Clinical Aspects and Management of Hereditary Non-Polyposis Colorectal Cancer (HNPCC)

Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomical dominant trasmitted disease phenotypically defined according to the “Amsterdam criteria” as follows: at least 3 affected relatives, one of whom first degree relative of other two, at least two successive generations affected. Important cardinal features are:

1 prevalent proximal location of cancers (above splenic flexure);

2 multiple synchronous or methachronous large bowel cancers;

3 early age of onset (<50 years);

4 presence of extracolonic cancers (endometrium, stomach, urinary tract, skin).

The treatment is essentially surgical and total colectomy with ileo-rectum anastomosis is already proposed as standard procedure with annual endoscopic examination of retained rectum. The screening of individuals at risk, so determined by the analysis of pedigree or the results of molecular tests, must be performed every 1-2 years by colonoscopy starting around the age of 25 years. In this review are described and analysed the spectrum of the disease with particular attention to the frequency and characteristics of extracolonic cancers. Moreover, the guidelines of the surveillance and screening are reported following the data of the literature and as proposed by the International Collaborative Group (ICG-HNPCC).

The colorectal malignant polyp: scoping a dilemma

Colorectal adenomas containing invasive carcinoma represent the majority of early colorectal cancers. The malignant polyp carries a significant risk of lympho-haematic metastasis and mortality due to the penetration of cancerous cells into the submucosal layer. The therapeutic dilemma is whether to perform endoscopic or surgical resection. A thorough assessment of the endoscopic, histological and clinical variables is needed to unravel the best treatment for each patient. In particular, a unique staging of such lesions, based on certain histopathological features, has been deeply implicated in the therapeutic choice. Aim of this article is to review the main endoscopic, histological and clinical features of the malignant polyp in order to propose a systematic management of this lesion.

Endoscopic follow-up after colorectal cancer resection: an Italian multicentre study

BACKGROUND

Endoscopic follow-up is advised in patients operated for colorectal cancer due to a high risk for both metachronous colorectal cancer and adenomas. Such issue has been scarcely addressed in Italy. This study aimed to evaluate the incidence of neoplastic lesions at a scheduled endoscopic follow-up and to identify the patients at higher risk of recurrence.

METHODS

Colorectal cancer patients diagnosed in the three participating hospitals (one North, one Centre and one South Italy) were scheduled for colonoscopies at 1, 3 and 5 years after surgery. Incidence of adenomas, advanced adenomas and colorectal cancer was assessed in all patients. Neoplastic incidence in patients with and without synchronous lesions at entry was also compared.

RESULTS

Overall, 318 consecutive patients were prospectively enrolled including 108 (34%, group A) with a synchronous lesion and 210 (group B) without it. A cumulative neoplastic incidence of 20.1, 32.4 and 44% was observed at 1, 3 and 5 years of follow-up, respectively. The cumulative incidence of all the lesions was 70% in group A and 30.2% in group B at 5-year follow-up, being 39.5 and 15.5% after excluding the lesions detected at 1-year examination. A neoplastic lesion was detected more frequently in group A at 1year (30.5% versus 14.7%; p = 0.0013), 3 years (21.4% versus 7.6%; p = 0.0008) and at 5years (18.1% versus 7.8%; p = 0.02).

CONCLUSIONS

Our data showed that the incidence of adenomas in patients operated for colorectal cancer is fairly high. Colorectal cancer patients with synchronous lesions are at higher risk of neoplastic recurrence at follow-up as compared to those without them.

Gastric metaplasia and small bowel ulcerogenesis in a case of ulcerative jejunitis not related to celiac disease

The possible relationship between gastric metaplasia and ulcerative lesions in an unusual case of ulcerative jejunitis not related to celiac disease and with extensive gastric metaplasia is discussed. Previous studies have described gastric metaplasia in duodenal ulcers on the basis of endoscopic data, and some authors maintain that acid secretion in metaplastic mucosa could represent a pathogenetic factor of ulcerogenesis, with a self-amplifying mechanism. In the absence of functional evidence, we could provide data, in a case of ulcerative jejunitis, about morphologic signs of acid secretion in gastric metaplastic epithelium using an antibody against HMFG-1, a good marker of acid-secreting fundic cells. Metaplastic areas demonstrated a focal positivity for HMFG-1, and these finding are suggestive of local acid secretion.

Clinical identification and long-term surveillance of 22 hereditary non-polyposis colon cancer Italian families

OBJECTIVE

To assess the efficacy of a hereditary non-polyposis colon cancer (HNPCC) identification and surveillance policy.

METHODS

Familial clustering of colorectal cancer (CRC) and extracolonic cancers (ECs) was investigated in 1520 consecutive CRC patients and relatives. HNPCC was identified by Amsterdam criteria, and individuals at risk were offered biennial colonoscopy and other examinations, starting from age 25 years.

RESULTS

Twenty-two HNPCC families were identified. The CRC prevalence was 27.8% (121/435), decreasing from 59.4% in the first generation to 24.4% and 8% in the second and third generation, respectively. Twenty-nine patients had multiple CRC and 34 patients (in 12 families) had ECs.A total of 199/331 at-risk individuals accepted surveillance. The mean follow-up was 48+/-32 months. CRCs were detected at first surveillance in four out of 199 surveilled individuals (2%); in two surveilled individuals (1%), three CRCs developed during follow-up. The overall CRC incidence was 7/199 (3.5%) in surveilled individuals and 5/132 (3.7%) in unsurveilled individuals. CRCs were less advanced in surveilled than in unsurveilled patients. Eleven individuals had 22 adenomas (one with high-grade dysplasia). Three individuals had adenomas at first surveillance; two of them and eight more individuals during surveillance. Seven surveilled individuals and six unsurveilled individuals, all belonging to families with a history of EC, had EC during the study period. All patients with CRC detected by surveillance are alive. One of the unsurveilled patients who had CRC died 18 months after the diagnosis.

CONCLUSIONS

Data confirm the importance of the family history collected in each patient with CRC for identification of HNPCC and support the efficacy of repeated colonoscopies for early diagnosis and prevention of CRC in at-risk members. Reasons for surveillance failure could be an accelerated progression of small adenomas and a lesion missing at colonoscopy. Longer follow-up is required to assess the efficacy of surveillance for EC.

Infliximab for treatment of steroid-refractory ulcerative colitis

BACKGROUND

Success achieved in two subtypes of Crohn's disease has persuaded a few investigators to experiment the monoclonal anti-tumour necrosis factor antibody infliximab in the treatment of ulcerative colitis. So far, however, the results (achieved in some 30 steroid-refractory patients included in two independent full-papers) indicate a rate of initial response of 50% and of remission of 25%.

AIMS

To analyse data of an open trial conducted on consecutive steroid-refractory severely ill patients admitted to our referral Unit.

PATIENTS AND METHODS

In 9 months, infliximab was given to 8 patients (4 male, 4 female aged 20-60 years) with uncontrolled ulcerative colitis of whom 6 were non-responders to parenteral steroids. All received the first infliximab dose as an intravenous infusion of 5 mg/kg.

RESULTS

Of the 8, 4 (50%) did not respond to the first injection and were submitted to urgent colectomy; the other four responded clinically. Two have maintained clinical remission for 7 months, without the need for steroids; both have received daily azathioprine at 2 mg/kg, and only one has received two further infliximab injections. Of the other two, one received a second injection at week 5, despite this relapsed, and underwent elective colectomy at that time; the other relapsed at 6 months and showed a partial response to a repeat infliximab infusion. Thus, the rate of sustained response is 2/8 (25%) in this study.

CONCLUSION

These results, achieved in an open uncontrolled fashion, seem to reflect those of other independent studies. In our opinion, these findings warrant an in-depth reappraisal of the indication to use infliximab as rescue treatment for refractory ulcerative colitis.

Two novel mutations and a new STK11/LKB1 gene isoform in Peutz-Jeghers patients

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominantly inherited disorder with variable expression and incomplete penetrance characterized by mucocutaneous pigmentation, predisposition to hamartomatous intestinal polyposis, and various other neoplasms. It occurs in approximately 1 in 8,300 to 29,000 live births. In nearly 50% of patients PJS is caused by germ line mutations in the STK11/LKB1 serine/threonine kinase gene, the only kinase gene currently known to act as a tumor suppressor. We have performed a mutation search in the STK11/LKB1 gene in 8 sporadic cases and 3 PJS families using a combination of different screening techniques. We have identified four mutations, two of which I177N and the IVS2+1A->G, were previously unreported. We have also evaluated the presence of cDNA alterations by means of RT-PCR analysis and direct cDNA sequencing and have found two aberrant transcripts in a single PJS case despite the lack of any apparent genomic alteration. Finally, we report the presence of a novel STK11/LKB1 cDNA isoform observed in all the normal subjects studied as well as in the majority of the PJS patients.

Cancer surveillance in ulcerative colitis: critical analysis of long-term prospective programme

BACKGROUND

Patients with longstanding ulcerative colitis are at increased risk of colorectal cancer. In the literature, no agreement has yet been reached regarding prevention strategies. Our report sums up a prospective study started in 1980.

METHODS

A total of 65 patients affected by ulcerative colitis for more than seven years were admitted to a regular colonoscopic and biopsy follow-up programme.

RESULTS

Some 20 years after the beginning of the study, 23 (35.3%) patients have been operated upon, 2 patients have died but not from cancer 29 (44.66%) patients have abandoned the programme. Only 11 (16.9%) patients have remained under colonoscopic surveillance.

CONCLUSION

These results cast some doubts on the significance of such a programme and on its long-term feasibility.

Small-bowel endoscopy

During the last year, promising results with the first clinical applications of capsule endoscopy have been reported; this is a new, revolutionary diagnostic method for endoscopic study of the small bowel. The method has chiefly been used in patients with obscure gastrointestinal bleeding, and in some cases has allowed additional diagnoses to be made in comparison with push enteroscopy, with a positive influence on patient management. New therapeutic possibilities have also been developed in push enteroscopy, emphasizing the role of this technique as an essential component of gastrointestinal endoscopy. Important innovations in enteroscopy technique have been described, aimed at increasing the depth of examination, and these will probably make it possible to extend endoscopic treatments to include the entire small bowel. Finally, numerous articles are still being published concerning intraoperative enteroscopy. It is to be hoped that, in future, the use of this invasive procedure will be based on data acquired by capsule endoscopy.

Idiopathic myenteric ganglionitis underlying intractable vomiting in a young adult

Inflammatory infiltration of intestinal myenteric plexuses (i.e. myenteric ganglionitis), along with severe intestinal motor abnormalities, may accompany paraneoplastic syndromes, neurological disorders and gastrointestinal infections, although rare cases can be idiopathic. In this report, we describe the case of a patient who presented with chronic intractable vomiting and weight loss associated with idiopathic myenteric ganglionitis mainly involving the stomach. Tissue analysis showed that the inflammatory infiltrate comprised T lymphocytes (CD4+ and CD8+), and peptide immunolabelling revealed a marked decrease of substance P/tachykinin immunoreactive staining in nerve fibres and myenteric neurones. Following systemic steroid therapy, the patient's symptoms dramatically improved, and after one year of follow-up his general condition remains satisfactory. The possible mechanisms leading to symptom generation and gastric dysmotility in the context of an idiopathic myenteric ganglionitis are discussed.

Small bowel polyps in Peutz-Jeghers syndrome: management by combined push enteroscopy and intraoperative enteroscopy

BACKGROUND

Polyps occur throughout the GI tract in Peutz-Jeghers syndrome; the major problem in the management of the syndrome lies in the small bowel.

METHODS

From January 1979 to January 1998, seven patients with Peutz-Jeghers syndrome underwent surveillance. Between 1979 and 1992 they were managed with upper and lower endoscopy every 2 to 3 years and surgery when intestinal obstruction occurred. From 1993 they also underwent enteroclysis and, on the basis of radiologic findings, push enteroscopy and/or intraoperative enteroscopy. Push enteroscopy was then performed every 2 years in all patients.

RESULTS

During the first period, 5 of 7 patients underwent emergency small bowel resection (2 operated twice). The patients were divided into 2 groups based on enteroclysis findings; the first comprised 4 patients with multiple polyps throughout the small bowel, and the second included 3 patients with polyps only in the proximal small bowel. Three of the 4 patients with diffuse polyposis underwent intraoperative enteroscopy during which on average 16 polyps per patient were removed (range 10 to 25 polyps; mean diameter 16 mm, range 3 to 50 mm). The remaining patient with diffuse polyposis had a single 25 mm polyp in the terminal ileum removed by retrograde ileoscopy; the more proximal polyps were removed by push enteroscopy. The patients with diffuse polyposis remained asymptomatic during follow-up (mean 50 months, range 47 to 57 months) and also underwent periodic push enteroscopy (mean 2.25 enteroscopies per patient, range 2 to 3) at which a mean of 8.5 polyps per patient (range 4 to 13 polyps) were removed (mean diameter 7.2 mm, range 3 to 15 mm). The 3 patients of the second group underwent periodic push enteroscopy alone (mean 3 per patient) during which a mean of 11.7 polyps per patient were removed (range 7 to 15 polyps: mean diameter 10.9 mm, range 3 to 40 mm). Enteroclysis was not repeated in these patients, who remained asymptomatic during follow-up (mean 47 months, range 46 to 48 months).

CONCLUSIONS

More effective clearance of small bowel polyps via enteroscopy will help reduce the need for emergency surgery with extensive intestinal resection in patients with Peutz-Jeghers syndrome.

Small-bowel endoscopy

During the last year, several interesting publications have further confirmed the role of enteroscopy in clinical practice. Of particular interest have been various articles concerning the use of two-way enteroscopy in large series of patients with obscure gastrointestinal bleeding or with radiological abnormalities. Reports continue to appear describing a high incidence of gastroduodenal or colonic lesions that were missed or misinterpreted during previous upper and lower endoscopies in patients with recurrent obscure bleeding. By contrast, there have been few outcome studies on patients with obscure bleeding, and the conclusions reached are not in full agreement. Other important publications have stressed the value of enteroscopy in selected cases of chronic unexplained diarrhea, for diagnosing small-bowel lesions caused by nonsteroidal anti-inflammatory drugs, and in identifying small-bowel tumors. In addition to numerous reports on intraoperative enteroscopy, the results of initial experience with laparoscopically assisted enteroscopy have also been reported.

Programmed cell death, proliferating cell nuclear antigen and p53 expression in mouse colon mucosa during diet-induced tumorigenesis

Western-style diets (WDs) trigger and sustain the early phases of tumorigenesis in mouse colon, and when continued throughout the life span lead to the development of dysplastic crypts. In order to evaluate the roles both of cell proliferation and programmed cell death (PCD) in WD-induced tumorigenesis, immunohistochemical detection of proliferating nuclear antigen (PCNA), in situ end labeling (TUNEL) of DNA breaks, and p53 protein were carried out in mouse colonic mucosa during prolonged feeding of two WDs. PCNA Labeling Index of colonic crypts was significantly higher in WD-treated animals than in controls only at the beginning of the nutritional study, the gap rapidly bridged by increased cell proliferation spontaneously occurring in the colonic mucosa during aging. A transient early homeostatic activation of PCD at the base of the crypt also was observed in WD groups. No changes in PCD were seen in the upper third of the crypt or in surface epithelium throughout the study, indicating that PCD in that colonic crypt segment produces a constant flux of cell loss, uninfluenced by homeostatic fluctuations. A major finding was an irreversible, progressive, age-related decline of PCD at the crypt base in both control and treated animals that occurred during the second half of the rodents' life span. p53 protein was not immunohistochemically detected, suggesting that neither overexpression of wild-type nor mutated forms of the protein are involved in the above mentioned changes.

Enteroscopic identification of an adenocarcinoma of the small bowel in a patient with previously unrecognized hereditary nonpolyposis colorectal cancer syndrome

Tumors of the small bowel are uncommon and seldom suspected on a clinical basis. Together with the relative inaccessibility of the small bowel to endoscopic investigation, the rarity of these tumors undoubtedly delays their diagnosis. The case reported is of a patient with an adenocarcinoma of the jejunum presenting as gastrointestinal bleeding of obscure origin. Diagnosis was by push enteroscopy, after several years of unsuccessful radiological and upper and lower endoscopic evaluation. The patient's family fulfilled the Amsterdam criteria for hereditary nonpolyposis colorectal cancer syndrome, which was previously unrecognized. This report emphasizes the value of push enteroscopy and the limits of radiography of the small bowel when investigating patients with obscure GI bleeding. It also underlines the importance of a careful evaluation of the pedigree (concerning history of colorectal and extracolonic cancer) of all patients, including those who present with adenocarcinoma of the small bowel; it is similarly important to consider the possibility of small bowel cancer in members of families with hereditary nonpolyposis colorectal cancer (HNPCC) syndrome.

Dysplastic changes in gastric fundic gland polyps of patients with familial adenomatous polyposis

BACKGROUND

Fundic gland polyps are the most common gastric lesion in patients with familial adenomatous polyposis and are traditionally considered a condition with no malignancy potential. However, some reports have recently questioned this view.

AIMS

To prospectively evaluate their prevalence and the associated dysplastic/malignant changes in a series of affected patients.

PATIENTS AND METHODS

Thirty-seven affected patients were carefully investigated by upper endoscopy over a three-year period. Multiple (at least 10) complete excisions of any representative polyp of the body-fundus were performed and a thorough pathological search for microscopic adenomatous/dysplastic changes carried out.

RESULTS

Of 37 patients, 19 (51.3%) showed gastric fundic gland polyposis and 18 of them gave consent for polypectomies. Overall, 425 endoscopic polypectomies were performed, with a mean of 23.6 +/- 14.6 per patient. At pathology, all excised polyps of the body-fundus were found to be fundic glandular. Microscopic adenomatous changes within such polyps were identified in 8 (44.4%) patients. All the adenomatous foci revealed mild dysplasia with no case of severe atypia or carcinoma. Patients with microadenomas showed a significantly higher total number of gastric polyps compared with those without microadenomas (p < 0.03). No other differences between the two groups were observed. Two further patients presented microadenomas in apparently normal antral mucosa and one also showed a 6 mm antral adenoma with mild dysplasia. Finally, the search for Helicobacter pylori was always negative.

CONCLUSIONS

Patients with familial adenomatous polyposis and gastric fundic gland polyps have a high prevalence of microscopic adenomatous foci within such lesions; nevertheless, these foci seem not to be associated with signs of severe atypia or carcinoma. Moreover, microadenomas are ubiquitous throughout the stomach, as well as in the rest of the gut, and their natural history is still undefined. Thus, their malignancy potential remains uncertain. More extensive follow-up is warranted to better investigate the long-term biological behaviour of these lesions but, at present, our data do not support the need for a change in the usual intervals of upper endoscopy surveillance in familial polyposis patients with or without gastric fundic glands polyps.

Small bowel tumors and polyposis syndromes

Tumors of the small bowel are uncommon and seldom suspected on a clinical basis. Together with the relative inaccessibility of the small bowel to endoscopic investigation, the rarity of these tumors undoubtedly delays the diagnosis. Small bowel tumors may be an interesting field of application for enteroscopy, which now can be readily performed with dedicated enteroscopic evaluation in patients with suspected small bowel neoplasia could improve prognosis and treatment. Enteroscopy may also play an important role in the surveillance of inherited polyposis syndromes, as in other precancerous condition of the small bowel. In Peutz-Jeghers syndrome it may reduce polyp-induced complications and improve planning for surgery; in familial adenomatous polyposis it may contribute to preventing upper gastrointestinal tract cancer.

K-ras2 activation and genome instability increase proliferation and size of FAP adenomas

The possible role of K-ras2 mutations and aneuploidy toward increase of proliferation and adenoma size in Familial Adenomatous Polyposis (FAP) adenomas is not known. The present study addresses these issues by investigating 147 colorectal adenomas obtained from four FAP patients. The majority of adenomas had size lower than or equal to 10 mm (86%), low grade dysplasia (63%), and were preferentially located in the right colon (60%). Normal mucosa samples were obtained from 19 healthy donors. Three synchronous adenocarcinomas were also investigated. K-ras2 mutation spectrum was analysed by PCR and Sequence Specific Oligonucleotide (SSO) hybridization, while flow cytometry (FCM) was used for evaluating degree of DNA ploidy and S-phase fraction. Overall, incidences of K-ras2 mutations, DNA aneuploidy and high S-phase values (>7.2%) were 6.6%, 5.4% and 10.5%, respectively. In particular, among the adenomas with size lower than 5 mm, K-ras2 mutation and DNA aneuploidy frequencies were only slightly above 1%. Statistically significant correlations were found between K-ras2 and size, DNA ploidy and size and K-ras2 and S-phase (p < 0.001). In particular, among the wild type K-ras2 adenomas, high S-phase values were detected in 8% of the cases versus 57% among the K-ras2 mutated adenomas (p = 0.0005). The present series of FAP adenomas indicates that K-ras2 activation and gross genomic changes play a role toward a proliferative gain and tumour growth in size.

STK11 mutations in Peutz-Jeghers syndrome and sporadic colon cancer

A potential tumor suppressor gene, STK11 , encoding a serine threonine kinase, has recently been identified on chromosome 19p13. Germ-line mutations of this gene have been found in patients with Peutz-Jeghers syndrome (PJS). To further investigate the relevance of STK11 mutations in PJS, we analyzed its coding sequence in nine patients and identified two deletions and three missense mutations. Because intestinal carcinomas have been observed to develop in association with PJS, we analyzed tumors from 71 patients for allelic deletions (loss of heterozygosity) and STK11 gene mutations, to elucidate the etiological role of STK11 gene in sporadic colorectal cancer. Loss of heterozygosity, evaluated using the microsatellite D19S886, was observed in 10 of 52 informative cases. No somatic mutations were detected except for a missense alteration in one tumor. Our data indicate the heterogeneity of PJS and the infrequent involvement of the STK11 gene in colorectal cancer.

Specific K-ras2 mutations in human sporadic colorectal adenomas are associated with DNA near-diploid aneuploidy and inhibition of proliferation

Recent studies indicate that p21ras proteins mediate their multiple cell functions through interactions with multiple effectors and that the number of new effectors is growing. We recently reported that K-ras2 mutations in human colorectal adenomas were associated with chromosome instability and proliferation changes. In the present study, we extend these previous observations. Hereditary and multiple (n > or = 5) adenomas and adenomas with early cancer were excluded. Dysplasia was moderate in 91 cases and high in 25, and the median adenoma size was 1.5 cm. K-ras2 spectrum analysis was done by sequence-specific oligonucleotide hybridization using nuclear suspensions provided by analysis and sorting of multiparameter flow cytometry. In particular, tissue inflammatory cells were separated for DNA diploid tumors, whereas DNA aneuploid epithelial subclones were analyzed separately. K-ras2 mutations and DNA aneuploidy were both detected in 29 of 116 (25%) cases. DNA aneuploid index was in the near-diploid region in the majority of cases. DNA aneuploidy was strongly associated with G-->C/T transversions. An association was also found between low S-phase values and G-->A transitions. These findings were confirmed using multivariate logistic regression analysis to account for the effects of size, dysplasia, site, type, age, and sex. These data suggest that specific K-ras2 mutations in a subgroup of human sporadic colorectal adenomas play a role in chromosome instability and, contrary to expectations, are associated with inhibition of proliferation.

Main issues in push enteroscopy

Endoscopic evaluation of the small bowel has rapidly evolved over the last ten years, marking an important milestone in the diagnosis and treatment of small bowel diseases. Gradual progress in endoscopic techniques and development of new instruments with full therapeutic options have aided and spread the use of enteroscopy. However, some basic issues concerning its appropriate use in clinical practice remain to be solved. This article stresses the importance of lesions missed at oesophagogastroduodenoscopy in patients with obscure gastrointestinal bleeding who undergo push enteroscopy, focuses on the limits of outcome studies related to therapeutic enteroscopy, and critically reviews the clinically relevant indications to push enteroscopy.

Correlation between 1p deletions and aneusomy in human colorectal adenomas

Human sporadic colorectal adenomas are characterized by a relatively high occurrence of aneuploidy. Similarly, 1p deletions have been reported to be an early event in colorectal tumorigenesis, while chromosome 7, 17 and 18 gain/losses were also found. The present study investigated 1p deletions, the numerical aberrations of chromosomes 1, 7, 17 and 18, and the nuclear DNA content as obtained by flow cytometry in a series of 34 human sporadic colorectal adenomas. From these adenomas, 51 intra-adenoma regions were microdissected according to 2 degrees of dysplasia and presence of foci of early cancer. Isolated epithelial nuclei were analyzed by fluorescence in situ hybridization interphase cytogenetics using centromeric probes for chromosomes 7, 17 and 18 and, in a double-target analysis, a centromeric probe for chromosome 1 simultaneously with a telomeric probe mapping to the 1p36 band. Aneuploidy incidence due to presence of numerical aberrations for at least one among the investigated chromosomes and/or abnormal flow-cytometric DNA content was 35%, while 1p deletion incidence was 38%. The correlation of 1p deletions with aneuploidy was statistically highly significant (p = 0.003), suggesting that loss of genes in this region may be implicated in chromosome instability.

Extended lymph node dissection for gastric cancer: results of a prospective, multi-centre analysis of morbidity and mortality in 118 consecutive cases

This study reports interim data on post-operative morbidity, hospital mortality and duration of hospital stay of Italian patients undergoing extended lymph-node dissection combined with a pancreas-preserving technique for gastric cancer. Of the 218 patients admitted to one of eight general and/or university hospitals in North Italy, 118 were enrolled in the trial. Eligible patients presented with proven primary adenocarcinoma of the stomach without clinical evidence of distant, peritoneal and/or liver metastasis, or metastasis in para-aortic and retropancreatic nodes at intraoperative biopsy. Patients underwent the extended procedure as described by the Japanese Research Society for the Study of Gastric Cancer, following the Maruyama pancreas-preserving technique. A strict quality control system was used to ensure the performance of a standard surgical treatment. A surgeon of the reference centre (M.D.), who stayed at the National Cancer Center Hospital in Tokyo to learn the D2 technique from a specialist Japanese surgeon, became the trial supervisor and assisted each surgeon in all the Italian participating centres. The patients were staged according both to the TNM system and to the General Rules for the Gastric Cancer Study in Surgery and Pathology. Post-operative surgical complications developed in 21 patients (17.8%). The non-surgical complication rate was 2.5%. Reoperation was necessary in six patients (5%), all of whom survived. The 30-day mortality rate for the eligible group was 2.5%. The overall hospital mortality was the same. Total gastrectomy was associated with a slightly higher operative mortality (4.5% vs 1.3%). Only one patient died from an anastomotic leak. The rate of leakages was higher after total than after distal gastrectomy (15.9 vs 5.4%); the association of splenectomy and pancreatectomy worsened the morbidity rate. D2 lymphadenectomy with pancreas-preserving technique, when performed at experienced centres, seems a feasible and safe technique for the radical treatment of gastric cancer in selected Western patients.

Microsatellite instability is associated with the histological features of the tumor in nonfamilial colorectal cancer

Replication errors (RERs) at microsatellite loci were examined in 46 specimens of nonfamilial colorectal cancer. Somatic microsatellite alterations in at least two genetic loci, D11S904, D13S175, D2S123, and D10S197, consistent with a RER(+) phenotype were found in four cases (8.7%). Six additional cases (13%) showed alterations at a single locus. Mucinous differentiation was observed in 3 of 4 (75%) adenocarcinomas with a RER(+) phenotype and only in 19% (8 of 42) of RER(-) adenocarcinomas (P < 0.05). A distinct cap of inflammatory cells at the advancing edge of the tumor and Crohn's-like reaction in peritumoral stroma were histologically identified in 50 and 25% of RER(+) and in 5 and 0% of RER(-) tumors, respectively (P < 0.05). Also, the plexiform pattern of growth of carcinoma turned out to be significantly associated with the RER(+) phenotype (P < 0.05). Mucinous differentiation and stromal inflammatory reactions are frequent features of hereditary nonpolyposis colorectal cancer in which germ-line mutations of mismatch repair genes cause genetic instability. Our results indicate that a link exists between such histological features and somatic genetic instability consistent with a RER(+) phenotype also in nonfamilial colorectal cancer.

High prevalence of adenomas and microadenomas of the duodenal papilla and periampullary region in patients with familial adenomatous polyposis

BACKGROUND

Patients with familial adenomatous polyposis (FAP) are traditionally considered to be at high risk for duodenal-papillary and periampullary adenomas and cancer.

AIM

To evaluate prospectively the prevalence, histology and clinical significance of ampullary and periampullary macroscopic and microscopic lesions in our population of affected patients.

SETTING

Three gastroenterological departments of northern Italian hospitals.

PATIENT AND METHODS

Twenty-five affected patients were carefully investigated over a 24-month period by end-viewing and side-viewing upper panendoscopy. Biopsies were performed on representative macroscopic lesions and randomly on normal-appearing papillary and periampullary mucosa.

RESULTS

Seven patients had macroscopic adenomas of the duodenal papilla, three of the periampullary region and five at both sites (cumulative prevalence 40%). An additional six patients had macroadenomas in the rest of the duodenum (overall prevalence 64%). Microscopic adenomas were identified in nine and two patients in the papilla and periampullary region, respectively, and in three at both sites (overall prevalence 44%). Thus, a total of 17 (68%) patients presented macro- or microadenomas at these locations. The prevalence rose to 72%, when a further patient with macroadenomas in the rest of the duodenum only was included. Malignancy was not encountered and severe dysplasia was observed only in a macroadenoma of the second duodenal portion. A higher frequency of macroadenomas in the papilla and periampullary region was significantly correlated with the presence and number of such lesions in the rest of the duodenum (P = 0.04). No other significant association was detected either between micro- or macroadenomas at different sites or with the demographic, clinical and pathological features.

CONCLUSION

This study confirms that the duodenal papilla and periampullary region are sites with high prevalence of macro- and microscopic adenomas in patients with FAP. However, our data do not seem to support a higher frequency and malignancy potential of such lesions as compared to polyps in the rest of the duodenum. Nevertheless, these findings warrant a periodic, careful examination of the duodenum with either end-viewing or side-viewing endoscopy, the need for random biopsies of the papilla and periampullary region and the removal of any larger or rapidly growing lesions detected.

Apoptosis, cell replication, and Western-style diet-induced tumorigenesis in mouse colon

In this study, feeding Western-style diets (WDs) to mice for a duration of two years without any chemical carcinogen led to the development of gross colonic lesions that were histologically classified as dysplastic crypts and focal hyperplasias with or without atypical nuclei. To better understand early biological events contributing to the development of colonic neoplasia, grossly normal colonic mucosa was investigated; mitotic and apoptotic colonic epithelial cells, atypical mitosis, and atypical nuclei were studied. A significant and transient increase of mitotic activity in the basal and intermediate portions of the colonic crypts was seen in young mice after feeding them the WDs. This was accompanied by diffuse activation of apoptosis of the colonic epithelial cells. In the middle of the rodents' life span, after administration of both the WDs and control diet, the rodents developed a marked depletion of apoptotic epithelial cells in the mid-region of the colonic crypts; this was followed by the expansion of an epithelial cell population containing atypical nuclei, and the emergence of the gross lesions noted above. With this sequence of events, prolonged feeding of WDs to mice produced single-crypt dysplastic lesions and focal hyperplasias indicative of tumorigenesis.

Deletions at chromosome 1p by fluorescence in situ hybridization are an early event in human colorectal tumorigenesis

BACKGROUND & AIMS

Deletions at chromosome 1p have been observed frequently in human colorectal adenocarcinomas, suggesting that loss of genes in this chromosome arm is relevant for tumorigenesis. The aim of this study was to investigate whether 1p deletions are already present in adenomas within selected foci of dysplasia and early cancer using two-color fluorescence in situ hybridization.

METHODS

Fifty-one sectors characterized by low- and high-grade dysplasia and early cancer were microdissected from 34 adenomas, and isolated epithelial nuclei were subjected to hybridization with probes to the telomeric and centromeric regions of chromosome 1.

RESULTS

Deletions of 1p were detected in 13 of 34 adenomas (38%). In particular, low/moderate and high dysplasia and foci of early cancer had 1p deletion frequencies of 31%, 44%, and 50%, respectively.

CONCLUSIONS

Compared with classic cytogenetics, fluorescence in situ hybridization seems to be a particularly useful methodology to detect 1p deletions in human colorectal adenomas. The present findings indicate that loss of genes from the 1p chromosome arm may play an important role during the early steps of the colorectal carcinogenesis.

Screening for colorectal cancer by once only sigmoidoscopy: a feasibility study in Turin, Italy

OBJECTIVES

To assess the impact on compliance of three invitation methods, as well as the acceptability and efficacy of two bowel preparation regimens, for endoscopic screening in the general population.

METHODS

1170 subjects (men and women aged 55 to 59, in the rosters of a sample of general practitioners (GPs) in Turin), were randomly allocated to one of three invitation groups (A: personal letter, signed by GP, with a pre-fixed appointment; B: same as for A + letter supporting the study by a well known scientist; C: letter signed by the study coordinator, NS) and two preparation regimens (i: one enema, self administered at home two hours before the test; ii: two enemas, administered the night before and two hours before the test). A postal reminder was mailed to non-attenders. A sample of non-responders was contacted for a telephone interview by a trained nurse. Written consent was obtained from all subjects undergoing the test.

RESULTS

A total of 278 subjects attended for sigmoidoscopic screening. An invitation from the GP alone produced the highest response rate (compliance: A = 29.3%; B = 24.9%; C = 26.8%). A single enema was as effective as two enemas in achieving satisfactory preparation for the test: the proportion of subjects invited to repeat the test was 8.1% in the single enema group, and 9.6% in the group receiving two enemas.

CONCLUSIONS

Compliance with this screening procedure tends to be low. One enema, self administered two hours before sigmoidoscopy, can ensure a satisfactory bowel preparation.

Clinical enteroscopy

We prospectively evaluated the diagnostic yield of push enteroscopy using either the Olympus SIF 10-LY fiberscope or the SIF-100 video enteroscope in 120 patients suspected of having small-bowel pathology. Insertion beyond the ligament of Treitz, checked by fluoroscopy, ranged from 30 to 150 cm (median 100). The source of bleeding was identified in 25 (41%) of 61 patients referred for gastrointestinal bleeding of obscure origin; vascular malformations were the most common finding, followed by neoplasias. Of 16 patients with inherited polyposis syndromes, multiple distal duodenal or jejunal hamartomas were diagnosed in five of six with Peutz-Jeghers syndrome and multiple duodenal or jejunal adenomas in six of 10 with familial adenomatous polyposis. Overall, isolated vascular malformations were successfully cauterized in three patients, and polypectomy was performed in 12 patients. Endoscopic and histological alterations, in both duodenum and jejunum, were found in 16 of 43 patients with diarrhea and/or malabsorption of unclear origin. The remaining 27 had normal duodenal and jejunal mucosal appearances; six had abnormal histological findings only in the jejunum and one both in the duodenum and in the jejunum. If we take jejunal histology as diagnostic, the sensitivity of duodenal histology was 74% and the specificity was 100%. We conclude that push enteroscopy provides useful diagnostic information and has therapeutic capabilities in patients with small-bowel pathology.

Treatment and follow-up of large bowel adenoma

The current clinical interest in large bowel adenoma is due to the evidence that most carcinomas arise in benign adenomas and therefore endoscopic removal of adenomas interrupts the sequence that leads to cancer. Colonoscopy is the best method for the detection and treatment of adenomas, with a diagnostic accuracy of 94% and a low incidence of complications. The majority of polyps can be resected by snare polypectomy. Regarding small polyps, snare polypectomy without current application is recommendable and hot biopsy should be avoided owing to a non negligible risk of hemorrage. Though clinical significance of small polyps is controversial, in our experience and in other studies they have a potential for malignant progression (2.4% of adenomas containing invasive carcinoma are 6 mm or less in diameter) and those located in the rectosigmoid are predictive of proximal neoplasms. If endoscopic polypectomy significantly reduces the incidence of colorectal cancer, patients submitted to adenoma removal have an increased risk for metachronous adenomas. Surveillance is therefore mandatory, once the presence of synchronous adenomas has been ruled out (clean colon). Risk factors for adenoma recurrence are family history, age, size of adenoma, multiple adenomas, dysplasia, villous histotype. Holding in due consideration compliance, risk of complications, logistic problems and costs, the following guide-lines can be proposed: total colonoscopy at the time of endoscopic polypectomy (to obtain a "clean colon") and, in the case of unsatisfactory examination, within one year. first check at 3 years and, if negative, subsequent check at 5 years. for small tubular adenomas surveillance is indicated only in the case they are multiple. The evaluation of some intermediate bio-markers might contribute to the predictive determination of adenoma recurrence, with the goal to select groups of patients with the highest risk of recurrence of adenomas.

Colorectal cancer in patients with ulcerative colitis. A prospective cohort study in Italy

BACKGROUND

The aim of this study was to assess the development of dysplasia or cancer in patients with ulcerative colitis and to determine the effectiveness of colonoscopy and biopsy follow-up in colon cancer surveillance.

METHODS

From 1980 to 1986, 65 patients who had ulcerative colitis for 7 years or more participated in a surveillance program of colonoscopy and biopsy. This cohort was followed until December 1992. Forty-nine patients (75.4%) had extensive colitis and 16 (24.6%) left-sided colitis. The mean disease duration was 17.2 years. Three hundred four colonoscopies were performed. During each endoscopy, random biopsies were performed.

RESULTS

Seven patients had definite dysplasia of the colorectal mucosa. Four of them had high grade lesions and underwent surgery. In all of these patients, colon cancer (3 Dukes' Stage A, 1 Dukes' Stage B) was found. No cancer was found in the other patients. Pedunculated adenomas were excised from 6 other patients during colonoscopy. When dysplasia was diagnosed, these patients were older than those who were dysplasia free, whereas the age at onset of colitis was significantly higher in the former (P < 0.01). Fifteen patients discontinued follow-up. Two of them developed colon cancer diagnosed at an advanced stage.

CONCLUSIONS

Dysplasia, especially of high grade, is a marker of colon cancer risk in patients with longstanding ulcerative colitis. Intensive colonoscopy and biopsy surveillance can lead to the diagnosis of colon cancer at a potentially curable stage. In this series, older age appeared to be an additional risk factor. A careful selection of patients with ulcerative colitis seems mandatory to minimize the cost and optimize the benefit of colon cancer surveillance programs.

Mucosal cell proliferation in patients with hyperplastic colorectal polyps

BACKGROUND

Morphologic, histochemical, and cytoproliferative characteristics differentiate hyperplastic polyps from adenomas. Even so, these polyps are indicators of populations with a high colorectal cancer risk. Since changes in mucosal cell proliferation are highly predictive biomarkers of the adenomacarcinoma sequence, this study examined the cytoproliferative profiles of mucosa bearing hyperplastic polyps, in a search for the significance of such lesions in bowel carcinogenesis.

METHODS

Proliferative activity demonstrated by immunohistochemical detection of the in vitro uptake of bromodeoxyuridine was evaluated in the rectal mucosa of 26 patients with hyperplastic polyps, 35 with adenomas < 1 cm, 60 with adenomas > 1 cm, 10 with adenomas + synchronous hyperplastic polyps, and 400 controls.

RESULTS

An upward shift of the major DNA synthesis zone to the intermediate and surface crypt compartments was found in all four patients groups. Significant hyperproliferation, on the other hand, was only observed in patients with large adenomas or hyperplastic polyps, or small adenomas and synchronous hyperplastic polyps.

CONCLUSIONS

These findings suggest that hyperplastic polyps are morphologic indicators of tumor initiation in the rectal mucosa and its ensuing hyperproliferation. Abnormalities in the distribution of proliferation in the mucosa do not appear to be specifically associated with the morphogenesis of hyperplastics polyps.

Rectosigmoid polyps as markers of proximal colonic neoplasms: a cost benefit analysis of different diagnostic protocols

The predictive value of hyperplastic polyps of the rectosigmoid for neoplastic lesions in the proximal colon is controversial. Some authors who deny predictive value have proposed a protocol which entails initially biopsying rectosigmoid polyps, and only in the case of adenomas then proceeding to total colonoscopy (protocol 1). The diagnostic and economic efficiency of this protocol, and of an alternative which entailed the full exploration of the colon during the initial examination in the case of rectosigmoid polyps (protocol 2), were evaluated by retrospectively simulating their application to 216 patients who had undergone total colonoscopy. A proximal neoplastic pathology was present in 49.5% of patients with rectosigmoid adenoma, 27.3% of patients with distal non neoplastic polyps alone (33.3% if only distal hyperplastic polyps were considered) and 11% of patients with no distal polyps. Protocol 1 gave rise to a higher cost ($ 58,413), not only compared to protocol 2 ($ 50,276), but also compared to total colonoscopy in all patients ($ 57,008); there was also a larger number of patients who eluded diagnosis (29%, against 16% in protocol 2). In terms of cost per lesion detected and of colorectal cancers prevented (on the basis of an evolution to cancer of 5% of adenomas), total colonoscopy for all patients on principle is advantageous compared to either protocol ($ 864 per proximal lesion and $ 7,082 per cancer prevented). Since distal hyperplastic polyps are also predictive of proximal neoplastic pathology, when rectosigmoid polyps are detected it is both indicated and economic to proceed with the exploration of the entire colon during the initial examination. This appears to be a reasonable compromise compared to total colonoscopy on principle, which has higher overall costs. The latter management, however, should not be ruled out, since it has a better diagnostic yield and lower cost per lesion detected and per cancer prevented.

Clinical evaluation of push-type enteroscopy

BACKGROUND AND STUDY AIMS

Endoscopic exploration of the small bowel is potentially of prime importance in studying gastrointestinal bleeding of obscure origin, diarrhea and malabsorption, neoplasia, and other clinical conditions, but the method is still problematic because of the limited efficacy of sonde-type enteroscopes. This study evaluates the diagnostic yield of two push-type enteroscopes fitted with tip deflection and a biopsy channel.

PATIENTS AND METHODS

Seventy-two consecutive patients underwent enteroscopy using either an Olympus SIF-10 LY fiberscope or an Olympus SIF-100 video enteroscope. The depth of insertion was always checked by fluoroscopy, and ranged 30-120 cm beyond the ligament of Treitz.

RESULTS

Angiodysplasia was identified as the source in eight of 20 patients referred for gastrointestinal bleeding of obscure origin, and electrocoagulation was successfully performed in one case. A jejunal polyp was the cause of obscure bleeding in one patient. Radiological evidence of neoplasia/lymphoma located in the third portion of the duodenum or in the upper jejunum was ruled out in 10 of 12 patients. A normal jejunal appearance was found in two patients with lymphoma, subsequently confirmed by a normal enteroclysis. Duodenal or jejunal polyps were removed in seven of nine patients with familial polyposis. Endoscopic and histological alterations were found in nine of 24 patients with diarrhea or malabsorption. In addition, jejunal histology supplied the diagnosis in five patients with a normal endoscopic mucosal appearance. Only 18% of patients described slight, transient pain, and there were no complications. The tolerance and diagnostic efficacy were the same with both instruments.

CONCLUSIONS

Even though push-type enteroscope exploration is restricted to the jejunum, the instruments are safe and efficacious in clinical practice, and permit indepth study of small bowel anatomy and pathology.

Emergency endoscopy: recanalization of intestinal obstruction caused by colorectal cancer

Endoscopic recanalization was attempted in 17 patients with obstruction caused by colorectal cancer who were at high surgical risk on account of their poor clinical condition. Combined use was made of pneumatic and mechanical dilation, debulking with a diathermal snare, and photoablation with neodymium-yttrium-aluminum-garnet laser. Successful recanalization was obtained in 94% of cases. The only failure was in a patient with a neoplasm of the rectosigmoid junction. Elective surgery was not performed on the patients after recanalization because of the presence of severe concomitant disease or diffuse metastasis. Patients were followed for 6.25 +/- 6.17 months with 1.6 +/- 0.7 treatments within the first month to stabilize patency and then with an average of 0.88 +/- 0.63 treatments per month to maintain patency. Only 2 patients had recurrence of obstruction, and the actuarial survival was 63% at 6 months and 23% at 1 year. Endoscopic treatment has proved effective because it allows rapid recanalization with resolution of emergency and maintenance of patency in patients for whom elective surgery is not indicated. In selected cases, therefore, endoscopic recanalization is a sound alternative to emergency surgery.

Small rectosigmoid polyps as markers of proximal neoplasms

PURPOSE

The aim of this study was to determine the spatial distribution and histotype of small colorectal polyps and to determine the validity of distal-small colorectal polyps as markers of proximal neoplasms.

METHODS

In 366 patients who underwent total colonoscopy and removal of all polyps, the presence and features of polyps were recorded. The relationship between proximal neoplasms and distal polyps was investigated in 216 of 366 subjects who had no personal or familial history of colorectal neoplasia.

RESULTS

Of 366 patients, 96 were free from polyps. A total of 733 small colorectal neoplasms was removed from the remainder: 79.9 percent neoplastic and 20.1 percent hyperplastic, inflammatory, or hamartomatous. High-grade dysplasia was noted in 2.7 percent of the neoplastic polyps. One adenoma containing invasive carcinoma was observed. In the subset of 216 patients, proximal neoplasms were found in 11.4 percent of those with no distal polyps, 33.8 percent of those with distal-small colorectal polyps only (P < 0.01), and 58.8 percent of those with at least one polyp > 5 mm in diameter (P = 0.001). The proximal neoplasm percentage was the same in patients with at least one adenomatous-small polyp and those with only hyperplastic-small polyps.

CONCLUSIONS

A distal-small colorectal polyp, whether adenomatous or hyperplastic, may be a proximal neoplasm marker. Total colonoscopy is thus justified in all patients with distal polyps, regardless of their size and histotype.

Octreotide in the treatment of bleeding due to angiodysplasia of the small intestine

Three patients with a history of bleeding due to small bowel angiodysplasia (repeated melena or occult fecal blood with serious anemia) were treated for 10-40 months with octreotide, a somatostatin analog that reduces the splanchnic flow. A dose of 0.1 mg subcutaneously twice a day was followed by an increase in hemoglobin, and reduction or elimination of the need for transfusions. There were no further melena episodes, and stool hemoglobin became stably negative in two cases. Suspension of the drug after 6 months in one case was followed by renewed bleeding, and resumption led to a further response. Lower doses tried in another case were ineffective. Although these uncontrolled clinical cases do not prove its efficacy, octreotide appears to be beneficial in the control and prevention of bleeding due to diffuse small bowel angiodysplasia. There is no evidence that it results in regression of angiodysplasias, as they persisted in the patient subjected to control jejunoileoscopy.

Bromodeoxyuridine uptake and proliferating cell nuclear antigen expression throughout the colorectal tumor sequence

In vitro uptake of bromodeoxyuridine and expression of proliferating cell nuclear antigen (PCNA) were evaluated histochemically in rectal mucosa of control subjects and subjects with colorectal neoplasia in large intestine adenomas and adenocarcinomas. Both labeling indices progressively increased along the path of tumor progression, as did the difference between them (PCNA labeling indices were always greater than those of bromodeoxyuridine). The correlation between them was fairly close in the controls and in adenomas with low-grade dysplasia, whereas no significant linear relations were noted in adenomas with high-grade dysplasia or in adenocarcinomas. The progressive increase in PCNA would thus seem to be related to both hyperproliferation and neoplastic deregulation of PCNA synthesis. In the mucosa of subjects with colorectal neoplasia, PCNA labeling revealed hyperproliferation but not the surface-wards shift of the proliferative compartment detected by bromodeoxyuridine. PCNA expression, therefore, is not a sufficiently sensitive marker of the risk of tumor transformation in the intestinal mucosa.

Cell proliferation in colorectal adenomas containing invasive carcinoma

Immunohistochemical detection of the nuclear antigen recognised by the monoclonal antibody Ki67, DNA polymerase alpha, and the proliferating cell nuclear antigen (PCNA), and histochemical staining for the argyrophilic proteins associated with the nucleolar organizer regions (AgNOR) were carried out on histological sections from 107 colorectal adenomas containing invasive carcinoma (ACIC), including 7 with regional lymph node metastases. Separate evaluations were made for fields corresponding to adenoma with low-grade dysplasia, adenoma with high-grade dysplasia and early cancer. The same techniques were also employed in 20 cases of normal mucosa and 20 advanced carcinomas. The mean percentages of Ki67, DNA polymerase alpha, and PCNA-positive nuclei and the number of AgNOR per nucleus progressively increased along the sequence from normal mucosa via low-grade and high-grade dysplasia adenoma to advanced cancer, whereas the early cancer values were not significantly different from those in the low-grade dysplasia areas. No significant difference in PCNA positivity and number of AgNOR were noted in ACIC with and without lymph node metastases. It is suggested that the decrease in proliferative activity thus revealed in early cancer may be due to changes in the submucosa microenvironment caused by invasion, and that the metastatic potential of an early colorectal cancer cannot be correlated to such activity.

Correlations between rectal mucosa cell proliferation and the clinical and pathological features of nonfamilial neoplasia of the large intestine

An in vitro study of proliferative activity as shown by immunohistochemical detection of the uptake of bromodeoxyuridine was run on rectal biopsies from 400 patients with nonfamilial large bowel neoplasia: 200 adenoma; 150 adenocarcinoma; 50 adenoma plus adenocarcinoma. The controls were 400 subjects with negative personal and family histories of colorectal neoplasia. The number and height distribution of bromodeoxyuridine positive cells were determined by dividing the crypt into five longitudinal compartments. The total labeling index and the labeling index of each compartment were higher in all three groups compared with the controls. In subjects with adenoma, total labeling index and labeling index values were correlated with tumor size and decreased in function of the duration of the polyp-free colon state. The major zone of DNA synthesis had shifted to the intermediate and surface crypt compartments in all three groups. This stage II abnormality was more marked in adenoma patients with a high degree of dysplasia and in those with adenoma plus adenocarcinoma. Hyperproliferation and the proliferative compartment shift are cytokinetic abnormalities that coexist in the flat rectal mucosa of patients with colorectal neoplasia. Nonetheless, they are independent, controlled by different factors, and are expressions of different biological aspects of large bowel carcinogenesis.

Needle biopsy of submucosal lesions of the gastrointestinal tract

Needle biopsy of submucosal lesions is an important addition to the diagnostic capabilities of gastrointestinal endoscopy. A series of 22 cases is described employing a guillotine needle to diagnose submucosal lesions, 4 of which were infiltrating adjacent carcinomas. The specimens obtained were sufficient for firm histological diagnosis in 20 cases. There were no complications apart from minor bleeding in 1 case.

Late cytokinetic abnormalities in irradiated rectal mucosa

Late cytokinetic changes of the colonic crypt epithelium after radiation therapy were investigated. A monoclonal antibody to bromodeoxyuridine (anti-BrdU MAb) was used in tissue specimens previously incubated with BrdU to show S-phase cells by immunohistochemical technique. Endoscopic rectal biopsies were taken from 30 patients previously treated with radiotherapy for gynaecological cancer and from 50 patients with comparable but untreated neoplasms, as controls. Number and height distribution of S-phase cells were evaluated by dividing each crypt column into 5 equal longitudinal compartments. No statistically significant differences were found in total Labelling Index (LI) between controls and irradiated mucosa, whereas LI per crypt compartment, percentage of labelled compartments and percentage of BrdU-positive cells in the middle and superficial portions of the crypt were significantly higher in patients submitted to radiation therapy. This kinetic abnormality corresponds to a progressive shift of the major zone of DNA synthesis to the upper third of the crypt as a late reaction to radiation and represents an early step in the histogenesis of colorectal cancer. These results lend support to the view that there is a higher risk of colorectal carcinoma after pelvic irradiation.

[Lipoma of the small intestine. A clinical case]

The paper reports a case of a 45-year-old female with long-standing anemia, recurrent abdominal pain and subocclusive crises. Following a negative endoscopy of the upper tract of the large intestine, barium enema and angiography, the patient underwent total colonoscopy. Massive bleeding from the ileal valve suggested an ileal pathology: a small intestine enema confirmed a polypoid proliferation 60 cm above the Bahuino valve with related ileal invagination 25 cm long. The patient underwent surgery and pathological findings revealed a 7 cm-wide ileal lipoma near a small angiodysplasia. The latter seemed to be the cause of bleeding. The diagnosis of small intestine tumours is made difficult by the fact that the only important signs are abdominal pain, intestinal bleeding and subocclusive crises, which are common symptoms in many pathologies. The authors stress the importance of a thorough endoscopic examination and selective angiography.

Colorectal adenomas containing invasive carcinoma. Pathologic assessment of lymph node metastatic potential

Adenomas that contain early invasive carcinoma (ACIC) represent the earliest form of clinically relevant cancer of the colorectum in most patients. In order to assess the incidence of nodal metastases of ACIC, we studied 31 patients in whom the colon was resected after endoscopic polypectomy (EP) done from 1975 to 1987. We also reviewed the pathologic features reported in individual cases and in literature series of ACIC with lymph node metastases published from 1958 to 1986. The lymph node metastatic potential of ACIC is relatively high, ranging from an average value of 8.5% in the literature of to 16.1% in our own study, and is equivalent to the range of 10%-17% that occurs in colorectal carcinomas that invade the submucosa. When an ACIC is seen in an EP specimen in which the polypectomy margin is normal, the decision as to whether the patient should enter a follow-up protocol or have radical surgical resection is determined by the assessment of the probability of the occurrence of nodal metastases. According to several authors, certain histopathologic features make it possible to distinguish between an ACIC with a high-risk of nodal metastases versus those with a low-risk. The most relevant pathologic parameters include the state of the resection margins, the grade of the invasive carcinoma, and the presence or absence of vascular invasion. Of 351 cases of ACIC that were operated on, derived from 16 literature series, 45.6% were high-risk cases and 8.5% had lymph node metastases. In our group of high-risk ACIC that had surgical resection subsequently, the lymph node metastatic rate was 35.7%. Our results help to estimate the nodal metastatic potential of early colorectal carcinomas and stress the importance of adequate pathologic evaluation in order to assess metastatic risk in these patients accurately.

Colorectal adenomas containing invasive carcinoma. Pathologic assessment of lymph node metastatic potential

Adenomas that contain early invasive carcinoma (ACIC) represent the earliest form of clinically relevant cancer of the colorectum in most patients. In order to assess the incidence of nodal metastases of ACIC, we studied 31 patients in whom the colon was resected after endoscopic polypectomy (EP) done from 1975 to 1987. We also reviewed the pathologic features reported in individual cases and in literature series of ACIC with lymph node metastases published from 1958 to 1986. The lymph node metastatic potential of ACIC is relatively high, ranging from an average value of 8.5% in the literature of to 16.1% in our own study, and is equivalent to the range of 10%-17% that occurs in colorectal carcinomas that invade the submucosa. When an ACIC is seen in an EP specimen in which the polypectomy margin is normal, the decision as to whether the patient should enter a follow-up protocol or have radical surgical resection is determined by the assessment of the probability of the occurrence of nodal metastases. According to several authors, certain histopathologic features make it possible to distinguish between an ACIC with a high-risk of nodal metastases versus those with a low-risk. The most relevant pathologic parameters include the state of the resection margins, the grade of the invasive carcinoma, and the presence or absence of vascular invasion. Of 351 cases of ACIC that were operated on, derived from 16 literature series, 45.6% were high-risk cases and 8.5% had lymph node metastases. In our group of high-risk ACIC that had surgical resection subsequently, the lymph node metastatic rate was 35.7%. Our results help to estimate the nodal metastatic potential of early colorectal carcinomas and stress the importance of adequate pathologic evaluation in order to assess metastatic risk in these patients accurately.