Amantadine and equine influenza: pharmacology, pharmacokinetics and neurological effects in the horse

Amantadine is an antiviral agent effective against influenza A viruses. We investigated 1) the antiviral efficacy, 2) analytical detection, 3) bioavailability and disposition, 4) pharmacokinetic modelling and 5) adverse reactions of amantadine in the horse. In vitro, amantadine and its derivative rimantadine suppressed the replication of recent isolates of equine-2 influenza virus with effective doses (EDs) of less than 30 ng/ml. Rimantadine was more effective than amantadine against most viral isolates; we suggest a minimum plasma concentration of 300 ng/ml of amantadine for therapeutic efficacy. In vivo an i.v. dose of amantadine 15 mg/kg bwt produced mild, transient CNS signs which were no longer apparent after 30 min. Amantadine administered at a dose of 15 mg/kg bwt was established as the maximum safe single i.v. dose. However, if repeated i.v. administration of amantadine is required no more than 10 mg/kg bwt t.i.d. should be used. The maximal safe plasma concentration of amantadine was not evaluated but is probably greater than 2000 ng/ml and possibly greater than 4000 ng/ml. On the other hand, horses with lower seizure thresholds, or those on medications that lower seizure thresholds, may be at increased risk of amantadine-induced seizures, which show few premonitory signs and are rapidly fatal. After i.v. administration of amantadine 10 mg/kg bwt, the disposition kinetics were well fitted by a 2-compartment open model. The estimated peak plasma concentration after this dose was about 4500 ng/ml, the volume of distribution at steady-state (Vdss) was (mean +/- s.d.) 4.9 +/- 1.9 l/kg bwt and the beta phase half-life was 1.83 +/- 0.87 h. Computer projections of plasma amantadine concentrations after i.v. administration of amantadine at a dose of 10 mg/kg bwt t.i.d. at 8 h intervals suggest peak plasma concentrations of 4000-5000 ng/ml and troughs of less than 300 ng/ml will be achieved. Amantadine administered orally at 10 mg/kg bwt and 20 mg/kg bwt showed mean oral bioavailability of about 40-60% and a plasma half life of 3.4 +/- 1.4 h; however, there was substantial inter-animal variation in bioavailability. Projections based on the kinetics observed in individual animals suggest that some animals readily maintain effective plasma concentrations of amantadine after oral administration of 20 mg/kg bwt t.i.d. On the other hand, animals in which amantadine is poorly bioavailable may require up to a 6-fold (120 mg/kg bwt) increase in the oral dose to achieve effective blood concentrations. Withholding food for 15 h did not reduce these inter-animal differences in bioavailability. Our results showed that simple dosing with oral amantadine will not yield effective plasma concentrations in all animals. While i.v. administration yielded more reproducible plasma concentrations, care should be taken to see that the seizure threshold is not exceeded. In acute situations, i.v. administration (5 mg/kg bwt) every 4 h should maintain safe and effective plasma and respiratory tract concentrations of amantadine.

[Reversible liver steatosis in patients treated with 5-fluorouracil and interferon-alpha]

Twenty-three patients with metastatic colorectal carcinoma were randomized as part of two multicenter Phase III trials to receive either 5-fluorouracil (5-FU)/interferon alpha-2A (INF-alpha) or 5-FU +/- leucovorin. The patients were evaluated regularly for response by CT of the abdomen when treatment began and then every six to eight weeks. incidentally, we found that four of 13 patients treated with 5-FU/INF-alpha and none of ten patients treated with 5-FU +/- leucovorin developed hepatic steatosis during treatment. The diagnoses were based on a decreased CT value of the liver parenchyma by the repeated CT, and histologically verified by liver biopsies. There was no relationship to cumulative 5-FU or INF-alpha dose. Based on posttreatment CT, the liver parenchyma changes were reversible after therapy was stopped. Recognition of this condition in patients receiving 5FU/INF-alpha is important to prevent a patient from being labeled as having progressive hepatic metastases.

Randomised study of screening for colorectal cancer with faecal-occult-blood test

BACKGROUND

Case-control studies and a voluntary-based follow-up study have suggested that repeated screening with faecal-occult-blood (FOB) tests can lead to a reduction in mortality from colorectal cancer (CRC). The aim of this randomised study was to compare mortality rates after FOB tests every 2 years during a 10-year period with those of unscreened similar controls.

METHODS

140,000 people aged 45-75 years lived in Funen, Denmark, in August, 1985, and were considered for inclusion in our study. Before randomisation we excluded individuals who had CRC or precursor adenomas and those who had taken part in a previous pilot study. Randomisation of 137,485 people in blocks of 14 allocated three per 14 to the screening group (30,967), three per 14 to the control group (30,966), and eight not to be enrolled in the study (75,552). Controls were not told about the study and continued to use health-care facilities as normal. Hemoccult-II blood tests (with dietary restrictions but without rehydration) were sent to screening-group participants. Only those participants who completed the first screening round were invited for further screening--five rounds of screening during a 10-year period. Participants with positive tests were asked to attend to full examination and were offered colonoscopy whenever possible. The primary endpoint was death from CRC.

FINDINGS

Of the 30,967 screening-group participants, 20,672 (67%) completed the first screening round and were invited for further screening; more than 90% accepted repeated screenings. During the 10-year study, 481 people in the screening group had a diagnosis of CRC, compared with 483 unscreened controls. There were 205 deaths attributable to CRC in the screening group, compared with 249 deaths in controls. CRC mortality, including deaths attributable to complications from CRC treatment, was significantly lower in the screening group than in controls (mortality ratio 0.82 [95% CI 0.68-0.99]) p = 0.03).

INTERPRETATION

Our findings indicate that biennial screening by FOB tests can reduce CRC mortality. This study is being continued to improve its statistical power and to assess the effect of the removal of more precursor adenomas in the screening-group participants than in controls on CRC incidence.

Chromosome abnormalities in colorectal adenomas: two cytogenetic subgroups characterized by deletion of 1p and numerical aberrations

Cytogenetic analysis of short-term cultures from 34 benign colorectal polyps, all histologically verified as adenomas, revealed clonal chromosome aberrations in 21 of them. Eight polyps had structural rearrangements, whereas only numerical changes were found in 13. A combination of structural and numerical chromosomal aberrations was found in three polyps. The most common numerical change was gain of chromosome 7, found either as the sole anomaly (five polyps), together with other numerical changes (six polyps), or together with structural rearrangements (two polyps). Other recurrent numerical changes were +20, +13, and monosomy 18, found in six, five, and two adenomas, respectively. Rearrangement of chromosome 1 was the most common structural change. Abnormalities involving 1p were seen in six adenomas, leading to visible loss of material in three. One adenoma had one clone with a large and another with a small 1p deletion. In three adenomas, del(1)(p36) was the only cytogenetic aberration, supporting the authors' previous conclusion that loss of one or more gene loci in band 1p36 is a common early change in colorectal tumorigenesis. Chromosome 8 was involved in structural changes in two adenomas; in one this led to loss of 8p and in the other to gain of 8q. The cytogenetic findings did not correlate in a statistically significant manner with clinicopathologic parameters, such as grade of dysplasia, macroscopic or microscopic adenoma structure, tumor size and location, or the patients' sex and age.

[Intraoperative ultrasonography in colorectal cancer. A prospective, blind study]

This study was designed to compare diagnostic accuracies of measuring liver enzymes, preoperative ultrasonography, surgical examination, and intraoperative ultrasonography for detection of liver metastases from colorectal cancer. A blind prospective comparison between the diagnostic examinations mentioned above were performed in 295 consecutive patients with colorectal cancer. An experienced ultrasonologist performed the preoperative examinations and the results were not known to the other experienced ultrasonologist, who did the intraoperative examinations. The latter was also unaware of the findings by the surgeon. The presence of metastases was further assessed by ultrasonography three months postoperatively, as well as surgery and liver biopsy in some of the patients. The sensitivity of intraoperative ultrasonography (62/64) was significantly superior to that of surgical exploration (54/64), and that of preoperative ultrasonography (45/64). The lowest sensitivity was presented by liver enzymes. "Bilobar" metastases were detected in 42 of 46 patients by intraoperative ultrasonography, but in no more than 33 by the surgeon. Intraoperative ultrasonography demonstrated the highest specificity of all examinations. Intraoperative ultrasonography reduces the number of patients with liver metastases being subjected to superfluous or even harmful liver surgery and it may increase the number in whom liver surgery will prolong life.

Comparison of two techniques of transrectal ultrasonography for the assessment of local extent of polypoid tumours of the rectum

The capability of transrectal ultrasonography (TRUS) to differentiate between benign and malignant rectal polyps was evaluated. Digital palpation and sigmoidoscopy were followed by TRUS with a 7.5-MHz linear-array transducer, in a blinded design. In the second part of the study the procedure was extended with an acoustic window system (AWS), preventing compression of the polyp. Pathological examination after surgical resection was used for definitive diagnosis in 110 polyps. Digital examination detected 10 of 22 carcinomas with adenomas, compared with 19 by TRUS (P < 0.01). However, TRUS falsely indicated 20 of 49 adenomas to be carcinomas, compared with 4 out of 49 by digital examination (P < 0.001). TRUS combined with AWS detected 23 of 24 carcinomas, and gave a false positive result in only 3 of 26 benign polyps. The results suggest that the best way to discriminate between benign and malignant rectal polyps is to combine TRUS with AWS.

Booster vaccination against diphtheria and tetanus in man. Comparison of calcium phosphate and aluminium hydroxide as adjuvants--II

Diphtheria and tetanus antibody levels were measured before and four weeks after booster vaccination of 313 Danish military recruits participating in a clinical trial to compare aluminium hydroxide and calcium phosphate as adjuvants in diphtheria-tetanus vaccines (DT). Twenty-eight percent of the men had a diphtheria pre-vaccination content below a protective level of 0.01 IU ml-1. The calcium phosphate adsorbed vaccine showed the highest efficacy for both antigens. Adverse reactions were rare but more frequent in the calcium group than in the aluminium group. No correlation was found between pre- or post-vaccination levels and adverse reactions and both vaccines gave rise to specific IgE formation. The results show that calcium phosphate is more effective but not a safer alternative to aluminium hydroxide when compared in vaccines containing 1.0 mg ml-1 of Ca or of Al.

Omeprazole in the long-term treatment of gastro-oesophageal reflux disease. A double-blind randomized dose-finding study

BACKGROUND

Omeprazole is effective in the treatment of reflux oesophagitis, and it is important to determine the lower dose limit with still appropriate clinical efficacy.

METHODS

Patients with endoscopic oesophagitis grade 1-4 (N = 220) were randomized to double-blind treatment with 20 mg or 40 mg omeprazole daily for 4-8 weeks. Those healed after this initial treatment phase were re-randomized to double-blind treatment with 20 mg omeprazole daily (n = 67), 10 mg omeprazole daily (n = 68), or placebo (n = 33) for 6 months. Remission was defined as the absence of any endoscopic sign of oesophagitis.

RESULTS

Healing rates were increased with 40 mg omeprazole, the therapeutic gain compared with the 20-mg dose being 15% after 4 and 8 weeks. The proportion of patients in remission after 6 months was 59% with 20 mg omeprazole, 35% with 10 mg omeprazole, and 0% with placebo.

CONCLUSION

Maintenance treatment with 10 mg omeprazole can prevent recurrence of oesophagitis in about one-third of patients with all grades of oesophagitis, and 20 mg omeprazole in about twice as many.

A randomized surveillance study of patients with pedunculated and small sessile tubular and tubulovillous adenomas. The Funen Adenoma Follow-up Study

BACKGROUND

We wanted to assess the influence of various surveillance intervals on the risk of new neoplasia after removal of pedunculated and small sessile tubular and tubulovillous adenomas.

METHODS

After initial colonoscopic polypectomy patients were randomized to surveillance with either 2 years (group A) or 4 years (group B) between colorectal examinations.

RESULTS

The cumulated risk of a patient having new adenomas was 35.0% (28.7-41.4%) in group A and 35.5% (28.4-42.7%) in group B after 48 months. The risk increased to 44.9% (36.0-53.9%) and 60.1% (48.5-71.7%), respectively, after 96 months. The risk of significant neoplasia (carcinoma or adenoma with villous structure, severe dysplasia, or diameter > 10 mm) was 5.2% (2.3-8.1%) and 8.6% (3.8-13.3%) after 48 months and 8.6% (4.2-13.0%) and 17.4% (7.6-27.2%) after 96 months. More than one adenoma at first examination was associated with higher risk of new adenomas. Furthermore, we found a tendency for age above 60 years and male gender to be associated with higher risk of new adenomas. More than two adenomas at first examination was the only factor found to be associated with a higher risk of new significant neoplasia. One patient in group A and two patients in group B developed cancer, which is not significantly different from the number expected (3.43) in the average Danish population (RR = 0.9, 0.2-2.6).

CONCLUSION

After colonoscopy with removal of all polyps, colorectal examination at 4 years resulted in a similar risk of new adenomas compared with examinations at 2 and 4 years. However, new significant neoplasia tended to be more frequent when first surveillance was at 4 years. Extending the surveillance to 8 years also tended to increase the risk more in the group being examined every 4 years, but reduction of the number of surveillance examinations by more than 50% and a probable reduction of complications from surveillance examinations themselves may justify a recommendation for the longest interval.

Reversible hepatic steatosis in patients treated with interferon alfa-2a and 5-fluorouracil

BACKGROUND

Thirty previously untreated patients with metastatic colorectal carcinoma were randomized as part of two multicenter Phase III trials. Twenty-two patients were randomized to receive either 5-fluorouracil (5-FU)/interferon alfa-2A (IFN-alpha) or 5-FU/leucovorin (11 patients in each arm). Eight patients were randomized to receive 5-FU/IFN-alpha or 5-FU alone (4 patients in each arm).

METHODS

Twenty-three patients (13 patients treated with 5-FU/IFN-alpha and 10 patients treated with 5-FU/leucovorin or 5-FU alone) were evaluated regularly for response by computed tomography (CT) scans of the abdomen when treatment began and then every 6-8 weeks.

RESULTS

Incidentally, four patients developed hepatic steatosis during treatment with IFN-alpha and 5-FU. The diagnosis was based on a decreased CT value of the liver parenchyma by repeated CT scans of the abdomen during treatment, and this diagnosis was verified histologically by liver biopsy. There was no relationship to cumulative IFN-alpha or 5-FU dose. Based on posttreatment CT scans, the liver parenchyma changes were reversible after therapy was stopped, and there were no significant clinical sequelae. No patients treated with 5-FU/leucovorin or 5-FU alone experienced a decreased CT value of the liver parenchyma.

CONCLUSION

Hepatic steatosis was been observed in approximately 30% of patients treated with IFN-alpha and 5-FU. The hepatic changes were fully reversible after the treatment was stopped. Recognition of this condition is important to prevent a patient from being labeled as having progressive hepatic metastases.

Intraoperative ultrasonography in detection of hepatic metastases from colorectal cancer

PURPOSE

This study was designed to compare diagnostic accuracies of measuring liver enzymes, preoperative ultrasonography, surgical examination, and intraoperative ultrasonography for detection of liver metastases from colorectal cancer.

METHODS

Blind, prospective comparisons of diagnostic examinations mentioned above were performed in 295 consecutive patients with colorectal cancer. An experienced ultrasonologist performed the preoperative examinations, and results were unknown to the other experienced ultrasonologist who performed the intraoperative examinations. The latter, also was unaware of the findings by the surgeon. The presence of metastases was further assessed by ultrasonography three months postoperatively, as well as additional surgery and liver biopsy in some of the patients.

RESULTS

The sensitivity of intraoperative ultrasonography (62/64) was significantly superior to that of surgical exploration (54/64) and that of preoperative ultrasonography (45/64). The lowest sensitivity was presented by liver enzymes. Bilobar metastases were detected in 42 of 46 patients by intraoperative ultrasonography but in only 33 patients by the surgeon. Intraoperative ultrasonography demonstrated the highest specificity of all examinations.

CONCLUSIONS

Intraoperative ultrasonography reduces the number of patients with liver metastases from being subjected to superfluous or even harmful liver surgery, and it may increase the number in whom liver surgery will prolong life.

[Rectal exploration and transrectal ultrasound scanning of rectal cancer. A prospective, blind study]

Staging of rectal carcinoma before surgical treatment was performed in a prospective blind study, comparing digital rectal exploration and transrectal linear ultrasonography (TRUS) with the resulting pathological examination. TRUS underestimated the depth of penetration in three of 33 patients and overestimated it in nine of 74. The figures for digital examination were five of 18 and 20 of 76, respectively. Penetration of the rectal wall was correctly identified in 56 of 61 patients by digital rectal examination and in 59 of 61 by TRUS. Specimens without penetration of the rectal wall were identified in 26 of 33 patients by TRUS, but in no more than 13 of 33 by digital examination. Regional lymph node metastases were present in 19 patients; none were diagnosed by digital examination, but TRUS identified 11 of the 19. It is concluded that TRUS will result in more patients being given the possibility of curative local surgery.

Karyotypic aberrations in an anal-canal malignant-melanoma and its local metastasis

Tissue samples from a malignant melanoma of the anal canal and its local metastasis were short-term cultured and analyzed cytogenetically. Complex chromosome aberrations were found in the primary tumor, yielding the karyotype 49-50,X,-Y,der(1)t(1;13)(q44;q12),+der(2)t(2;8) (q31;q12),der(6)t(5;6)(q13;q21),+del(6)(q12q21),+7, der(8)t(6;8)(p12;p21),del(11)(p11),der(11)t(11;12) (p15;q24),der(15)t(6;15)(p21;p11-13),+der(20)t(1;20) (q12;q13),der(22)t(11;22)(p11;p11)[34]/88-100,idemx2[3]. In the local metastasis, the same near-tetraploid abnormal clone was detected, indicating that the cell population was clonally stable during tumor progression. This is the first malignant melanoma of the anal canal that has been cytogenetically characterized.

Karyotypic characterization of colorectal adenocarcinomas

Cytogenetic analysis of short-term cultures from 52 primary colorectal adenocarcinomas revealed clonal chromosome aberrations in 45 tumors, whereas the remaining 7 had a normal karyotype. More than 1 abnormal clone was detected in 26 tumors; in 18 of them, the clones were cytogenetically unrelated. The modal chromosome number was near-diploid in 32 tumors and near-triploid to near-tetraploid in 13. Only numerical aberrations were identified in 13 carcinomas, only structural aberrations in 3, and 29 had both numerical and structural changes. The most common numerical abnormalities were, in order of decreasing frequency, gains of chromosomes 7, 13, 20, and Y and losses of chromosomes 18, Y, 14, and 15. The structural changes most often affected chromosomes 1, 17, 8, 7, and 13. The most frequently rearranged chromosome bands were, in order of decreasing frequency, 13q10, 17p10, 1p22, 8q10, 17p11, 7q11, 1p33, 7p22, 7q32, 12q24, 16p13, and 19p13. Frequently recurring aberrations affecting these bands were del(1)(p22), i(8)(q10), i(13)(q10), and add(17)(p11-13). The most common partial gains were from chromosome arms 8q, 13q, and 17q and the most common partial losses from chromosome arms 1p, 8p, 13p, and 17p. A correlation analysis between the karyotype and the clinicopathologic features in our total material, which consists of altogether 153 colorectal carcinomas, including 116 with an abnormal karyotype, showed a statistically significant association (P < 0.05) between the karyotype and tumor grade and site. Carcinomas with structural chromosome rearrangements were often poorly differentiated; well and moderately differentiated tumors often had only numerical aberrations or normal karyotypes. Abnormal karyotypes were more common in rectal carcinomas than in carcinomas situated higher up. Near-triploid to near-tetraploid karyotypes were more than twice as frequent in tumors of the distal colon as in those of the proximal colon and rectum. The cytogenetic data indicate that carcinomas located in the proximal colon and rectum, which often are near-diploid with simple numerical changes and cytogenetically unrelated clones, probably arise through different mechanisms than do tumors located in the distal colon, which more often have complex near-triploid to near-tetraploid karyotypes.

[Rectoscopy and Hemoccult-II as initial diagnosis. A procedure in patients with symptoms of irritable colon]

The diagnostic accuracy for colorectal cancer (CRC) of rigid sigmoidoscopy and faecal occult blood test (Hemoccult-II) (H-II) was investigated in patients with irritable bowel syndrome in general practice in a three year period and the results were compared with those of the previous three years, where rigid sigmoidoscopy and double contrast barium enema (DCBE) were the initial preferred examinations. Colonoscopy was recommended in patients with positive H-II, but also in patients with repeated negative H-II within three months, provided that the symptoms persisted. CRC was detected in 141 of 630 patients with positive H-II and in 52 of 8697 with negative H-II. The number of CRC's in the two study periods was similar, in spite of a pronounced reduction in DCBE's from 12,196 to 5656 and a small increase in colonoscopies from 3053 to 4127. It was concluded that the new strategy was no worse than the previous one and the major savings in DCBE's could be used to exchange the rigid sigmoidoscopy with a 60 cm flexible sigmoidoscopy, increasing diagnostic accuracy, shortening delay of diagnosis and removing more adenomas, which eventually may reduce the future incidence of CRC and thereby the mortality from CRC.

Clonal karyotypic abnormalities in colorectal adenomas: clues to the early genetic events in the adenoma-carcinoma sequence

Cytogenetic analysis of short-term cultures from colorectal adenomas revealed acquired clonal chromosome aberrations in 14 of 17 tumors. In 4 adenomas, only numerical changes were found, whereas 10 had structural rearrangements. Trisomy 7 was found as the sole change in one of the tumors and together with other numerical changes in another. A +7 was also present in one case with structural aberrations. Other recurrent numerical aberrations were -14 and -18, both found in 2 adenomas with structural karyotypic changes; in addition, one chromosome 14 was lost in one of the tumors with only numerical changes. The chromosome most often involved in structural aberrations was chromosome 1. In 6 cases, the rearrangements led to changes in 1p, always with loss of material. The breakpoints were at 1p32-36. One adenoma had deletion of 1p as the only change. Other chromosomes that were involved in changes in more than 2 cases were chromosomes 8, 13, and 17. These rearrangements typically led to gain of 8q and 13q and loss of 17p. The adenomas with structural abnormalities were generally larger and had a higher degree of dysplasia than did the adenomas with numerical changes only or those with a normal karyotype. All adenomas with a tubulovillous or villous architecture had structural rearrangements. Our findings confirm that a subset of colorectal adenomas exists that have only numerical chromosome aberrations. They also support our previous conclusion that loss of material from distal 1p is an early event in colorectal tumorigenesis, but that other cytogenetic aberrations follow and typically are present already at the adenomatous stage.(ABSTRACT TRUNCATED AT 250 WORDS)

Digital rectal examination and transrectal ultrasonography in staging of rectal cancer. A prospective, blind study

Staging of rectal carcinoma before surgical treatment was performed in a prospective blind study, comparing digital rectal exploration and transrectal linear ultrasonography (TRUS) with the resulting pathological examination. TRUS underestimated depth of penetration in 3 of 33 patients and overestimation resulted in 9 of 74. The figures for digital examination were 5 of 18 and 20 of 76, respectively. Penetration of the rectal wall was correctly identified in 56 of 61 patients by digital examination and in 59 of 61 by TRUS. Specimens without penetration of the rectal wall were identified in 26 of 33 patients by TRUS, but in not more than 13 of 33 by digital examination. Regional lymph node metastases were present in 19 patients; none were diagnosed by digital examination, but TRUS identified 11 of the 19. It is concluded that TRUS will result in more patients having the possibility of local surgery for cure.

Digital rectal examination and transrectal ultrasonography in staging of rectal cancer. A prospective, blind study

Staging of rectal carcinoma before surgical treatment was performed in a prospective blind study, comparing digital rectal exploration and transrectal linear ultrasonography (TRUS) with the resulting pathological examination. TRUS underestimated depth of penetration in 3 of 33 patients and overestimation resulted in 9 of 74. The figures for digital examination were 5 of 18 and 20 of 76, respectively. Penetration of the rectal wall was correctly identified in 56 of 61 patients by digital examination and in 59 of 61 by TRUS. Specimens without penetration of the rectal wall were identified in 26 of 33 patients by TRUS, but in not more than 13 of 33 by digital examination. Regional lymph node metastases were present in 19 patients; none were diagnosed by digital examination, but TRUS identified 11 of the 19. It is concluded that TRUS will result in more patients having the possibility of local surgery for cure.

[99mTc anti-carcinoembryonic antigen in colorectal cancer]

This investigation is a part of a phase three multicentre immunoscintigraphy study of a technetium-99m labelled monoclonal antibody (Mab), BW 431/26, directed against carcino-embryonic antigen (CEA). Ten patients with recently colonoscopically verified primary colorectal cancer were evaluated. In nine of ten patients colorectal cancers were detected by wholebody immunoscintigraphy and by single photon emission computerized tomography (SPECT). The ten patients were operated upon, and in nine cases immunohistochemical investigations were performed. Immunohistochemical investigation of nine tumour specimens show that CEA was present in much higher concentrations in the tumour than in normal intestinal epithelium. Active accumulation of the labelled Mab in tumours was demonstrated by scintimetry. There is a demand for new diagnostic techniques for early diagnosis of colo-rectal cancer. Immunoscintigraphy must however compete with other diagnostic possibilities. The development of immunoscintigraphic technique is proceeding very rapidly, and there is probably a future for the use of immunological methods in diagnosis and therapy of cancer.

Tumor detection with 131I-labeled human monoclonal antibody COU-1 in patients with suspected colorectal carcinoma

A major factor limiting the use of rodent monoclonal antibodies for diagnosis and therapy of cancer is the development of human anti-mouse immunoglobulin antibodies. Here we report a phase I/II immunodetection study of a human monoclonal antibody, COU-1, labeled with 131I. COU-1 is produced by a human-human hybridoma and recognizes a M(r) 43,000 cytokeratin-like protein strongly expressed by adenocarcinomas of the colon, breast, and ovary. Ten patients were given an i.v. infusion of 2 mg of antibody COU-1 labeled with 185 MBq of 131I. No adverse effects or toxicity were detected by conventional clinical tests nor by a complement activation assay for C3d. None of the patients developed antibodies against antibody COU-1 as determined by enzyme-linked immunosorbent assay and agglutination analysis. Tumor detection was successful in 7 of 9 cancer patients. The tenth patient proved to be a true negative. In several instances immunoscintigraphy gave additional or more correct information than conventional detection techniques. Tumors were most clearly outlined at days 5 and 7 after infusion. Primary colorectal carcinomas were detected by planar imaging in the cecum, ascending colon, and rectum with the smallest lesion measuring 3.0 cm in diameter. Immunoscintigraphy revealed multiple liver metastases in 1 of 3 patients. However, the livers of all 3 patients contained significantly more radioactivity (P < 0.005) than tumor-free livers of the other patients. Pharmacokinetics was evaluated in all patients. The clearance of 131I-labeled COU-1 from the circulation followed a triphasic pattern; an initial phase [t1/2 = 0.4 +/- 0.4 (SD) h] cleared 23% of the radioactivity followed by a rapid phase with a half-life of 13 +/- 3.8 h. The third phase (beta-phase) exhibited a half-life of 119 +/- 36 h, which is similar to the half-life reported for normal IgM. The human monoclonal antibody COU-1 directed against a predominantly intracellular cancer-associated antigen does not produce toxicity or induce antibody formation and seems to be a promising agent for detecting tumors with immunoscintigraphy.

Effect of stimulation of mucosal HCO3- secretion on acid-induced injury to porcine duodenal mucosa

The effect of stimulation of duodenal mucosal bicarbonate secretion with vasoactive intestinal peptide (VIP) on acid-induced damage to the duodenal mucosa was studied in anaesthetized pigs in which bile and pancreatic juice were diverted from the duodenum. Mucosal damage was quantitatively assessed histologically, and mucosal blood flow was determined by means of radioactively labelled microspheres. Compared with placebo, intravenous infusion of VIP (500 pmol/kg/h) significantly stimulated duodenal mucosal bicarbonate secretion (47 +/- 13 versus 249 +/- 53 mumol/h) without concomitant changes in mucosal blood flow (51.5 +/- 7.8 versus 48.5 +/- 9.1 ml/min/100 g) or arterial bicarbonate concentration (24.2 +/- 1.1 versus 23.4 +/- 0.9 mM). The same dose of VIP increased the acid disappearance rate in the duodenum (2.2 +/- 0.14 versus 3.3 +/- 0.09 mmol/h) and reduced the extent of damage to the duodenal surface (16 +/- 2% versus 7 +/- 2%) during duodenal infusion of 0.03 M HCl but not 0.1 M HCl. We conclude that the protection offered by VIP against the small dose of acid is most likely secondary to the effect of VIP on mucosal bicarbonate secretion. Thus, this study suggests that duodenal mucosal bicarbonate secretion, independent of mucosal blood flow, is an integral factor in duodenal mucosal defence.

The Funen Adenoma Follow-up Study. Incidence and death from colorectal carcinoma in an adenoma surveillance program

The results of a prospective randomized study of 1056 patients with colorectal adenomas are presented. After initial polypectomy from 1978 to 1992, patients were allocated at random to different follow-up intervals varying from 6 to 48 months, except 53 patients who were allocated to intervals of 6 months. The examinations were mainly done by colonoscopy. Ten patients developed colorectal carcinoma, a number similar to that expected (7.96), when compared with a sex- and age-matched normal Danish population. The expected number of carcinomas was also calculated from adenoma to carcinoma conversion rates estimated in other studies and compared with that observed. If all carcinomas develop in large (> or = 10 mm) adenomas or adenomas with severe dysplasia, the expected number of carcinomas would have been 62 and 110, respectively, indicating a significant reduction of carcinomas in the present study. One patient died of colorectal carcinoma, which is significantly lower than the number expected (7.58). Two patients died of complications from therapeutic and diagnostic colonoscopy--that is, 2 deaths in 3959 colonoscopies. In conclusion, the follow-up strategy has resulted in a mortality from colorectal carcinoma which is reduced when compared with the normal population, in spite of an apparently similar incidence of carcinoma. However, previous suggested adenoma-carcinoma conversion rates indicate that a major reduction of incidence actually has taken place.

Deletion of 1p36 as a primary chromosomal aberration in intestinal tumorigenesis

Cytogenetic analysis of short-term cultures from benign intestinal tumors revealed clonal chromosome aberrations in five colorectal adenomas, one adenoma of the papilla Vateri, and one hyperplastic polyp of the rectum. One adenoma had numerical aberrations only, but in all other tumors structural rearrangements were found that led to loss of genetic material from 1p. In three of the cases, the deletion was restricted to the 1p36 band; the rest had lost larger 1p segments. The rearrangement of chromosome 1 was the sole karyotypic anomaly in three adenomas, all with mild or moderate dysplasia, and in the hyperplastic polyp. Both adenomas that had additional aberrations beyond the 1p loss showed severe dysplasia. We conclude that cytogenetically detectable loss of genetic information from 1p36 is an early, seemingly primary, premalignant event in intestinal tumorigenesis. The fact that the adenomas with 1p- as the sole change showed only mild or moderate dysplasia and that the del(1p) was found also in the hyperplastic polyp suggests that this aberration is more related to the induction of hyperproliferation than to differentiation disturbances in the intestinal mucosa.

[Liver disease in erythropoietic protoporphyria]

In erythropoietic protoporphyria, the genetically determined decreased activity of the enzyme ferrochelatase causes accumulation of the photoreactive molecule protoporphyrin in various tissues. Dermatological symptoms are dominant, but in some patients the excess protoporphyrin affects hepato-biliary structures, and a spectrum of changes, which ranges from ultrastructural bile canalicular damage to cirrhosis, can be observed. Most clinical reports have described severe cases with a rapid deterioration and a fatal outcome. We present a case with spontaneous recovery from hepatic decompensation on two occasions with three years interval. The first incidence might have been provoked by hormonal substitution therapy.

The Funen Adenoma Follow-Up Study. Characteristics of patients and initial adenomas in relation to severe dysplasia

Between 1978 and 1992 a total of 1689 colorectal adenomas were removed in 1042 patients with no history of previous colorectal neoplasms. One hundred and eighteen patients had at least one adenoma with severe dysplasia. A 'clean colon' was ensured by total colonoscopy in 97% of the patients. A multiple logistic model was used to assess the independent risk factors associated with severe dysplasia. The size of largest adenoma and the extent of villous component were identified as independent patient risk factors associated with high risk of severe dysplasia. The results indicated that the risk of severe dysplasia is high in patients with large and/or villous adenomas and the risk is even higher when the adenomas are found in the sigmoid colon or rectum.

Observer homogeneity in the histologic diagnosis of Helicobacter pylori. Latent class analysis, kappa coefficient, and repeat frequency

Four pathologists independently examined 82 antral mucosal biopsy specimens for the presence of Helicobacter pylori and indicated whether their assessments were certain. The pathologists made a positive diagnosis in from 56% to 84% of the specimens (significant heterogeneity, p < 0.01). The frequency of uncertain diagnoses was from 4% to 20% (p < 0.01). Uncertain statements occurred more frequently among negative than among positive diagnoses. For the six pairs of observers the kappa coefficients were between 0.39 and 0.82. By a latent class analysis measures of diagnostic accuracy were calculated comparing the observers' assessments with an estimated consensus diagnosis. The predictive values of a positive diagnosis ranged from 0.70 to 1.00. By calculation of repeat frequencies--that is, the probability that an observer's statement was confirmed by another observer--it became evident that uncertain statements were less frequently (61%) confirmed than were certain ones (85%). It is concluded that observer homogeneity is only moderate with regard to the histologic diagnosis of H. pylori, which should be considered both in daily clinical routine and in scientific studies. Disagreement between observers was associated with negative diagnoses, presumably because the pathologists felt more uncertain in these cases.

Interval cancers in screening with fecal occult blood test for colorectal cancer

Interval cancers, which are cancers diagnosed in spite of one or more negative screening tests, were studied in a randomized population with Hemoccult-II for colorectal cancer in 61,938 persons between 45 and 74 years old. Three biannual screenings were performed from 1985 to 1991, and 52% of all the cancers detected after doing at least one Hemoccult-II test were interval cancers (81 persons). These were more advanced than cancers diagnosed after a positive Hemoccult-II test, of larger size, less frequently of Dukes stage A, more often invading neighboring organs, and less often resectable for cure. They were located in the rectum more often than cancers diagnosed by screening and cancers in controls. Otherwise, interval cancers did not differ from cancers in controls or cancers in non-responders, and all characteristics suggested that no delay in diagnosis resulted from one or more negative Hemoccult-II tests, compared with controls. However, even if screening with Hemoccult-II demonstrates a reduction in mortality from colorectal cancer, the present high number of interval cancers makes it necessary to look for other methods of screening populations for colorectal cancer.

Can Hemoccult-II replace colonoscopy in surveillance after radical surgery for colorectal cancer and after polypectomy?

Surveillance after colorectal carcinoma and adenoma includes colonoscopy, which is a demanding procedure for the patient, doctor, and society. Therefore, it was investigated whether a simple fecal occult blood test could replace colonoscopy. Hemoccult-II (H-II) was performed before 1,244 colonoscopies in patients with previous cancer and before 328 colonoscopies in an adenoma surveillance program. The H-II test was positive in 3 of 9 patients with local recurrence, in 2 of 13 with metachronous cancer, and in 31 of 186 with adenomas. The test was positive more often in patients with large and multiple adenomas, sigmoid adenomas, and adenomas with villous elements and moderate-to-severe dysplasia, but the sensitivity did not reach more than 25 to 40 percent. It was concluded that markers more sensitive than H-II are needed to detect metachronous cancers and new adenomas. In the meantime, colonoscopy has to be used with intervals of several years, but not for detection of local recurrent cancer, which in most cases may be found by simpler means.

Echo pattern of lymph nodes in colorectal cancer: an in vitro study

Surgical specimens from 75 patients with colorectal cancer were examined within 15 min of removal with a 7.5 MHz linear-array transducer. The echo pattern of 139 lymph nodes was analysed to evaluate previous criteria of malignancy and to establish other possible criteria, which could be tested in vivo. The pathologist examined each node without knowledge of the sonographic finding. Malignant nodes were larger than benign nodes. Of 21 nodes less than 5 mm in diameter, 20 were benign. Round nodes were malignant more often (45/78) than ovoid nodes (6/61). A homogeneous echo pattern was associated with malignancy in 39 of 82 nodes in contrast to 12 of 57 with a heterogeneous pattern. Thirty-one nodes were ovoid as well as heterogeneous and all of these were benign. A hyperechoic centre was found in 14 nodes of which two were malignant. The highest predictive value for malignancy (59%) was obtained by combining the discriminative properties of shape, homogeneity and echogenicity.

Causes of death during the first 5 years of a randomized trial of mass screening for colorectal cancer with fecal occult blood test

The main purpose of population screening for colorectal cancer is to reduce mortality from the disease. The criteria of death from colorectal cancer are defined in the present randomized trial of 61,938 persons between 45 and 74 years old, and the need for an impartial death review committee was demonstrated. Causes of death within the first 5 years are described within subgroups of the test group and compared with those in the control group. Death rates were higher among non-responders to screening than among controls and among those in whom Hemoccult-II had been performed at least once. Persons with negative Hemoccult-II had a lower death rate than controls. The overall autopsy rate was 32%. Lethal complications from treatment of colorectal neoplasia were evaluated per se. Death from colorectal cancer occurred in 74 persons in the total screening group and in 91 among controls. Sources of bias are discussed. A method of evaluating possible benefit to those being screened is suggested. Final results cannot be expected before 1996.

Anal neoplasia and its precursors: facts and controversies

The normal anal mucosa shows a complex histology, and a large variety of tumors and lesions with more or less malignant potential may arise in this region. Several of these seem to be related to venereal diseases, homosexual behavior, and anal intercourse, and to immunosuppression. Human papilloma virus (HPV) has been identified in many cases, but the relation to the histological picture is not constant and the significance is unclear. However, these observations have helped us to identify risk groups. Histological classification is often difficult and it is likely that the reproducibility is limited. This may, in part, explain different observations with regard to frequency and biological behavior. A reliable diagnosis still largely depends on exact clinical information on location and appearance, detailed knowledge of the normal histology, and careful handling of the specimen. The revised World Health Organization (WHO) classification represents an improvement, but more variants are still identified and a classification based on conventional histology alone seems in many cases unsatisfactory. Immunohistochemistry and hybridization and other techniques hopefully will provide us with improved typing of these lesions.

[Curative local excision of colorectal cancer. A prospective study]

The importance of local treatment for early colorectal cancer is apparent because of increasing endoscopical activity for diagnostic purposes and screening. Curative local treatment was attempted in 63 patients with polypoid, mobile tumours thought to be within the bowel wall and without palpable lymph nodes in the perirectal tissue. Tumours more than 3 cm in diameter were excluded, unless they were pedunculated or were believed to be adenomas with carcinoma. Removal was effected by polypectomy, piecemeal removal, peranal excision, posterior rectotomy or colotomy. Complications were few, and hospitalization was shorter than after conventional surgery, but one patient died from treatment. More extensive surgery followed in 12 patients, in whom cancer remained in the resection margin or where this could not be excluded. However, seven of the 12 patients had no residual cancer tissue. Survival without recurrence was longer in patients with tumours below 3 cm in diameter. Recurrence was seen in nine patients, but not in those with cancer limited to head and the stalk of pedunculated tumours and not with cancer limited to the luminal part of submucosa, regardless of shape of tumour. Adenoma in continuity with cancer did not influence survival significantly, but synchronous adenomas in other parts tended to increase recurrence-free survival. Local treatment is satisfactory in most patient with cancer within pedunculated polyps and in some with cancer in sessile polypopid tumours. Criteria of selection are not optimal and the use of endoluminal ultrasound examinations must be evaluated in prospective trials. At present, conventional surgery should be used when cancer in the resection margin cannot be excluded, when cancer is present in the deeper layers of muscularis propria and in patients with poorly differentiated cancers.

Melanocytes in the anal canal epithelium

We studied the presence of melanocytes in the various epithelial zones of the anal canal, using a recently introduced melanocyte-specific antibody (HMB-45) together with antibody to S-100 protein. In normal and canals and in haemorrhoids, melanocytes, defined as intraepithelial HMB-45/S-100 positive cells, were frequently demonstrated in the anal squamous zone, only sporadically in the anal transitional zone, and not at all in the colorectal zone. In the epithelium surrounding, but clearly separated from, resected primary anal malignant melanomas, increased numbers of benign melanocytes were demonstrated in the squamous zone and transitional zone, but also in the colorectal zone. We interpret this finding as a tumour-induced proliferation of benign melanocytes normally present, but in very small numbers or in some way 'masked', in the epithelium of the upper anal canal. The demonstration of melanocytes in all three zones of the anal canal substantially supports the observation that malignant melanoma of the anal canal may originate not only below but also above the dentate line.

[Colonoscopy after radical surgery for colorectal cancer. A 10-year prospective study of 309 patients]

Experience from ten year colonoscopic follow-up in patients after radical surgery for colorectal cancer is presented. In all, 309 patients below 76 years were included from 1978 to 1983. All had preoperative proctoscopy and barium enema. Colonoscopy was performed perioperatively, every six months the first three years, four and five years, seven to eight years and ten years after surgery. A minority had double-contrast barium enemas. Synchronous adenomas were removed during surgery and at perioperative colonoscopy and these patients had the same risk of metachronous cancer as those without synchronous adenomas. Five patients with six metachronous cancers, all had new curative surgery. Patients with synchronous adenomas had a higher risk of metachronous adenomas, but had a better prognosis than those without synchronous adenomas. Colonoscopically demonstrated intraluminal local recurrence in the colon could not be treated with new radical surgery in contrast to four out of eight intraluminal recurrences in the rectum. Most local recurrences were extraluminal and were diagnosed by other means.

Adenomas and hyperplastic polyps in screening studies

A survey is given of colorectal polyps detected in a prospective randomized screening study with the fecal occult blood test. It is demonstrated that colonoscopy in persons with positive Hemoccult-II tests results in detection of and removal of a higher number of adenomas than among controls. The strategy may, therefore, possibly be followed by a reduction of the incidence of colorectal cancer. Screen-detected adenomas were most often in males and were larger than among controls; they were most often in the sigmoid colon, whereas the rectum was the most frequent location for adenomas in controls. Eight percent of persons with screen-detected adenomas had some symptoms, which could be referred to adenomas, in contrast to 50% among controls. Hyperplastic polyps served as markers for adenomas in persons with positive Hemoccult-II as well as in controls with adenomas detected by colonoscopy; however, most persons with adenomas had no hyperplastic polyps. Endoscopic polypectomy did not result in any severe complications, but surgical removal in 2 of 22 patients proved fatal. The results presented are compared with those of other prospective randomized trials. The optimistic view--that the incidence of cancer may be reduced by polypectomy in persons with positive Hemoccult-II tests--stresses the importance of securing optimal colonoscopy service.

[Rectoscopy and Hemoccult II in irritable colon. A prospective study]

It was investigated whether Hemoccult-II test (H-II) could reduce the number of colonic examinations in patients with the irritable bowel syndrome, with normal rigid proctoscopic findings. A negative H-II was obtained in 299 patients from general practice and a positive test in nine. Colonoscopy was done in 157 and double contrast barium enema in 142 after random allocation. The nine patients with positive H-II all had colonoscopy. Among the 299 with negative H-II, colonic adenomas were detected in ten and an early cancer in an adenoma in the sigmoid colon; overlooked rectal adenomas were found in three, rectal cancer in one, rectal carcinoid in another and a coecal cancer, which could be palpated, in a third patient. Two patients with colonic cancer and one with adenoma were detected among those with positive H-II. All patients were followed by clinical examination after one year. In conclusion, colonic examination should carry a low priority in patients with symptoms of irritable bowel, negative Hemoccult-II and normal rigid proctoscopic findings performed by an experienced examiner. The investigation confirmed the recommendation of total colonoscopy in patients with a positive H-II and added support for increasing number of endoscopy services in contrast to those of diagnostic radiology, which should be reduced.

Neuronal hyperplasia in the anal canal

In a consecutive series of minor surgical specimens from the anal canal, neuronal hyperplasia was found in nine of 56 haemorrhoidectomy specimens and in four of 23 fibrous polyps. In an additional series of 14 resections of the anal canal, neuronal hyperplasia was present in six cases, of which five showed haemorrhoids. In all cases, neuronal hyperplasia was located in the submucosa beneath squamous epithelium and extended over an area from 5 to 12 mm. Immunohistochemically, the foci of hyperplasia were found to consist of both neuronal and Schwann cell components. Staining for vasoactive intestinal peptide, neuropeptide Y and calcitonin gene related peptide, did not demonstrate any increased terminal density. It is suggested that anal neuronal hyperplasia in these cases represents an acquired lesion due to local mechanical influence.

Observer reproducibility in grading dysplasia in colorectal adenomas: comparison between two different grading systems

The two most well known and well defined grading systems for dysplasia in colorectal adenomas were compared with regard to reproducibility. The Konishi-Morson system (KMS) operates with several histological and cytological variables and grades of mild, moderate, and severe dysplasia. The Kozuka system is based on the extent of nuclear pseudostratification and also has three grades of dysplasia (III-V). As the group of severe dysplasia is very large in this system, it was extended with two higher grades, similarly based on individual histological criteria, known hereafter as the extended Kozuka system (EKS). Fifty six adenomas were graded by two observers, each observer grading twice according to the KMS criteria and twice according to EKS criteria. Intraobserver reproducibility was excellent for the KMS and moderate for the EKS, but this was not significant. The overall interobserver reproducibility was similar (moderate) for the KMS and for the EKS. Kappa values for interobserver reproducibility on individual categories were excellent for severe dysplasia according to the KMS, but low for all other categories in both systems. By simplifying both systems into two groups a high reproducibility can be obtained, but this implies that all the original grades (III-V) for the EKS must be grouped together. It is therefore recommended that a simplified KMS is used for further studies on the biological importance of dysplasia and for comparison between histological changes and other markers for colorectal neoplasia.

Repeated screening for colorectal cancer with fecal occult blood test. A prospective randomized study at Funen, Denmark

Two screenings with Hemoccult-II were performed in a randomized study, allocating 30,970 persons to screening and 30,968 as controls in a population of 140,000 between 45 and 74 years old on the island of Funen, Denmark. The test was completed in 20,672 initially and in 18,779 of these during rescreening 2 years later. Positive H-II tests were found in 215 and 159 persons during the two screenings, respectively. A total colonoscopy was performed in 187 and 144, and cancer was detected in 37 and 13 and adenomata in 86 and 76, respectively. Interval cancers had developed in 40 persons at the end of the second screening, and 39 non-responders had developed cancer. Cancer was diagnosed in 115 controls and an adenoma in 100 during the same period. Interval cancers presented as rectal cancers more frequently than those detected by screening. Early cancers were more frequent in the screening group, and, accordingly, more patients had curative and also less extensive surgery, with a low postoperative mortality. The total number of deaths from colorectal cancer was 37 in the screening group, including interval cancers and cancers in non-responders and persons who developed cancer before they could be invited, which suggests a reduction in mortality of 27% (51 deaths among controls, compared with 37). The reduction is as yet not statistically significant, and final evaluation must await at least one more screening, ending in 1990, and a follow-up of some years. Removal of more large adenomas during screening makes it possible that the incidence of cancer will decrease.

[Prognosis in synchronous liver metastasis from colorectal cancer. A multicenter study of patients with cancer of the rectum and cancer of the rectosigmoid colon]

A prospective investigation of 188 patients with cancer of the rectum and rectosigmoid colon with synchronous liver metastases is described. The mean survival time for 183 patients who did not receive any treatment for the liver metastases was six months and only one survived for longer than 37 months. After extirpation of the primary tumour, the most significant prognostic factors were etrahepatic metastases, enlarged liver on account of metastases and more than three liver metastases. Serum basic phosphatases had the greatest significance among a series of laboratory tests. In the sub-groups with the best possible prognoses, the mean survival time was 12 months. 25% five-year survival has been described in the literature following resection of the liver in patients with a maximum of three metastases, no other metastases and age under 70 years. Provided this holds true, liver surgery will be a therapeutic possibility in at least 100 patients per annum in Denmark with synchronous liver metastases and 25 of these will be cured. This figure requires an improved programme for the diagnosis of synchronous liver metastases than at present and the same high frequency of extirpation of the primary colorectal cancer on a national basis which was achieved in the present material.

Can hairspray be used as a smear fixative? A comparison between two types of coating fixatives

Pairs of smears from 25 consecutive women undergoing routine screening and 30 consecutive colposcopy patients suspected of having cervical intraepithelial neoplasia were randomized and fixed with either Merckofix or a hairspray to compare their use as coating fixatives. Vacuolated cells from the cervical transformation zone were present in 9 of 25 and 24 of 30 smears fixed with hairspray against 2 of 25 and 2 of 30 of smears fixed with Merckofix in the two series, respectively. These findings indicate that the fixative effect of commercial hairsprays always should be tested before such hairsprays are introduced into routine procedures.