Juvenile polyposis–a precancerous condition

Abstract

Juvenile polyposis-a precancerous conditionClinical and pathological findings in 87 patients with juvenile polyposis have been reviewed; 1032 polyps were available from 80 of these patients; 840 were typical spherical juvenile polyps whereas 169 differed in being multilobulated or showing a villous configuration; 79 (46.7%) of the latter contained foci of epithelial dysplasia whereas only 76 (9.0%) of the typical juvenile polyps were dysplastic. The series also included 21 adenomas and two hyperplastic (metaplastic) polyps. The demonstration of dysplasia provides a histogenetic mechanism for the evolution of colorectal cancer from hamartomatous polyps; 18 juvenile polyposis patients have developed colorectal cancer at a mean age of 34 years (range 15-59). The clinical outcome was generally poor. No clinical or pathological distinction could be made between polyposis patients with and without colorectal cancer. Thus, the development of cancer in juvenile polyposis appears to be a random event. A working definition of juvenile polyposis is provided:(1) more than five juvenile polyps of the colorectum; and/or (2) juvenile polyps throughout the gastrointestinal tract; and/or (3) any number of juvenile polyps with a family history of juvenile polyposis. It is suggested that the condition should be treated as seriously as familial adenomatous polyposis except that regular colonoscopic surveillance may obviate the need for prophylactic colectomy.

Prospective comparison of family medical history with personal genome screening for risk assessment of common cancers

“…Participants' medical and family histories were then re-examined for evidence of hereditary risk. Hereditary risk was assigned if the subject or family met the Amsterdam II or Revised Bethesda Guidelines for Lynch syndrome; 20,21 or met accepted criteria for familial adenomatous polyposis or attenuated FAP, 22,23 MYH-associated polyposis, 24 juvenile polyposis syndrome, 25 or Peutz-Jeghers syndrome 18 (Supplementary Table 2). Research participants or family members who carry a known germline mutation in a colorectal cancer-predisposition gene were classified as hereditary risk.…”

Juvenile polyposis syndrome with extraintestinal anomalies: report of a rare case with review of literature

“…The sporadic type JPS is more common, occurring in 66% and 33% have a positive family history. 6 In a study 85% cases of JPS were diagnosed in the first and second decade of life; 98% patients had polyps in colon, 14% in stomach, 2% in duodenum and 7% in jejunum and ileum. 7 Juvenile polyps range from few millimeters to 3 centimetres in diameter, covered by columnar epithelium having mucus filled glands in an abundant lamina propria having inflammatory cells.…”

“…9 Patients with JPS have a higher risk of developing colorectal cancer with an incidence of 20.7% with mean age of 34 years and a cumulative cancer risk of 68% by 60 years of age. 6 The pathogenesis of carcinomatous change in hamartomatous polyps is elucidated unlike that of adenomatous polyps in which malignant transformation progresses through the adenoma- carcinoma sequence via gatekeeper/caretaker defect. The hypothesis proposed for hamartoma-carcinoma sequence is a landscaper defect in which stromal elements alter the local environment and promote epithelial dysplasia and carcinoma.…”

Polipose juvenil: relato de 2 casos

“…Esta síndrome afeta de 1 em 100.000 (6) a 1 em 160.000 (7) pessoas e costuma se manifestar entre 4 e 14 anos de idade. O seu diagnóstico é feito quando os seguintes critérios clínicos são encontrados (8) : mais de 5 pólipos juvenis no cólon ou no reto, ou; pólipos juvenis em outras áreas do trato gastrintestinal, ou; qualquer número de pólipos juvenis e uma história familiar positiva. A paciente 1 preenche dois critérios: mais de 50 pólipos juvenis e história familiar positiva.…”

“…Em 2004, um total de 141 pacientes foram testados para mutação no gene SMAD4 em 6 estudos (Friedl et al (12) , WoodfordRichens et al (13) , Howe et al (14,15) , Roth et al (16) , Kim et al (17) ) 32 (22,7%) pacientes apresentaram mutação positiva. Esta mutação provoca perda da inibição do crescimento celular e inibição da apoptose (alteração do fator de crescimento transformador beta -TGF â) com crescimento do componente mesenquimal o que resulta em displasia epitelial e progressão neoplásica (8) . A perda dos receptores do TGF â ocorre, com freqüência, em tumores humanos, proporcionando uma vantagem proliferativa às células tumorais (1) .…”