Anatomofisiología de la continencia y la defecación / Anatomy and physiology of continence and defecation

Continencia y defecación son 2 funciones trascendentales en el género humano, de tal manera que su alteración, traducida como incontinencia anal y/o estreñimiento, puede afectar gravemente a la calidad de vida. En este trabajo se analizan las estructuras anatómicas y los mecanismos fisiológicos admitidos como condicionantes del correcto desarrollo de ambas funciones, y se reconoce de forma generalizada que existen todavía muchos puntos no aclarados en esta compleja, y a veces paradójica, estructura/función del cuerpo humano (AU)

Continence and defecation are two essential functions in humans. Any alteration resulting in anal incontinence and/or constipation can severely impair the patient's quality of life. This study analyzes the anatomical structures and physiologic mechanisms accepted as factors involved in the correct development of both functions, while recognizing that there are still many unclear issues within this complex and sometimes paradoxical structure/function of the human body (AU)

[Microsatellite instability predicts better outcome in colorectal cancer patients]. / La inestabilidad de microsatélites predice un mejor pronóstico en los pacientes intervenidos de carcinoma colorrectal.

BACKGROUND AND OBJECTIVE: Two different pathways for the development of tumor have been described in colorectal carcinoma: the chromosomic instability, raised by suppressor genes and proto-oncogene alterations, and the microsatellite instability (MSI), caused by alterations in DNA repairing genes. PATIENTS AND METHOD: The frequency and the clinical meaning of the microsatellites instability pathway were determined in a consecutive prospective cohort of 106 patients who underwent surgical resection of colorectal carcinoma by a single surgeon. Microsatellite instability determination was established according to the criteria proposed by the National Cancer Institute in 1998. RESULTS: 9.4% of patients had a high instability and it was low in 11.3%; both groups displayed different clinico-pathological characteristics (age, sex, tumor site and histologic type). In the multivariant analysis of overall survival and disease free survival, high instability exhibited prognostic value independent of the rest of variables evaluated (p < 0.0001). CONCLUSIONS: The genetic alterations giving rise to microsatellite instability lead to a better prognosis in patients with colorectal cancer.

La inestabilidad de microsatélites predice un mejor pronóstico en los pacientes intervenidos de carcinoma colorrectal / Microsatellite instability predicts better outcome in colorectal cancer patients

FUNDAMENTO Y OBJETIVO: En el carcinoma colorrectal se describen 2 vías genéticas diferentes implicadas en la génesis del tumor: la inestabilidad cromosómica, debida a la alteración de genes supresores o protooncogenes, y la inestabilidad de microsatélites, originada por alteraciones en los genes reparadores del ADN. PACIENTES Y MÉTODO: En este estudio se determina la frecuencia y el significado clínico de la vía de la inestabilidad de microsatélites en una cohorte prospectiva consecutiva de 106 pacientes intervenidos por carcinoma colorrectal por un mismo cirujano. Para la determinación de la inestabilidad de microsatélites se han seguido los criterios propuestos por el National Cancer Instituteen 1998. RESULTADOS: El 9,4% de los pacientes muestra una alta inestabilidad y el 11,3% una inestabilidad baja. Ambos grupos presentan diferentes características clínico patológicas (edad, sexo, localización del tumor y tipo histológico). En el análisis multivariante de la supervivencia global y de la supervivencia libre de enfermedad, la alta inestabilidad presenta un valor pronóstico independiente del resto de las variables clínico patológicas analizadas (p < 0,0001). CONCLUSIONES: La alteración genética que supone la alta inestabilidad de microsatélites confierea los pacientes con cáncer colorrectal un mejor pronóstico

BACKGROUND AND OBJECTIVE: Two different pathways for the development of tumor have been described in colorectal carcinoma: the chromosomic instability, raised by suppressor genes and protooncogene alterations, and the microsatellite instability (MSI), caused by alterations in DNA repairing genes. PATIENTS AND METHOD: The frequency and the clinical meaning of the Microsatellites instability pathway were determined in a consecutive prospective cohort of 106 patients who underwent surgical resection of colorectal carcinoma by a single surgeon. Microsatellite instability determination was established according to the criteria proposed by the National Cancer Institute in1998. RESULTS: 9.4% of patients had a high instability and it was low in 11.3%; both groups displayed different clinico-pathological characteristics (age, sex, tumor site and histologic type). In the multivariant analysis of overall survival and disease free survival, high instability exhibited prognostic value independent of the rest of variables evaluated (p < 0.0001). CONCLUSIONS: The genetic alterations giving rise to microsatellite instability lead to a better prognosis in patients with colorectal cancer

[Anatomy and physiology of continence and defecation]. / Anatomofisiología de la continencia y la defecación.

Continence and defecation are two essential functions in humans. Any alteration resulting in anal incontinence and/or constipation can severely impair the patient's quality of life. This study analyzes the anatomical structures and physiologic mechanisms accepted as factors involved in the correct development of both functions, while recognizing that there are still many unclear issues within this complex and sometimes paradoxical structure/function of the human body.