Cyrus E. Rubin

DNA aneuploidy in colonic biopsies predicts future development of dysplasia in ulcerative colitis

The objective of the present study was to determine whether abnormal epithelial DNA content (aneuploidy) in colonic biopsy specimens from ulcerative colitis (UC) patients correlated with and predicted histological progression to dysplasia. Aneuploidy was absent in 20 low-cancer risk patients. In 81 high-cancer risk patients aneuploidy correlated significantly with the severity of histological abnormality (negative, indefinite, dysplasia, or cancer). Statistically our data suggest that many more biopsy specimens than are usually taken are needed to detect focal dysplastic lesions. Prospective study of 25 high risk patients without dysplasia revealed 5 with aneuploidy, all of whom progressed to dysplasia in 1-2.5 years, whereas 19 patients without aneuploidy did not progress to either aneuploidy or dysplasia within 2-9 years. Our data indicate that aneuploidy in mucosal biopsy specimens correlates with histological grade and identifies a subset of patients without dysplasia who are more likely to develop it. It was concluded that more frequent and extensive colonoscopic surveillance of this minority subset of high risk patients and less frequent surveillance in the remaining majority may reduce cost and detect more curable lesions.

Flow-cytometric and histological progression to malignancy in Barrett's esophagus: Prospective endoscopic surveillance of a cohort

To determine whether or not flow-cytometric evidence of aneuploidy and increased G2/tetraploid fractions predispose to neoplastic progression in Barretts esophagus, 62 patients with Barretts esophagus were evaluated prospectively for a mean interval of 34 months. Nine of 13 patients who showed aneuploid or increased G2/tetraploid populations in their initial flow-cytometric analysis developed high-grade dysplasia or adenocarcinoma during follow-up; none of the 49 patients without these abnormalities progressed to high-grade dysplasia or cancer (P less than 0.0001). Neoplastic progression was characterized by progressive flow-cytometric and histological abnormalities. Patients who progressed to high-grade dysplasia and carcinoma frequently developed multiple aneuploid populations of cells that were detectable flow-cytometrically. Similarly, patients appeared to progress through a phenotypic sequence that could be recognized histologically by the successive appearance of Barretts metaplasia negative for dysplasia, abnormalities in the indefinite/low-grade dysplasia range, high-grade dysplasia, and eventually adenocarcinoma. These and prior results suggest that neoplastic progression in Barretts esophagus occurs in a subset of patients who have an acquired genomic instability that generates abnormal clones of cells, some of which have aneuploid or increased G2/tetraploid DNA contents. With continued genomic instability, multiple aneuploid subclones may evolve, one of which may ultimately acquire the ability to invade and become an early carcinoma. The combination of histology and flow cytometry can be used to identify a subset of patients with Barretts esophagus who merit more frequent endoscopic surveillance for the early detection of high-grade dysplasia or carcinoma.

Mutations in the p53 gene: An early marker of neoplastic progression in ulcerative colitis

BACKGROUND/AIMS In long-term extensive ulcerative colitis, aneuploidy occurs earlier and loss of heterozygosity for p53 (p53 LOH) later during histological progression towards carcinoma. This study determined the time of onset of p53 mutation in this progression. METHODS We developed a rapid, sensitive screening assay for p53 mutations at codon 248. The geographic distribution of this p53 mutation was mapped in two fresh colectomy specimens with mutations of codon 248 (1 cancer, 1 dysplasia) and correlated with patterns of clonal expansion, histological progression, and allelic loss. Numerous samples from throughout both colons were analyzed (216 for histology, 142 for DNA content, 104 for mutation, and 41 for p53 LOH). RESULTS p53 mutation correlated highly with histological grade and was distributed more extensively than p53 LOH. Mutation, but not LOH, was also found in diploid, nondysplastic colonic mucosa adjacent to dysplastic areas. CONCLUSIONS These findings suggest that p53 mutation appears to be an early genetic event that precedes p53 LOH. The very close correlation of p53 mutation with aneuploidy (P > 0.0001) emphasizes the role of normal p53 at the G1 checkpoint to help prevent entry of genetically damaged cells into the cell cycle.

Endoscopic biopsy can detect high-grade dysplasia or early adenocarcinoma in Barrett's esophagus without grossly recognizable neoplastic lesions

There is uncertainty regarding the value of endoscopic biopsy surveillance in Barretts esophagus because, in retrospective studies, some patients with high-grade dysplasia in endoscopic biopsy specimens have had unexpected advanced adenocarcinoma discovered at the time of esophageal resection. We compared the accuracy of preoperative endoscopic biopsy diagnoses with the final pathologic diagnoses in esophagectomy specimens in 4 patients who had both high-grade dysplasia and intramucosal carcinoma and 4 other patients who had only high-grade dysplasia preoperatively. The histologic lesions in all 8 patients were documented in intact mucosa with no gross evidence of neoplasia by endoscopy. The preoperative diagnoses were defined with an endoscopic biopsy protocol in which specimens were taken with large-channel biopsy forceps at least every 2 cm throughout the length of Barretts epithelium. Final pathologic diagnoses derived from detailed analysis of the resected specimens confirmed high-grade dysplasia without carcinoma in 4 patients and intramucosal carcinoma in 2 patients. The remaining 2 patients with a preoperative diagnosis of intramucosal carcinoma had focal submucosal invasion by carcinoma in the resected specimens, but no involvement of the muscularis propria or adventitial lymph nodes. Because the natural history of high-grade dysplasia is not known, the decision to operate on patients with this lesion must be carefully weighed and individualized for each patient. Two of our patients who underwent esophageal resection for high-grade dysplasia without cancer died, one immediately postoperatively and the other 9 mo later after a postoperative stroke. Once intramucosal carcinoma is documented, surgery should be considered if the patient is an acceptable operative risk. We conclude that systematic preoperative endoscopic biopsy of intact mucosa in Barretts esophagus can correctly detect high-grade dysplasia, either alone or in combination with early, treatable adenocarcinoma.

Studies of celiac disease. I. The apparent identical and specific nature of the duodenal and proximal jejunal lesion in celiac disease and idiopathic sprue.

Summary In order to investigate systematically the possible relationship between celiac disease and idiopathic sprue, 230 suction biopsies of the duodenum and proximal jejunum were taken from 26 patients with celiac disease, 16 patients with idiopathic sprue, and 73 controls (3 months to 77 years old). The controls consisted of normals, patients with other types of malabsorption, and persons with situations which might theoretically cause an intestinal mucosal abnormality. A small diameter, highly flexible instrument was developed which enabled biopsies to be taken with equal facility from infants and adults. The absorptive surface of the fresh, unsectioned specimen was studied microscopically during fixation. The controls were covered with delicate villi, each of which contained numerous villous capillaries, whereas the abnormal specimens were more or less bald and had a disorganized, sparse vasculature. These findings were confirmed by the appearance of the tissue sections. The most constant diagnostic feature was the reduction in epithelial surface, with varying degrees of blunting or loss of villi. Infiltration of the lamina propria with round cells and abnormalities of the epithelial cells at the luminal surface were frequent but not invariable findings. Perfectly oriented serial sections were evaluated histologically by three observers independently and without clinical foreknowledge. A fourth observer evaluated them by a quantitative technique. This histologic interpretation and obj ective quantitativn agreed with the proved clinical diagnosis in every instance. The appearance of the proximal intestinal abnormality in celiac disease and idiopathic sprue is identical. The celiac-sprue lesion is apparently specific for it was not found in any of the controls. The normalcy of the ileal mucosa was demonstrated in 1 adult celiac patient and 1 idiopathic sprue patient, despite the fact that the proximal j ej unal biopsies in both cases were severely abnormal. The characteristic lesion in the duodenum and proximal jejunum in celiac disease and idiopathic sprue is probably pathognomonic.

Relation of Giardiasis to Abnormal Intestinal Structure and Function in Gastrointestinal Immunodeficiency Syndromes

Seven of 8 patients with hypogammaglobulinemia and gastrointestinal symptoms were infected with Giardia lamblia. This parasite was not detected by multiple stool examinations in 4 of the 7 infected patients but was diagnosed correctly by small intestinal biopsy. Abnormalities of the small intestinal mucosa were found in all 8 patients. Two patients had nodular lymphoid hyperplasia and 3 the flat lesion of hypogammaglobulinemic sprue. The remaining 3 patients had mixed lesions; that is, the lesions varied both in severity of the villus abnormality and in the frequency of lymphoid nodules. All patients lacked plasma cells in the lamina propria. Because of the variation in the severity of the small intestinal abnormalities within individual patients, multiple small bowel biopsies were needed to evaluate the effects of treatment on mucosal morphology. After eradication of Giardia lamblia in 7 patients, the abnormalities in villus structure returned towards normal in all. No change occurred after a course of metronidazole (Flagyl) in the 1 patient who had a severe intestinal lesion but no evidence of giardiasis. Four patients with steatorrhea and giardiasis gained weight and their fecal fat excretion returned to normal. Diarrhea disappeared after treatment in the remaining 3 patients.

Small intestinal biopsy

Abstract A practical approach to the interpretation of peroral small intestinal biopsy specimens is presented. Biopsy technique and tissue handling are described. Interpretation of normal and abnormal biopsy specimens is discussed. A practical classification of abnormal small intestinal biopsies is presented and illustrated.

C-Ki-ras mutations in chronic ulcerative colitis and sporadic colon carcinoma

Mutations in the first exon of the c-Ki-ras protooncogene were analyzed in carcinomas and dysplasias from patients with sporadic colon cancer and chronic ulcerative colitis by a combination of histological enrichment, cell sorting, polymerase catalyzed chain reaction, and direct sequencing. In contrast to sporadic colon carcinomas, where 52% (11 of 21) contained mutations in codon 12, only 1 of 28 samples of ulcerative colitis associated carcinoma or dysplasia contained a c-Ki-ras mutation, despite the presence of aneuploid cell populations. These results suggest that a different genetic pathway for tumor progression may exist between sporadic colon carcinoma and carcinomas arising in chronic ulcerative colitis.

Soy Protein-Another Cause of the Flat Intestinal Lesion

This is a prospective study of the pathogenesis of a violent gastrointestinal reaction to soy protein in an infant. Within 24 hr of changing this 6-week-old infants formula to soy milk, he developed sequentially: fever, leukocytosis, cyanosis, vomiting, massive blood-tinged mucoid diarrhea, dehydration, and metabolic acidosis. All symptoms disappeared after discontinuing soy milk. At 6 and 10 months the patient was given a single test feeding of soy milk formula and soy protein isolate respectively. All symptoms recurred promptly. The previously normal jejunal mucosa became acutely inflamed and flat (villi disappeared). The patient recovered completely within 48 hr and villi regenerated within 4 days. Soy lecithin, gluten, and cows milk neither produced symptoms nor altered intestinal structure. Total hemolytic complement did not change after soy milk exposure nor did circulating eosinophils increase, despite leukocytosis with shift to the left. This is the first documentation of a reversible flat jejunal lesion caused by feeding soy protein to a susceptible infant.

Human rectal mucosa: proctoscopic and morphological changes caused by laxatives.

To determine whether laxatives alter the proctoscopic and morphological appearances of the human rectum, 10 normal subjects were studied prospectively, and the following manipulations were assessed in a randomized, blinded manner: no treatment; oral mannitol to induce diarrhea; isotonic saline enema; Fleets Phospho-Soda enema; and bisacodyl (Dulcolax), 10 mg, by enema or suppository. The rectal mucosa after mannitol-induced diarrhea, or after saline enema could not be distinguished from untreated rectum by proctoscopy, light microscopy, or scanning electron microscopy. Fleets enema, and bisacodyl invariably changed proctoscopic appearances, and frequently altered light and scanning microscopic aspects. Both Fleets enema and bisacodyl caused sloughing of surface epithelium. In addition, bisacodyl decreased the uptake of hematoxylin and eosin by crypt epithelial cells so that the affected cells had a partially erased appearance (16 of 25 biopsies examined by light microscopy). The lamina propria of 3 of these 25 biopsies contained polymorphonuclear cells. Transmission electron microscopy revealed that the abnormal crypt epithelial cells contained fewer cytoplasmic organelles and less nuclear chromatin. All lesions resolved within 7 days. Fleets enema and bisacodyl by rectum may mislead the proctologist and the pathologist by altering normal rectal mucosa.