0.4 æg/ml, P < 0.05). Although laminin concentration was higher in serum than in ascites, the laminin serum/ascites ratio and serum-ascites gradient did not differ between the studied groups. A significant correlation (r = 0.93, P < 0.0001) was observed between the serum and ascites laminin values. Serum laminin levels >2.25 æg/ml showed 100 percent sensitivity and 73 percent specificity for the diagnosis of neoplastic ascites. Serum concentration seems to be the main determinant of laminin levels in ascitic fluid and its values can be used as a diagnostic parameter in the study of neoplastic ascites.

[Squamous cell carcinoma of the canal anal]. / Carcinoma espinocelular de canal anal: análise de 11 casos.

BACKGROUND: Anal cancer is an uncommon malignancy accounting for only a small (4%) percentage of intestinal cancer. The authors described the clinical aspects and the treatment of the patients with squamous cell carcinoma of the canal anal. PATIENTS: Eleven patients with squamous cell carcinoma treated among 1995 and 1999, were analyzed retrospectively. Nine were women and two were men. The mean age was 57.6 years old (range 35-82 years old). RESULTS: The most common symptoms were rectal bleeding, local tumor and pain. Six of them had previous anal benign disease and two had metastases at the diagnosis. All were submitted to systemic chemotherapy with 5-fluorouracil and mitomycin and radiotherapy with 4500 cGy. Four patients had residual disease after chemo radiation and salvage surgery with abdominoperineal resection was done. Three patients had recurrence and four died from the disease. CONCLUSION: Most of our patients were women. The chemo radiation can be a curable treatment in patients with local disease; conversely in patients with residual disease, abdominoperineal resection must be done. Although anal cancer is an often curable disease, four patients died because the diagnosis was done in advanced stage.

Serum levels of interleukin-2 and tumor necrosis factor-alpha correlate to tumor progression in gastric cancer.

BACKGROUND/AIMS: The aim of this study was to assess serum levels of Interleukin-2 and tumor necrosis factor-alpha with disease progression and correlate these levels with CEA and CA19-9 serum levels. METHODOLOGY: Serum levels of interleukin-2 and tumor necrosis factor-alpha were measured in 23 patients with gastric cancer (being 9 stage I or II and 14 stage III or IV) and 10 patients without cancer by ELISA using Predicta Genzyme Diagnostica. The patients were followed for at least 2 years or until death. CEA and CA19-9 were also measured in both groups by ELISA (Abbott Diagnostic). RESULTS: Patients with gastric cancer stage III or IV had elevated levels of these cytokines (P = 0.002 for IL-2 and P = 0.003 for tumor necrosis factor-alpha). There was no difference between the serum levels of tumor necrosis factor-alpha and interleukin-2 in patients with gastric cancer stage I or II and the control group (P > 0.05). We also found no difference among the groups for CEA and CA19-9 (P = 0.17 and 0.72, respectively). Only one gastric cancer patient stage I or II had elevated level of IL-2 and none had elevated levels of tumor necrosis factor-alpha. In the group of patients with gastric cancer stage III or IV, 87.5% of them with elevated levels of tumor necrosis factor-alpha and 75% of them with elevated levels of interleukin-2 died during the follow-up. CONCLUSIONS: We conclude that serum interleukin-2 and tumor necrosis factor-alpha are associated with advanced gastric cancer and that these cytokines might be a useful tumor marker for gastric cancer, being associated with poor prognosis.

Relationship between mesenteric and peripheral blood levels of CA 19-9 in patients with colorectal cancer.

INTRODUCTION: CA19-9 is one of the most important tumor markers used in patients with colorectal cancer, mainly in radical surgery follow-up. AIM: The purpose of this study was to evaluate the preoperative CA19-9 level obtained from a peripheral vein (PV) and compare it to the level obtained from the mesenteric vein (MV). MATERIALS AND METHODS: Blood was collected from a PV of the arm and from the MV of 59 patients with colorectal cancer before primary surgery. Of these 59 patients fourteen had stage I disease, 10 stage II, 22 stage III, and 13 stage IV. CA19-9 was determined in serum by immunoenzymatic assay (Abbott Diagnostica). RESULTS: Fifteen patients (24%) had elevated serum levels of CA19-9 in the MV and 13 (22%) in the PV. None of the stage I or II patients had elevated serum levels of CA19-9. There were no differences between marker levels in blood collected from the MV or PV, independent of clinical stage. The CA19-9 values obtained from the MV differed significantly in the different stages of the disease according to the Kruskal-Wallis analysis (p=0.026); this difference was not statistically significant (p=0.08) in serum from the PV. There was no correlation between venous infiltration by the tumor and positivity of CA19-9 serum levels collected from the mesenteric vein. We observed a close correlation between the serum levels of CA19-9 collected from the PV and from the MV (r=0.9). CONCLUSION: The current study demonstrates a close correlation between the serum levels of CA19-9 collected from a peripheral vein and from the mesenteric vein. Our results confirmed the poor sensitivity of serum CA19-9 at diagnosis, independent of the collection site.

[AgNOR in stomach neoplasm]. / AgNOR em câncer gástrico.

OBJECTIVE: To study the proliferative activity of AgNORs (argyropholic nucleolar organizer region) in gastric cancer tissue and in the adjacent normal tissue and correlate with the clinical and pathological parameters. MATERIAL AND METHODS: Thirty four formalin-fixed paraffin-embedded tissues sections of patients with adenocarcinoma of the stomach were analysed retrospectively, being 23 of intestinal and 11 of diffuse type of Lauren. The AgNORs can be detected by a specific silver staining and the number de AgNORs was counted in 100 nucleus of tumoral cells and in 100 nucleus of the adjacent normal tissue. RESULTS: The tumoral cells had numerous, smaller, aggregated or one solitary and bigger AgNORs in the nuclei, while the normal cells had one or two AgNORs by nuclei. A significant difference was found between the mean numbers of AgNORs in the nuclei of tumor (3.86) and the normal tissue (1.25). There was also a significant difference between intestinal (4.43) and diffuse type (2.58) means. No significant correlation was found between mean AgNOR count and sex or age of the patients. CONCLUSIONS: The quantification of AgNORs can be used as a marker of proliferative activity, helping on the diagnosis of cancer.

C-erbB-2 oncoprotein in gastric carcinoma: correlation with clinical stage and prognosis.

The aim of this study was to investigate the expression of the oncogene c-erbB-2 in gastric tumors. Immunohistochemical study of the expression of c-erbB-2 was performed in formalin-fixed, paraffin-embedded sections from 82 gastric adenocarcinomas using polyclonal antibody. c-erbB-2-positive immunostaining was observed in 37 (45%) tumors. Positive staining was detected in 63% of well differentiated, 46% of moderately differentiated and 80% of papillary adenocarcinomas. In poorly differentiated adenocarcinomas, positivity for c-erbB-2 was observed in 21 %. According to the Lauren classification, a higher frequency of c-erbB-2 positive staining was observed in intestinal type tumors (70%). During the follow-up period 43% of the patients with c-erbB-2 oncoprotein-negative tumors and 45% of the patients with c-erbB-2 oncoprotein-positive tumors died. There was no significant association between c-erbB-2 staining and sex, age, clinical stage, tumor grade, histological type or survival rates. In conclusion, almost half of the gastric cancers were positive for c-erbB-2. Nonetheless, the expression of c-erbB-2 oncoprotein did not play a role in prognosis.

[Frequency of polyps in patients undergoing surgery for colorectal cancer]. / Freqüência de pólipos em doentes operados de câncer colorretal.

INTRODUCTION: Epidemiologic and molecular biologic studies have already demonstrated that adenomatous colonic polyps are precancerous diseases. The main indication of the colonoscopy in the surveillance of colorectal cancer treated patients is the diagnosis and resection of adenomatous polyps. AIM: To study the frequency of adenomatous polyps after surgically resection of colorectal cancer. MATERIAL AND METHODS: Sixty eight patients, mean age 59 years old, with total resection of colorectal cancer, submitted to various colonoscopies during the follow up were studied retrospectively. The histological type and the characteristics of the polyp were described. RESULTS: The frequency of polyps was 18%, being higher in the patients with more than 45 years (20%). The site of the polyps was in the left colon in 38% of the patients with cancer. The histological type of adenomas was tubular in 61%, villous in 22% and mixed in 17%. DISCUSSION: As described by other authors, the incidence of polyps were higher after 45 years old and more than a half of them were tubular. The frequency of polyps was higher in the first two years of follow up.

[Multiple primary neoplasms in colorectal cancer patients] . / Neoplasias primárias múltiplas em pacientes com câncer colorretal.

INTRODUCTION: Multiple primary neoplasms are defined as a second malignance having histology and site different from the first. The increase of the life expectation in cancer patients leads to an increase in multiple primary neoplasms incidence. This study analyzes the characteristics of patients with colorectal cancer and another primary neoplasms. PATIENTS AND METHODS: In the period from 1993 to 1998, 145 patients with colorectal cancer were accompanied in the Oncology Division of Gastroenterology of Federal University of São Paulo, São Paulo, SP, Brazil. Five patients (3.4%) had multiple primary neoplasms. The possibility of metastasis were excluded and the second cancer was confirmed by hystological examination. RESULTS: The medium age was of 60.6 years old, four were female and one male. Three had rectum cancer and two colon cancer, one in the right colon and one in the left colon. The other site of cancer was breast, uterus, uterus and vagina, skin and lip. One patient died and the others were in attendance, two for more than three years. Two patients received pelvic radiotherapy before the rectal cancer. In one patient the tumor colorectal cancer appeared before the other cancer, and in four it appeared later on to the diagnosis of the other primary neoplasia. DISCUSSION: The prevalence of multiple primary neoplasms was of 3.4%, being major in female. Uterus' cancer was the more frequent association. Radiotherapy was performed in 40% of patients. We believe that attendance of cancer patients is very important to precocious diagnosis and treatment of multiple primary neoplasms.

[Hepatocellular carcinoma: treatment of 23 cases]. / Carcinoma hepatocelular: tratamento de 23 casos.

In this study, we compared the clinical aspects of the patients with hepatocarcinoma treated in the Clinical and Surgical Gastroenterology Division, Federal University of São Paulo Medical School. Thirty three patients with hepatocarcinoma were treated between 1989 and 1997, 23 were treated surgically or by chemotherapy. Ten of them, in bad clinical conditions, were treated only with supportive treatment. Among the 23 treated patients, 12 were treated surgically, 10 with transcatheter arterial chemoembolization and one with systemic chemotherapy. The liver nodes size varied from 2.6 to 20 cm, being 82% greater than 5 cm. The mean survival was 14.8 months for the surgical treated patients and 9.8 months for the transcatheter arterial chemoembolization treated patients. These differences were not significant by the Kaplan-Meyer curve. The patients with liver nodes under 5 cm had better survival (P < 0.05). We can conclude that independent of the clinical stage, the size of the liver node is an important factor on prognosis. Patients with live nodes smaller than 5 cm have better survival than the others with greater tumors.

p53 in epidermoid cancer of the esophagus.

BACKGROUND/AIMS: Wild type p53 protein has an inhibitory effect on cell proliferation and transformation. Mutation or deletion of the p53 gene can be the first point of malignancy. Abnormalities of the p53 protein gene have been linked with tumors of the esophagus. METHODOLOGY: In this study, we investigated the expression of the p53 gene in epidermoid carcinoma of the esophagus as well as in the basal layer near the tumor. We studied the expression of p53 in 24 esophageal tumors and in normal esophageal tissue near the tumor in 16 cases, using an immunohistochemical reaction. RESULTS: p53 was positive in 18 esophageal tumors (75%) and in 15 of the 16 (94%) normal samples of esophageal tissue. There was no correlation between expression of the p53 gene and age, sex, tobacco intake, alcoholism, and familiar history of cancer or clinical stage of the disease. The mean survival of the p53 patients (negative or positive) was similar. CONCLUSIONS: p53 accumulation was found in most cases of esophageal cancer as well as in samples of normal tissue close to the tumor. The positivity of p53 seems to be independent of clinical or pathological parameters and was not of any use in predicting prognosis in our study.

CEA and CA 19-9 as prognostic indexes in colorectal cancer.

Carcinoembryonic Antigen (CEA) and CA 19-9 are tumor markers expressed by colorectal cancers (CR), particularly in advanced cases. The aim of this study was to evaluate the prognostic value of pre-operative elevated CEA and/or CA 19-9 levels for patients with CR. Blood samples were collected from 74 patients. CEA and CA 19-9 were determined by ELISA (normal range: 0-3 ng/ml for CEA and 0-37 U/ml for CA 19-9). All patients were followed-up for at least 30 months or until death. At the time of diagnosis, 42% of the patients had elevated serum levels of CEA and 35% of CA 19-9. Relapse was observed in 33 patients, 73% of whom had elevated CEA and/or CA 19-9 levels. Among patients without relapse, 68% and 73% had normal values of CEA and CA 19-9, respectively. Ninety-three percent of patients, who had CR recurrence during the first year, had an elevated CEA and/or CA 19-9 level, while 67% of the patients with CR after 1 year, had normal tumor markers. Elevated pre-operative serum CEA and CA 19-9 levels were each predictive of increased cancer mortality (p = 0.001 for CEA, p = 0.01 for CA 19-9). Raised CEA and CA 19-9 levels identify patients at high risk for CR and death and may be useful in selecting patients for adjuvant therapy.

Estrogen and progesterone receptors in gastric and colorectal cancer.

BACKGROUND/AIMS: Estrogen (ER) and progesterone receptors (PR) have been evaluated in gastrointestinal cancer by several groups with conflicting results. The aim of the study is to examine the presence of these receptors in gastric and colon cancer. METHODOLOGY: Estrogen (ER) and progesterone (PR) receptors were assayed by the dextran-coated charcoal adsorption method from malignant and normal adjacent tissues in 16 patients with gastric adenocarcinomas and in 10 with colorectal adenocarcinomas. RESULTS: In gastric cancer, ER were detected in 62.5% and PR in 75% of the patients. In colorectal cancer, the ER and PR were detected in 60% of the patients. The binding activity ranged from 1.14-9.27 fmol/mg protein for estradiol and from 1.43-10.84 fmol/mg protein for progesterone. ER and PR were detected in normal gastric tissue in 62.5% and in 50%, respectively. In the normal colorectal tissue the ER and PR were detected in 30% and 50%. ER ranged from 1.20-16.63 fmol/mg protein for estradiol and from 1.44-9.94 fmol/mg protein for progesterone. There was no statistical difference in levels of ER and PR in both tissues. CONCLUSIONS: ER and PR were detected in normal and cancer tissues in low levels, suggesting a feature of the tissue rather than a consequence of a malignant process. Eventual role of ER or PR in these cancers remains to be elucidated.

[Determination of proliferative activity using Ki67 and expression of p53 in colorectal cancer]. / Determinação da atividade proliferativa pelo Ki67 e p53 em doentes com câncer colorretal.

BACKGROUNDS AND PURPOSE: Classically, neoplasia has been considered a disturbance in the regulation of proliferation. In the search of a prognostic discriminant, the distribution of Ki67 as a marker of cell proliferation and the expression of p53 was studied in patients with colorectal cancer, to see whether this marker correlate with clinicopathological aspects. PATIENTS AND METHODS: Formalin-fixed paraffin-embedded tissues from 38 surgically resected adenocarcinomas of colon and rectal (5 Dukes A, 15 B and 18 C) were examined for p53 and Ki67 reactivity by immunohistochemistry (Dako). Nuclear staining of 5% of the cells was the criterion for a positive p53 reaction. For the study of Ki67 10 or more fields were chosen until 1000 nuclei per specimen were counted. The Ki67 labelling indices was determined by the number of positive nuclei/1000 cells. Correlation was done with the Dukes stage, grade of differentiation and percentual of recurrence. RESULTS: The mean Ki67 labelling indices was 40. The p53 was positive in 79% of the patients. The mean of Ki67-Li was higher in the positive p53 patients. However we did not lymphatic find differences between Ki67 or p53 expression and sex, age, Dukes stage, grade of differentiation, neural, venous or lymphatic invasion or recurrence. CONCLUSION: Ki67 and p53 could not be correlated to clinical and pathologic parameters in this study and was of limited use as a prognostic discriminant. The positive p53 cancers have more proliferative activity detected by a higher index of Ki67.

Cholesterolemia in colorectal cancer.

BACKGROUND/AIMS: Colorectal cancer incidence is higher in developed countries. High fat intake is one of the risk factors. However, many studies observed lower cholesterol serum levels on diagnosis of colorectal cancer. The aim of this assay was to study the serum cholesterol levels in patients with colorectal cancer and compare these values with individuals of the same age and sex. METHODOLOGY: Cholesterol serum levels of 85 patients with colorectal cancer were determined. Each of the patients with colorectal cancer were matched with an individual without cancer of the same age and sex. Total cholesterol concentrations were determined using an enzymatic colorimetric method. RESULTS: The mean serum of cholesterol was 183.4 for the colorectal group and 209.7 for the control group. This difference was statistically significant. This difference was more evident in patients with colon cancer and older than 60 years of age. There was no difference between the different Dukes' stage. CONCLUSIONS: Our study suggest an association between low blood cholesterol and colorectal cancer. We believe that the lower level of cholesterol observed in these patients is a consequence between the difference of colorectal carcinogenesis.