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F Michelassi

Publications and source records attributed to F Michelassi.

At least 55 records · Page 3Linked to original sources
PubMed1993

Prospective assessment of functional results after ileal J pouch-anal restorative proctocolectomy.

OBJECTIVE: To document the functional results of 50 consecutive patients who underwent hand-sewn ileal J pouch-anal restorative proctocolectomy for ulcerative colitis between 1988 and 1991 (mean follow-up, 18.1 months; range, 6 to 48 months). DESIGN: Patients recorded their observations daily over 1 week. The patients completed these weekly diaries every 3 months for the first year and then at 18, 24, 36, and 48 months after ileostomy closure. STUDY PARTICIPANTS: Fifty patients (mean age, 31 years; 24 males). SETTING: The University of Chicago (Ill). RESULTS: Stool frequency at 3, 6, 12, and 24 months was 6.3 +/- 2.1, 5.5 +/- 2.4, and 5.1 +/- 1.9, and 5.9 +/- 1.6 per day, respectively, without urgency. Fifty-four percent were perfectly continent; 18% had occasional spotting (one or two leaks per week); 12% had minor leakage (three to seven per week); and 16% had major leakage (more than seven per week). In these three groups, loss of solid feces never occurred in 84%, 88%, and 65% of patients, respectively. Females had more severe incontinence than males, but continence improved over time for both sexes. Twenty-two percent of female patients developed dyspareunia; no males developed impotence, but 19% had retrograde ejaculation. The probability of experiencing pouchitis increased with time from 15% at 6 months to 40% at 12 months, and 50% after 24 months. CONCLUSIONS: These results represent an accurate assessment of patient function after ileal J pouch-anal anastomosis. We encourage the use of a prospective, patient-completed protocol to obtain a realistic assessment of functional results.

Adolescent↗
PubMed1993

Adenocarcinoma complicating Crohn's disease.

We report on 14 cases of intestinal adenocarcinoma complicating Crohn's disease, seven occurring in the small bowel and seven in the large bowel. In both locations, two-thirds of patients were male. The average ages at the time of diagnosis of Crohn's disease and of cancer were similar between the two groups of patients: 28 and 48 years, respectively. The diagnosis of cancer was suspected or obtained preoperatively in only four cases of large bowel cancer; in two patients with large bowel cancer and five with small bowel cancer, the diagnosis was made at laparotomy. In the remaining cases, only careful histologic examination revealed the carcinoma. Six small bowel cancers were located in the ileum, and five colonic cancers were distal to the splenic flexure. Two small bowel and one large bowel cancer were multifocal and had surrounding mucosal dysplasia. All tumors, except one small bowel cancer, underwent resection. Survival correlated with stage of tumor at resection; no patient with regional or distant metastasis survived five years, in comparison with an 83 percent five-year actuarial survival rate of patients with tumor confined to the intestinal wall. Mean survival was six months for patients with small bowel cancer in comparison with 65 months for patients with large bowel cancer, reflecting a tendency toward more advanced lesions in the small bowel cancer group.

Adenocarcinoma↗
PubMed1993

Crohn's disease.

Explore the source record for details and available documents.

Biopsy↗
PubMed1993

Incidence, diagnosis, and treatment of enteric and colorectal fistulae in patients with Crohn's disease.

OBJECTIVE: The authors review their experience, evaluating the incidence and examining the various modalities employed in the diagnosis and treatment of patients with Crohn's disease complicated by fistulae. SUMMARY BACKGROUND DATA: Although common, internal and external fistulae in Crohn's disease may pose challenging problems to the surgeon. METHODS: Of 639 patients who underwent surgical treatment at the University of Chicago between 1970 and 1988 for complications of Crohn's disease, 222 patients (34.7%) were found to have 290 intra-abdominal fistulae. RESULTS: A fistula was diagnosed preoperatively in 154 patients (69.4%), intraoperatively in 60 (27%), and only after examination of the specimen in 8 (3.6%). The fistula represented the primary or single indication for surgical treatment in 14 patients (6.3%) and one of several indications in the remaining patients. Of 165 patients with an abdominal mass or abscess, 69 (41.8%) had a fistula. All patients underwent resection of the diseased intestinal segment; 160 (73.1%) with primary anastomosis and the remaining 62 with a temporary or permanent stoma. The fistula was directly responsible for a stoma in only 16 patients (7.2%) and was never responsible for a permanent stoma. Resection of the diseased bowel achieved en bloc removal of the fistula in 145 cases. Removal of 93 additional fistulae required resection of the diseased bowel segment along with closure of a fistulous opening on the stomach or duodenum (n = 14), bladder (n = 35), or rectosigmoid (n = 44). When the fistula drained through a vaginal cuff (n = 4), the opening was left to close by secondary intention; when the fistula opened through the abdominal wall (n = 46), the fistulous tract was debrided. In the remaining two entero-salpingeal fistulae, en bloc resection of the involved salpinx accomplished complete removal of the fistula. There was a dehiscence of one duodenal and one bladder repair; 14 patients (6%) experienced postoperative septic complications and one patient died. CONCLUSIONS: Fistulae are diagnosed preoperatively in 69% of cases and can be suspected in as many as 42% of patients with an abdominal mass. Fistulae are the primary or single indication for surgical treatment and are directly responsible for a stoma only in a few patients. Treatment, based on resection of the diseased bowel and extirpation of the fistula, can be accomplished with minimal morbidity and mortality.

Adult↗
PubMed1993

A simplified technique for ileal J-pouch construction.

A stapling technique for construction of an ileal J-pouch is presented. The technique is simple, minimizes the chances for pelvic contamination and avoids midpouch enterotomies. By postponing the performance of the apical enterotomy until after the pouch is in the definitive position, the apical enterotomy is placed exactly where needed to facilitate the subsequent ileoanal anastomosis.

Humans↗
PubMed1992

Morbidity and mortality of wide pelvic lymphadenectomy for rectal adenocarcinoma.

This retrospective study was aimed at defining the morbidity and mortality of a radical resection for adenocarcinoma of the rectum complemented by a wide pelvic lymphadenectomy. Twenty-seven consecutive patients with rectal carcinoma who underwent a surgical resection with conventional (Group I) or wide (Group II) pelvic lymphadenectomy were analyzed. Group I consisted of 10 patients (three women and seven men; mean age, 71 years) with tumors between 6 and 14 cm (mean, 10.6 cm) from the anal verge. Group II consisted of 17 patients (eight women and nine men; mean age, 67 years) with tumors between 3 and 14 cm (mean, 9 cm) from the anal verge. The choice of lymphadenectomy in association with colorectal resection was left at the discretion of the surgeon. There were no deaths within 60 days of operation. Mean intraoperative blood loss was the same in the two groups, although three patients (18 percent) required blood transfusions of over two liters during the performance of a wide pelvic lymphadenectomy in comparison with only one (10 percent) during conventional pelvic lymphadenectomy. The rate of early postoperative complications and the average length of postoperative hospital study were each similar between the two groups. After a wide pelvic lymphadenectomy, three (18 percent) patients developed a neurogenic bladder, requiring intermittent self-catheterization, and they all recovered within one, four, and eight months, respectively. Of the 16 males, three from Group I and four from Group II were sexually active and potent before surgical treatment; after recovering from surgery, only two patients from Group I regained their sexual potency. We conclude that the performance of a wide pelvic lymphadenectomy did not increase the intraoperative or early postoperative complication rate, the mean intraoperative blood loss, or the length of postoperative hospital stay. Technical refinements are currently under study to obviate the neurologic long-term complications.

Adenocarcinoma↗
PubMed1992

Prognostic significance of ploidy determination in rectal cancer.

Between 1965 and 1981, 154 patients with potentially curable rectal adenocarcinoma underwent surgical treatment at the University of Chicago Medical Center. In 134 cases, enough histological material was available to perform determinations of DNA content by the cytophotometric method (n = 108), or by the flow cytometric technique (n = 109). In 83 cases, DNA content was analyzed in the same specimen with both techniques, and in 77 of these cases the sections obtained from the paraffin blocks were contiguous. When using flow cytometry, 62% of stage B and 74% of stage C lesions were classified as aneuploid on the basis of a DNA index greater than 1. This correlation was statistically significant (p = 0.002). Patients with diploid tumors had an actuarial five-year survival equal to 62% in comparison with a 46-51% five-year survival for patients with aneuploid tumors. This difference was not statistically significant and it was explained by the tendency for aneuploid tumors to be in an advanced histopathological stage.

Adenocarcinoma↗
PubMed1991

Evidence for a common molecular pathogenesis in colorectal, gastric, and pancreatic cancer.

We examined tissue extracted from 19 gastric, 7 pancreatic, and 23 colorectal carcinoma specimens to determine the comparative incidence of allele loss on chromosomes 5, 17, and 18 and that of KRAS2 point mutations. Chromosome 5 allele loss occurred at the same frequency in all three gastrointestinal tumors (approximately 30%), whereas chromosome 17 and 18 allele losses were seen at a significantly lower frequency in gastric (20%) and pancreatic (0%) malignancies than in colorectal cancer (57%). Point mutations in KRAS2 were seen in 83% of pancreatic and 52% of colon cancers, but not in gastric cancer specimens. In pancreatic tumors, these mutations were always found in the second nucleotide of codon 12. In colorectal cancer, the distribution was more variable, involving the second nucleotide of codon 13 and both the first and second nucleotides of codon 12. These results suggest that inactivation of the adenomatous polyposis coli gene on chromosome 5 may be an initiating step for carcinomas of the stomach and pancreas as well as of the colon, but that the genes involved in tumor progression events may be tissue- or tumor-specific.

Adenocarcinoma↗
PubMed1991

Osteoclast-like giant cell tumor of the pancreas: immunophenotypic similarity to giant cell tumor of bone.

An immunophenotype was performed on an osteoclast-like giant cell tumor of the pancreas using a panel of antibodies to epithelial and leukocyte antigens. Several antibodies to cytokeratin and carcinoembryonic antigen were negative in the tumor. Osteoclast-like cells were positive for CD4, CD13, CD45, CD68, CD71, and vimentin, but negative for lysozyme and HLA-DR. Mononuclear tumor cells were positive for CD4, CD11c, CD13, CD14, CD45, CD68, CD71, HLA-DR, and vimentin, but negative for lysozyme. The phenotype is similar to that previously described for giant cell tumor of bone. The osteoclast-like cell phenotype is also similar to that reported for normal osteoclasts. The findings support a nonepithelial origin for osteoclast-like giant cell tumor of the pancreas, and suggest a derivation similar to giant cell tumor of bone.

Biomarkers↗
PubMed1991

Verification of a new clinicopathologic staging system for colorectal adenocarcinoma.

Rectal adenocarcinoma is said to have a poorer outcome than colon adenocarcinoma when compared on the basis of Dukes' staging. However a new staging system, determined by a multivariate analysis of 147 patients with rectal adenocarcinoma, has revealed three other variables significantly related to outcome. Therefore this study analyzed the authors' experience with colonic carcinoma during the same time period as they had studied for rectal carcinoma to determine whether the new staging system is valid for colon carcinoma as well, and, if so, to compare the outcome of patients with colon and rectal carcinoma on the basis of this new staging. A total of 603 patients with 611 colonic adenocarcinoma were operated on at the University of Chicago Medical Center between 1965 and 1981. Two hundred seventy-nine adenocarcinomas (45.7%) were located proximal to the splenic flexure and 332 (54.3%) were located between the splenic flexure and the rectosigmoid. Four hundred sixty-two patients underwent segmental colectomy, 46 subtotal colectomy, 26 total colectomy, 18 proctocolectomy, 5 abdominal-perineal resection, 1 appendectomy, while 20 had local excision of the tumor through colotomy and 25 had permanent diverting stoma as the only procedure. The operative mortality rate was 6.1% in the whole group, but was only 2.7% in the group of potentially curable patients. Complete follow-up was obtained in all patients. To validate a previous staging system for Dukes' B and C rectal adenocarcinoma, the authors investigated the correlation between 5-year survival for colonic carcinoma patients and all relevant variables that they had considered potentially meaningful in the previous study with rectal adenocarcinoma. The resulting multivariate analysis using Cox regression showed that the four variables found previously to be significantly related to outcome for rectal adenocarcinoma patients (stage, race, tumor morphology, and vascular and/or lymphatic microinvasion) were the only four variables significantly (p less than 0.05) associated with outcome for colonic adenocarcinoma patients. In addition, by using the results of their previous staging system for rectal adenocarcinoma patients, they 'predicted' the 5-year survival rates of the colon adenocarcinoma patients, divided in 16 staging subgroups. In subgroups of at least 15 patients, the rectal staging system predicted the outcome to within 1 to 6 percentage points of the observed outcome of the colonic adenocarcinoma patients. Thus this study validates this staging system, incorporating stage, race, tumor morphology, and microinvasion to predict 5-year survival rate more accurately than Dukes' staging alone for both colon and rectal adenocarcinoma.(ABSTRACT TRUNCATED AT 400 WORDS)

Academic Medical Centers↗
PubMed1991

Primary and recurrent Crohn's disease. Experience with 1379 patients.

Between 1970 and 1988, 1379 patients with Crohn's disease were treated at the University of Chicago. Of these, 639 (mean age, 32.5 years; 322 men, 317 women) required at least one surgical procedure. The most common indications for operation were failure of medical treatment (n = 215, 33%), presence of a fistula (n = 154, 24%), and bowel obstruction (n = 141, 22%). A fistula was the most common intraoperative Crohn's-related complication. In 582 patients (92%), a resection was necessary, with primary anastomosis in 416 (65%), a temporary stoma in 124 (20%), and a permanent stoma in 42 (7%). The remaining 57 patients underwent diverse procedures (stricturoplasty, bypass, and so on). Two patients (0.3%) died. Follow-up data was obtained in 95%. One hundred eighteen patients developed recurrence requiring reoperation. The recurrence rate was 20% at 5 years and 34% at 10 years. The recurrence involved a permanent stoma or a previous anastomosis in 62 patients (afferent limb in 46, efferent in 16). In the 391 patients without previous surgery for Crohn's disease, a covariate analysis was performed to determine those variables significantly associated with recurrence. Variables included demographic data, findings at operation, surgical procedures, and histopathologic characteristics. The analysis revealed that the number of sites involved was the only variable that was significantly associated with the intra-abdominal recurrence rate (p less than 0.001). The annualized risk of recurrence was 1.6% for patients with single-site involvement and 4% for those with multiple-site involvement. Perineal disease was associated with a significantly higher risk of local recurrence than any other site (p less than 0.02). A subanalysis of 236 patients with single-site involvement but no previous operation allowed us to study the influence of site on indications for surgery and type of operative procedure. Failure of medical treatment was the most common indication for all sites. In contrast the site involved influenced the procedure: resection and primary anastomosis was feasible in 88% of jejunoileal and terminal ileal cases and a temporary ileostomy was necessary in only 12%. No patients with small bowel localization required a permanent stoma. A resection with primary anastomosis was feasible in only 32% of patients with colonic disease. The remaining two thirds of patients required either a temporary or a permanent stoma. It is concluded that multisite involvement is associated with 2.5 times the rate of recurrence of single-site disease, while the presence of perineal disease has a significantly higher incidence of local recurrence.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Karyometric features in nuclei near colonic adenocarcinoma. Statistical analysis.

The normal mucosa adjacent to colonic adenocarcinoma (marginal or transitional mucosa) has been shown to have subtle alterations of architecture, surface glycoproteins and proliferative activity. To evaluate possible changes in nuclear configurations in this marginal mucosa, a large set of cytometric features was evaluated using a computer-assisted video analysis system. Preliminary statistical analysis of the measurements identified six nuclear features useful for discriminating marginal mucosa nuclei from normal (control) mucosa nuclei: total optical density (OD), nuclear area, chromatin texture (from gray value cooccurrence matrix), chromatin coarseness, average OD of nuclear staining and peripheral tendency of the chromatin in the nucleus. An analysis of variance revealed that both patient-to-patient and gland-to-gland variation would limit the usefulness of any one feature as a screening tool. As a group, however, these six features should be investigated further as markers of preneoplastic changes in histologically normal-appearing mucosa.

Adenocarcinoma↗
PubMed1991

Evidence for a new tumor-suppressor gene involved in gastrointestinal malignancies.

Inactivation or loss of tumor-suppressor genes is believed to lead to the development or progression of malignancies. To determine whether a tumor-suppressor gene is located on chromosome 8, DNA was extracted from tumor and normal tissue of colorectal, gastric, and pancreatic specimens, and allele loss was investigated by Southern hybridization techniques with the chromosome 8 probe D8S7. Twenty-five percent of pancreatic carcinomas, 50% of gastric carcinomas, and 50% of colorectal carcinomas were found to have lost an allele on chromosome 8. These findings suggest the presence of a tumor-suppressor gene on chromosome 8, which is involved in colorectal carcinoma, gastric carcinoma, and pancreatic carcinoma. Definition of the frequency with which this tumor-suppressor gene is involved in gastrointestinal malignancies will await the study of many patients who are classified as informative and the use of multiple probes for chromosome 8.

Adenocarcinoma↗
PubMed1990

Karyometric marker features in normal-appearing glands adjacent to human colonic adenocarcinoma.

The expression of nuclear marker features in normal-appearing tissue adjacent to colonic adenocarcinoma was investigated. Formalin-fixed, paraffin-embedded tissue sections of colon from 9 patients with adenocarcinoma and from 9 normal controls were cut 4 microns thick, Feulgen stained, and measured by a cell image analysis system using a Matrox MVP-AT/NP imaging board. Thirty nuclei in the tumor region, 30 nuclei 2 mm into the histologically normal-appearing distal margin, and the same number at 5, 10, 20, and 50 mm into the margin were measured for each patient. An additional 30 nuclei were recorded from 9 patients each free from colonic disease. Nuclear features were selected to discriminate between tumor nuclei and nuclei from normal control subjects and between nuclei measured in the histologically normal-appearing margin next to the tumor and control nuclei. Eight micromorphometric measures were found to be statistically significantly different in nuclei measured in the margin site, including features describing staining density (total absorbance, average absorbance 20% below mean, average absorbance 20% above mean) chromatin texture (cooccurrence matrix, run length, and peripheral tendency) and nuclear area. The category differences are statistically highly significant.

Adenocarcinoma↗
PubMed1990

Expression of ras oncogene p21 protein in esophageal squamous cell carcinoma.

In order to investigate the value of ras oncogene expression as a prognostic indicator in esophageal squamous cell carcinoma, we evaluated the level of ras oncogene protein product (p21) in 52 specimens resected between 1977 and 1986. All patients were followed until death or for at least 2 years. Pathology slides and archival paraffin blocks were retrieved for confirmation of the original diagnosis, study of histopathologic features, and measurement of p21 content. P21 titers were obtained using the RAP-5 monoclonal antibody in a semiquantitative immunohistochemical assay. Titer was expressed as the highest dilution of antibody giving definitive staining using the avidin-biotin peroxidase method. Ras oncogene was expressed in 88.5% of the specimens. We did not find a significant correlation between ras expression and any of a variety of clinical and histopathologic prognostic parameters. Although patients' median survival after resection of specimens with ras oncogene expression was less than half the median survival after removal of tumors without such expression, this difference was not statistically significant. Further prospective investigations are needed to assess the role of ras oncogene evaluation in clinical practice.

Adult↗
PubMed1990

Pancreatic microcystic adenoma coexistent with pancreatic ductal carcinoma. A report of two cases.

We report two cases of microcystic (glycogen-rich) adenoma of the pancreas with coexistent pancreatic adenocarcinoma. Both patients presented with an epigastric mass. On laparotomy, each had two separate pancreatic tumors. The benign tumors were composed of small cysts with a flattened to cuboidal glycogen-rich epithelium. Both malignant tumors were composed of mucinous epithelium and showed positive staining for CEA and Leu-M1. Although pancreatic microcystic adenoma and ductal adenocarcinoma are believed to arise from different precursor cells, the association reported here suggests a common predisposition to both tumors. Careful examination of the pancreas is warranted in cases of microcystic adenoma to rule out a possible coexistent pancreatic carcinoma.

Adenoma↗