Cáncer de vesícula biliar ¿la contaminación por bilis afecta el pronóstico? / Gallbladder Cancer: does bile contamination affect the prognosis?

Resumen Introducción: En algunas áreas el cáncer de la vesícula biliar se detecta en hasta el 3,5% de los pacientes intervenidos por colelitiasis. Con el objetivo de evaluar el rol de la ruptura de la vesícula y la consiguiente contaminación por bilis, se evaluó una serie de pacientes portadores de cáncer de vesícula diagnosticado posterior a la colecistectomía. Materiales y Método: El estudio se efectuó en 109 pacientes en quienes se diagnosticó un cáncer de vesícula posterior a la colecistectomía. El grupo a estudiar se dividió de acuerdo a la ocurrencia o no de contaminación por bilis al momento de la colecistectomía, como también de acuerdo a la magnitud de ésta. Resultados: De los pacientes estudiados, en 32 se documentó la ocurrencia de contaminación por bilis al momento de la colecistectomía. De estos, en 13 la contaminación fue considerada mayor. El tiempo promedio de seguimiento fue de 33 meses, 35 pacientes (32,1%) fallecieron durante el seguimiento. La sobrevida media de la totalidad de la serie que tuvo contaminación por bilis no se diferenció de los pacientes sin contaminación. Sin embargo, el grupo que tuvo una contaminación catalogada como mayor, presentó una sobrevida estadísticamente inferior al resto de los pacientes. Finalmente, se realizó un análisis mediante el modelo de regresión de COX que incluyó edad, género, nivel de invasión y tipo de contaminación, resultando la existencia de contaminación mayor por bilis un factor independientemente asociado al pronóstico. Conclusión: La presencia de ruptura vesicular y contaminación mayor por bilis debiera considerarse un factor pronóstico.

Background: Incidental gallbladder cancer is observed in up to 3.5% of patients undergoing laparoscopic cholecystectomy. To study the role of wall perforation on the prognosis, we evaluated a series of patients in whom perforation occurred during the cholecystectomy. Materials and Method: 109 patients who underwent a laparoscopic cholecystectomy in whom final diagnosis was gallbladder cancer were the focus of the study. We divided the patients according the occurrence of spillage. Furthermore, patients with spillage were divided into two categories according the spillage magnitude. Results: Of the patients, spillage was documented in 32 (29.3%). In 13 patients spillage was considered major. The median follow-up of patients was 36 months, while 35 (32.1%) patients died during the follow-up. Five-year survival of all patients with spillage was not statistically different from the group without spillage. However, the group with major spillage had a statistically worse survival than the rest. A Cox regression analysis including age, gender, level of invasion and spillage category showed that major spillage was independently associated with a worse prognosis.

Ictericia obstructiva secundaria a migración de fragmentos de hepatocarcinoma a la vía biliar / Obstructive jaundice secondary to hepatocellular carcinoma fragments migrated to common bile duct

Obstructive j aundice is a rare presentation of hepatocellular carcinoma (HC), and when it occurs, usually is due to progressive damage from cirrhosis, or extensive tumor infiltration. Tumor growth through the bile duct is being described with increasing frequency as a cause of obstructive j aundice. Rarely, it may be hepatocarcinoma fragments that migrate to the bile duct, obstructing it. We present a case of obstructive jaundice due to migration of fragments of hepatocellular carcinoma to the bile duct in a patient treated 7 years before, for an HC with a curative resection.

La ictericia obstructiva es una presentación poco común en un hepatocarcinoma (HC). Cuando en estos casos existe ictericia, habitualmente se debe a daño progresivo por cirrosis, o a infiltración tumoral extensa. El crecimiento o vaciamiento tumoral hacia la vía biliar se ha descrito ocasionalmente como causa de ictericia obstructiva. En raras ocasiones, puede tratarse de fragmentos de hepatocarcinoma que migran hacia la vía biliar, obstruyéndola. Presentamos un caso de ictericia obstructiva por migración de fragmentos de hepatocarcinoma a la vía biliar, en un paciente tratado 7 años antes por un HC, con resección curativa.

Colesterolosis y cáncer de la vesícula biliar / Association between cholesterolosis and gallbladder cancer

Background: Cholesterolosis is frequently observed in cholecystectomies performed for lithiasis or chronic cholecystitis. Aim: To determine the degree of association between cholesterolosis and gallbladder cancer. Material and Methods: In a prospective study of gallbladder cancer, all gallbladders obtained during cholecystectomies were processed for pathological study, following a special protocol. As part of this study, 23304 surgical samples obtained between 1993 and 2002 were studied, looking for a relationship between cholesterolosis and chronic cholecystitis, adenomas, dysplasia and gallbladder cancer. Results: Seventy nine percent of patients were women. Cholesterolosis was observed in 3,123 cases (13.4 percent). Cholesterolosis was more common in women (14.2 percent) than in men (10.2 percent) (p < 0.001). In the same period, 29 patients were diagnosed with adenomas (0.12 percent), 179 cases with dysplasia not associated with gallbladder cancer (0.8 percent) and 739 gallbladder cancer (3.2 percent). The frequency of cholesterolosis was 13.8 percent in chronic cholecystitis, 13.7 percent in adenomas, 12.1 percent in dysplasias and 1.35 percent in patients with gallbladder cancer (p < 0.01). Of the thirteen cases with gallbladder cancer and cholesterolosis, 10 were early gallbladder carcinomas. Patients with cholesterolosis were 9.2 times less likely to have cancer than those who did not have cholesterolosis. Conclusions: Cholesterolosis has a strong negative association with gallbladder cancer.

[p53 and p27 gene expression in subserosal gallbladder carcinoma]. / Carcinoma subseroso de la vesícula biliar (pT2): valor pronóstico de la expresión de los genes supresores de tumores p53 y p27 en matrices de tejidos.

BACKGROUND: Subserosal carcinoma is the stage that presents the greatest difficulty in the diagnosis therapeutic handling and prognosis evaluation. AIM: To study the expression of p53 and p27 genes in subserosal gallbladder cancer. MATERIAL AND METHODS: One hundred twenty seven tissue samples of subserosal gallbladder cancer (coming from 112 females aged 62+/-13 years and 15 men aged 67+/-17 years) and 50 control samples were selected to construct tissue arrays. p53 and p27 genes were determined by immunohistochemistry. RESULTS: Thirty eight percent of tumors were not detected at the macroscopic examination, 52% and 17% had lymph node and blood vessel involvement, respectively. Fifty six and 46% were positive for p53 and p27, respectively. No association between the expression of both genes and gender, degree of differentiation, lymph node or blood vessel involvement, was observed. Overall five years actuarial survival was 32%. Patients with positive or negative p53 expression had a 22% and 53% survival, respectively (p=0.05). No association between survival and p27 expression was observed. CONCLUSIONS: p53 gene expression is a prognostic factor for subserosal gallbladder cancer.

[Natural history of gallbladder cancer. Analysis of biopsy specimens]. / Desde la displasia hasta el cáncer de la vesícula biliar.

BACKGROUND: There is scarcity of knowledge about the development of gallbladder cancer. AIM: To study the features of development and progression of gallbladder cancer. MATERIAL AND METHODS: Review of histopathological studies of gallbladder obtained in 25,971 cholecytectomies performed in patients aged 45+/- 16 years, 79% females, between 1993 and 2004. Among these, 210 had a dysplasia not associated to cancer and 1,039 had a gallbladder cancer Clinical and morphological parameters of preneoplastic and neoplastic lesions were analyzed. Ninety five percent of patients were followed. RESULTS: All cases of dysplasia were incidental findings. Metaplasia, dysplasia and carcinoma in situ were present in the adjacent mucosa in 66%, 81% y 69% of gallbladder carcinomas, respectively. Twenty five percent of gallbladders studied were carcinomas (mucous carcinoma in 18% and muscular carcinoma in 7%). Ninety two percent of cases had chronic inflammation in the gallbladder wall. Seventy two percent of mucous carcinomas were not detected macroscopically Five years survival of mucous carcinoma was 92%. There was an association between the intensity of the lesion and the age of the patients. The age difference between chronic cholecystitis and gallbladder cancer was 11 years for women and nine for men. CONCLUSIONS: From a morphological standpoint, the period in which a dysplasia becomes a carcinoma is approximately 10 years.

[Immunohistochemical expression of Ki-67 as a marker of proliferation in gallbladder mucosa samples with or without cancer]. / Proliferación celular en la mucosa de la vesícula biliar no tumoral en colecistitis crónicas litiásicas. Expresión de Ki-67 en matrices de tejidos.

BACKGROUND: There is paucity of knowledge on the proliferative features of normal or chronically inflamed gallbladder and the mechanisms of development of gallbladder cancer. AIM: To study the proliferation features of non tumoral gallbladder mucosa through the expression of Ki-67 antigen in tissue micro array analysis. MATERIAL AND METHODS: The immunohystochemical expression of Ki-67 in tissue micro array was studied in 96 samples of non tumoral gallbladder mucosa (coming from 74 females aged 45+/-16 years and 22 males aged 53+/-16 years) and 102 samples of gallbladder cancer (coming from 84 females aged 62+/- 14 years and 18 males aged 70+/- 13 years). RESULTS: The staining index of Ki-67 expression was 19+/-25% (range 096-8996) in samples of non tumoral mucosa and 46+/-29% (range 396-9896) in gallbladder cancer (p <0.01). Ki-67 was expressed in less than 10% of epithelial cells in 55% of non tumoral mucosa samples and 6% of gallbladder cancer samples. Seventy five percent of gallbladder cancer samples had a staining index of more than 20%. An expression of Ki-67 over 20% or 50% was observed in 25% and 15% of non tumoral mucosa samples, respectively. CONCLUSIONS: Non tumoral gallbladder mucosa samples have a high proliferation index, measured using Ki-67 immunohystochemical expression. There is a group of samples with cellular hyper-proliferation that maybe related to the pathogenesis of gallbladder cancer.

Carcinoma subseroso de la vesícula biliar (pT2): valor pronóstico de la expresión de los genes supresores de tumores p53 y p27 en matrices de tejidos / p53 and p27 gene expression in subserosal gallbladder carcinoma

Background: Subserosal carcinoma is the stage that presents the greatest difficulty in the diagnosis therapeutic handling and prognosis evaluation. Aim To study the expression of p53 and p27 genes in subserosal gallbladder cancer. Material and methods: One hundred twenty seven tissue samples of subserosal gallbladder cancer (coming from 112 females aged 62 ± 13years and 15 men aged 67 ± 17years) and 50 control samples were selected to construct tissue arrays. p53 andp27genes were determined by immunohistochemistry. Results: Thirty eight percent of tumors were not detected at the macroscopic examination, 52 percent and 17 percent had lymph node and blood vessel involvement, respectively. Fifty six and 46 percent were positive for p53 and p27, respectively. No association between the expression of both genes and gender, degree of differentiation, lymph node or blood vessel involvement, was observed. Overall five years actuarial survival was 32 percent. Patients with positive or negative p53 expression had a 22 percent and 53 percent survival, respectively (p =0.05). No association between survival and p27 expression was observed. Conclusions: p53 gene expression is a prognostic factor for subserosal gallbladder cancer.

Desde la displasia hasta el cáncer de la vesícula biliar / Natural history of gallbladder cancer Analysis of biopsy specimens

Background: There is scarcity of knowledge about the development of gallbladder cancer. Aim: To study the features of development and progression of gallbladder cancer. Material and methods: Review of histopathological studies of gallbladder obtained in 25,971 cholecytectomies performed in patients aged 45± 16 years, 79 percent females, between 1993 and 2004. Among these, 210 had a dysplasia not associated to cancer and 1,039 had a gallbladder cancer Clinical and morphological parameters of preneoplastic and neoplastic lesions were analyzed. Ninety five percent of patients were followed. Results: All cases of dysplasia were incidental findings. Metaplasia, dysplasia and carcinoma in situ were present in the adjacent mucosa in 66 percent, 81 percent y 69 percent of gallbladder carcinomas, respectively. Twenty five percent of gallbladders studied were carcinomas (mucous carcinoma in 18 percent and muscular carcinoma in 7 percent). Ninety two percent of cases had chronic inflammation in the gallbladder wall. Seventy two percent of mucous carcinomas were not detected macroscopically Five years survival of mucous carcinoma was 92 percent. There was an association between the intensity of the lesion and the age of the patients. The age difference between chronic cholecystitis and gallbladder cancer was 11 years for women and nine for men. Conclusions: From a morphological standpoint, the period in which a dysplasia becomes a carcinoma is approximately 10 years.

Proliferación celular en la mucosa de la vesícula biliar no tumoral en colecistitis crónicas litiásicas. Expresión de Ki-67 en matrices de tejidos / Immunohistochemical expression of Ki-67 as a marker of proliferation in gallbladder mucosa samples with or without cancer

Background: There is paucity of knowledge on the proliferative features of normal or chronically inflamed gallbladder and the mechanisms of development of gallbladder cancer. Aim: To study the proliferation features of non tumoral gallbladder mucosa through the expression of Ki-67 antigen in tissue micro array analysis. Material and methods: The immunohystochemical expression of Ki-67 in tissue micro array was studied in 96 samples of non tumoral gallbladder mucosa (coming from 74 females aged 45±16 years and 22 males aged 53±16 years) and 102 samples of gallbladder cancer (coming from 84 females aged 62± 14 years and 18 males aged 70± 13 years). Results: The staining index of Ki-67 expression was 19±25 percent (range 096-8996) in samples of non tumoral mucosa and 46±29 percent (range 396-9896) in gallbladder cancer (p <0.01). Ki-67 was expressed in less than 10 percent of epithelial cells in 55 percent of non tumoral mucosa samples and 6 percent of gallbladder cancer samples. Seventy five percent of gallbladder cancer samples had a staining index of more than 20 percent. An expression of Ki-67 over 20 percent or 50 percent was observed in 25 percent and 15 percent of non tumoral mucosa samples, respectively Conclusions: Non tumoral gallbladder mucosa samples have a high proliferation index, measured using Ki-67 immunohystochemical expression. There is a group of samples with cellular hyper-proliferation that maybe related to the pathogenesis of gallbladder cancer.

[A pilot experience with a tumor bank]. / Banco de tumores en Chile, su aporte a la investigación: resultados de un proyecto piloto.

BACKGROUND: Despite having the technical facilities and the knowledge, Chile did not have a tumor bank until recently. AIM: To describe the results of the first three years of a tumor bank. MATERIAL AND METHODS: All cases stored in a tumor bank from June 2004 to June 2007 were included. Samples were frozen in isopentane, afterwards in liquid nitrogen and finally transferred to freezers at -80 degrees C. Quality controls with DNA and RNA extraction and immunohistochemistry, were per formed. RESULTS: In the study period, 1239 cases were collected and 79% were malignant tumors. In 78% of cases, samples from the tumor and of normal neighboring tissue, were stored. Twenty six percent of samples were from breast cancer and 22% for digestive tumors. Immunohistochemical expression of vimentin was measured in 30 cases and the expression of Ki67 and p53 in 20 cases. Thirteen of 15 breast cancer samples had expression of estrogen receptors. In 30 cases, DNA and RNA extraction was carried out, amplifying B-globin and B-actin. Moreover RNA was extracted from 63 gastric cancer, 30 colon cancer and gallbladder cancer samples, for specific projects. CONCLUSIONS: The creation of a tumor bank is feasible, preserving samples of high biological quality.

Banco de tumores en Chile, su aporte a la investigación: resultados de un proyecto piloto / A pilot experience with a tumor bank

Background: Despite having the technical facilities and the knowledge, Chile did not have a tumor bank until recently. Aimn: To describe the results of the first three years of a tumor bank. Material and methods: All cases stored in a tumor bank from June 2004 tojune 2007 were included. Samples were frozen in isopentane, afterwards in liquid nitrogen and finally transferred to freezers at -80°C. Quality controls with DNA and RNA extraction and immunohistochemistry, were per formed. Results: In the study period, 1239 cases were collected and 79 percent were malignant tumors. In 78 percent of cases, samples from the tumor and of normal neighaboring tissue, were stored. Twenty six percent of samples were from breast cáncer and 22 percent for digestive tumors. Immunohistochemical expression ofvimentin was measured in 30 cases and the expression of Ki67 an p53 in 20 cases. Thirteen of 15 breast cáncer samples had expression of estrogen receptors. In 30 cases, DNA and RNA extraction was carried out, amplifying B-globin and B-actin. Moreover RNA was extracted from 63 gastríc cáncer, 30 colon cáncer and gallbladder cáncer samples, for specific projects. Conclusions: The creation of a tumor bank is feasible, preserving samples of high biológical quality.

[Microsatellite instability and human papilloma virus genotypes in preneoplastic and neoplastic uterine cervix lesions]. / Inestabilidad microsatelital en lesiones preneoplásicas y neoplásicas del cuello uterino: Correlación con el genotipo del virus papiloma humano.

BACKGROUND: The association between some specific human papilloma virus (HPV) types and cervix cancer is well known. However, the genetic conditions that favor the development of cervical cancer are less well known. AIM: To determine the presence of satellite instability (MSI) in preneoplastic and neoplastic lesions of the cervix and correlate these findings with HPV genotypes. MATERIAL AND METHODS: Biopsy samples of cervical lesions were studied. Sixteen had low grade lesions, 22 had high grade lesions and 28 had an epidermoid cancer. Viral types were identified with polymerase chain reaction, dot-blot hybridization and restriction fragment length polymorphism. MSI was determined using a panel of eight highly informative microsatellites. RESULTS: Microsatellite instability in at least one locus was observed in 91, 56 and 69% of low grade lesions, high grade lesions and epidermoid carcinomas, respectively. MSI-High grade, MSI-Low grade instability and microsatellite stability were observed in 5, 60 and 46% of samples, respectively. Two of three samples with high grade instability had HPV 52 genotype. Other viral subtypes had frequencies that ranged from 78% to 100%, with the exception of HPV16 that was present in only 53% of samples with low grade instability. CONCLUSIONS: Two thirds of biopsy samples from cervical lesions had MSI, mechanism that can be involved in the first stages of cervical carcinogenesis. The low frequency of high grade instability, its association with HPV52 and the low frequency of HPV16 in samples with low grade instability, suggest different coadjutant mechanisms in cervical carcinogenesis.

Inestabilidad microsatelital en lesiones preneoplásicas y neoplásicas del cuello uterino: Correlación con el genotipo del virus papiloma humano / Microsatellite instability and human papilloma virus genotypes in preneoplastic and neoplastic uterine cervix lesions

Background: The association between some specific human papilloma virus (HPV) types and cervix cancer is well known. However, the genetic conditions that favor the development of cervical cancer are less well known. Aim: To determine the presence of satellite instability (MSI) in preneoplastic and neoplastic lesions of the cervix and correlate these findings with HPV genotypes. Material and methods: Biopsy samples of cervical lesions were studied. Sixteen had low grade lesions, 22 had high grade lesions and 28 had an epidermoid cancer. Viral types were identified with polymerase chain reaction, dot-blot hybridization and restriction fragment length polymorphism. MSI was determined using a panel of eight highly informative microsatellites. Results: Microsatellite instability in at least one locus was observed in 91, 56 and 69 percent of low grade lesions, high grade lesions and epidermoid carcinomas, respectively. MSI-High grade, MSI-Low grade instability and microsatellite stability were observed in 5, 60 and 46 percent of samples, respectively. Two of three samples with high grade instability had HPV 52 genotype. Other viral subtypes had frequencies that ranged from 78 percent to 100 percent, with the exception of HPV16 that was present in only 53 percent of samples with low grade instability. Conclusions: Two thirds of biopsy samples from cervical lesions had MSI, mechanism that can be involved in the first stages of cervical carcinogenesis. The low frequency of high grade instability, its association with HPV52 and the low frequency of HPV16 in samples with low grade instability, suggest different coadjutant mechanisms in cervical carcinogenesis

[Osteonecrosis associated with the use of biphosphonates: Case report]. / Osteonecrosis asociada al uso de bifosfonatos: A propósito de un caso clínico.

Biphosphonates reduce the risk of skeletal events and are currently part of standards of therapy in myeloma. Recently, zoledronate and pamidronate have been linked to osteonecrosis of the jaw, specially after surgical dental procedures. We report a 84 year-old man with multiple myeloma who developed spontaneous osteonecrosis of both jaws, after 36 months of therapy with zoledronate with a cumulative dose of 136 mg. We discuss the pathogenic mechanisms, and review the recommendations on prevention and management of this new complication for neoplastic patients under prolonged therapy with biphosphonates.

Frecuencia de los genes de fusión TEL/AML1 y BCR/ABL en pacientes pediátricos con leucemia linfoblástica aguda / Frequency of TEL/AML1 and BCR/ABL fusion genes in children with acute lymphoblastic leukemia

Background: t(12;21) (p12;q22) and t(9;22) (q34;q11) translocations have prognostic significance in acute lymphoblastic leukemia (ALL). The fusion genes TEL/AML1 y BCR/ABL, generated by these translocations, can be easily detected using molecular biology technique. Aim: To study the frequency of TEL/AML1 y BCR/ABL fusion genes in children with ALL. Material and methods: Fifity six children with ALL (age range 1 month- 14 years) were studied, thirty eight from our Temuco Hospital and 18 from the Metropolitan Region. TEL/AML1 y BCR/ABL fusion genes were detected in bone marrow samples using a reverse transcriptase nested polymerase chain reaction (RT-PCR). Results: TEL/AML 1 and BCR/ABL fusion gene transcripts were detected in 13 (23 percent) and 2 (4 percent) children, respectively. No differences in survival were observed between children with positive or negative transcripts for TEL/AML1 fusion gene. However, those positive for BCR/ABL fusion gene, had a significantly lower survival. Conclusions: The frequency of TEL/AML1 and BCR/ABL fusion gene transcripts in these children with ALL is similar to that described by other authors.

Efecto de la fijación en la calidad del ADN: estudio controlado con cinco fijadores / Effect of fixation on DNA quality: controlled study with five fixatives

Antecedentes: Los tejidos fijados y embebidos en parafina son una fuente importante de material para diagnóstico e investigación. La amplificación de ADN desde este tipo de tejidos, mediante reacción en cadena de la polimerasa (PCR), es afectada por el tipo de fijador y los tiempos de fijación empleados. Para determinar el parámetro que mejor se adecue a las condiciones de trabajo de nuestro laboratorio de Patología Molecular, evaluamos el efecto de cinco fijadores sobre la calidad del ADN bajo condiciones controladas. Material y Método: Muestras de mucosa gástrica fueron fijadas, embebidas en parafina y luego procesadas para extracción de ADN empleando un protocolo basado en digestión con proteinasa K. La calidad del ADN se evaluó mediante amplificación de tres fragmentos del gen β-globina (268, 536 y 989 pb). Resultados: No observamos mayores diferencias entre fijadores ni tiempos de fijación en la amplificación de ADN de 268 y 536 pb. No obstante, la amplificación del fragmento mayor (981 pb) se vio alterada al aumentar el tiempo de fijación, a excepción de aquellas muestras fijadas en etanol 70% que presentaron una banda de similar intensidad a la obtenida para muestras control (tejido fresco congelado). Conclusiones: Estos resultados nos proporcionan una pauta para el diseño de experimentos de acuerdo a la calidad del material archivado, optimizando recursos humanos e insumos

Background: Fixed and paraffin-embedded tissues from pathological archives are an important source for research. DNA amplification by polymerase chain reaction (PCR) from those materials is affected by fixatives and fixation time. In order to determine the best condition for our laboratory work, we evaluated the effect of five different fixatives on DNA quality under controlled conditions. Material and Method: Gastric mucosa samples from two patients were fixed, embedded in paraffin and then processed for DNA extraction using a routine method based on proteinase K digestion. DNA quality was evaluated by amplifying three Beta-globin gene fragments (268, 536 and 989 bp). Results: We did not observe major differences among fixatives nor fixation times for 268 and 536 bp fragments but the amplification of the greatest fragment was altered by increasing the fixation time, by excepting those samples fixed in 70% ethanol which present a similar band intensity than control samples (snap-frozen tissue). Conclusions: These results give us a good guideline to design experiments considering the quality of our archival material

Osteonecrosis asociada al uso de bifosfonatos: A propósito de un caso clínico / Osteonecrosis associated with the use of biphosphonates: Case report

Biphosphonates reduce the risk of skeletal events and are currently part of standards of therapy in myeloma. Recently, zoledronate and pamidronate have been linked to osteonecrosis of the jaw, specially after surgical dental procedures. We report a 84 year-old man with multiple myeloma who developed spontaneous osteonecrosis of both jaws, after 36 months of therapy with zoledronate with a cumulative dose of 136 mg. We discuss the pathogenic mechanisms, and review the recommendations on prevention and management of this new complication for neoplastic patients under prolonged therapy with biphosphonates.

Expresión inmunohistoquímica del complejo E-caderina-catenina en cáncer gástrico: Relación con variables clínico-morfológicas y sobrevida de pacientes / Immunohistochemical expression of the E-cadherin-catenin complex in gastric cancer

Background: The E-cadherin/catenin complex plays an essential role in the control of epithelial differentiation. Abnormal expression in tumors correlates with histological grade, advanced stage and poor prognosis. Aim: To evaluate the expression pattern of E-cadherin/catenin complex in gastric carcinoma and analyze their association with tumor clinicopathological features and patient survival. Material and Methods: Inmunohistochemical staining of E-cadherin, alpha and ß-catenin was performed from paraffin specimens of 65 gastric carcinomas. Results: Abnormal expression of E-cadherin, alpha and ß-catenin was demonstrated in 82 percent, 85 percent and 88 percent of gastric carcinomas, respectively. There was a significant correlation between abnormal expression and Lauren pathological classification and depth of infiltration, but not with tumor stage, positive lymph node metastases and survival. Conclusion: Abnormal expression of E-cadherin, alpha and ß-catenin occurs frequently in gastric carcinoma and correlates with histological grade.

[Frequency of TEL/AML1 and BCR/ABL fusion genes in children with acute lymphoblastic leukemia]. / Frecuencia de los genes de fusión TEL/AML1 y BCR/ABL en pacientes pediátricos con leucemia linfoblástica aguda.

BACKGROUND: t(12;21) (p12;q22) and t(9;22) (q34;q11) translocations have prognostic significance in acute lymphoblastic leukemia (ALL). The fusion genes TEL/AML1 y BCR/ABL, generated by these translocations, can be easily detected using molecular biology technique. AIM: To study the frequency of TEL/AML1 y BCR/ABL fusion genes in children with ALL. MATERIAL AND METHODS: Fifty-six children with ALL (age range 1 month- 14 years) were studied, thirty-eight from our Temuco Hospital and 18 from the Metropolitan Region. TEL/AML1 y BCR/ABL fusion genes were detected in bone marrow samples using a reverse transcriptase nested polymerase chain reaction (RT-PCR). RESULTS: TEL/AML 1 and BCR/ABL fusion gene transcripts were detected in 13 (23%) and 2 (4%) children, respectively. No differences in survival were observed between children with positive or negative transcripts for TEL/AML1 fusion gene. However, those positive for BCR/ABL fusion gene, had a significantly lower survival. CONCLUSIONS: The frequency of TEL/AML1 and BCR/ABL fusion gene transcripts in these children with ALL is similar to that described by other authors.

Mutación del gen K-ras en tumores pancreático-biliares / Frequency of K-ras mutation in biliary and pancreatic tumors

Background: The ras gene family (H-ras, N-ras and K-ras) are oncogenes that mutate frequently in human cancer, specially in tumors of the biliary tract and pancreas. Aim: To determine the frequency of K-ras gene codon 12 mutation in pancreatic and biliary tumors. Material and Methods: Samples of 35 gallbladder, 15 ampulla of Vater, 10 biliary tract and 9 pancreatic tumors, were analyzed. The tumor tissue was microdissected from paraffin embedded biopsies. The mutation was detected by a combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Results: Overall, 46% of samples had K-ras gene mutations. Mutation frequency was 80, 56, 50 and 29% for ampulla of Vater, pancreatic, biliary tract and gallbladder tumors, respectively. When compared with the rest, gallbladder tumors had a significantly lower frequency of the mutation. Median survival for biliary tract tumors was 6 months, compared with 65 months for gallbladder tumors (p <0.05). Conclusions: Gallbladder carcinoma had the lower frequency of K-ras mutation, when compared with pancreatic, biliary tract and ampulla of Vater tumors.