Significant Clinical Improvement Was Predicted in a Cohort of Patients With Low Back Pain Early in the Care Process

OBJECTIVE

The purpose of this study was to determine the proportion of patients with low back pain who achieved clinical improvement in disability within 3 or 6 physical therapy visits, identify factors that predicted improvement, and predict the probability of improvement by the third and sixth visits.

METHODS

This retrospective, observational study looked at patients (N = 6523) who completed a numeric pain scale and Modified Low Back Disability Questionnaire (MDQ) at every visit. Four prediction models were developed: 30% improvement by visit 3 and by visit 6 and 50% improvement by visit 3 and by visit 6. A logistic regression model was fit to predict patients' improvement in disability using the MDQ. Predictive models used age, disability scores, sex, symptom duration, and payer type as factors. Receiver operating characteristic curves and area under the curve were computed for the models. Nomograms illustrate the relative impacts of the predictor variables.

RESULTS

Disability improved 30% in 42.7% of patients by visit 3 and 49% by visit 6. Disability improved 50% in 26% of patients by visit 3 and 32.9% by visit 6. First visit score (MDQ1) was strongest factor to predict 30% improvement by visit 3. The visit 3 score (MDQ3) was strongest factor to predict a 30% or 50% improvement by visit 6. The combination of MDQ1 and MDQ3 scores was strongest overall predictive factor for visit 6. The area under the curve values for models using only the MDQ1 and MDQ3 scores to predict 30% or 50% improvement by the sixth visit were 0.84 and 0.85, respectively, representing excellent overall diagnostic accuracy of the prediction models.

CONCLUSION

Excellent discrimination to predict patients' significant clinical improvement by visit 6 using 2 outcome scores was demonstrated. Gathering outcomes routinely enhances assessment of prognosis and clinical decision making.

IMPACT

Understanding prognosis of clinical improvement supports physical therapists' contribution to value-based care.

Variation in Outcomes and Number of Visits Following Care Guideline Implementation: Part 2 of an Analysis of 12 355 Patients After Total Knee Arthroplasty

OBJECTIVE: To describe the variation in outcomes and number of visits before and after implementing a care guideline for total knee arthroplasty (TKA) rehabilitation. DESIGN: Nonrandomized intervention study. METHODS: We compared 2558 patients with TKA who received care that was not standardized (non-care guideline [NCG] group) to 9797 patients with TKA who received care according to the care guideline (CG). We fit 2 Bayesian hierarchical linear regression models using the Knee Outcome Survey - Activities of Daily Living (KOS-ADL) change score and number of physical therapy (PT) visits as the response variables, controlling for relevant predictor variables. We also compared the ratio of the standard deviations of the KOS-ADL change scores and the number of PT visits within and between clinics. RESULTS: The overall estimated mean improvement in KOS-ADL change score was 23.0 points (95% confidence interval [CI]: 20.3, 25.7) in the NCG group and 28.7 points (95% CI: 27.5, 29.7) in the CG group; the mean difference was 5.6 (2.7-8.6). Mean KOS-ADL change scores were higher in the CG group than the NCG group in every clinic, although only 8 clinics improved significantly. The number of PT visits did not change meaningfully (NCG: mean, 10.7 [95% CI: 9.9, 11.5]; CG: mean, 10.5 [95% CI: 9.9, 10.9]). Variation in KOS-ADL change score decreased by 4% within clinics (CG-NCG ratio: 0.96 [95% CI: 0.93, 0.99]) and 63% between clinics (CG-NCG ratio: 0.37 [95% CI: 0.21, 0.62]). Variation in number of visits decreased by 7% within clinics (CG-NCG ratio: 0.93 [95% CI: 0.90, 0.96]) and 19% between clinics (CG-NCG ratio: 0.81 [95% CI: 0.39, 1.49]). CONCLUSION: Implementing a care guideline for TKA rehabilitation may improve outcomes and reduce unwarranted variation in practice within clinics and especially between clinics within a large health care system. J Orthop Sports Phys Ther 2023;53(3):151-158. Epub: 12 December 2022. doi:10.2519/jospt.2022.11370.

Natural Language Processing Performance for the Identification of Venous Thromboembolism in an Integrated Healthcare System

Real-time identification of venous thromboembolism (VTE), defined as deep vein thrombosis (DVT) and pulmonary embolism (PE), can inform a healthcare organization's understanding of these events and be used to improve care. In a former publication, we reported the performance of an electronic medical record (EMR) interrogation tool that employs natural language processing (NLP) of imaging studies for the diagnosis of venous thromboembolism. Because we transitioned from the legacy electronic medical record to the Cerner product, iCentra, we now report the operating characteristics of the NLP EMR interrogation tool in the new EMR environment. Two hundred randomly selected patient encounters for which the imaging report assessed by NLP that revealed VTE was present were reviewed. These included one hundred imaging studies for which PE was identified. These included computed tomography pulmonary angiography-CTPA, ventilation perfusion-V/Q scan, and CT angiography of the chest/ abdomen/pelvis. One hundred randomly selected comprehensive ultrasound (CUS) that identified DVT were also obtained. For comparison, one hundred patient encounters in which PE was suspected and imaging was negative for PE (CTPA or V/Q) and 100 cases of suspected DVT with negative CUS as reported by NLP were also selected. Manual chart review of the 400 charts was performed and we report the sensitivity, specificity, positive and negative predictive values of NLP compared with manual chart review. NLP and manual review agreed on the presence of PE in 99 of 100 cases, the presence of DVT in 96 of 100 cases, the absence of PE in 99 of 100 cases and the absence of DVT in all 100 cases. When compared with manual chart review, NLP interrogation of CUS, CTPA, CT angiography of the chest, and V/Q scan yielded a sensitivity = 93.3%, specificity = 99.6%, positive predictive value = 97.1%, and negative predictive value = 99%.

Antimicrobial Stewardship in a Hematological Malignancy Unit: Carbapenem Reduction and Decreased Vancomycin-Resistant Enterococcus Infection

BACKGROUND

Antibiotic stewardship is challenging in hematological malignancy patients.

METHODS

We performed a quasiexperimental implementation study of 2 antimicrobial stewardship interventions in a hematological malignancy unit: monthly antibiotic cycling for febrile neutropenia that included cefepime (± metronidazole) and piperacillin-tazobactam and a clinical prediction rule to guide anti-vancomycin-resistant Enterococcus faecium (VRE) therapy. We used interrupted time-series analysis to compare antibiotic use and logistic regression in order to adjust observed unit-level changes in resistant infections by background community rates.

RESULTS

A total of 2434 admissions spanning 3 years pre- and 2 years postimplementation were included. Unadjusted carbapenem and daptomycin use decreased significantly. In interrupted time-series analysis, carbapenem use decreased by -230 days of therapy (DOT)/1000 patient-days (95% confidence interval [CI], -290 to -180; P < .001). Both VRE colonization (odds ratio [OR], 0.64; 95% CI, 0.51 to 0.81; P < .001) and infection (OR, 0.41; 95% CI, 0.2 to 0.9; P = .02) decreased after implementation. This shift may have had a greater effect on daptomycin prescribing (-160 DOT/1000 patient-days; 95% CI, -200 to -120; P < .001) than did the VRE clinical prediction score (-30 DOT/1000 patient-days; 95% CI, -50 to 0; P = .08). Also, 46.2% of Pseudomonas aeruginosa isolates were carbapenem-resistant preimplementation compared with 25.0% postimplementation (P = .32). Unit-level changes in methicillin-resistant Staphylococcus aureus and extended-spectrum beta lactamase (ESBL) incidence were explained by background community-level trends, while changes in AmpC ESBL and VRE appeared to be independent. The program was not associated with increased mortality.

CONCLUSIONS

An antibiotic cycling-based strategy for febrile neutropenia effectively reduced carbapenem use, which may have resulted in decreased VRE colonization and infection and perhaps, in turn, decreased daptomycin prescribing.

A model for predicting emergency physician opinion of electrocardiogram tracing data quality

BACKGROUND

Limited work has established an objective measure of ECG quality that correlates with physician opinion of the study. We seek to establish a threshold of acceptable ECG data quality for the purpose of ruling out STEMI derived from emergency physician opinion.

METHODS

A panel of three emergency physicians rated 240 12-Lead ECGs as being acceptable or unacceptable data quality. Each lead of the ECG had the following measurements recorded: baseline wander, QRS signal amplitude, and artifact amplitude. A lasso regression technique was used to create the model.

RESULTS

The area under the curve for the model using all 36 elements is 1.0, indicating a perfect fit. A simplified model using 22 terms has an area under the curve of 0.994.

CONCLUSIONS

This study demonstrated that emergency physician opinion of ECG quality for the purpose of ruling out STEMI can be predicted through a regression model.

Responsiveness to Change of Functional Limitation Reporting: Cross-sectional Study Using the Intermountain ROMS Scale in Outpatient Rehabilitation

BACKGROUND

The Centers for Medicare and Medicaid Services (CMS) require physical therapists document patients' functional limitations. The process is not standardized. 
A systematic approach to determine a patient's functional limitations and responsiveness to change is needed.

OBJECTIVE

The purpose of this study is to compare patient-reported outcomes (PROs) responsiveness to change using 7-level severity/complexity modifier scale proposed by Medicare to a derived scale implemented by Intermountain Healthcare's Rehabilitation Outcomes Management System (ROMS).

DESIGN

This was a retrospective, observational cohort design.

METHODS

165,183 PROs prior to July 1, 2013, were compared to 46,334 records from July 1, 2013, to December 31, 2015. Histograms and ribbon plots illustrate distribution and change of patients' scores. ROMS raw score ranges were calculated and compared to CMS' severity/complexity levels based on score percentage. Distribution of the population was compared based on the 2 methods. Sensitivity and specificity were compared for responsiveness to change based on minimal clinically important difference (MCID).

RESULTS

Histograms demonstrated few patient scores placed in CMS scale levels at the extremes, whereas the majority of scores placed in 2 middle levels (CJ, CK). ROMS distributed scores more evenly across levels. Ribbon plots illustrated advantage of ROMS' using narrower score ranges. Greater chance for patients to change levels was observed with ROMS when an MCID was achieved. ROMS narrower scale levels resulted in greater sensitivity and good specificity.

LIMITATIONS

Geographic representation for the United States was limited. Without patients' global rating of change, a reference standard to gauge validation of improvement could not be provided.

CONCLUSIONS

ROMS provides a standard approach to identify accurately functional limitation modifier levels and to detect improvement more accurately than a straight across transposition using the CMS scale.

Carbon monoxide poisoning in Utah: 1996-2013

INTRODUCTION

The true incidence of carbon monoxide (CO) poisoning is not clearly known, but a description of possible trends could aid in prevention.

METHODS

Investigators searched Utah state databases for emergency department (ED) visits and admissions for CO poisoning and medical examiner records for CO-related fatalities.

RESULTS

From 1996-2013, 7,590 individuals were diagnosed with CO poisoning: 6,469 were treated/ released from EDs; 596 were admitted; 525 died. Of 7,065 non-fatal poisonings, 5,950 (84%) were accidental and 498 (7%) were suicide attempts. Few patients (9.7%) were treated with hyperbaric oxygen. For accidental poisonings, internal combustion engines accounted for 43%, smoke inhalation, 34%, and heating sources, 22%. Internal combustion engines were implicated in 97% of suicide attempts. Non-fatal poisonings declined following a 2008 legislative change requiring CO alarms in residences, but we do not know if legislation caused the decline. One hundred forty-one (27%) fatal poisonings were accidental, 361 (70%) suicides and two (0.4%) homicides. Victims with cardiovascular autopsy findings/past cardiovascular history had lower carboxyhemoglobin levels (mean 51.2%, n=53) compared to those without (70.8%, n=472). Mean postmortem carboxyhemoglobin was highest in ages 20-29 years (72.5%).

CONCLUSIONS

The incidence of CO poisoning in Utah is declining, but CO poisoning is still common. Alarm legislation may aid prevention efforts. An educational campaign addressing the many causes and circumstances of CO poisoning is required for prevention.

Impact of Medication Reconciliation on Medication Error Rates in Community Hospital Cardiac Care Units

Background/Objective

Medication reconciliation has become a practice standard across the country. We conducted a prospective study to measure the impact of medication reconciliation on the rates of medication error in cardiac care units.

Methods

We used 2 cardiac care units of similar size and case mix index (a measure of patient acuity) at separate hospitals to measure the difference in changes in medication error rates when medication reconciliation was implemented in the study unit, but not the control unit. A total of 457 patients were enrolled. Medication histories were recorded and compared with medication orders at admission to the units and upon transfer or discharge from the units. Errors were categorized as omission, incorrect drug order details, therapeutic duplication, missing information, medication allergy, drug interaction, incorrect therapeutic substitution, or contraindication. Adjudication of errors was done by a 3-pharmacist panel that was blinded to study group. A Poisson regression model was used to determine the significance of the difference in error rate changes between the study and control units.

Results

Errors were found in 325 of 7,203 orders reviewed (4.5%). Medication error rates decreased from 7.2% to 3.4% in the study group (3.8% absolute error reduction) and from 4.3% to 3.3% in the control group (1% absolute error reduction). The difference in changes in error rates between groups was statistically significant ( P < .0001).

Conclusion

Medication reconciliation has been one of the most costly and difficult health care quality improvement initiatives in recent history. Based on our findings, it appears that significant reductions in medication errors, the primary purpose for its implementation, can be achieved.

Comparison of standard Maze III and radiofrequency Maze operations for treatment of atrial fibrillation

OBJECTIVE

This study compares clinical results of the standard Maze III operation, a highly effective treatment for atrial fibrillation, to less complex variations of the Maze III operation utilizing unipolar and bipolar radiofrequency ablation and pulmonary vein isolation.

METHODS

Records were reviewed of 377 patients who had operations for treatment of atrial fibrillation at a single institution over a 10-year period. Standard Maze III was performed in 220 patients, unipolar radiofrequency Maze III in 60, bipolar radiofrequency Maze III in 65, and radiofrequency pulmonary vein isolation in 32. Electrocardiograms were obtained at discharge and 3-, 6-, and 12-month intervals. Chi-square test, logistic regression, and Bayesian theory analyses were performed to determine significant associations between operative procedures and outcomes.

RESULTS

Mean age was 65.1 years (range 22-87). There were 13 hospital deaths (3.4%) and 16 deaths during follow-up. Most patients (90.2%, 340/377) had concomitant operations. Electrocardiogram analysis was available in 344 patients at 3 months and 313 patients at 6 months. Freedom from atrial fibrillation at 6 months was superior after standard Maze III compared with radiofrequency modifications. Subanalysis according to surgeon experience demonstrated good results regardless of operative experience.

CONCLUSIONS

This single-institution experience suggests that the standard Maze III operation is superior to radiofrequency operations for treatment of atrial fibrillation. Radiofrequency modifications of the Maze III operation are also effective treatments for atrial fibrillation and can achieve good results regardless of surgeon experience.

Prostate-Specific Antigen Control with Low-Dose Adjuvant Radiotherapy for High-Risk Prostate Cancer

OBJECTIVES

To analyze the prostate-specific antigen (PSA) outcome after low-dose adjuvant RT at a single institution, because the role and optimal dose of external beam radiotherapy (RT) after radical prostatectomy for prostate cancer remain controversial.

METHODS

We retrospectively identified 65 men who had received low-dose adjuvant RT (median 50 Gy) for microscopically positive margins with an undetectable postoperative PSA from 1990 to 2004. Biochemical failure-free survival was the primary endpoint. Biochemical failure was defined as two consecutive PSA increases to greater than 0.2 ng/mL.

RESULTS

At a median follow-up of 5 years, 2 men had developed distant metastasis, 2 had local recurrence, and 2 had died (neither attributable to prostate cancer). Biochemical failure had occurred in 7 men (11%). The 5 and 8-year rate of biochemical failure-free survival was 87%. A greater Gleason score (P = 0.04) and seminal vesicle invasion (P = 0.04) predicted significantly for increased biochemical failure on univariate analysis. No single factor was significant on multivariate analysis. Men with a Gleason score of 7 or less had a 5-year biochemical failure-free survival rate of more than 90%. In contrast, those with a Gleason score of 8 or more had a 50% risk of biochemical failure at 5 years. Acute bowel or bladder toxicity (all grade 2 or less) developed in 25%. Two men developed chronic urethral stricture requiring dilation, and 34 (51%) developed surgery-related toxicity that persisted throughout and after RT.

CONCLUSIONS

Low-dose RT is well tolerated and can potentially provide PSA control in men with Gleason score 7 or less disease with positive surgical margins after radical prostatectomy.

CD34+ cell adhesion molecule profiles differ between patients mobilized with granulocyte-colony-stimulating factor alone and chemotherapy followed by granulocyte-colony-stimulating factor

BACKGROUND

High-dose therapy with autologous peripheral blood progenitor cell support is widely utilized but requires successful CD34+ cell mobilization and collection. Chemotherapy plus growth factors appear to mobilize more CD34+ cells than growth factors alone. Because alterations in expression of adhesion molecules are important in the trafficking of hematopoietic progenitors, the possibility was explored that the mechanism of this superior mobilization may be greater down regulation of adhesion molecules.

STUDY DESIGN AND METHODS

The expression of eight adhesion molecules (CD11a, b, and c; 15s; 49d and e; 54; and 62L) on the collected CD34+ cells from 15 patients undergoing mobilization with chemotherapy plus granulocyte-colony-stimulating factor (G-CSF) was compared with those of 14 concomitant patients receiving G-CSF alone.

RESULTS

Patients receiving chemotherapy plus G-CSF mobilized more CD34+ cells and did not differ in prior chemotherapy or radiation. There were no significant differences in the percentage of CD34+ cells expressing any of the adhesion molecules examined between the two groups. The chemotherapy plus G-CSF-mobilized cells consistently showed higher expression intensity, and this showed significance or a strong trend for CD11a and c, CD15s, and CD54. Despite these higher expression levels, there were no differences in engraftment kinetics.

CONCLUSIONS

CD34+ cells mobilized by chemotherapy plus growth factors appear to have higher intensities of expression of several adhesion molecules. The significance of this observation will require further study.

Long-term results of organ preservation in chondrosarcoma of the cricoid

Chondrosarcoma of the larynx is rare. The posterolateral lamina of the cricoid cartilage is the site most commonly involved. Although the symptomology, radiological and histopathological diagnostic features are well known, the condition continues to be diagnosed late and recurrences after excision are common. In general, radical surgical excision can result in long-term remission, although prognosis is related to the histopathological grade of the tumor. While a conservative surgical approach in low-grade tumors is justified, unexplained hoarseness, unilateral vocal cord paralysis and dyspnea requires CT scan examination.

Carcinoma of the ethmoid: results of treatment with conventional surgery and post-operative radiotherapy

AIMS

A retrospective study was carried out of 50 patients with carcinoma of the ethmoid, treated over a period of 20 years.

METHODS

The treatment used was surgery, followed by post-operative external beam radiotherapy and when possible supplemented by brachytherapy.

RESULTS

Although the nature of surgery in the majority of cases was conventional, the 63% 5-year overall survival, except in adenocarcinomas, was slightly better than that achieved by more aggressive surgery. There was no mortality and morbidity was minimal.

CONCLUSIONS

Conventional surgery in combination with radiotherapy and brachytherapy gives satisfactory and comparable results.

Studies of the anatomy and pathology of the orbit in carcinoma of the maxillary sinus and their impact on preservation of the eye in maxillectomy

BACKGROUND

The periorbita has been traditionally regarded as the decisive layer whose involvement in carcinoma of maxillary sinus indicates orbital exenteration. Anatomic texts depict that the orbital fat rests on the periorbita. Our experience at surgical dissections has been different.

METHODS

Twenty-five patients underwent total maxillectomy for advanced (T3-T4) carcinoma of the maxillary sinus with postoperative radiotherapy during a 15-year period between 1981 and 1995. In 11 patients, despite radiologic evidence of orbital invasion, and in 5 patients with infiltration of the periorbita, the eye could be preserved without evidence of recurrence. In 6 patients who in addition underwent orbital exenteration, histopathologic evidence of tumor invasion of the orbit was present in only one surgical specimen.

RESULTS

Clinicoanatomic studies have clearly shown the presence of a thin, distinct fascial layer which surrounds the periocular fat and separates it from the periorbita. Neither clinical examination nor imaging could predict orbital invasion with absolute accuracy. Histopathologic examination of the surgical specimens shows that tumor infiltration of the eye is rare.

CONCLUSION

Periocular fat is surrounded by a thin fascial layer and is not in direct contact with the periorbita. Intraoperative decision making with respect to preservation of the eye is sometimes essential.

Effect of combination antiretroviral therapy upon rectal mucosal HIV RNA burden and mononuclear cell apoptosis

BACKGROUND

Pathogen-negative diarrhea is common in HIV infection and has been associated with clinical symptoms, histopathology, HIV expression, CD4+ lymphocyte depletion, cytokine mRNA expression, and apoptosis of lamina propria mononuclear cells.

OBJECTIVES AND METHODS

To examine the short-term (7-day) effects of treatment with combination antiretroviral therapies upon gastrointestinal symptoms and rectal mucosa in 15 HIV-infected subjects.

RESULTS

Treatment was associated with significant decreases in the perception of abdominal bloating and cramps. Similar declines in RNA burden and rises in CD4+ lymphocyte counts were found in blood and mucosa. Treatment was also associated with a fall in the number of lamina propria mononuclear cells undergoing apoptosis by in situ labeling, a change that correlated with the change in mucosal viral burden.

CONCLUSIONS

Peripheral blood and mucosal compartments are equally responsive to effective antiretroviral therapies. The detection of significant changes within 7 days of starting antiviral therapy implies that intestinal dysfunction may be a direct result of local HIV infection.

Selective depletion of rectal lamina propria rather than lymphoid aggregate CD4 lymphocytes in HIV infection

The goal of this study was to examine the changes in lymphocyte populations in rectal mucosa during HIV infection and to study their relationship to mucosal immunity and to systemic depletion of CD4 lymphocytes. Rectal biopsies from 58 HIV-infected subjects and eight controls were studied. Frozen rectal tissue sections were stained with antibodies to CD4, CD3, CD8, and markers for macrophages. HIV-infected subjects were divided into early stage (no opportunistic infections) and AIDS groups. There was profound depletion of rectal lamina propria CD4 lymphocytes (16% and 6% of normal content in early and AIDS groups, respectively). However, lymphoid aggregate CD4 lymphocytes were far less severely depleted (69% and 40% of normal content, respectively). The extent of lymphoid aggregate CD4 lymphocyte depletion generally parallelled the CD4 lymphocyte depletion in the blood. CD8 lymphocyte content in both the lamina propria and lymphoid aggregates usually were increased, particularly in early-stage patients. Macrophage contents were usually normal in the HIV-infected groups. We conclude that rectal lamina propria and lymphoid aggregates are distinct compartments differing markedly in their CD4 lymphocyte content during HIV infection. In light of this and an increased number of apoptotic cells which were noted in rectal lamina propria in HIV-infected subjects, we hypothesize that intestinal lamina propria could be a site of rapid CD4 lymphocyte destruction during HIV infection.

Cytomorphometric parameters in exfoliated cells as biomarkers in head and neck cancer chemoprevention

Quantitative DNA analysis has often been proposed as a potential tool capable of detecting preneoplastic tissue and as such to function as an intermediate endpoint in cancer chemoprevention trials. The first aim of this study was to test whether cytomorphometric parameters could be used to detect field cancerization characteristics in cytological preparations of oral mucosa. Cytomorphometric parameters in exfoliated cells of apparently normal oral mucosa of head and neck cancer patients were compared with those of healthy controls. The second aim was to assess the value of these parameters subsequently as intermediate endpoint biomarkers in the mucosa of 70 patients receiving N-acetylcysteine and/or retinyl-palmitate as chemopreventive drugs. No differences were detected between 'high risk' and healthy mucosa, nor were differences observed before and after treatment.

Progress in radioimmunotherapy of head and neck-cancer (review)

There is an urgent need for an effective adjuvant systemic therapy for the treatment of patients with advanced head and neck cancer. This study shows that therapy based on the use of monoclonal antibodies (MAbs) is developing to a realistic option. A few years ago the first MAbs with specificity for squamous cell carcinoma of the head and neck (HNSCC) were produced, among which was MAb E48. In animal and patient studies, in which localization of radiolabelled MAb E48 was analysed qualitatively and quantitatively, it was demonstrated that a high percentage of the injected dose accumulated selectively in the tumour. These targeting properties, when exploited for delivery of toxic agents to the tumour, give MAb E48 potential for tumour therapy. Especially the application of MAb E48 in radioimmunotherapy (RIT) seems to be attractive due to the intrinsic radiosensitivity of HNSCC. Armed with 186-Rhenium, a radionuclide recently introduced in the field of RIT, MAb E48 IgG was shown to be highly capable of eradicating established HNSCC tumours in nude mice. Complete ablation of small HNSCC was observed in this animal model by a single bolus injection. In an effort to make MAb E48 less antigenic for human application a chimeric human/mouse MAb (cMAb) has been constructed by use of recombinant DNA techniques. This modification strongly improved the capacity of MAb E48 for mediating antibody-dependent cellular cytotoxicity (ADCC). When using this cMAb E48 for RIT of minimal residual disease it can be anticipated that ADCC activity may be supportive to irradiation, especially in the ablation of single disseminated cells or small cell aggregates. Extrapolating results obtained in nude mice to patients and taking into account the good targeting in patients, RIT with E48 IgG seems to have potential for the elimination of minimal residual disease. Based on this encouraging progress, preparations are being made to evaluate the efficacy of Re-186-labelled cMAb E48 as an adjuvant in a phase III study for the treatment of patients who are at high risk for developing distant metastases.

Perspectives of monoclonal antibodies for detection and treatment of head and neck tumours

Monoclonal antibodies (mabs) are potentially powerful tools for the detection and treatment of cancer. To date, only a limited number of mabs are available to head and neck cancer. We produced 5 different groups of mabs to head and neck cancer. These mabs were characterized for their reactivity tumour and non-tumour tissues. Furthermore, biochemical elucidation of recognized antigens was provided. In animal studies the effectiveness of mabs for diagnoses and therapy of cancer is clearly demonstrated. The first results of a clinical study for the detection of head and neck cancer with mabs are shown. Finally, the future of mabs in clinical oncology is discussed.

The use of general primers in the polymerase chain reaction permits the detection of a broad spectrum of human papillomavirus genotypes

A novel polymerase chain reaction (PCR) method was developed that permits the detection of 11 different human papillomavirus (HPV) genotypes using two general primer sets. By computer-assisted sequence analysis, two pairs of general primers were selected from the conserved L1 open reading frame and tested in the PCR on a set of cloned HPV genotypes. Experimental analysis showed that up to three mismatches between primers and target DNA did not influence the efficiency of the assay. The use of these primers in the PCR enabled the detection of HPV genotypes HPV-1a, -6, -8, -11, -13, -16, -18, -30, -31, -32 and -33, and was also successfully applied to well characterized cervical carcinoma cell lines and clinical samples. For the HPV types tested sub-picogram amounts of cloned DNA could be detected after general primer-mediated PCR and subsequent hybridization. The specificity of the amplification products was confirmed by blot hybridization procedures and RsaI restriction enzyme digestion. The results indicate that this PCR method can be a powerful tool for identifying novel HPV genotypes in dysplasias and squamous cell carcinomas suspected of having an HPV aetiology.

The value of postoperative radiotherapy as an adjuvant to radical neck dissection

In this study the results of combined radiotherapy and surgery are compared with the results of surgery alone in patients with neck node metastases from squamous cell carcinomas of the head and neck region. Postoperative radiotherapy decreases the recurrence rate in the neck, especially in cases with histologically established extranodal spread. Results of preoperative radiotherapy were similar to those of irradiation after surgery. Postoperative radiotherapy is favored, because it allows a selection of patients for extra treatment on the base of prognostic information, provided by the histologic characteristics of the neck dissection specimen.