Trajectory of functional outcome and health status after moderate-to-major trauma in Hong Kong: A prospective 5 year cohort study

BACKGROUND

Trauma care systems in Asia have been developing in recent years, but there has been little long-term outcome data from injured survivors. This study aims to evaluate the trajectory of functional outcome and health status up to five years after moderate to major trauma in Hong Kong.

METHODS

We report the five year follow up results of a multicentre, prospective cohort from the trauma registries of three regional trauma centres in Hong Kong. The original cohort recruited 400 adult trauma patients with ISS ≥ 9. Telephone follow up was conducted longitudinally at seven time points, and the extended Glasgow Outcome Scale (GOSE) and Short-Form 36 (SF36) were tracked.

RESULTS

119 out of 309 surviving patients (39%) completed follow up after 5 years. The trajectory of GOSE, PCS and MCS showed gradual improvements over the seven time points. 56/119 (47.1%) patients reported a GOSE = 8 (upper good recovery), and the mean PCS and MCS was 47.8 (95% CI 45.8, 49.9) and 55.8 (95% CI 54.1, 57.5) respectively at five years. Univariate logistic regression showed change in PCS - baseline to 1 year and 1 year to 2 years, and change in MCS - baseline to 1 year were associated with GOSE = 8 at 5 years. Linear mixed effects model showed differences in PCS and MCS were greatest between 1-month and 6-month follow up.

CONCLUSIONS

After injury, the most rapid improvement in PCS and MCS occurred in the first six to 12 months, but further recovery was still evident for MCS in patients aged under 65 years for up to five years.

The Epidemiology of Patients with Dizziness in an Emergency Department

Objectives

The aims of this prospective study were (1) to describe the patterns of presentation, causes and disposition of patients with dizziness in an emergency department (ED) and (2) to identify the factors that predict central vestibular disorder.

Methods

All adult patients (≥18 years) attending our ED with a chief complaint of dizziness were included. Demographic characteristics, presenting complaint, symptoms, past medical illnesses, physical findings, provisional diagnosis and disposition were recorded in a data collection sheet by the medical officers.

Results

A total of 104 consecutive dizzy patients were recruited from 12th to 19th December 2003. The incidence of adult patients with dizziness was 4.0% (104/2594). There were 34 (32.7%) male and 70 (67.3%) female patients; 64 (61.5%) patients were below 65 and 40 (38.5%) were above 65. Lightheadedness (61.5%), vertigo (31.7%) and disequilibrium (4.8%) were the most frequent complaints. Nausea and/or vomiting (32.7%) and raised blood pressure on arrival (23.1%) were the most common associated symptoms and physical finding respectively. Hypertension (38.5%) was the most common pre-existing medical illness. Of all patients, 63.5% had non-vestibular disorder, 31.7% had peripheral vestibular disorder and 4.8% had central vestibular disorder. A clinical diagnosis could be made in 52.9% of our dizzy patients and about 20 different diagnoses were made. The majority (82.7%) of the patients were discharged from the ED. A presenting complaint of lightheadedness, altered mental state, focal neurological signs, raised blood pressure and history of stroke were predictors of central vestibular disorder (p<0.05).

Conclusions

Lightheadedness and vertigo were the two commonest presentations of dizzy patients. Most dizzy patients had benign causes and could be discharged from the ED. Lightheadedness, focal neurological symptoms and signs, altered mental state, hypertension and previous stroke were factors that would help to diagnose central vestibular disorder.

Differences in Injury Pattern and Mortality between Hong Kong Elderly and Younger Patients

Background

The rapidly aging population in Hong Kong is causing an impact on our health care system. In Hong Kong, 16.5% of emergency department trauma patients are aged ≥65 years.

Objective

We aim to compare factors associated with trauma and differences in trauma mortality between elderly (≥65 years) and younger adult patients (15 to 64 years) in Hong Kong.

Methods

A retrospective observational study was performed using trauma registry data from the Prince of Wales Hospital, a 1200–bed acute hospital which is a regional trauma centre.

Results

A total of 2172 patients (331 [15.2%] elderly and 1841 [84.8%] younger) were included. Male patients predominated in the younger adult group but not in the elderly group. Compared with younger patients, elderly patients had more low falls and pedestrian-vehicle crashes and sustained injuries to the head, neck and extremities more frequently. The odds ratio (OR) for death following trauma was 5.5 in the elderly group (95% confidence interval [CI] 3.4–8.9, p>0.0001). Mortality rates increased progressively with age (p>0.0001) and were higher in the elderly at all levels of Injury Severity Score (ISS). Age ≥65 years independently predicted mortality (OR=5.7, 95% CI 3.5–9.3, p>0.0001). The elderly had a higher co-morbidity rate (58.6% vs. 14.1%; p>0.01). There was a lower proportion of trauma call activations for the elderly group (38.6% vs. 53.3%; p>0.01).

Conclusion

Elderly trauma patients differ from younger adult trauma patients in injury patterns, modes of presentation of significant injuries and mortality rates. In particular, the high mortality of elderly trauma requires renewed prevention efforts and aggressive trauma care to maximise the chance of survival.

Management of Suspected Deep Venous Thrombosis in an Emergency Medicine Ward in Hong Kong

Introduction

Clinical signs and symptoms can vary for patients with deep venous thrombosis (DVT). DVT is an important diagnosis to recognise as it can lead to proximal embolism into the pulmonary circulation resulting in sudden collapse and death. The objective of this study is to describe the management of patients with suspected DVT in the emergency medicine ward (EMW) setting in Hong Kong using a standardised clinical pathway.

Methods

A retrospective review was conducted for patients with suspected DVT admitted to the EMW from April to December 2008 using a standardised protocol. The use of a clinical prediction rule and diagnostic tests (including the modified Well's score, D-dimer and ultrasound examination) and outcomes (including the length of stay and secondary admission rate) were investigated.

Results

A total of 100 patients with suspected DVT were admitted to the EMW in the nine-month study period. DVT was confirmed in 30% using ultrasonography. Fifty-two percent of patients were in the high-risk category according to the modified Well's score. Seventy-six percent of patients had positive D-dimer results. Ten percent of patients were safely discharged without an ultrasound examination. Mean length of stay in the EMW was 1.99 days. Thirteen percent of patients required second admission to other specialties.

Conclusions

This study suggests that a standardised clinical pathway based in the EMW can be used for patients with suspected DVT to reduce hospital admission.

Acute myeloid leukemia targets for bispecific antibodies

Despite substantial gains in our understanding of the genomics of acute myelogenous leukemia (AML), patient survival remains unsatisfactory especially among the older age group. T cell-based therapy of lymphoblastic leukemia is rapidly advancing; however, its application in AML is still lagging behind. Bispecific antibodies can redirect polyclonal effector cells to engage chosen targets on leukemia blasts. When the effector cells are natural-killer cells, both antibody-dependent and antibody-independent mechanisms could be exploited. When the effectors are T cells, direct tumor cytotoxicity can be engaged followed by a potential vaccination effect. In this review, we summarize the AML-associated tumor targets and the bispecific antibodies that have been studied. The potentials and limitations of each of these systems will be discussed.

Strategies and solutions to alleviate access block and overcrowding in emergency departments

OBJECTIVES

Access block refers to the delay caused for patients in gaining access to in-patient beds after being admitted. It is almost always associated with emergency department overcrowding. This study aimed to identify evidence-based strategies that can be followed in emergency departments and hospital settings to alleviate the problem of access block and emergency department overcrowding; and to explore the applicability of these solutions in Hong Kong.

DATA SOURCES

A systematic literature review was performed by searching the following databases: CINAHL, Cochrane Database of Systematic Reviews, EMBASE, MEDLINE (OVID), NHS Evidence, Scopus, and PubMed.

STUDY SELECTION

The search terms used were "emergency department, access block, overcrowding". The inclusion criteria were full-text articles, studies, economic evaluations, reviews, editorials, and commentaries. The exclusion criteria were studies not based in the emergency departments or hospitals, and abstracts.

DATA EXTRACTION

Abstracts of identified papers were screened, and papers were selected if they contained facts, data, or scientific evidence related to interventions that aimed at improving outcome measures for emergency department overcrowding and/or access block. Papers identified were used to locate further references.

DATA SYNTHESIS

All relevant scientific studies were evaluated for strengths and weaknesses using appraisal tools developed by the Critical Appraisal Skills Programme. We identified solutions broadly classified into the following categories: (1) strategies addressing emergency department overcrowding: co-locating primary care within the emergency department, and fast-track and emergency nurse practitioners; and (2) strategies addressing access block: holding units, early discharge and patient flow, and political action--management and resource priority.

CONCLUSION

Several evidence-based approaches have been identified from the literature and effective strategies to overcome the problem of access block and overcrowding of emergency departments may be formulated.

Prolonged progression-free survival after consolidating second or later remissions of neuroblastoma with Anti-GD2 immunotherapy and isotretinoin: a prospective Phase II study

Relapse of high-risk neuroblastoma (HR-NB) is deemed invariably fatal yet increasing numbers of HR-NB patients achieve a second complete/very good partial remission (CR/VGPR), hence the urgency to find a successful consolidative therapy. Identifying efficacy in patients without assessable disease, however, is problematic. We report the first study providing outcome data for this group of patients with poor prognosis. To prevent another relapse, HR-NB patients in second or later CR/VGPR received the anti-G_D2 murine antibody 3F8 plus granulocyte-macrophage colony-stimulating factor plus isotretinoin in a Phase II trial. Upon meeting the target aim for progression-free survival (PFS) in the initial cohort of 33 patients, the trial was amended to allow patients who developed human anti-mouse antibody (HAMA) to receive rituximab to ablate HAMA with or without low-dose maintenance chemotherapy until immunotherapy could resume. For the total of 101 study patients, 5-year PFS and overall survival (OS) rates were 33% ± 5% and 48% ± 5%, respectively. Among the 33 long-term progression-free survivors, 19 had MYCN amplification, 19 had previously received anti-G_D2 immunotherapy plus isotretinoin (as first-line therapy), and 15 never received maintenance chemotherapy. In a multivariate analysis of prognostic factors, only absence of minimal residual disease in bone marrow after 2 cycles of immunotherapy and before initiation of isotretinoin or anti-HAMA therapy was significantly favorable for both PFS and OS. Therefore, long-term PFS is possible for HR-NB patients who achieve at least a second CR/VGPR and receive consolidation that includes anti-G_D2 immunotherapy plus isotretinoin, even if the patients received these biological treatments before relapse. Results from this prospective study will aid in the development of future Phase II studies for this growing ultra high-risk patient population.

Human derived dimerization tag enhances tumor killing potency of a T-cell engaging bispecific antibody

Bispecific antibodies (BsAbs) have proven highly efficient T cell recruiters for cancer immunotherapy by virtue of one tumor antigen-reactive single chain variable fragment (scFv) and another that binds CD3. In order to enhance the antitumor potency of these tandem scFv BsAbs (tsc-BsAbs), we exploited the dimerization domain of the human transcription factor HNF1α to enhance the avidity of a tsc-BsAb to the tumor antigen disialoganglioside GD2 while maintaining functional monovalency to CD3 to limit potential toxicity. The dimeric tsc-BsAb showed increased avidity to GD2, enhanced T cell mediated killing of neuroblastoma and melanoma cell lines in vitro (32–37 fold), exhibited a near 4-fold improvement in serum half-life, and enhanced tumor ablation in mouse xenograft models. We propose that the use of this HNF1α-derived dimerization tag may be a novel and effective strategy to increase the potency of T-cell engaging antibodies for clinical cancer immunotherapy.

Open-access colonoscopy: outcomes of referrals from the emergency department

AIM

The study investigated the diagnostic outcome of colonoscopy referrals from the emergency department (ED) via an open-access system.

METHOD

A retrospective cohort study over two years was performed on all patients under 65 years referred for open-access colonoscopy by the ED in a hospital with an annual ED attendance of 140,000. Patient characteristics and presenting symptoms were retrieved. Waiting times from presentation to colonoscopy were recorded.

RESULTS

Over a 2-year period, 266 patients were referred, of whom 37 defaulted, leaving 229 patients who had a colonoscopy. The mean age was 48.3 ± 11.3 (SD) and the female/male ratio was 229/125. The most frequent presenting symptoms included: rectal bleeding (n = 142, 62%), change of bowel habit (n = 47, 20.5%) and abdominal pain (n = 40, 17.5%). The median waiting time from presentation to colonoscopy was 17 (range 1-69) days. A positive colonoscopic finding was recorded in 45.4%, including colorectal cancer in 12 (5.2%).

CONCLUSION

The rate of a positive diagnoses from the ED-based colonoscopy referral service was comparable to that of the general Hong Kong population. This approach may help to reduce the waiting time for colonoscopy in a specialist colorectal clinic.

Bicycle related injuries presenting to a trauma centre in Hong Kong

BACKGROUND

Bicycle riding is a popular leisure activity and an important means of transportation in Hong Kong. Young cyclists' riding behaviour causes injury patterns which may differ from older riders. The aim of this study is firstly to describe bicycle related injuries presenting to a regional trauma centre in Hong Kong, and secondly to compare patients aged > 15 years with those patients aged < or = 15 years.

METHODS

This retrospective observational study examined all bicycle related injury patients presenting to the ED of the Prince of Wales Hospital (PWH) in 2006.

RESULTS

Results showed that bicycle helmet use was low in Hong Kong suggesting that the wearing of helmets when cycling should be promoted. Bicycle related injuries were common in children but the injuries in adults were more serious. Head and limb injuries were common and limbs on the left side were 2.5 times more likely to be injured than those on the right. The older group were more likely to be involved in a motor vehicle collision and sustained more severe injuries than the younger group. They had more serious head and neck, face, thorax and abdominal injuries compared to the younger group.

CONCLUSION

Prevention strategies should include more widespread helmet use and increasing bicycle lane provision to enable traffic separation in Hong Kong. The three 'E' approaches (education, enforcement and environment) should be implemented to prevent bicycle injuries in Hong Kong.

High risk trauma in older adults in Hong Kong: a multicentre study

BACKGROUND

Trauma is the eighth leading cause of death in Hong Kong. In 2002, 18.5% of the population of Hong Kong was aged 55 years or above, which increased to 22.1% in 2006. The increasing older population in Hong Kong presents a challenge to the health care system yet there is little local data on older trauma patients. The objectives of this study are firstly to describe the epidemiology of high risk trauma in older patients in Hong Kong, and secondly to identify predictors of trauma mortality.

METHOD

Retrospective analysis of prospectively collected data from a centralised trauma database; data collected from 2002 to 2004 from four trauma centres in Hong Kong.

RESULTS

Between 2002 and 2004, the four trauma centres had a total of 2,124,175 emergency department attendances of which 376,021 (17.7%) were trauma patients, and 80,827 (3.8%) were aged 55 years or older. 810 injured older patients met the inclusion criteria for this study. 380 (46.9%) patients had co-morbidity at the time of injury. Common causes of injury were falls (50.0%, 405/810) and motor vehicle crashes (33.6%, 272/810) of which (77.2%, 210/272) were pedestrians. Mortality was 24.4% (198/810) and increased with advancing age (p<0.0001). 53.5% (433/810) of patients had major trauma (ISS>15). Head injury contributed to 80.3% (159/198) of deaths. 38.4% (311/810) of patients required operations. Most patients were discharged home (40.5%, 328/810) and one-third (270/810) required rehabilitation. Significant predictors of mortality included co-morbidity, injury severity score, age and decreasing Glasgow Coma Score.

CONCLUSION

Pedestrians struck by motor vehicles and falls are the principal causes of trauma in older patients in Hong Kong. Mortality increased with advancing age. The independent indicators of trauma mortality in older patients are co-morbidity, age, ISS and GCS.

Long-term complications of neuroblastoma: A report from the Childhood Cancer Survivor Study

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Background: Neuroblastoma (NB) survivors can develop many complications from their treatment. We evaluated long-term morbidity and mortality in a large cohort of NB survivors. Procedures: Late effects data from 5-year NB survivors diagnosed between 1970–1986 enrolled in the Childhood Cancer Survivor Study (CCSS) were collected from self-administered questionnaires. 832 survivors and 3,899 siblings were included. Treatment data were abstracted from the medical records of all survivors. Late mortality, second malignant neoplasm (SMN), and chronic health conditions were analyzed in relation to treatment factors. Results: 42 survivors (6%) died more than 5 years after their diagnosis (standardized mortality ratio [SMR]:4.8; 95% CI 3.5–6.5). Causes of death included: disease recurrence (n=23), SMN (n=6) (SMR: 8.5; 95% CI 3.1–18.4), cardiac (n=1) (SMR 2.9; 95% CI 0.04–16.0), pulmonary (n=1) (SMR 4.8; 95% CI 0.1–26.5), external causes (n=4), other and unknown (n=11). 33 developed a SMN (standardized incidence ratio [SIR] 8.6; 95% CI 5.9–12.1): thyroid (n=7), renal (n=6), soft tissue sarcomas (n=3), acute myeloid leukemia (n=2), breast cancer (n=2) and other (n=13). Exposure to radiation therapy (RT) (p=0.003) and to VP-16 (p=0.04) were significant risk factors for SMN. 38% of the survivors reported at least one chronic health condition. Compared to siblings, they were more likely to report any chronic condition (risk ratio [RR] 14.7; 95% CI, 12.4–17.6). The most common prevalent conditions included: musculoskeletal (RR 49.8; 95% CI, 27.9–88.8), endocrine (RR 36.2; 95%CI 24.1–54.5), sensory (RR 21.5; 95%CI, 14.6–31.7) and neurological (RR 13.1; 95% CI 10.8–16). A multivariable Poisson regression analysis revealed the following associations: laminectomy (RR 8.6; 95% CI 3.5- 21) and chest RT (RR 2.8; 95% CI 1.3–6.5) as risk factors for scoliosis; age < 1 year at diagnosis (RR 1.9; 95% CI 1.4–2.6) and laminectomy (RR 3.5; 95% CI 2.4–5.3) for neurological complications; for hearing loss, increasing cumulative dose of cisplatin (for ≥ 600 mg/m2 RR 52.8; 95% CI 10.2–272.5); and RT to the neck (RR 6.6; 95% CI 2.4–18) for hypothyroidism. Conclusions: NB survivors are at risk of developing chronic conditions. Long-term surveillance is required for early detection of these complications.

No significant financial relationships to disclose.

Do trauma teams make a difference?

OBJECTIVE

To evaluate the association between trauma team activation according to well-established protocols and patient survival.

METHODS

Single centre, registry study of data collected prospectively from trauma patients (who were treated in a trauma resuscitation room, who died or who were admitted to ICU) of a tertiary referral trauma centre Emergency Department (ED) in Hong Kong. A 10-point protocol was used to activate rapid trauma team response to the ED. The main outcome measures were mortality, need for ICU care, or operation within 6h of injury.

RESULTS

Between 1 January 2001 and 31 December 2005, 2539 consecutive trauma patients were included in our trauma registry, of which 674 patients (mean age 43 years, S.D. 22; 71% male; 94% blunt trauma) met trauma call criteria. Four hundred and eighty two (72%) correctly triggered a trauma call, and 192 (28%) were not called ('undercall'). Patients were less likely to have a trauma call despite meeting criteria if they were aged over 64 years, had sustained a fall, had a respiratory rate <10 or >29 per minute, a systolic blood pressure between 60 and 89 mm Hg, or a GCS of 9-13. In a sub-group of moderately poor probability of survival (probability of survival, P(s), 0.5-0.75), the odds ratio for mortality in the undercall group compared with the trauma call group was 7.6 (95% CI, 1.1-33.0).

CONCLUSIONS

In our institution, undercalls account for 28% of patients who meet trauma call criteria and in patients with moderately poor probability of survival undercall is associated with decreased survival. Although trauma team activation does not guarantee better survival, better compliance with trauma team activation protocols optimises processes of care and may translate into improved survival.

Primary Trauma Diversion: Initial Experience in Hong Kong

BACKGROUND

Trauma is a leading cause of death and loss of workdays in Hong Kong. Reports have suggested that timely provision of care in dedicated trauma centers can improve outcomes. Until recently, ambulances were required to take trauma patients to the nearest hospital's emergency department. This paper reports on the initial experience of primary trauma diversion from scene to a dedicated trauma center in Hong Kong.

METHODS

This prospective study involved the establishment of primary trauma diversion in the area served by Alice Ho Nethersole Hospital (AHNH), a general hospital in the New Territories. Trauma patients who fulfilled diversion criteria were taken directly to the Prince of Wales Hospital (PWH) in Shatin, a university teaching hospital and trauma center for the area. Data were collected to determine the change in time to definitive care for trauma patients and an impact analysis on PWH services was performed.

RESULTS

There were 60 patients who underwent primary trauma diversion and 35 patients underwent secondary diversion after initial treatment at AHNH. This represented two extra trauma patients per week at PWH. Median Injury Severity Score (ISS) was 9 and 52% of patients had been involved in a traffic crash. Of eligible patients, 76% (69 out of 91) diverted correctly according to protocol. Primary trauma diversion patients reached definitive care 97 minutes faster than patients undergoing secondary diversion.

CONCLUSION

Primary trauma diversion is feasible in Hong Kong and means that patients reach definitive care 97 minutes faster than going to the nearest hospital. Primary trauma diversion protocols should be extended throughout Hong Kong.

Reduced time on the spinal board-effects of guidelines and education for emergency department staff

AIM

Prehospital spinal immobilisation is usually accomplished with a spinal board. Prolonged immobilisation on spinal boards in the emergency department (ED) can be detrimental. This study aimed to reduce the time spent by patients on spinal boards using a staff education program.

METHODS

Observational study in a trauma centre ED seeing 180,000ED attendances per year. The length of time immobilised on spinal board was recorded by the trauma nurse coordinator. Guidelines on removal of spinal boards were issued after recording period 1 (January-June 2001) and reinforced several times. The post-training period (period 2) extended from May to October 2003. Medians were compared using Mann-Whitney U-test (non-parametric data); chi-square test was used for categorical data.

RESULTS

There were 122 eligible patients in period 1 and 104 eligible patients in period 2. Median time to removal from the spinal board was reduced by 18.5 min from 50 to 31.5 min (Mann-Whitney U-test, p<0.0001, 95% CI for difference in medians 13-29 min). In period 1, 44 of 122 patients (36%) were removed from the spinal board before leaving the ED, compared to 78 of 104 patients (75%) in period 2 (p<0.0001, chi-square test).

CONCLUSION

The introduction of guidelines, reinforced by ED staff education, can significantly reduce the time patients spend on spinal boards after trauma and can increase the proportion of patients who can be removed from the board before leaving the ED.

Antibody-based diagnostic and therapeutic innovations for human cancer

As adjuvants, antibody-based diagnostic and therapeutic innovations can potentially decrease morbidity and mortality associated with many human malignancies. Current strategies employing genetically modified constructs may improve tumor penetration and increase versatility.

Phase II trial of the anti-G(D2) monoclonal antibody 3F8 and granulocyte-macrophage colony-stimulating factor for neuroblastoma

PURPOSE

To describe oncolytic effects of treatment with anti-G(D2) monoclonal antibody 3F8 plus granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with neuroblastoma (NB).

PATIENTS AND METHODS

Patients were eligible for 3F8/GM-CSF if intensive therapy had not eradicated potentially lethal NB. One cycle consisted of GM-CSF (subcutaneous bolus) on days 1 through 5, 11, and 12, and GM-CSF (2-hour intravenous [IV] infusion) followed after a 1-hour interval by 3F8 (1.5-hour IV infusion) on days 6 through 10 and 13 through 17. GM-CSF was dosed at 250 microg/m(2)/d on days 1 through 7 and at 500 microg/m(2)/d on days 8 through 17. 3F8 was dosed at 10 mg/m(2)/d (100 mg/m(2)/cycle). 3F8 was given with an opiate and an antihistamine. Patients without progressive disease (PD) or elevated human antimouse antibody titers could be treated again beginning 3 weeks after completion of a cycle.

RESULTS

Among 19 patients treated for NB resistant to induction therapy, 12 of 15 had complete remission (CR) of bone marrow (BM) disease, and three others who had less than partial responses achieved prolonged progression-free survival (one remains on study at 21+ months, two had PD at 12 and 17 months). Among patients treated for recurrent NB resistant to retrieval therapy, five of 10 had CR in BM. The 15 patients treated for PD fared poorly, although two had scintigraphic findings suggestive of a short-term response. Side effects were limited to readily manageable pain and, less commonly, rash of short duration; hence, patients were treated as outpatients.

CONCLUSION

3F8/GM-CSF is well tolerated and shows promise for treatment of minimal residual NB in BM.

Monoclonal antibody-based therapy of neuroblastoma

The curative potential of mAbs in the treatment of patients with metastatic neuroblastoma is increasingly evident. The idiotype network appears to represent one component of a complex mechanism for success with mAb-based immunotherapy. Ongoing strategies to modify or reconstruct mAbs, to engage them with cytokines, or to unite them with T cells open new avenues for harnessing the unique forces of the immune system against some of the most deadly pediatric cancers.

Neuroblastic and Schwannian stromal cells of neuroblastoma are derived from a tumoral progenitor cell

The coexistence of neuroblastic and Schwannian stromal (SS) cells in differentiating neuroblastoma (NB), and derivation of Schwannian-like cells from neuroblastic clones in vitro, were accepted previously as evidence of a common pluripotent tumor stem line. This paradigm was challenged when SS cells were suggested to be reactive in nature. The advent of microdissection techniques, PCR-based allelic analysis, and in situ fluorescent cytometry made possible the analysis of pure cell populations in fresh surgical specimens, allowing unequivocal determination of clonal origins of various cell subtypes. To overcome the complexity and heterogeneity of three-dimensional tissue structure, we used: (a) Laser-Capture Microdissection to obtain histologically homogeneous cell subtype populations for allelotype analysis at chromosomes 1p36, 11q23, 14q32, and 17q and study of MYCN copy number; (b) multiparametric analysis by Laser-Scanning Cytometry of morphology, DNA content, and immunophenotype of intact cells from touch imprints; and (c) bicolor fluorescence in situ hybridization on touch imprints from manually microdissected neuroblast and stroma-rich areas. Histologically distinct SS and neuroblastic cells isolated by Laser-Capture Microdissection had the same genetic composition in 27 of 28 NB analyzed by allelic imbalance and gene copy number. In all 20 cases studied by Laser-Scanning Cytometry, SS cells identified by morphology and S-100 immunostaining had identical DNA content and GD2-staining pattern as their neuroblastic counterparts. In 7 cases, fluorescence in situ hybridization demonstrated the same chromosomal makeup for SS and neuroblastic cells. These results provide unequivocal evidence that neuroblastic and SS cells in NB are derived from genetically identical neoplastic cells and support the classical paradigm that NB arises from tumoral cells capable of development along multiple lineages.

Topotecan combined with myeloablative doses of thiotepa and carboplatin for neuroblastoma, brain tumors, and other poor-risk solid tumors in children and young adults

Topotecan appears to be relatively unaffected by the most common multidrug resistance mechanisms, may potentiate cytotoxicity of alkylators, has good penetration into the central nervous system, is active against a variety of neoplasms, and has myelosuppression as its paramount toxicity. We present our experience with a myeloablative regimen that includes topotecan. Twenty-one patients with poor-prognosis tumors and intact function of key organs received topotecan 2 mg/m2 by 30-min intravenous (i.v.) infusion on days -8, -7, -6, -5, -4; thiotepa 300 mg/m2 by 3 h i.v. infusion on days -8, -7, -6; and carboplatin by 4 h i.v. infusion on days -5, -4, -3 with a daily dose derived from the pediatric Calvert formula, using a targeted area under the curve of seven mg/ml* min ( approximately 500 mg/m2/day). Stem cell rescue was on day 0. The patients were 1 to 29 (median 4) years old; 18 were in complete remission (CR) and three in partial remission (PR). Early toxicities were severe mucositis and erythema with superficial peeling in all patients and a seizure, hypertension, and renal insufficiency followed by veno-occlusive disease in one patient each. Post-transplant treatment included radiotherapy alone (four patients) or plus biological agents (11 patients with neuroblastoma). With a follow-up of 6+ to 32+ (median 11+) months, event-free survivors include 10/11 neuroblastoma patients (first CR), 4/5 brain tumor patients (second PR or CR), 1/3 patients with metastatic Ewing's sarcoma (first or second CR), and a patient transplanted for multiply recurrent immature ovarian teratoma; a patient with desmoplastic small round-cell tumor (second PR) had progressive disease at 8 months. Favorable results for disease control, manageable toxicity, and the antitumor profiles of topotecan, thiotepa, and carboplatin, support use of this three-drug regimen in the treatment of neuroblastoma and brain tumors; applicability to other tumors is still uncertain.

Immunomagnetic purging of Ewing's sarcoma from blood and bone marrow: quantitation by real-time polymerase chain reaction

PURPOSE

A propensity for hematogenous spread with resulting contamination of autologous cell products complicates cellular therapies for Ewing's sarcoma. We used a new approach to purge artificially contaminated cellular specimens of Ewing's sarcoma and show the capacity for real-time polymerase chain reaction (PCR) to quantify the contamination level of Ewing's sarcoma in such specimens.

PATIENTS AND METHODS

Binding of monoclonal antibody (MoAb) 8H9 to Ewing's sarcoma cell lines and normal hematopoietic cells was studied using flow cytometry. Using real-time PCR--based amplification of t(11;22), levels of Ewing's contamination of experimental and clinical cellular products were monitored. Purging was accomplished using immunomagnetic-based depletion. Monitoring of the function of residual hematopoietic progenitors and T cells was performed using functional assays.

RESULTS

MoAb 8H9 shows binding to Ewing's sarcoma but spares normal hematopoietic tissues. Nested real-time PCR is capable of detecting contaminating Ewing's sarcoma cells with a sensitivity of one cell in 10(6) normal cells. After 8H9-based purging, a 2- to 3-log reduction in contaminating Ewing's sarcoma was shown by real-time PCR, with purging to PCR negativity at levels of contamination of 1:10(6). Levels of contamination in clinical samples ranged from 1:10(5) to 10(6). Therefore, 8H9-based purging of clinical samples is predicted to reduce tumor cell contamination to a level below the limit of detection of PCR.

CONCLUSION

These results demonstrate a new approach for purging contaminated cellular products of Ewing's sarcoma and demonstrate the capacity of real-time PCR to provide accurate quantitative estimates of circulating tumor burden in this disease.

GD2 synthase: a new molecular marker for detecting neuroblastoma

BACKGROUND

Neuroblastomas (NBs) almost ubiquitously express the ganglioside GD2. GD2 synthesis is dependent on the key enzyme GD2 synthase. Thus, GD2 synthase transcript may prove to be a potential molecular marker of NB.

METHODS

Seventy-seven NB tumor tissues of all stages, 5 NB cell lines, and 26 normal bone marrows (BMs) and peripheral blood (PBL) samples, as well as 26 non-NB remission-BMs were analyzed for the expression of GD2 synthase by a highly sensitive reverse transcriptase-polymerase chain reaction (RT-PCR) and chemiluminescence detection. One hundred fifty-two NB BMs were tested and comparisons were made among three independent detection techniques, namely GD2 synthase RT-PCR, immunofluorescence (IF), and histology (HIST).

RESULTS

GD2 synthase transcript was present in 5 of 5 cell lines and in 77 of 77 tumors tested. Among 116 marrows that were positive by at least 1 of the 3 methods, 78% were detectable by GD2 synthase, 68% by IF, and 46% by HIST. Seventy-six percent of positive BMs that were obtained during treatment and follow-up had GD2 synthase expression, whereas only 29% were HIST positive. Correlation between RT-PCR and IF was high (P = 0.001), and positivity by 3 out of 3 methods was strongly correlated with poor survival (P < 0.01). Of note, marrows tested at the time of chemotherapy were positive by at least 2 out of 3 methods and were associated with adverse outcome (P = 0.01). Serial samples (n = 28) in 5 patients demonstrated close agreement between RT-PCR and patient disease status.

CONCLUSIONS

The current study found that molecular detection of GD2 synthase transcript in NB BMs may have potential value in detecting rare tumor cells.

Molecular genetics of neuroblastoma and the implications for clinical management: a review of the MSKCC experience

Neuroblastoma (NB) is a biological, genetic, and morphological heterogeneous neoplasm and demonstrates diverse clinical behavior. There exist at least three clinical patterns of NB: A) spontaneously regressing widespread disease; B) not metastatic local-regional disease, and C) metastatic disease (stage 4), frequently with lethal consequences. Patients with non-stage 4 NB are expected to survive even without medical treatment whereas stage 4 patients have an overall survival rate of 20% despite multimodality therapy protocols. The clinical management of patients with NB is therefore challenged by the objective identification of cases in which noncytotoxic approaches can be safely taken. Experience in the last decade at Memorial Sloan-Kettering Cancer Center supports the hypothesis that the natural history of disease defines relevant clinical groups of NB and has distinct molecular genetic profiles allowing therapeutic approaches tailored for each group. Here we review the natural history and clinicobiological features of 113 NB cases managed uniformly in our institution in an attempt to characterize useful genetic markers to support the decision making of noncytotoxic versus cytotoxic approaches for each category of NB.

Extending positron emission tomography scan utility to high-risk neuroblastoma: fluorine-18 fluorodeoxyglucose positron emission tomography as sole imaging modality in follow-up of patients

PURPOSE

Although positron emission tomography (PET) with fluorine-18 fluorodeoxyglucose ((18)F-FDG) has a major impact on the treatment of adult cancer, the reported experience with extracranial tumors of childhood is limited. We describe a role for PET in patients with neuroblastoma (NB).

PATIENTS AND METHODS

In 51 patients with high-risk NB, 92 PET scans were part of a staging evaluation that included iodine-123 or iodine-131 metaiodobenzylguanidine (MIBG) scan, bone scan, computed tomography (and/or magnetic resonance imaging), urine catecholamine measurements, and bone marrow (BM) examinations. The minimum number of tests sufficient to detect NB was determined.

RESULTS

Of 40 patients who were not in complete remission, only 1 (2.5%) had NB that would have been missed had a staging evaluation been limited to PET and BM studies, and 13 (32.5%) had NB detected by PET but not by BM and urine tests. PET was equal or superior to MIBG scans for identifying NB in soft tissue and extracranial skeletal structures, for revealing small lesions, and for delineating the extent and localizing sites of disease. In 36 evaluations of 22 patients with NB in soft tissue, PET failed to identify only two long-standing MIBG-negative abdominal masses. PET and MIBG scans showed more skeletal lesions than bone scans, but the normally high physiologic brain uptake of FDG blocked PET visualization of cranial vault lesions. Similar to MIBG, FDG skeletal uptake was diffusely increased with extensive or progressing BM disease but faint or absent with minimal or nonprogressing BM disease.

CONCLUSION

In the absence or after resolution of cranial vault lesions, and once the primary tumor is resected, PET and BM tests suffice for monitoring NB patients at high risk for progressive disease in soft tissue and bone/BM.

Genetic heterogeneity and clonal evolution in neuroblastoma

Tumour heterogeneity and clonal evolution at the genetic level may explain the development of malignant or resistant disease during clinical progression of neuroblastoma (NB). In this report we use 1p allelic analysis and DNA ploidy to evaluate clonal heterogeneity and clonal selection in vivo. We studied a total of 69 tumours from 29 patients with NB. To evaluate tumour heterogeneity and clonal evolution in vivo we used a panel of polymorphic allelic markers mapping to chromosome 1. 33 tumours from 12 patients (group 1) were obtained from different sites during the same surgery or at sequential surgeries without intervening chemotherapy to evaluate genetic heterogeneity. Paired samples from 10 patients (group 2) were used to evaluate clonal selection before and after chemotherapy. In 6 cases paired tumours and derived cell lines were studied. Analysis of DNA ploidy changes by karyotype, FISH and flow cytometry was performed in 15 tumours from 6 multiply recurred local-regional (LR) NB patients. Allelotype study revealed that 66% (8/12) of group 1 samples were heterogeneous, with distinct allelic patterns in tumour samples separated by time or location. In group 2 allelic patterns were different in post-chemotherapy specimens in 60% (6/10). DNA ploidy analysis showed that pre-chemotherapy samples contained 2 distinct ploidy clones, one diploid and one triploid, whereas all post-chemotherapy tumor samples were 100% diploid. These findings suggest that NB exhibits a high degree of clonal heterogeneity and clonal evolution occurs during the course of therapy and clinical progression.

Quantitation of marrow disease in neuroblastoma by real-time reverse transcription-PCR

PURPOSE

GD2 is abundantly expressed in neuroblastoma (NB). GD2 synthesis is dependent on key enzyme beta 1,4-N-acetylgalactosaminyltransferase (GD2 synthase). We explore the potential of GD2 synthase mRNA as a molecular marker of minimal residual disease by first comparing it quantitatively with immunocytology and then testing its clinical utility.

EXPERIMENTAL DESIGN

A real-time reverse transcription-PCR assay to quantify mRNA of GD2 synthase was developed. Quantitation was normalized to endogenous control glyceraldehyde-3-phosphate dehydrogenase in a multiplex PCR.

RESULTS

The upper limit of normal was defined by 31 normal marrow and blood samples, achieving a sensitivity of one NB cell in 10(6) normal mononuclear cells. When 155 bone marrows from 100 NB patients were studied, GD2 synthase mRNA levels correlated well with the number of GD2-positive cells, as measured by immunocytology using anti-GD2 antibodies (r = 0.96). This is the first demonstration of the quantitative relationship between a specific mRNA and the actual number of tumor cells. In a pilot study, the level of this transcript in sequential marrow samples of five stage 4 NB patients correlated closely with their clinical status. At 24 months after diagnosis, available remission bone marrows from patients with advanced NB diagnosed at >1 year of age initially treated with protocols N6 and N7 at Memorial Sloan-Kettering Cancer Center (n = 44) were analyzed for GD2 synthase mRNA. Positivity was strongly associated with progression-free (P < 0.005) and overall survival (P < 0.001).

CONCLUSIONS

Measurement of tumor cells by real-time quantitative reverse transcription-PCR of GD2 synthase has potential clinical utility, especially for the detection of minimal residual disease.

Hyperfractionated low-dose radiotherapy for high-risk neuroblastoma after intensive chemotherapy and surgery

PURPOSE

To assess prognostic factors for local control in high-risk neuroblastoma patients treated with hyperfractionated 21-Gy total dose to consolidate remission achieved by dose-intensive chemotherapy and surgery.

PATIENTS AND METHODS

Patients with high-risk neuroblastoma in first remission received local radiotherapy (RT) totaling 21 Gy in twice-daily 1.5-Gy fractions. RT to the primary site followed dose-intensive chemotherapy and tumor resection; the target field encompassed the extent of tumor at diagnosis, plus 3-cm margins and regional lymph nodes. RT to distant sites followed radiologic evidence of response. Local failure was correlated with clinical factors (including other consolidative treatments) and biologic findings.

RESULTS

Of 99 consecutively irradiated patients followed for a median of 21.1 months from RT, 10 relapsed in or at margins of RT fields at 1 to 27 months (median, 14 months). At 36 months after RT, the probability of primary-site failure was 10.1% +/- 5.3%. No primary-site relapses occurred among the 23 patients whose tumors were excised at diagnosis, but there were three such relapses among the seven patients who were irradiated with evidence of residual disease in the primary site. Four of 18 patients with MYCN-amplified disease and serum lactate dehydrogenase greater than 1,500 U/L had local failures (23.4% +/- 10.7% risk at 18 months). Acute radiotoxicities were insignificant, but three of 35 patients followed for > or = 36 months had short stature from decreased growth of irradiated vertebra.

CONCLUSION

Hyperfractionated 21-Gy RT is well tolerated and, together with dose-intensive chemotherapy and surgery, may help in local control of high-risk neuroblastoma. Extending the RT field to definitively encompass regional nodal groups may improve results. Visible residual disease may warrant higher RT dosing. Patients with biologically unfavorable disease may be at increased risk for local failure. RT to the primary site may not be necessary when tumors are excised at diagnosis.

Monoclonal antibody 8H9 targets a novel cell surface antigen expressed by a wide spectrum of human solid tumors

Tumor-restricted surface antigens may be targets for diagnosis and immune-based therapies. Monoclonal antibody 8H9 is a murine IgG1 hybridoma derived from the fusion of mouse myeloma SP2/0 cells and splenic lymphocytes from BALB/c mice immunized with human neuroblastoma. By immunohistochemistry, 8H9 was highly reactive with human brain tumors, childhood sarcomas, and neuroblastomas, and less so with adenocarcinomas. Among primary brain tumors, 15 of 17 glioblastomas, 3 of 4 mixed gliomas, 4 of 11 oligodendrogliomas, 6 of 8 astrocytomas, 2 of 2 meningiomas, 3 of 3 schwannomas, 2 of 2 medulloblastomas, 1 of 1 neurofibroma, 1 of 2 neuronoglial tumors, 2 of 3 ependymomas, and 1 of 1 pineoblastoma tested positive. Among sarcomas, 21 of 21 Ewing's/primitive neuroectodermal tumor, 28 of 29 rhabdomyosarcomas, 28 of 29 osteosarcomas, 35 of 37 desmoplastic small round cell tumors, 2 of 3 synovial sarcomas, 4 of 4 leiomyosarcomas, 1 of 1 malignant fibrous histiocytoma, and 2 of 2 undifferentiated sarcomas tested positive with 8H9. Eighty-seven of 90 neuroblastomas, 12 of 16 melanomas, 3 of 4 hepatoblastomas, 7 of 8 Wilms' tumors, 3 of 3 rhabdoid tumors, and 12 of 27 adenocarcinomas also tested positive. In contrast, 8H9 was nonreactive with normal human tissues including bone marrow, colon, stomach, heart, lung, muscle, thyroid, testes, pancreas, and human brain (frontal lobe, cerebellum, pons, and spinal cord). Reactivity with normal cynomolgus monkey tissue was restricted similarly. Indirect immunofluorescence localized the antigen recognized by 8H9 to the cell membrane. The antigen is proteinase sensitive and is not easily modulated off the cell surface. 8H9 immunoprecipitated a M(r) 58,000 band after N-glycanase treatment, most likely a protein with a heterogeneous degree of glycosylation. This novel antibody-antigen system may have potential for tumor targeting.

Loss of heterozygosity at 19q13.3 is associated with locally aggressive neuroblastoma

A genome-wide allelic analysis of neuroblastoma (NB) revealed a previously undescribed increased incidence of loss of heterozygosity (LOH) on chromosome arm 19q13 primarily affecting stages 3 and 4N disease. Further allelic analysis of chromosome 19q13 in a cohort of 116 NB patients using 17 polymorphic microsatellite markers identified the shortest common region of loss between D19S606 and D19S112 at 19q13.3. In some cases, clonal LOH at 19q13 was acquired during the course of disease, and deleted clones remained after cytotoxic therapy. In multivariant analysis, 19q13 LOH was associated with overall survival in local-regional International Neuroblastoma Staging System stages 1, 2, and 3 patients and was specifically present in tumors at the site of recurrence.

Neuroblastoma metastatic to the central nervous system. The Memorial Sloan-kettering Cancer Center Experience and A Literature Review

BACKGROUND

The central nervous system (CNS) can be a sanctuary site for cancer cells, because the blood-brain barrier impedes penetration of most chemotherapeutic agents. The authors hypothesized that, with improved survival from childhood metastatic neuroblastoma (NB), the incidence of CNS (intraparenchymal and leptomeningeal) spread may increase. They undertook this study to assess the frequency of CNS NB, to analyze risk factors and treatment options, and to review the literature.

METHODS

The authors retrospectively analyzed all patients with metastatic NB who were treated on protocols N4, N5, N6, and N7 from 1980 to 1999 at Memorial Sloan-Kettering Cancer Center (MSKCC), during which time there was an increase in the overall survival rate.

RESULTS

Two hundred fifty-one patients with Stage 4 NB (Group 251) were studied, of which 127 (Group 127) were newly diagnosed patients who were treated initially at MSKCC. None had CNS NB at the time of diagnosis. Eleven patients developed documented CNS disease; 8 of these 11 recurrences were isolated in the CNS. For Group 127, the overall incidence rate of CNS NB was 6.3%, with an increase in incidence from N4-N5 to N6-N7 of from 1.7% to 11.7%. Seven patients had isolated CNS disease recurrences. Only lumbar punctures (LP) performed near the time of diagnosis in patients with known bone marrow involvement were associated with subsequent development of CNS disease. For the entire group of 251 patients, lumbar puncture at the time of diagnosis and elevated serum lactic dehydrogenase levels were prognostic. Among the larger series reported in the literature, CNS involvement from metastatic lesions was rare at the time of diagnosis and remained an uncommon complication.

CONCLUSIONS

The incidence of CNS NB may be increasing. Because it is the sole site of disease recurrence in 64% of patients, the CNS may represent a sanctuary site for NB. CNS NB is associated with diagnostic lumbar punctures in patients with known bone marrow disease, raising the possibility that circulating or epidural microscopic tumor cells may seed the craniospinal axis.

Survival analysis of clinical, pathologic, and genetic features in neuroblastoma presenting as locoregional disease

BACKGROUND

Locoregional neuroblastoma is a clinical subgroup characterized by the absence of distant metastasis (International Neuroblastoma Staging System Stages 1, 2, and 3). Although these patients generally have an excellent survival with minimal therapy, some do experience recurrence with lethal consequences.

METHODS

To identify risk factors for disease progression, the authors performed a retrospective analysis of clinical (age and stage) and tumor biologic markers (histology, MYCN, DNA index, and allelic analysis of chromosomes 1p, 11q12-qter, and 14q12-q32) in 44 patients (10 Stage 1, 18 Stage 2, and 16 Stage 3). Allelic analysis was performed using polymorphic polymerase chain reaction markers in a semiautomated, fluorescent detection system.

RESULTS

Sixteen patients (38%) were younger than 365 days at diagnosis. Seventeen of 39 tumors (43%) had unfavorable histology, 6 (13%) were MYCN amplified, 14 (31%) were diploid, 17 (38%) had 1p36 loss of heterozygosity (LOH), 11 (25%) had 1p22 LOH, 10 (22%) had 11q LOH, and 13 (29%) had 14q LOH. Seventeen patients (38%) progressed, including 6 who progressed to Stage 4 disease (13%). Sixteen patients with progressive disease received cytotoxic therapy. Thirty-seven patients are alive (84%) with a median follow-up of 51 months. By permutation log rank test, both MYCN amplification and diploidy were associated with overall survival (OS), but only diploidy was associated with progression free survival (PFS) and progression to Stage 4 disease. LOH of 1p36, 1p22, 11q, or 14q did not show correlation with either OS or PFS.

CONCLUSIONS

Locoregional neuroblastoma tumors with diploid DNA index, regardless of other biologic features, have increased risk of local recurrence and Stage 4 progression.

Detection of microscopic disease: comparing histology, immunocytology, and RT-PCR of tyrosine hydroxylase, GAGE, and MAGE

BACKGROUND

We first explored the use of multiple molecular markers to overcome tumor heterogeneity. Sixty-seven neuroblastoma (NB) tumors were tested for the expression of GAGE, MAGE-2, MAGE-2, MAGE-3, and MAGE-4 by RT-PCR and then chemiluminescence; 82% of tumors had detectable GAGE, and 88% expressed at least one of the four MAGE genes.

PROCEDURE AND RESULTS

By combining GAGE and MAGE, 64 of 67 (95%) of tumors became detectable; 17 of 67 coexpressed all five molecular markers. Neither GAGE nor MAGE expression correlated with stage. GAGE was found to have the broadest (18 of 18) expression among stage 4 tumors. Two hundred fifty-nine bone marrows from 99 patients were then studied for NB positivity by four detection methods: histology, immunocytology, and molecular detection by GAGE and tyrosine hydroxylase (TH) mRNA. Two hundred seven samples were NB-positive by one detection method. All four techniques were comparable in detecting tumor cells at diagnosis and at relapse. GAGE and immunocytology were far more sensitive than histology and TH mRNA when marrows were sampled during chemotherapy and at the time of clinical remission.

CONCLUSIONS

By combining multiple molecular markers and independent screening techniques, we may be able to overcome tumor heterogeneity and expedite the detection of microscopic disease in the clinical management of neuroblastoma.

N7: a novel multi-modality therapy of high risk neuroblastoma (NB) in children diagnosed over 1 year of age

BACKGROUND

The N7 protocol for poor-risk neuroblastoma uses dose-intensive chemotherapy (as in N6 protocol [Kushner et al.: J Clin Oncol 12:2607-2613, 1994] but with lower dosing of vincristine) for induction, surgical resection and 2100 cGy hyperfractionated radiotherapy for local control, and for consolidation, targeted radioimmunotherapy with 131I-labeled anti-GD2 3F8 monoclonal antibody and immunotherapy with unlabeled/unmodified 3F8 (400 mg/m2).

PROCEDURE

The chemotherapy consists of: cyclophosphamide 70 mg/kg/d x 2 and a 72-hr infusion of doxorubicin 75 mg/m2 plus vincristine 2 mg/m2, for courses 1, 2, 4, and 6; and cisplatin 50 mg/m2/d x 4 and etoposide 200 mg/m2/d x 3, for courses 3, 5, and 7. 131I-3F8 is dosed at 20 mCi/kg, which is myeloablative and therefore necessitates stem-cell support.

RESULTS

Of the first 24 consecutive previously untreated patients more than 1 year old at diagnosis, 22 were stage 4 and two were unresectable stage 3 with MYCN amplification. Chemotherapy achieved CR/VGPR in 21 of 24 patients. Twenty patients to date have completed treatment with 131I-3F8, and 15 patients have completed all treatment. With a median follow-up of 19 months, 18 of 24 patients remain progression-free.

CONCLUSIONS

Major toxicities were grade 4 myelosuppression and mucositis during chemotherapy, and self-limited pain and urticaria during antibody treatment. Late effects include hearing deficits and hypothyroidism.

Disaloganglioside GD2 loss following monoclonal antibody therapy is rare in neuroblastoma

BACKGROUND

Gangliosicle GD2 is abundant on human neuroblastoma (NB). Monoclonal antibody 3F8 targeted to GD2 may have imaging and therapeutic potential. Antigen-negative clones can escape immune-mediated attack leading to clinical resistance or recurrence.

PROCEDURE

Among 95 evaluable patients treated intravenously with 3F8 (94 Stage 4, 1 Stage 3), 66 received nonradiolabeled 3F8, 11 received 131-iodine-labeled-3F8 (8-28 mCi/kg) with autologous bone marrow rescue, and 18 received both forms of treatment. Prior to treatment, 90 patients tested positive for GD2 reactivity by bone marrow immunofluorescence (n = 68), tumor immunohistochemistry (n = 20), or diagnostic radioimmunoscintigraphy (n = 2).

RESULTS

Of 62 patients who had refractory or recurrent neuroblastoma following 3F8 treatment, 61 (98%) tested positive for GD2 reactivity by bone marrow immunofluorescence (n = 51) or tumor immunohistochemistry (n = 10). The sole tumor that lost GD2 expression underwent phenotypic transformation into a pheochromocytoma-like tumor.

CONCLUSIONS

The persistence of GD2 expression in refractory or recurrent NB suggests that complete antigen loss is an uncommon event and cannot account for treatment failure.

Targeted radioimmunotherapy for leptomeningeal cancer using (131)I-3F8

BACKGROUND

Intrathecal antibody-based targeted therapies may have clinical potential for patients with leptomeningeal (LM) cancer.

PROCEDURE

Five patients with GD2-positive LM tumors were injected with 1-2 mCi intra-Ommaya (131)I-3F8, a murine IgG3 antibody specific for GD2. Serial cerebrospinal fluid (CSF) and serum samples and SPECT imagings (4, 24, and 48 hr) were performed to predict radiation doses to the tumor and normal brain and blood prior to the administration of larger therapeutic doses.

RESULTS

Side effects included self-limited fever, headache, and vomiting. Focal (131)I-3F8 uptake consistent with tumors was seen along the craniospinal axis in four patients. Calculated radiation dose to the CSF was 14.9-56 cGy/mCi and to blood and other organs outside the CNS less than 2 cGy/mCi.

CONCLUSIONS

Intraventricular (131)I-3F8 successfully detected LM disease and resulted in a large favorable CSF/blood ratio. Intraventricular (131)I-3F8 may have clinical utility in the diagnosis and radioimmunotherapy of GD2-positive LM cancers. Med. Pediatr. Oncol. 35:716-718. 2000.

Prognostic significance of GAGE detection in bone marrows on survival of patients with metastatic neuroblastoma

BACKGROUND

Previously, we reported the utility of GAGE as a molecular marker for neuroblastoma (NB) and malignant melanoma in blood and bone marrow (BM). Among patients with stage III melanoma rendered disease-free by surgery, GAGE expression was a strong prognostic factor for patient survival.

PROCEDURE

All patients with advanced NB diagnosed at > 1 year of age initially treated with protocol N6 (n = 24) and N7 (n = 38) at Memorial Sloan-Kettering Cancer Center were included in this study. Their BM cells at 12, 18, and 24 months (median time after diagnosis) were evaluated for the presence of GAGE.

RESULTS

GAGE positivity at 12 months (25%), when patients were still on treatment, did not predict progression-free survival (PFS) and overall survival from the time of sampling. Positivity at 18 months (29%) was associated with poorer PFS and survival (but P > 0.05). By 24 months, the presence of GAGE (26%) was a very strong predictor of out-come (P < 0.001). When only remission marrows at 24 months were analyzed, PFS was 4.7-fold lower among GAGE-positive patients. Thirty-seven percent of N6 patients were positive for GAGE, in contrast to 17% of the patients in the more current regimen N7.

CONCLUSIONS

The detection of GAGE by RT-PCR in marrow may have utility in molecular staging of patients in clinical remission. It may allow earlier identification of patients at risk, such that appropriate intervention can be given before clinical relapse. GAGE may also serve as a surrogate endpoint for adjuvant treatment strategies, and to determine the duration of therapy.

Laser-capture microdissected schwannian and neuroblastic cells in stage 4 neuroblastomas have the same genetic alterations

BACKGROUND

Neuroblastoma (NB) is a heterogeneous tumor composed of mixed populations of neuroblastic, Schwannian, and gangliocytic cells.

PROCEDURE

We examined the genetic lineage of Schwannian and neuroblastic cells in stage 4 NB using laser-capture microdissection (LCM) and allelic analysis of microsatellite markers of chromosomes 1p, 11q, and 14q.

RESULTS

In 18 out of 19 cases, individual cell types exhibited the same allelotype.

CONCLUSION

Our results provide evidence that the majority of Schwannian and neuroblastic cells in stage 4 NB are of neoplastic origin, and support the hypothesis of a tumor stem cell capable of development along multiple lineages.

Prognostic significance of EPHB6, EFNB2, and EFNB3 expressions in neuroblastoma

BACKGROUND

EPH family receptor tyrosine kinases and their ligand ephrins play pivotal roles in development. High-level expression of transcripts encoding EPHB6 receptors (EPHB6), its ligands ephrin-B2 and ephrin-B3 (EFNB2, EFNB3) is predictive of favorable disease outcome of neuroblastoma (NB). When combined with TrkA expression, the expression of EPHB6, EFNB2, or EFNB3 predicts more accurately the disease outcome than each of the four variables alone.

PROCEDURE

Cox regression and Kaplan-Meier analyses were used to assess the prognostic significance of EPHB6, EFNB2, EFNB3, and TrkA expressions in NB without MYCN amplification.

RESULTS

High-level expression of EFNB3 or TrkA predicted favorable NB outcome of NB without MYCN amplification (p < 0.03). As found in the general NB population, EPHB6, EFNB2, or EFNB3 expression in combination with TrkA expression was significantly predictive of the disease outcome of normal MYCN NB (p < 0.01).

CONCLUSIONS

EPHB6, EFNB2, and EFNB3 expressions may permit further refinement of the prognostic stratification of NB into favorable and unfavorable groups.

Correlation of anti-idiotype network with survival following anti-G(D2) monoclonal antibody 3F8 therapy of stage 4 neuroblastoma

BACKGROUND

A transient human anti-mouse antibody response was associated with significantly longer survival [Cheung et al. (1998): J Clin Oncol 16:3053] following antibody 3F8 (Ab1) treatment. We postulate that the induction of an idiotype network which included anti-anti-idiotypic (Ab3) and anti-G(D2) (Ab3') responses is associated with tumor control.

PROCEDURE

Thirty-four patients with stage 4 neuroblastoma (NB) diagnosed at > 1 year of age were treated with anti-G(D2) monoclonal antibody 3F8 at the end of chemotherapy

RESULTS

Long-term progression-free survival and overall survival correlated significantly with Ab3' andAb3, but not with non-idiotypic antibody responses. Only one of six individual specificities showed significant correlations with patient survival.

CONCLUSIONS

As in vitro correlates of idiotype network initiated by Ab1 treatment, Ab3 and Ab3' may provide convenient biologic endpoints for monoclonal antibody therapy of advanced NB, and a rationale for choosing specific anti-idiotypic antibodies for vaccine development.

Cost effectiveness analysis of intravenous ketorolac and morphine for treating pain after limb injury: double blind randomised controlled trial

OBJECTIVES

To investigate the cost effectiveness of intravenous ketorolac compared with intravenous morphine in relieving pain after blunt limb injury in an accident and emergency department.

DESIGN

Double blind, randomised, controlled study and cost consequences analysis.

SETTING

Emergency department of a university hospital in the New Territories of Hong Kong.

PARTICIPANTS

148 adult patients with painful isolated limb injuries (limb injuries without other injuries).

MAIN OUTCOME MEASURES

Primary outcome measure was a cost consequences analysis comparing the use of ketorolac with morphine; secondary outcome measures were pain relief at rest and with limb movement, adverse events, patients' satisfaction, and time spent in the emergency department.

RESULTS

No difference was found in the median time taken to achieve pain relief at rest between the group receiving ketorolac and the group receiving morphine, but with movement the median reduction in pain score in the ketorolac group was 1.09 per hour (95% confidence interval 1.05 to 2.02) compared with 0.87 (0.84 to 1.06) in the morphine group (P=0.003). The odds of experiencing adverse events was 144.2 (41.5 to 501.6) times more likely with morphine than with ketorolac. The median time from the initial delivery of analgesia to the participant leaving the department was 20 (4.0 to 39.0) minutes shorter in the ketorolac group than in the morphine group (P=0.02). The mean cost per person was $HK44 ( pound4; $5.6) in the ketorolac group and $HK229 in the morphine group (P<0.0001). The median score for patients' satisfaction was 6.0 for ketorolac and 5.0 for morphine (P<0.0001).

CONCLUSION

Intravenous ketorolac is a more cost effective analgesic than intravenous morphine in the management of isolated limb injury in an emergency department in Hong Kong, and its use may be considered as the dominant strategy.

Granulocyte-colony stimulating factor and multiple cycles of strongly myelosuppressive alkylator-based combination chemotherapy in children with neuroblastoma

BACKGROUND

The authors assessed key effects of granulocyte-colony stimulating factor (G-CSF) used prophylactically with multiple cycles of strongly myelosuppressive alkylator-based combination chemotherapy. To the authors' knowledge, no large study has focused on G-CSF in this setting, yet this kind of treatment has recently become standard for poor risk pediatric solid tumors such as neuroblastoma. PATIENTS AND METHODS. Children with neuroblastoma received cyclophosphamide 140 mg/kg (i.e., 4200 mg/m(2)), doxorubicin 75 mg/m(2), and vincristine (CAV) in cycles 1, 2, 4, and 6 and cisplatin 200 mg/m(2) and etoposide 600 mg/m(2) (P/VP) in cycles 3, 5, and 7. To maximize dose intensity, chemotherapy was begun as soon as the absolute neutrophil count (ANC) was > or = 500/microL and platelet count was > or = 100,000/microL. No cytokines were used during 1990-1994 (control group; n = 28), but G-CSF was used from 1995 to 1998 (G-CSF group; n = 30) at 5 microg/kg/day subcutaneously from 1 day after chemotherapy until the ANC was > or = 500/microL on 2 successive days or was > or = 1000/microL.

RESULTS

Each cycle of CAV decreased ANCs to < 200/microL in all 58 patients; recovery to 200/microL and to 500/microL was significantly sooner with G-CSF. In contrast, P/VP did not invariably cause severe neutropenia: similar numbers of patients in each group maintained ANCs > or = 200/microL and > or = 500/microL; recovery to 500/microL (but not to 200/microL) was significantly faster in the G-CSF group. G-CSF had no impact on rates of febrile episodes. Bacterial/fungal infections were slightly less frequent in the G-CSF group with CAV (P = 0.11) but not with P/VP. Dose intensity through cycle 4 was the same in both groups. Beginning with cycle 3, G-CSF patients had slower recovery to platelet counts > or = 100,000/microL. Response rates were similar in the two groups.

CONCLUSIONS

With multiple cycles of strongly myelosuppressive alkylator-based combination chemotherapy, prophylactic use of G-CSF hastened ANC recovery but did not reduce the incidence of febrile episodes, had little impact on infection rates, did not yield augmented dose intensity, was associated with prolonged thrombocytopenia, and had no effect on response rates of neuroblastoma. The data support more limited use of G-CSF.

Pilot study of topotecan and high-dose cyclophosphamide for resistant pediatric solid tumors

BACKGROUND

The recommended dosages of topotecan and cyclophosphamide in combination for prior-treated patients-3.75 mg/m(2) and 1,250 mg/m(2) in children, 5 mg/m(2) and 600 mg/m(2) in adults, respectively-are well below those of each agent when used singly. We tested the hypothesis that much higher dosing would meet critical goals of salvage therapy: antitumor effect and a lack of toxicity to key organs, so as not to preclude subsequent consolidative treatments needed for cure.

PROCEDURE

Patients with resistant pediatric solid tumors received cyclophosphamide 4,200 mg/m(2) by 48 hr infusion, and topotecan 6 mg/m(2) by 72 hr infusion (HD-Cy/Topo). Mesna and granulocyte colony-stimulating factor were used. Cycles were repeated when neutrophil counts were >1,000/uL and platelet counts were >75,000/uL.

RESULTS

Twenty-eight patients, aged 2 to 33 years (median, 14), received one (n = 4), two (n = 15), or > or =3 (n = 9) cycles of HD-Cy/Topo. All patients had previously received > or =6 cycles of other therapy, high-dose alkylator-based chemotherapy, and/or etoposide- and doxorubicin-containing regimens. HD-Cy/Topo was given in an outpatient setting. Profound myelosuppression was the major toxicity, but retreatment was possible by day 28, and preliminary results with peripheral blood stem cell collections showed a sparing effect on hemopoietic stem cells. Mucositis was uncommon. After HD-Cy/Topo, cardiac, renal, hepatic, and pulmonary function remained within the normal range. Partial or minor responses were noted in neuroblastoma, desmoplastic small round-cell tumor, Ewing sarcoma, rhabdomyosarcoma, and osteosarcoma.

CONCLUSIONS

Its antitumor potential and limited toxicity make HD-Cy/Topo an attractive choice for inclusion in aggressive salvage programs aimed at achieving cures of resistant tumors. It may also merit incorporation into frontline treatment protocols.

Monoclonal antibody-based therapy for neuroblastoma

Dose-intensive combination chemotherapy can improve the clinical response of many pediatric solid tumors. However, cure remains elusive. Stage 4 neuroblastoma stands out as an exception. Part of this success is a result of antibody-based strategies, which include immunomagnetic purging of autologous marrow prior to autologous marrow transplantation and immunotherapy directed at minimal residual disease. It is striking that treatment with monoclonal antibodies, even when targeted at a single antigen, namely, ganglioside G(D2), can affect long-term progression-free survival among these patients. The potential role of the idiotype network in tumor control can be exploited clinically. The genetic engineering of these antibodies into novel forms holds great promise for more specific and effective targeting possibilities, including the delivery of cytokines and cells. Preclinical results are also promising. It is expected that the availability of novel antibodies directed at a broader spectrum of pediatric solid tumors will facilitate the successful application of this approach to more patients. Experience with metastatic neuroblastoma has provided proof of this principle. It is likely that other tumors will fall.

Implications of EPHB6, EFNB2, and EFNB3 expressions in human neuroblastoma

Neuroblastoma (NB) is a common pediatric tumor that exhibits a wide range of biological and clinical heterogeneity. EPH (erythropoietin-producing hepatoma amplified sequence) family receptor tyrosine kinases and ligand ephrins play pivotal roles in neural and cardiovascular development. High-level expression of transcripts encoding EPHB6 receptors (EPHB6) and its ligands ephrin-B2 and ephrin-B3 (EFNB2, EFNB3) is associated with low-stage NB (stages 1, 2, and 4S) and high TrkA expression. In this study, we showed that EFNB2 and TrkA expressions were associated with both tumor stage and age, whereas EPHB6 and EFNB3 expressions were solely associated with tumor stage, suggesting that these genes were expressed in distinct subsets of NB. Kaplan-Meier and Cox regression analyses revealed that high-level expression of EPHB6, EFNB2, and EFNB3 predicted favorable NB outcome (P<0.005), and their expression combined with TrkA expression predicted the disease outcome more accurately than each variable alone (P<0.00005). Interestingly, if any one of the four genes (EPHB6, EFNB2, EFNB3, or TrkA) was expressed at high levels in NB, the patient survival was excellent (>90%). To address whether a good disease outcome of NB was a consequence of high-level expression of a "favorable NB gene," we examined the effect of EPHB6 on NB cell lines. Transfection of EPHB6 cDNA into IMR5 and SY5Y expressing little endogenous EPHB6 resulted in inhibition of their clonogenicity in culture. Furthermore, transfection of EPHB6 suppressed the tumorigenicity of SY5Y in a mouse xenograft model, demonstrating that high-level expressions of favorable NB genes, such as EPHB6, can in fact suppress malignant phenotype of unfavorable NB.

Comparison of in vitro antibody-targeted cytotoxicity using mouse, rat and human effectors

Antibodies can direct tumor cell lysis by activating complement-mediated and cell-mediated cytoxicities (antibody-dependent cell-mediated cytotoxicity, ADCC). Clinical translation of these effects into successful cancer therapy has been slow. Choosing an appropriate animal model to test new therapeutic strategies is difficult because of species differences in immunological effector functions. In previous work, we found that an unmodified anti-ganglioside mouse IgG3 monoclonal antibody (mAb), 3F8, could successfully treat clinical tumors in humans and experimental tumors in rats but not experimental tumors in mice. We explored the reasons for this species difference by performing in vitro antibody-dependent cytotoxicity assays comparing the potency of polymorphonuclear neutrophils (PMN), natural killer (NK) cells and complement from the three species: mouse, rat and human. 3F8-dependent complement-mediated cytotoxicity produced more than 70% specific release when human and rat sera were used and only 20% with mouse serum. PMN-mediated ADCC was 35%-70% with human effectors, 25%-60% with rat and undetectable with mouse. Human eosinophils did not contribute to this ADCC. Cytotoxicity utilizing interleukin-2-activated NK cells was antibody-independent in all three species but the specific release was 60%-70% with human and rat NK cells and 10% with mouse NK cells. These data suggest that, for mouse IgG3, the rat may provide a more relevant rodent model than the mouse for testing the in vivo antitumor effects of monoclonal antibodies.

Induction of Ab3 and Ab3' antibody was associated with long-term survival after anti-G(D2) antibody therapy of stage 4 neuroblastoma

Treatment with anti-G(D2) monoclonal antibody 3F8 (Ab1) at the time of remission may prolong survival for children with stage 4 neuroblastoma. A transient human antimouse antibody (HAMA) response was associated with significantly longer survival (Cheung et al., J. Clin. Oncol., 16: 3053-3060, 1998). Because this response was primarily anti-idiotypic (Ab2), we postulate that the subsequent induction of an idiotype network that included an elevation of anti-anti-idiotypic (Ab3) and anti-G(D2) (Ab3') antibody titers may be responsible for tumor control. Thirty-four patients with stage 4 neuroblastoma diagnosed at >1 year of age were treated with 3F8 at the end of chemotherapy. Most had either bone marrow (31 of 34) or distant bony (29 of 34) metastases at diagnosis. Thirteen patients were treated at second or subsequent remission, and 12 patients in this group had a history of progressive/persistent disease after bone marrow transplantation; 21 patients were treated in the first remission after N6 chemotherapy. Their serum HAMA, Ab3, and Ab3' titers prior to, at 6, and at 14 months after antibody treatment were measured by ELISA. Among these 34 patients, 14 are alive, and 13 (1.8-7.4 years at diagnosis) are progression free (53-143 months from the initiation of 3F8 treatment) without further systemic therapy. Long-term progression-free survival (PFS) and survival correlated significantly with Ab3' (anti-G(D2)) response at 6 months and with Ab3 response at 6 and 14 months. By defining Ab3 threshold ranging from the ratio of 1.1 to 2.6 above pretreatment level, the difference in PFS and survival between the high-Ab3 and low-Ab3 groups became markedly widened. Similarly, increasing the Ab3' threshold at either 6 or 14 months to 300% above pre-3F8 levels also increased the spread between the high versus low Ab3' groups for both PFS and survival curves. Non-idiotype antibody responses (anti-mouse-IgG3 or anti-tumor nuclear HUD antigen) had no apparent impact on PFS or survival. In conclusion, despite the high-risk nature of stage 4 neuroblastoma, long-term remission without myeloablative therapy can be achieved with 3F8 treatment. Ab3 and Ab3' antibody response correlated with prolonged PFS and survival. We postulate that successful induction of an idiotype network in patients may be responsible for long-term tumor control.