Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Risk of Synchronous and Metachronous Colorectal Cancer: Population-Based Estimates in Denmark with Focus on Non-Hereditary Cases Diagnosed After Age 50

BACKGROUND AND AIMS

The risk of synchronous and metachronous colorectal cancer is influenced by heritable and environmental factors. As a basis for comparative studies, we provide population-based estimates of synchronous and metachronous colorectal cancer with a focus on non-heritable cases.

MATERIAL AND METHODS

Based on data from national Danish cancer registers, we estimated the proportion of synchronous colorectal cancer and the incidence rates and risks for metachronous colorectal cancer in 28,504 individuals, who developed 577 metachronous colorectal cancer above age 50.

RESULTS

Synchronous colorectal cancer was diagnosed in 1.3% of the cases. The risk of metachronous colorectal cancer was associated with sex, tumor location, and age with the strongest influence from the latter. The incidence rate ratios for metachronous colorectal cancer ranged from above 6 in patients below age 65 to <1-3.2 in patients above age 65. The absolute risk of metachronous colorectal cancer was ⩾10% in patients below age 65 and 1.0%-8.0% in patients above age 65.

CONCLUSION

Individuals who develop sporadic, non-inherited colorectal cancer above age 50 are at a significantly increased risk of metachronous colorectal cancer with risk estimates that are strongly affected by age. This observation underscores the need for development of targeted surveillance in the most common clinical subset of colorectal cancer.

Cervical Cancer Screening for Patients on the Female-to-Male Spectrum: a Narrative Review and Guide for Clinicians

Guidelines for cervical cancer screening have evolved rapidly over the last several years, with a trend toward longer intervals between screenings and an increasing number of screening options, such as Pap/HPV co-testing and HPV testing as a primary screening. However, gynecological recommendations often do not include clinical considerations specific to patients on the female-to-male (FTM) spectrum. Both patients and providers may not accurately assess risk for HPV and other sexually transmitted infections, understand barriers to care, or be aware of recommendations for cervical cancer screening and other appropriate sexual and reproductive health services for this patient population. We review the evidence and provide guidance on minimizing emotional discomfort before, during, and after a pelvic exam, minimizing physical discomfort during the exam, and making adaptations to account for testosterone-induced anatomical changes common among FTM patients.

Knowledge and attitudes about hepatitis C virus (HCV) infection and its treatment in HCV mono-infected and HCV/HIV co-infected adults

Hepatitis C virus (HCV) treatment is rapidly changing but little is known about patients' attitudes and knowledge about HCV. This study used a cross-sectional survey to examine the relationship between HCV knowledge and attitudes towards HCV in patients with HCV mono-infection and HIV/HCV co-infection. Subsequently, an education intervention was developed with an abridged version of the cross-sectional survey administered before and after the education session to assess changes in knowledge and attitudes. 292 people participated in the cross-sectional survey, and 87 people participated in the education intervention. In the cross-sectional survey, the mean knowledge score regarding HCV was low (<50% of the total possible score). Mono-infected and co-infected individuals shared similar knowledge deficits and attitudes towards HCV despite having distinct demographic differences. Attitudes endorsed by patients included the following: 57% feared the consequences of HCV on their life, 37% felt HCV was not fatal, 27% did not believe they needed HCV medication, 21% felt ashamed of having HCV and 16% felt HCV treatment was not important. Attitudes that reflected indifference and shame towards HCV were associated with lower knowledge scores (HCV knowledge score of 15.1 vs. 17.5, P < 0.01 for indifference and 15.3 vs. 17.2 for shame, P = 0.02). The education intervention improved knowledge scores but did not modify the assessed attitudes. Intervention studies are needed to effectively change attitudes towards HCV infection and treatment.

Genetic profiles of hereditary nonpolyposis colorectal cancer

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Background: With the aim to identify genetic markers of hereditary nonpolyposis colorectal cancer (HNPCC), we applied tiling BAC array-based comparative genomic hybridization (aCGH) to 46 HNPCC-associated colorectal cancer.

Methods: 32 k iling BAC arrays were used to generate high-density genomic profiles. Tumors were selected through a case-control design with half of the tumors derived from individuals with disease-predisposing mismatch repair gene mutations and the reminder from phenotypic HNPCC families without identified mutations. In addition, an equal number of sporadic tumors were used for comparison.

Results: Tumors with disease-predisposing germline mutations showed frequent gains of chromosomes 1p (39%), 17 (43%), 19 (57%) and 22q (30%). HNPCC associated tumors without mutations did as a group have more complex alterations with the most frequent changes being gains of 20q (70%), 19 (35%), 17 (26%) and loss of 18 (39%). Gains of 1p and 20q and loss of chromosome 18 were identified as significant discriminators between HNPCC tumors with/without germline MMR gene mutations.

Conclusions: The aCGH profiles of HNPCC-associated colorectal cancer suggest that specific gains and losses may be used to distinguish between tumors with/without germline mismatch repair gene mutations.

No significant financial relationships to disclose.

Guidelines for the clinical management of familial adenomatous polyposis (FAP)

Familial adenomatous polyposis (FAP) is a well-described inherited syndrome, which is responsible for <1% of all colorectal cancer (CRC) cases. The syndrome is characterised by the development of hundreds to thousands of adenomas in the colorectum. Almost all patients will develop CRC if they are not identified and treated at an early stage. The syndrome is inherited as an autosomal dominant trait and caused by mutations in the APC gene. Recently, a second gene has been identified that also gives rise to colonic adenomatous polyposis, although the phenotype is less severe than typical FAP. The gene is the MUTYH gene and the inheritance is autosomal recessive. In April 2006 and February 2007, a workshop was organised in Mallorca by European experts on hereditary gastrointestinal cancer aiming to establish guidelines for the clinical management of FAP and to initiate collaborative studies. Thirty-one experts from nine European countries participated in these workshops. Prior to the meeting, various participants examined the most important management issues according to the latest publications. A systematic literature search using Pubmed and reference lists of retrieved articles, and manual searches of relevant articles, was performed. During the workshop, all recommendations were discussed in detail. Because most of the studies that form the basis for the recommendations were descriptive and/or retrospective in nature, many of them were based on expert opinion. The guidelines described herein may be helpful in the appropriate management of FAP families. In order to improve the care of these families further, prospective controlled studies should be undertaken.

Screening for urinary tract cancer with urine cytology in Lynch syndrome and familial colorectal cancer

AIM

The aim of this study was to evaluate if Urine Cytology (UC) is an appropriate screening procedure for detecting urinary tract neoplasia at an early stage in persons at risk in Hereditary Non-Polyposis Colorectal Cancer families.

METHOD

In the National Danish HNPCC-register persons at risk were identified in three categories of HNPCC-families (1) families harbouring a disease causing mutation in a Mismatch repair gene (MMR), (2) families fulfilling the Amsterdam I or II criteria and (3) families suspected of HNPCC. In total 3,411 persons were identified and traced in Patobank-the National Danish Pathology database. All UC and UTC (Urinary Tract Tumours) were listed and evaluated.

RESULTS

977 persons had a total of 1,868 screening procedures performed. Two of these procedures (0.1%) lead to diagnosis of an asymptomatic urothelial tumour. In ten times as many procedures (22 persons) UC lead to a false positive screening diagnosis. During the study period fourteen persons (1.4%) developed a UTC and five of these were interval tumours. The sensitivity of UC in diagnosing asymptomatic UTC in HNPCC patients was 29%. Twelve of the tumours were found in persons from families with a proven MMR-mutation and eleven out of these were MSH2 mutations (92%, 95% cl 62-100%).

DISCUSSION

UC is not a proper method of screening for UTC in HNPCC. However, the study can not reveal if screening for UTC in special families ought to be recommended. Consequently, further studies needs to be performed in order to evaluate an appropriate screening programme.

Guidelines for the clinical management of Lynch syndrome (hereditary non-polyposis cancer)

Lynch syndrome (hereditary non-polyposis colorectal cancer) is characterised by the development of colorectal cancer, endometrial cancer and various other cancers, and is caused by a mutation in one of the mismatch repair genes: MLH1, MSH2, MSH6 or PMS2. The discovery of these genes, 15 years ago, has led to the identification of large numbers of affected families. In April 2006, a workshop was organised by a group of European experts in hereditary gastrointestinal cancer (the Mallorca-group), aiming to establish guidelines for the clinical management of Lynch syndrome. 21 experts from nine European countries participated in this workshop. Prior to the meeting, various participants prepared the key management issues of debate according to the latest publications. A systematic literature search using Pubmed and the Cochrane Database of Systematic Reviews reference lists of retrieved articles and manual searches of relevant articles was performed. During the workshop, all recommendations were discussed in detail. Because most of the studies that form the basis for the recommendations were descriptive and/or retrospective in nature, many of them were based on expert opinion. The guidelines described in this manuscript may be helpful for the appropriate management of families with Lynch syndrome. Prospective controlled studies should be undertaken to improve further the care of these families.

Aneurysma spurium und verz�gerte Blutungskomplikation durch ein sekund�r disloziertes Trochanter-minor-Fragment bei pertrochant�rer Femurfraktur

A 92-year-old woman incurred an unstable pertrochanteric hip fracture with avulsion of the lesser trochanter (type 31-A2 according to the AO classification). The fracture was treated by gliding nail osteosynthesis, without fixing the minimally displaced lesser trochanter. No intra- or postoperative complications were detected. Suddenly, after 30 days, a swelling of the proximal femoral region, accompanied by signs of haemorrhage, occurred.CT-scans showed a false aneurysm of the deep femoral artery and a dorsal laceration of the artery proximal to the aneurysm. X-rays showed a further dislocation with rotation of the lesser trochanter fragment. Intraoperatively, the tip of the lesser trochanter fragment was identified to be responsible for the laceration of the artery. The false aneurysm was resected and the defect bridged by a vascular prosthesis while the fragment was removed. Follow-up showed no further complications. According to case reports from the literature, false aneurysms and laceration of the deep femoral artery caused by dislocated lesser trochanter fracture fragments are rare.

The clinical features of ovarian cancer in hereditary nonpolyposis colorectal cancer

OBJECTIVE

Hereditary nonpolyposis colorectal cancer (HNPCC) is a hereditary cancer susceptibility disorder associated with a very high risk for carcinoma of the colon and an elevated risk for certain extracolonic cancers including ovarian cancer. Our aim in this study was to describe the clinicopathologic features of ovarian cancer in HNPCC family members.

METHODS

. Members of the International Collaborative Group on HNPCC collected retrospective data on 80 ovarian cancer patients who were members of HNPCC families, including 31 known mutation carriers, 35 presumptive carriers (by colorectal/endometrial cancer status), and 14 at-risk family members.

RESULTS

Mean age at diagnosis of ovarian cancer was 42.7. Nonepithelial tumors made up only 6.4% of the cancers, and borderline tumors comprised just 4.1% of the epithelial cancers. Among frankly malignant epithelial cases, most cancers were well or moderately differentiated, and 85% were FIGO stage I or II at diagnosis. Synchronous endometrial cancer was reported in 21.5% of cases.

CONCLUSIONS

Ovarian cancer in HNPCC differs from ovarian cancer in the general population in several clinically important respects. It occurs at a markedly earlier age. It is more likely to be epithelial. If it is a frankly invasive epithelial cancer, it is more likely to be well or moderately differentiated. HNPCC patients with ovarian cancer are more likely to have a synchronous endometrial cancer than other ovarian cancer patients and are more likely to be diagnosed at an early stage.

Regional hemodynamic adaptation during the menstrual cycle

OBJECTIVE

To determine whether regional differences exist in uterine and systemic hemodynamic responses to the menstrual cycle, whether the hormonal environment correlates with the changes, and whether uterine artery hemodynamic adaptation depends on the side of ovulation.

METHODS

Twenty nulliparas had transvaginal Doppler ultrasonographic assessment of the uterine and upper-extremity radial arteries at three time points in each of two menstrual cycles. Doppler indices (peak systolic velocity, end-diastolic velocity, time-averaged maximum velocity, resistance index [RI], and blood flow) were measured in the radial and uterine arteries. Women were examined in the menstrual (cycle day 2-3), follicular (cycle day 9-10), and luteal phases (cycle day LH surge plus 9-10). At each time, serum estradiol (E2) and progesterone were measured by radioimmunoassay. Statistical analyses were repeated-measures analysis of variance and the Fisher least significant difference procedure.

RESULTS

Thirty-four nonconception ovulatory cycles were evaluated. Blood flow in each uterine artery increased significantly from a mean (+/- standard deviation) of 22.4 +/- 7.3 mL/minute in the follicular phase to 30.7 +/- 13.7 mL/minute in the luteal phase, which coincided with a reduction in the RI. The changes were independent of the side of ovulation. The radial artery did not parallel these changes (follicular blood flow of 27.2 +/- 13.9 mL/minute; luteal blood flow of 24.7 +/- 10.5 mL/minute). We did not identify any significant correlation between these changes and serum E2 or progesterone concentrations.

CONCLUSION

We identified differences in the hemodynamic responses of the uterine artery compared with the radial artery during the menstrual cycle. We believe the difference indicates distinct regional control of vascular response during the menstrual cycle.

Prenatal diagnosis of the fetal Rhc genotype from peripheral maternal blood

OBJECTIVE

To determine the fetal Rhc genotype by using the polymerase chain reaction (PCR) amplification procedure and maternal blood at the different steps of the fetal cell enrichment process.

METHODS

Maternal peripheral venous blood samples were obtained from 11 pregnant women homozygous for the C antigen before amniocentesis. Three were not alloimmunized and eight were alloimmunized. The fathers were known to be heterozygous or homozygous for the c antigen by serologic testing. The mononuclear cell layer was isolated from maternal blood and flow sorted using monoclonal antibodies to CD36 or CD71 and glycophorin A. This was followed by PCR of the blood, mononuclear cells, and the sorted cells with allele-specific primers to RhCc genes. Gel electrophoresis was performed to predict fetal Rhc genotype. The fetal RhCc genotype was confirmed by serologic and DNA testing.

RESULTS

All infants were positive for the Rhc gene. The positive fetal Rhc genotype was determined correctly in three of the 11 maternal blood samples without enrichment, in six of the nine mononuclear cell samples, and in seven of the eight sorted cell samples. The fetal genotype from one sorted sample was predicted to be homozygous C. One infant was determined by serology on cord blood to be negative for the c antigen, but repeated infant DNA amplification was consistent with the c genotype.

CONCLUSION

Noninvasive fetal Rhc genotyping can be determined by PCR amplification of the rare fetal cells in maternal blood. These data reaffirm that enrichment of maternal blood for fetal cells is necessary to improve the sensitivity of the test.

Reduced frequency of extracolonic cancers in hereditary nonpolyposis colorectal cancer families with monoallelic hMLH1 expression

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant disease caused by mutations in one of at least four different DNA mismatch repair genes, hMLH1, hMSH2, hPMS1, and hPMS2. Phenotypically, HNPCC is characterized by the early onset of colorectal cancers and various extracolonic cancers. Depending on the presence or absence of extracolonic tumors, HNPCG-has been divided into two syndromes (Lynch syndrome I and Lynch syndrome II), but, so far, no correlation to distinct genotypes has been demonstrated. In this study, we present a frequent hMLH1 intron 14 founder mutation that is associated with a highly reduced frequency of extracolonic tumors. The mutation disrupts the splice donor site and silences the mutated allele. Tumors exhibited microsatellite instability, and loss of the wild-type hMLH1 allele was prevalent. We propose that the mutation results in a milder phenotype, because the mutated hMLH1 protein is prevented from exerting a dominant negative effect on the concerted action of the mismatch repair system.

Hereditary non-polyposis colorectal cancer: clinical features and survival. Results from the Danish HNPCC register

BACKGROUND

Hereditary non-polyposis colorectal cancer (HNPCC) is a dominantly inherited syndrome characterized by the development of colorectal cancer (CRC) and other carcinomas. Our aim was to evaluate tumour parameters and survival in HNPCC.

METHODS

One hundred and eight Danish HNPCC patients were compared with 870 patients with sporadic colorectal cancer.

RESULTS

The median age at CRC diagnosis was 41 years in the HNPCC group. HNPCC patients had significantly more carcinomas located to the right colon (68% against 49% in controls), more synchromous tumours (7% versus 1%), more metachronous CRC after 10 years (29% versus 5%), more localized carcinomas (62% versus 39%), and significantly higher crude cumulative 5-year survival (56% versus 30%).

CONCLUSIONS

CRC in HNPCC behaves differently compared to sporadic cases concerning age of onset, frequency of multiple lesions, and location. The metastatic tendency is less than in sporadic CRC and the survival is better.

Anesthetic management of a parturient with an incompletely resected cerebral arteriovenous malformation

BACKGROUND AND OBJECTIVES

The anesthetic, neurosurgical, and obstetric literature regarding management of parturients with intracranial arteriovenous malformations is relatively sparse. A case report is given of a parturient, with a recent subtotal resection of a cerebral arteriovenous malformation, who presented for delivery of a viable male fetus.

METHODS

The patient was scheduled for an elective labor induction, with early epidural analgesia advocated as a strategy to minimize the cardiovascular changes of labor and prevent involuntary Valsalva maneuvers. An elective instrumental delivery was planned when the fetal head had descended appropriately.

RESULTS

Epidural analgesia was initiated when the patient reached 3 cm cervical dilation and provided excellent labor analgesia. After a passive fetal descent during the second stage of labor, Luikart-Simpson forceps were used to facilitate this stage. The newborn Apgar score was 9 at both 1 and 5 minutes after delivery. Both the patient and the infant have done well.

CONCLUSIONS

The available obstetric and neurosurgical literature does not offer firm recommendations for the optimal route of fetal delivery or the timing of neurosurgical resection of an arteriovenous malformation in the parturient. Anesthetic management is predicated on the principles of minimizing the cardiovascular changes of labor and preventing involuntary Valsalva maneuvers during the second stage of labor. Both of these goals are readily accomplished with epidural anesthesia.

Radioimmunotherapy strategies for non-Hodgkin's lymphomas

Radioimmunotherapy offers an exciting new therapeutic modality for patients with relapsed non-Hodgkin's lymphoma; however, considerable debate exists regarding the optimal dose and administration schedule for radioimmunoconjugates. Myelosuppression has been the dose-limiting toxicity of most clinical trials employing radiolabeled antibodies, and this complication has generated both high-dose and low-dose treatment strategies. 'Low-dose' strategies are nonmyeloablative and rely upon repetitive infusions to effectively eradicate tumor masses. Trials incorporating low-dose radioimmunotherapy have documented high response rates, though the durability of these responses remains unclear. The most encouraging nonmyeloablative studies have documented objective responses in 70%-80% of patients, complete responses in 30%-50% of patients, minimal toxicity, and a median response duration of 12 months. In contrast, high-dose trials performed in conjunction with autologous hematopoietic stem cell transplantation have demonstrated objective responses in 95% of patients, complete responses in 85% of patients, with a progression-free survival of 62% and an overall survival of 93% with a median follow-up of two years. Toxicities are considerably higher than those reported with nonmyeloablative regimens, but are modest compared to conventional marrow transplant conditioning regimens incorporating total body irradiation (TBI). Ongoing trials integrating high-dose radioimmuotherapy with high-dose chemotherapy in an autologous transplantation setting are testing the hypothesis that targeted radiotherapy plus chemotherapy will provide increased efficacy and diminished toxicity as compared to nonspecific external beam TBI-containing regimens.

Assessment of lower urinary tract symptoms in women by a self-administered questionnaire: test-retest reliability

A self-administered questionnaire assessing female lower urinary tract symptoms and their impact on quality of life is described and validated, on 56 females in six participating departments. The patients answered two identical questionnaires on separate occasions before treatment. Test-retest reliability of the questionnaire, correlation between the symptoms and their troublesomeness, and the reproducibility of this correlation were assessed. The percentage of mistakes in answers to each of the questions varied from 1.8% to 49.1%, mainly owing to missing answers in the item groups: appliances, sexual function and social activities. Test-retest showed a repeat frequency of 50.0%-91.0% for symptoms and 44.6%-82.1% for trouble. A highly significant positive correlation was found between symptoms and trouble, which was most pronounced for questions concerning pain and incontinence. This correlation was consistent within time. The primary validation of this questionnaire is good. Its relevance as a basis for medical priority and clinical decision making remains to be investigated.

Ophthalmoscopy for congenital hypertrophy of the retinal pigment epithelium (CHRPE) in patients with sporadic colorectal carcinoma

In order to investigate the frequency of congenital hypertrophy of the retinal pigment epithelium (CHRPE) in sporadic colorectal cancer, ophthalmoscopy was carried out in 34 patients with colorectal carcinoma without known familial disposition. CHRPE is one of the most frequent extracolonic manifestations in familial adenomatous polyposis. None of the patients showed any sign of CHRPE. It is concluded that although genetic factors are presumably of importance in the development of sporadic colorectal cancer, CHRPE cannot be used as a marker for future risk of colorectal carcinoma except in polyposis families.

Treatment of newly diagnosed children and adolescents with acute myeloid leukemia: a Childrens Cancer Group study

PURPOSE

The objectives of this study were to determine if the addition of etoposide, thioguanine, and dexamethasone to daunorubicin and cytarabine (five-drug regimen) during induction would improve remission induction rates and survival of children with acute myeloid leukemia (AML) when compared with the standard regimen of cytarabine and daunorubicin (7 + 3) and whether allogeneic bone marrow transplantation (BMT) or intensive chemotherapy consolidation with or without maintenance would give a superior outcome.

PATIENTS AND METHODS

A total of 591 assessable children with AML entered Childrens Cancer Group (CCG) trial 213 between January 1986 and February 1989. The status of patients as of September 1, 1992 forms the basis of this report. The results were compared with previous AML studies.

RESULTS

The projected survival rate of all patients at 5 years is 39% (event-free survival [EFS] rate, 31%), which is superior to that of the prior CCG study (P = .01). The induction rate was 79% for 7 + 3 and 76% for the five-drug regimen (not significant). Comparisons of BMT to chemotherapy favored BMT, but these differences do not always reach statistical significance (eg, 5-year disease-free survival [DFS] rate, 46% v 38% [P = .06] with donor available and 54% v 37% [P = .002] if treated according to protocol intent). No benefit for maintenance therapy was found and, in some comparisons, it was inferior to discontinuation of therapy (5-year survival rate, 46% v 68%, P < .01).

CONCLUSION

The 5-year EFS rate of patients with AML is 31% and has improved. The five-drug induction regimen is no better than standard induction, BMT appears superior to chemotherapy, and maintenance therapy was not beneficial.

The establishment of an HNPCC register

Guidelines for the establishment of an HNPCC-register are presented. The aims of a register are discussed. Steps in identification of families and persons at risk are suggested, and possible sources of family and pedigree data are mentioned. The role of a register in surveillance, information of family members and medical colleagues, research and international collaboration are discussed.

Post therapy imaging in high dose I-131 radioimmunotherapy patients

The biodistribution of a trace-labeled I-131 antibody is used to predict the biodistribution of a high dose I-131 antibody for therapy. Internal radiation dose estimates derived from the trace-labeled antibody have been used to determine the I-131 doses in a phase I escalating dose therapy trial for hematologic malignancy. To confirm the hypothesis that the distribution of a trace- and high-dose labeled antibodies are similar, both trace (7-11 mCi, 259-407 MBq) and high-dose (100-800 mCi, 3700-29600 MBq) I-131 radiolabeled antibody infusion were imaged in 12 patients who were treated for leukemia or lymphoma. With specialized imaging techniques using lead attenuation sheets, clearance data from organs were obtained from serial gamma camera images. Biological clearance half times of I-131 from both trace and therapy level doses were in agreement. An exception was a patient who developed human antimouse antibody before therapy, and subsequently had rapid clearance of the therapy dose. The method was feasible, yielded reproducible results, and provided critical data for relating therapy toxicity to radiation absorbed dose estimates.

Retention of B-cell-specific monoclonal antibodies by human lymphoma cells

The rates of endocytosis, intracellular degradation, and cell-surface shedding of 125I-labeled monoclonal antibodies (MoAbs) HD-37 (anti-CD19), B1 (anti-CD20), MB-1 (anti-CD37), BC8 (anti-CD45), and DA4-4 (anti-mu) by B-lymphoma cells were compared by cellular radioimmunoassay, ultrastructural autoradiography, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and thin layer chromatography using biopsy specimens from 12 patients with non-Hodgkin's lymphomas. 125I-BC8 was stably retained on the surface of lymphoma cells without appreciable internalization or shedding, whereas 125I-DA4-4 underwent rapid endocytosis and degradation. 125I-B1 was not internalized or degraded by tumor cells, but rapidly dissociated from the cell surface in intact form. Moderate rates of endocytosis, intracellular metabolism, and cell-surface shedding were shown by 125I-HD37 and 125I-MB-1. The 3 patients with diffuse, small cleaved-cell lymphomas internalized and degraded antibodies more slowly than did patients with other histologic subtypes. These kinetic differences may be important in the selection of MoAbs for immunotoxin and radioimmunoconjugate therapy of B-cell malignancies.

Biochemical characterization of a unique canine myeloid antigen

In marrow transplantation, radioisotope-labeled monoclonal antibodies may provide a way to selectively deliver high doses of radiation to target tissues (marrow in the case of myeloid malignancies) without significant toxicity to other normal organs. This paper describes the production and characterization of a novel monoclonal antibody, DM5, that we have developed for use in an animal model of radiotherapy targeted to the marrow. DM5 recognizes three glycosylation variants, gp19,21,23DM5, of a polypeptide core that is expressed on canine cells of the myeloid lineage, but not on lymphoid cells. The antigen recognized by DM5 is not present on most progenitor cells as determined by CFU-GM assays of DM5 positive and negative cell populations.

Effects of propylthiouracil on the biodistribution of an iodine-131-labeled anti-myeloid antibody in normal dogs: dosimetry and clinical implications

Despite the use of near maximal doses of chemoradiotherapy, tumor recurrence remains the most frequent cause of treatment failure following marrow transplantation for leukemia. We have previously demonstrated that it is possible to selectively deliver radiation to the marrow space. In that study an initial short half-life of the radionuclide was observed. In this study we attempted to prolong the retention of the radioiodine in marrow through the use of propylthiouracil (PTU). When administered to normal dogs, PTU pretreatment resulted in improved marrow localization of 131I-labeled DM-5. There was no appreciable loss of activity from the marrow during the 2-4 hr postinjection time interval; a finding in contrast to the control animals where marrow activity declined a mean 45 +/- 0.5% over the same time period. Additionally, in contrast to controls, a rise in plasma trichloroacetic acid (TCA) nonprecipitable activity was not demonstrated in the PTU treated group during this 2-4 hr period. These results suggest that PTU's inhibition of deiodinases resulted in longer residence time of the radionuclide in its target tissue without adversely affecting distribution to non-target organs.

Specific marrow localization of an 131I-labeled anti-myeloid antibody in normal dogs: effects of a "cold" antibody pretreatment dose on marrow localization

Tumor recurrence and regimen-related toxicity remain major obstacles in the successful use of marrow transplantation as therapy for hematologic malignancies. By attaching radionuclides to monoclonal antibodies (MoAbs) targeted at myeloid-associated antigenic determinants, a more effective and directed delivery of therapy may be possible without increasing toxicity. We investigated the biodistribution over time of an anti-myeloid antibody (DM-5) labeled with trace amounts of 131I in normal dogs. This study demonstrates the ability to target marrow with a high degree of selectivity, achieving marrow/blood ratios of 25-30:1 with the greatest concentration in any other organ being a tissue/blood ratio of 1.4:1 for stomach at 48 h. A pretreatment dose of unlabeled antibody effectively reduced early hepatic uptake by 80%, resulting in improved marrow localization with an estimated 58.6% of the injected dose localized in marrow within 2 h following infusion, compared to 32.8% without pretreatment. The marrow concentration clearance curve for the radioimmunoconjugate revealed an initial short half-life (4.75 h), suggesting rapid internalization, digestion, and release of free iodine (dehalogenation). This view was supported by a corresponding rise in trichloroacetic acid-non-precipitable activity during this period. Methods aimed at decreasing dehalogenation may result in longer residence time of the radionuclide within the marrow space, resulting in more effective tumor cell kill. This approach may provide a way to improve upon the current results obtained with marrow transplantation as treatment for patients with leukemia and other hematologic malignancies.

Biologic characteristics and treatment of acute nonlymphocytic leukemia in children. Report of the ANLL Strategy Group of the Childrens Cancer Study Group

Today approximately 75 per cent of children with ANLL can be induced into a complete remission and approximately 40 per cent will have an event-free survival for more than 3 years, irrespective of whether they received a bone marrow transplantation or chemotherapy after induction. In order to achieve these results very intensive therapy is required. The morbidity and mortality of treatment are high. The length of therapy needed after induction of remission is not known. Whether or not maintenance therapy is required is perhaps related most directly to the intensity of the therapy employed. Similarly, the role of bone marrow transplantation in patients in first remission, treatment of CNS leukemia, and treatment of chloromas are controversial. There is general agreement that WBCs over 100,000, acute monoblastic leukemia in infants less than 2 years of age, and certain chromosomal abnormalities are associated with a poor prognosis. Although there has been a dramatic improvement in the treatment of ANLL over the past 15 years, stratification of therapy based on biologic parameters, and alteration of treatment based on the early responses to treatment may be required before further advances will be made.

Immunodiagnosis and immunotherapy of childhood malignancies

Recent advances in immunologic techniques have allowed the generation of monoclonal antibodies against antigens on tumor cells and their normal counterparts. Monoclonal antibodies useful for diagnosing and defining subtypes of acute leukemias and neuroblastoma have been prepared, although the prognostic significance of the subtypes defined by such antibodies remains to be determined. The usefulness of these reagents for therapeutic purposes either ex vivo, in association with autologous bone marrow transplantation, or in vivo, as carriers of cytotoxic agents, is currently under investigation.

Correlation of chromosome abnormalities with patient characteristics, histologic subtype, and induction success in children with acute nonlymphocytic leukemia

Cytogenetic analyses of bone marrow cells were performed in 195 children with acute nonlymphocytic leukemia (ANLL) at diagnosis, as part of Childrens Cancer Study Group Study No. 251. Ninety-six patients (49%) exhibited clonal abnormalities, including trisomy 8 in 18 patients, t(8;21) in 11, t(15;17) in seven, loss of a sex chromosome in seven, monosomy 7 in seven, and the Philadelphia chromosome in four. Clonal abnormalities were found significantly more often in younger patients. Furthermore, recurring cytogenetic abnormalities tended to correlate with specific ages. For example, t(8;21) was associated significantly with children over four years of age, while -7 associated with overall loss of genetic material from the long arm of chromosome 7 (7q) and 11q- were associated significantly with younger children. Recurring chromosome abnormalities also correlated with specific ANLL histologic subtypes, such as t(8;21) with acute myelogenous leukemia and t(15;17) with acute promyelocytic leukemia. Presence or absence of cytogenetic abnormalities was compared with the ability of patients to achieve remission. Individuals exhibiting clonal abnormalities in bone marrow cells had an equally likely chance of achieving remission (74%) as those individuals with normal karyotypes (75%). Nonrandom chromosome abnormalities associated with a high induction success rate included +8 with a 94% induction success rate (P = .13) and t(8;21) with a 91% success rate (P = .46). Patients exhibiting the -7 abnormality associated with overall loss of 7q had a significantly less successful induction outcome, with only 28% achieving remission (P = .02); three of seven patients with t(15;17) died during induction therapy.

Current status of the biology and treatment of acute non-lymphocytic leukemia in children (report from the ANLL strategy group of the Children's Cancer Study Group

Major advances have been made in the past 10 yr in both the understanding of the biologic characteristics of acute nonlymphocytic leukemia and in the treatment of patients with this disease. Advances in the biologic characteristics include: a better understanding of the nature of leukemic cell proliferation and differentiation; a clearer description of the morphological, histochemical, and ultrastructural characteristics of leukemic cells; a recognition that a high percentage of patients may have specific cytogenetic abnormalities; and a recognition that biochemical differences exist between acute nonlymphocytic leukemia (ANLL) and acute lymphoblastic leukemia (ALL). Today, over 70% of children with ANLL can be induced into a complete remission and over 25% are remaining in a continuous remission for over 2 yr. In spite of these improved results, the best method of extending remissions is unknown. It is unlikely that better results of therapy will be achieved in the future by tailoring the treatment according to the biologic characteristics of the patient, since it appears that ANLL is a heterogeneous group of diseases.