Evaluation of number of target lesions to analyze in time to progression by RECIST

6549

Background: RECIST criteria were designed to evaluated tumor shrinkage and response to therapy by measurement of multiple target lesions, evaluation of non target and new lesions. There is considerable controversy surrounding the optimal number of lesions to assess response, with RECIST requiring the measurement of up to 10 target lesions. These guidelines were set up to evaluate the endpoint of best overall response. Increasingly, time to progression has become an important endpoint in oncology trials. We evaluated the optimal number of lesions to measure to accurately and reproducibly assess time to progression. Methods: We evaluated target lesions metastases in 105 patients enrolled on a Phase III clinical trial. All patients underwent CT at baseline and standard follow up scans until progression. Target lesions were measured unidimensionally and response was assessed according to RECIST by 2 independent Radiologists. A total of 519 target lesions were assessed. Response was calculated according to the rules of target lesions (up to 10) by RECIST, utilizing the 2 largest lesions and randomly selecting 2 target lesions. Results: Using the 2 largest lesions, time to progression was concordant in 83% of cases. The 2 Radiologists determined the two same largest lesions in 89% of cases. Since the determination of the largest or the same target lesions is not always possible or performed, a random selection of 2 target lesions demonstrated a 76% concordance in the time to progression. Conclusions: Measurement of time to progression may have a greater degree of variability than measurement of best overall response and therefore measurement of minimal selected lesions will lead to a great variability in response assessment.

No significant financial relationships to disclose.

A phase I study evaluating the safety and pharmacokinetics of weekly paclitaxel and carboplatin in relapsed ovarian cancer

This phase I study sought to determine the toxicity profile, pharmacokinetics, and antitumor activity of giving carboplatin every 3 weeks and paclitaxel weekly in patients with relapsed ovarian cancer. Eligible patients with relapsed epithelial ovarian cancer and prior treatment with platinum- and paclitaxel-based therapy were treated with an escalating regimen of carboplatin (day 1) at an area under the curve (AUC) of 4–6 and 1-h infusions of paclitaxel (days 1, 8, and 15) at 50–80 mg/m2 cycled at 3-week intervals. Pharmacokinetic studies were performed on the first day of cycles 1 and 2. All patients had a platinum-free interval of greater than 6 months from the most recent platinum treatment. A total of 77 cycles were administered to 16 patients, with a similar median number of cycles per patient at each dose level varying from 4.6 to 5.3. Febrile neutropenia and grade 4 thrombocytopenia were the dose-limiting toxicities at dose levels 3 and 4 after the third cycle, with no mucositis, nausea, vomiting, or peripheral neuropathy observed greater than grade 2. The maximum tolerated dose of carboplatin was an AUC of 5 and 80 mg/m2 for paclitaxel. Pharmacokinetic analysis showed a marginal statistical difference with regard to reduced systemic paclitaxel concentration after cycle 2 compared with cycle 1 (P= 0.06). Of nine patients evaluable for a radiographic response, the response rate was 66.6% with a complete response of 33.3%. All five patients with nonmeasurable disease achieved a biochemical response. The combination of carboplatin given every 3 weeks at an AUC of 5 and 1-h weekly paclitaxel at 80 mg/m2 is a feasible and reasonably well-tolerated regimen and may have significant antitumor activity in relapsed ovarian cancer patients.

Prospective, blinded comparison of helical CT and CT arterial portography in the assessment of hepatic metastasis from colorectal carcinoma

OBJECTIVE

This prospective blinded comparison of helical CT and helical CT arterial portography aimed to detect liver metastasis from colorectal carcinoma.

METHODS AND MATERIALS

50 patients with colorectal carcinoma were evaluated comparing helical CT with helical CT arterial portography. Each imaging study was evaluated on a 5-point ROC scale by radiologists blinded to the other imaging findings, and the results were compared, with the surgical and pathologic findings as the gold standard.

RESULTS

Of the 127 lesions found at pathology identified as metastatic colorectal cancer, helical CT correctly identified 85 (69%) and CT portography 96 (76%). When subgroups with lesions <3 cm (48 patients) and patients with maximum tumor size <3 cm (18 patients) were considered, CT portography was always better than helical CT in terms of sensitivity, specificity, positive predictive value, and negative predictive value. ROC analysis adjusting for multiple lesions per patient revealed significantly greater area under the curve (AUC) for the subgroup of lesions <3 cm (CT-AUC of 77% and CT portography AUC of 81%; P = 0.002).

CONCLUSIONS

For identification of large metastases, helical CT and CT portography have similar yield. However, for detection of small liver metastases, CT portography remains superior for lesion detectability.

Response to neoadjuvant chemotherapy as measured by PET predicts outcome after liver resection for colorectal metastases

3056

Background: Patients with hepatic colorectal metastases are often treated with neoadjuvant chemotherapy prior to liver resection. FDG PET is a standard imaging modality for such patients. We have shown the amount of FDG uptake in liver metastases is reduced by recent chemotherapy (chemo) administration and this is associated with a reduction in FDG uptake mediated by a reduction in hexokinase activity. We sought to determine if the amount of FDG uptake in the hepatic colorectal metastasis post chemo correlates with survival and to compare the prognostic significance of this single biologic scan to standard clinical predictors of outcome. Methods: A group of 149 patients enrolled in a prospective clinical trial examining the efficacy of FDG PET imaging in patients undergoing hepatic resection of colorectal cancer metastases to the liver formed the dataset. The maximal SUV within the liver was recorded for each patient, and the median of those maximums was determined across the patient group. Patients were then stratified by the median SUV, by the presence or absence of any chemo within 6 months of PET and by the clinical risk score (CRS) (a standard score for prognosis based on five clinical parameter (nodal status of primary, disease-free interval before liver metastases, size of largest liver tumor, number of tumors, and CEA). Multivariate analysis (MVA) and hazard ratios of death (HRD) were assessed. Results: The median of maximal SUVs was 7.9. In MVA in the patients without recent chemo, the CRS≥3 was an excellent predictor of survival (HRD=2.53; p=0.008), while SUV>8 was not (HRD=1.02; p=0.96). Conversely, in patients who had chemo within 6 months, SUV>8 (HRD 3.34; p=0.03) was a much superior predictor of outcome than CRS≥3 (HRD=1.25; p=0.57). Conclusions: In those patients without recent chemo CRS is the best predictor of survival confirming the utility of this scoring system, In those patients who had had chemo within 6 months of PET prior to surgery PET SUV was the best predictor of survival.

No significant financial relationships to disclose.

Prospective trial with preoperative gefitinib to correlate lung cancer response with EGFR exon 19 and 21 mutations and to select patients for adjuvant therapy

7021

Background: Induction therapy provides a unique opportunity for the objective assessment of therapies in patients with NSCLC to facilitate care and advance research. We designed this 40 patient prospective trial to measure gefitinib’s ability to induce regressions preoperatively in individuals with NSCLC and to simultaneously correlate response with mutations in EGFR exons 19 and 21. Patients with ‘in-vivo‘ gefitinib sensitivity and/or mutations receive gefitinib postoperatively as well. To facilitate our goals, we enriched the population studied to select individuals with tumors more likely to harbor mutations in EGFR. Methods: At diagnosis, patients with stage I or II NSCLC had baseline chest CT imaging and a core-needle biopsy to detect EGFR mutations. All participants smoked cigarettes ≤ 10 pack years and/or had tumors with bronchioloalveolar features. All received gefitinib 250 mg daily. After 21 days, CT imaging was repeated and resection followed. Surgical specimens were agained assayed for EGFR mutations. Patients with mutation and/or a ≥ 25% regression (WHO) were given gefitinib 250 mg for 2 years. Results: 20 patients enrolled to date. EGFR mutations were detected in both pre and post gefitinib specimens in 4/19 tested (21%). Five of 19 (26%) had a ≥ 25% bidimensional tumor reduction after 3 weeks. Regressions ≥ 25% were seen in 2/4 (50%) with exon 19 and 21 EGFR mutations and 3/15 (20%) with WT EGFR. The other 2 patients with mutations had 11% and 23% tumor regressions. The 6 patients who had either a ≥ 25% lesion reduction and/or mutation received gefitinib postoperatively. No perioperative complications related to gefitinib occurred. All patients are relapse free. Conclusions: In this ongoing trial, 1) Our ‘enrichment strategy‘ resulted in the detection of twice the expected number of EGFR mutations in USA patients with NSCLC. 2) Gefitinib sensitivity can be assessed by CT in 3 weeks. 3) Results of mutation detection were identical in pre- and post-treatment specimens. 4) The rate of response is numerically higher in patients with EGFR mutations in exons 19 and 21. 5) We are using the surgical specimens to elucidate determinants of gefitinib sensitivity in the absence of EGFR mutation. Support: CA05826, CA113653.

[Table: see text]

Whose information is it anyway? Informing a 12-year-old patient of her terminal prognosis

OBJECTIVE

To examine students' attitudes and potential behaviour towards informing a 12-year-old patient of her terminal prognosis in a situation in which her parents do not wish her to be told, as they pass through a modern medical curriculum.

DESIGN

A cohort study of students entering Glasgow University's new medical curriculum in October 1996.

METHODS

Students' responses obtained before year 1 and at the end of years 1, 3, and 5 to the "childhood leukaemia" vignette of the Ethics in Health Care Survey Instrument (EHCI) were examined quantitatively and qualitatively. Analysis of the students' multichoice answers enabled measurement of the movement towards professional consensus opinion. An analysis of their written justifications for their answers helped to determine whether their reasoning was consistent with professional consensus and enabled measurement of changes in knowledge content and recognition of the values inherent in the vignette. Themes on the students' reasoning behind their decision to tell the patient or not were also identified.

RESULTS

Unlike other vignettes of the EHCI in which autonomy was a main theme, few students chose the consensus answer before year 1 and there was no significant movement towards consensus at any point during the course. In defence of their decision to withhold information, the students expressed strong paternalistic opinions. The patient's age was seen as a barrier to respecting her autonomy.

CONCLUSIONS

It is important to identify students' perceptions on entry to medical school. Transformative learning theory may provide the basis for an approach to foster doctors who consider the rights of young people. Small-group teaching is most conducive to this approach. The importance of positive role modelling is also emphasised.

Rationing decisions: from diversity to consensus

As rationing decisions become more of an immediate reality for healthcare practitioners it is important to design mechanisms that facilitate carefully deliberated outcomes. No individual can be expected to be able to cover wide debate on their own, so an exercise has been designed that helps generate consensus decisions from diverse opinions. The exercise was piloted with two groups, an undergraduate medical class and the members of a general practice. Though the aims were different for each group, the tool was useful to both for producing the desired outcomes. Expert and non-expert knowledge were drawn upon and rationing prioritisation lists regarding funding of infertility treatment were generated. A description of the exercise and the results produced by the two groups are provided, as well as the theoretical placement for the significance of forming consensus from diversity.

[Congenital methemoglobinemia: a rare case of cyanosis in the newborn]

We report the case of a newborn presenting a cyanosis after the birth with a good general state. Congenital methemoglobinemia is a rare disease which is characterized by a brutal appearance, in early infancy, of a bluish skin color not regressing with oxygen inspiration, and by a good general state. It is due to the recessive autosomal NADH-cytochrome b5 reductase (EC. 1.6.2.2) deficiency. This enzyme normally allows the reduction of the physiologically formed methemoglobinemia. Two forms of congenital methemoglobinemia have to be distinguished: the benign form (type I) and the severe form (type II).

Sex and the surgery: students' attitudes and potential behaviour as they pass through a modern medical curriculum

OBJECTIVE

To examine students' attitudes and potential behaviour to a possible intimate relationship with a patient as they pass through a modern medical curriculum.

DESIGN

A cohort study of students entering Glasgow University's new learner centred, integrated medical curriculum in October 1996.

METHODS

Students' pre year 1 and post year 1, post year 3, and post year 5 responses to the "attractive patient" vignette of the Ethics in Health Care Survey instrument were examined quantitatively and qualitatively. Analysis of students' multi-choice answers enabled measurement of the movement towards professional consensus opinion. Analysis of written justifications helped determine whether their reasoning was consistent with professional consensus and enabled measurement of change in knowledge content and recognition of the values inherent in the vignette. Themes on students' reasoning behind their decision to enter a relationship or not were also identified.

RESULTS

No significant movement towards consensus was found at any point in the curriculum. There was little improvement in students' performance in terms of knowledge content and their abilities to recognise the values inherent in the vignette. In deciding to enter a relationship with the patient the most frequently used reasoning was that it could be justified if the patient changed their doctor.

CONCLUSIONS

Teaching on the subject of sexual or improper relationships between doctors and patients, including relationships with former patients requires to be made explicit. Case based teaching would fit in with the ethos of the problem based, integrated medical curriculum.

Students' attitudes and potential behaviour to a competent patient's request for withdrawal of treatment as they pass through a modern medical curriculum

OBJECTIVE

To examine students' attitudes and potential behaviour to a competent patient's request for withdrawal of treatment as they pass through a modern medical curriculum.

DESIGN

Cohort design.

SETTING

University of Glasgow Medical School, United Kingdom.

SUBJECTS

A cohort of students entering Glasgow University's new learner centred, integrated medical curriculum in October 1996.

METHODS

Students' responses before and after year 1, after year 3, and after year 5 to the assisted suicide vignette of the Ethics in Health Care Survey instrument, were examined quantitatively and qualitatively. Analysis of students' multichoice answers enabled measurement of the movement towards professional consensus opinion. Analysis of written justifications helped determine whether their reasoning was consistent with professional consensus and enabled measurement of change in knowledge content and recognition of the values inherent in the vignette. Themes on students' reasoning behind their decision to withdraw treatment or not were also identified.

RESULTS

Students' answers were found to be consistent with professional consensus opinion precurriculum and remained so throughout the curriculum. There was an improvement in the knowledge content of the written responses following the first year of the curriculum, which was sustained postcurriculum. However, students were found to analyse the section mainly in terms of autonomy, with few responses considering the other main ethical principles or the wider ethical perspective. Students were unclear on their legal responsibilities.

CONCLUSIONS

Students should be encouraged to consider all relevant ethical principles and the wider ethical perspective when deliberating ethical dilemmas. Students should have a clear understanding of their legal responsibilities.

Cancer death statistics: analogy between epidemiology and critical systems in physics

The determination of risk factors in carcinogenesis is said to be an essential step towards the understanding of this disease. Most mathematical models describing the evolution of mortality figures use the concept of death probability (or "force of mortality" or "hazard of death"). When summarizing the death statistics through this unique parameter, one implicitly makes the assumption that the death events are independent from one individual to another. In this paper, we show that this hypothesis has profound consequences as it implies a "gaussian" behavior of the death statistics fluctuations. In order to verify the validity of this assumption, French cancer death statistics between the years 1978-1996 are examined. Their fluctuations, for every age bracket, are computed and then compared to the expected gaussian fluctuations that should emerge from a model of death probability. We show that the observed fluctuations are in close agreement with a gaussian model up to 35-40 years. After 40 years, the fluctuations are much higher and cannot be explained by a model where every individual would have a given "probability of death". These observations may produce a new insight into old-age cancer mortality. It suggests that there could exist a major difference between cancers in young or older organisms: cancer developed in young organisms are the consequence of a specific attack against an organ (essentially originated from a single cause, like a virus or a genetic deficiency). On the other hand, older organism are closer to a "critical state" and, as such, the outcome of a cancer in a given organ could be the consequence of a chain of "malfunctions" (analogous to an avalanche in physical systems) in the entire organism.

Human recombinant DNA-derived antihemophilic factor in the treatment of previously untreated patients with hemophilia A: final report on a hallmark clinical investigation

BACKGROUND

Development of recombinant factor VIII (rFVIII) replacement therapy represents a milestone in the treatment of hemophilia A.

OBJECTIVE

The objective of this long-term, multicenter study was to assess the safety, efficacy and rate of inhibitor formation of rFVIII (Kogenate) in the treatment of hemophilia A in a group of previously untreated patients (PUPs).

PATIENTS AND METHODS

Between January 1989 and October 1997, 102 evaluable patients (mean age 3.9 years) were treated with rFVIII as sole therapy for prophylaxis against bleeding or for hemorrhage. Patients with mild hemophilia were treated for > or =2 years, while those with moderate or severe hemophilia were treated for > or =5 years or 100 exposure days.

RESULTS

All patients responded well to therapy, so that 82% of bleeding episodes required a single infusion for treatment. Only four mild drug-related adverse events were recorded during the study for an overall rate of 0.03% (4/13 464 infusions). No viral seroconversions were observed. The inhibitor incidence in PUPs with severe hemophilia was 29% (19/65). Overall, inhibitory antibodies developed in 21 patients (20.6%). Inhibitor titers were low (<10 Bethesda Units) in nine of the 21 patients despite continued episodic treatment with rFVIII and transient in eight patients receiving episodic treatment (seven low titer, one high titer). Eight high-titer inhibitor patients were treated with immune-tolerance induction therapy; five had successful outcomes.

CONCLUSIONS

The observed incidence of inhibitor formation is similar to studies of PUPs receiving plasma-derived FVIII. These results demonstrate the safety and efficacy of rFVIII in long-term treatment of hemophilia A.

Parallel experience: how art and art theory can inform ethics in human research

Trends in ethical research involving humans emphasise the importance of collaboration, of involving research subjects, alongside the researchers in the construction and implementation of research. This paper will explore parallels derived from another tradition of investigation of the human: art and art theory. An artist's inquiry into the problems of human research will be described, followed by the application of arguments from art theory to research practice. Recently artist Christine Borland has provided examples in which the lack of collaboration in research has caused injustice. Borland's work reflects these ethical dilemmas and questions the procedures and assumptions involved. In most cases the value of subject anonymity is called into question because it reduces the subjects' control over themselves. The application of art theory, which has already considered these problems, helps question and explore the ways in which the subject turned object of artistic or scientific interpretation can maintain some control and dignity.

Pilot study of epothilone B analog (BMS-247550) and estramustine phosphate in patients with progressive metastatic prostate cancer following castration

BACKGROUND

Several trials have demonstrated that the response proportions to microtubule agents in patients with prostate cancer are increased by the addition of estramustine phosphate (EMP). The epothilone B analog BMS-247550 is a novel microtubule agent that has shown activity in taxane-resistant tumors. We conducted a dose-escalation study to determine a safe dose of BMS-247550 to combine with EMP in patients with metastatic prostate cancer.

PATIENTS AND METHODS

Chemotherapy-naive patients with castrate-metastatic prostate cancer were treated with intravenous BMS-247550 and oral EMP (280 mg three times daily for 5 days) every 3 weeks.

RESULTS

Thirteen patients were treated at two dose levels (35 and 40 mg/m(2)). Three of six patients treated at 40 mg/m(2) developed grade 4 neutropenia, establishing 35 mg/m(2) as the maximum-tolerated dose. Significant peripheral neuropathy (grade >/= 2) was related to dose level and infusion rate. A decline in prostate-specific antigen (PSA) of >/= 50% was seen in 11 of 12 evaluable patients (92%) (95% confidence interval 76% to 100%). There were objective responses in soft tissue (57%) and bone metastasis (40%).

CONCLUSIONS

The phase II dose of BMS-247550 combined with EMP is 35 mg/m(2) over 3 h every 3 weeks. This combination is safe and >/= 50% post-therapy declines in PSA were seen in 11 of 12 patients (92%).

Growth and cellular differentiation: a physico-biochemical conundrum? The example of the hand

Currently, the predominant hypothesis explains cellular differentiation as an essentially genetic intracellular process. The goal of this paper is to suggest that cell growth and differentiation may be, simply, the result of physical and chemical constraints. Bone growth occurs at the level of cartilage conjunction (growth plate) in a zone of lesser constrain. It appears that this growth also induces muscle, tendon, nerve and skin elongation. This cartilage growth by itself seems to explain the elongation of the hand. Growth stops at puberty likely because of feed-back from an increasing muscle load. The ossification (that is differentiation of cartilage into bone) appears to result from the shear stress induced. The study of bone age, obtained by X-ray picture of the hand, shows that ossification of epiphyses is very precise both in time and space. Computer modelization suggests that this ossification occurs where shear stress is greatest. The cartilage which does not ossify (joint, nose, larynx, ear, bronchus, etc.) is not exposed to high shear. Shear stress induces the secretion of extracellular matrix and a change of the biochemical environment of the cell. Precipitation of calcium phosphate, as in ossification, seems related to the alkalosis induced by shear stress. To speak in more general terms, loss of cellular differentiation, as occurs with cancer, can result from a change in the physical-chemical environments.

Blue light dose distribution and retinitis pigmentosa visual field defects: an hypothesis

The hypothesis that retinitis pigmentosa (RP) is worsened by blue light has been raised a century ago. In order to check this hypothesis we calculated the theoretical dose distribution of light on the retinal surface. The relative dose to the different parts of the retina was calculated using a Monte-Carlo method. The changes in the peripheral isopters were calculated both degrading at a constant rate and degrading proportionally to light exposure. There is a considerably greater exposure to the superior compared to the inferior visual field. The maximum dose of UV and blue light is located on the superior field about 4mm above the macula. The dose received by the peripheral retina is markedly lower than the dose received by the central retina. The visual field defects most commonly described in RP are concentric, centered by the macula. These defects cannot, therefore, be explained by the impact of light on the retina. But some regional form of RP with a superior field defect can result from an abnormal genetically encoded sensitivity to ultraviolet and blue light.

Cancer: the role of extracellular disease

Invasive carcinoma originates from the epithelial cells lining the lumen of an organ. It is often preceded by metaplasia, dysplasia or carcinoma in situ. The purpose of this review is to suggest that this disease of the epithelium may be, in part, the result of underlying tissue-based disorganization. Human cancer is frequently associated with pre-existing tissue disease. For example, hepatocellular carcinoma usually occurs in patients with a macronodular cirrhotic liver. Most lung cancers arise among patients with chronic lung disease (bronchitis, emphysema, and chronic infection). Mechanical forces appear to play a major role in regulating normal and cancer cell growth. The loss of cell polarity by neoplastic cells, coupled to an otherwise normal growth rate is enough to explain the cancer star-shaped pattern. By changing the plane of cell division, tumor cells may escape physical constraints from surrounding cells and divide. Loss of cell polarity and the resulting cell proliferation appears to be a consequence of either tissue-based disorganization (chronic inflammation, fibrosis) or of direct carcinogenic insult. The multiple mutations frequently described in cancer may be, in part, secondary to physical stress and not primary events. Several animal and clinical trials have shown that tissue disruption (i.e. radiation-induced fibrosis or liver cirrhosis) can be successfully treated. It is possible that treatment targeted at tissue disruption would delay or reduce cancer incidence regardless of the precise biological mechanism of carcinogenesis.

Phase II trial of irofulven (6-hydroxymethylacylfulvene) for patients with advanced renal cell carcinoma

The aim of this study was to determine the antitumor activity of irofulven (6-hydroxymethylacylfulvene) in patients with advanced renal cell carcinoma (RCC). Eligible patients had advanced renal cell carcinoma with bidimensionally measurable disease, a Karnofsky performance status of at least 70, life expectancy of greater than three months, no prior treatment with chemotherapy, and no evidence of brain metastases. Irofulven was administered at a dose of 11 mg/m2 by 5-min intravenous infusion, on 5 consecutive days. Cycles were repeated every 28 days. Thirteen patients were enrolled in this study and 12 were evaluable for response. Of the twelve evaluable patients, no major responses were achieved. Eight patients had stable disease as best response. Toxicity included myelosuppression and gastrointestinal side effects. At the dose and schedule used in this trial, irofulven did not produce clinical response in RCC.

Is there an advocate in the house? The role of health care professionals in patient advocacy

It remains unclear what patient advocacy actually entails and what values it ought to embody. It will be useful to ascertain whether advocacy means supporting any decision the patient makes, or if the advocate can claim to represent the patient by asserting well-intentioned paternalistic claims on the patient's behalf. This is especially significant because the position of advocate brings with it certain privileges on the basis of of presumed insight into patient-perceived interests, namely, entitlement to take part in clinical decision making and increased professional standing. Three issues related to patient advocacy will be explored: are patient advocates necessary; what does advocacy entail, and who ought to represent patients in this way-arguments for and against prospective candidates will also be covered. The paper considers whether advocates are necessary since not only can they be dangerously paternalistic, but the salutary values advocacy embodies are already part of good professional health care.

The application of telemedicine technology to a directly observed therapy program for tuberculosis: a pilot project

We evaluated the use of videophone technology to provide directly observed therapy (DOT) to patients with active tuberculosis. During 304 treatment doses, adherence on videophone DOT was 95%, and patient acceptance of the technology was excellent. In selected cases, the use of videophone technology can maintain a high level of adherence to DOT in a cost-effective manner.

Shared patient analysis: a method to assess the clinical benefits of patient referrals

BACKGROUND

Referral to specialized physicians or institutions often is deemed necessary in clinical medicine, but no method exists to assess the clinical benefit of such referrals.

OBJECTIVES

To describe a method, which is shared patient analysis, to measure the expected improvement in clinical management associated with referrals and to apply that method in the field of abdominal and pelvic oncological radiology.

SUBJECTS

All patients referred, during a 4-year period, to surgical oncologists at four academic centers (the referral providers, or RPs) with radiographs performed before referral at a community site (the initial providers, or IPs). Patients (n = 396) for whom both the IP interpretation and a final diagnosis was available were eligible. All IP and RP readings were placed in random order and presented to surgical oncologists, who then recommended a treatment course.

MEASUREMENTS

Diagnostic accuracy of the IP and RP readings and the proportion of patients who were assigned to an appropriate treatment by the oncologist were determined.

RESULTS

When the indication for imaging was primary diagnosis or staging, the kappa for presence of cancer was 0.70. When the indication was cancer follow-up, the kappa for presence of recurrent/progressing cancer was 0.66. There were disagreements between the IP and RP radiologists over the interpretation of 162 films, with the RP radiologists being correct in 153 (94%). Had the patients been treated using IP readings, there would have been 19 more inappropriate surgeries and 19 more admissions (both P <0.05) than if the oncologists had based their recommendations on RP readings.

CONCLUSIONS

The technique of shared patient analysis permits assessment of the clinical benefits associated with referrals.

[Survival in adolescents and young adults with cancer in childhood]

A group of 104 long-term survivors of childhood cancer have been studied at the Oncology Unit of the Children's Hospital of Buenos Aires. The tumors were diagnosed and treated between 1965 and 1986 and evaluated until December 1999. The diagnosis were: retinoblastoma: 24, nephroblastoma: 19, Hodgkin's disease: 14, sarcoma: 12, neuroblastoma: 11, non-Hodgkin-lymphoma: 11, Langerhans cell histiocytosis: 5 (multifocal bone lesions: 4, Hand-Schüller-Christian disease: 1), gonadal germ-cell tumors: 4, osteosarcoma: 2, Ewing sarcoma: 2. The treatment consisted of: surgery + chemotherapy + radiotherapy: 52, chemotherapy + radiotherapy: 18, surgery + chemotherapy: 13, surgery + radiotherapy: 7 surgery: 7 and chemotherapy: 7. A total of 101 survivors are alive without evidence of cancer between 15 and 44 years of age. Four of them suffered serious late effects threatening their lives: cardiac insufficiency: 2, renal insufficiency: 1 and panhypopituitarism: 1 (this patient died). Out of 5 patients with a second cancer, the follow-up was lost in 2. In 51 survivors education data were available and in 27 their laboral situation. Nine young women were mothers and five young men were fathers. It is concluded that a constant follow-up and evaluation of these patients is necessary in order to give them the opportunity of therapeutic solutions and psychosocial rehabilitations.

Endometrial stromal sarcoma: objective response to letrozole

BACKGROUND

Low-grade endometrial stromal sarcoma is generally an indolent tumor rich in estrogen and progesterone receptors. Objective responses to hormonal therapy, most commonly with megestrol acetate, have been reported.

CASE

The patient is a 51-year-old woman who presented with low-grade endometrial stromal sarcoma confined to the uterus in 1991 and was treated with total abdominal hysterectomy and bilateral salpingo-oophorectomy. Approximately 5 years later, the patient had recurrent pelvic disease treated with radiation therapy, followed by an attempt at resection. She was treated with megestrol acetate during the period she received radiation therapy with poor tolerance. Tamoxifen was then given with no tumor response. Megestrol acetate was restarted with progression of disease in the pelvis and abdomen. Letrozole was then given at a daily dose of 2.5 mg with partial response for a duration of 9 months.

CONCLUSION

Letrozole at a daily dose of 2.5 mg may be effective in low-grade endometrial stromal sarcoma with positive estrogen receptors.

The effect of surfactant on birthweight-specific neonatal mortality rate, New York City

PURPOSE

Surfactant has been shown to cause decreased neonatal mortality rate (NMR) in randomized studies of preterm infants. It is not clear whether the introduction of surfactant caused a decrease in neonatal mortality in a community. This study explores the hypothesis that the introduction of surfactant in 1990 to 1991 explains a decrease in neonatal mortality in New York City (NYC) among infants with birthweight of 500 to 1499 g.

METHODS

For each of the 20 hospitals in New York City that began using surfactant in 1990 or 1991, we compared the NMR in the 2 years before the introduction of surfactant with the NMR in the 2 years after its introduction. Poisson regression models were fit to the death rates, adjusting for birthweight and other determinants of neonatal mortality.

RESULTS

NMR in the 20 hospitals decreased by 13.7% (from 231.3 to 199.6 neonatal deaths per 1000 live births). This decrease remained significant after adjusting for birthweight and other risk factors. Infants with birthweight 1000 to 1249 grams benefited most from the introduction of surfactant; their NMR decreased by 19.6%. After adjusting for birthweight, those born before the introduction of surfactant were 1.18 times as likely to die in the first 27 days as those born after the introduction of surfactant (95% CI 1.04, 1.33).

CONCLUSION

It appears that surfactant had a significant impact on NMR in NYC among very low birthweight babies.

Phase I Study of Hepatic Arterial Infusion of Floxuridine and Dexamethasone With Systemic Irinotecan for Unresectable Hepatic Metastases From Colorectal Cancer

PURPOSE: To determine the maximum-tolerated dose (MTD) and dose-limiting toxicities of concurrent systemic irinotecan and hepatic arterial infusion (HAI) of floxuridine (FUDR) and dexamethasone in patients with unresectable hepatic metastases from colorectal cancer, to determine the safety of this combination in patients who have undergone cryosurgery, and to evaluate the pharmacokinetic effects of HAI FUDR on the metabolism of irinotecan.

PATIENTS AND METHODS: Forty-six previously treated patients with unresectable liver metastases and no known extrahepatic disease were treated concurrently with intravenous irinotecan weekly for 3 weeks and with HAI of FUDR and dexamethasone for 14 days (both were recycled in 28 days). Parallel cohorts of patients treated with or without cryosurgery were entered at escalating dose levels.

RESULTS: The MTD for patients who did not undergo cryosurgery was 100 mg/m2 of irinotecan weekly for 3 weeks every 4 weeks with concurrent HAI FUDR (0.16 mg/kg/d × pump volume/flow rate) plus dexamethasone for 14 days of a 28-day cycle. The dose-limiting toxicities were diarrhea and neutropenia. The response rate (complete and partial) among all patients who did not undergo cryosurgery was 74%. All patients in the cryosurgery group responded, and seven of the eight cryosurgery patients developed normal positron emission tomography scans after chemotherapy. HAI FUDR had no effect on the metabolism of irinotecan.

CONCLUSION: Combination therapy with HAI FUDR and dexamethasone plus systemic irinotecan may be safely administered to patients with unresectable hepatic metastases from colorectal cancer. The MTD has been reached for patients with unresectable disease, and we continue to investigate the MTD for patients who have undergone cryosurgery. Although the main objective of this study was to evaluate the toxicity of the combined regimen, a high response rate (74%) was observed.

The Quinapril Ischemic Event Trial (QUIET): evaluation of chronic ace inhibitor therapy in patients with ischemic heart disease and preserved left ventricular function

Angiotensin-converting enzyme inhibitors improve endothelial function, inhibit experimental atherogenesis, and decrease ischemic events. The Quinapril Ischemic Event Trial was designed to test the hypothesis that quinapril 20 mg/day would reduce ischemic events (the occurrence of cardiac death, resuscitated cardiac arrest, nonfatal myocardial infarction, coronary artery bypass grafting, coronary angioplasty, or hospitalization for angina pectoris) and the angiographic progression of coronary artery disease in patients without systolic left ventricular dysfunction. A total of 1,750 patients were randomized to quinapril 20 mg/day or placebo and followed a mean of 27 +/- 0.3 months. The 38% incidence of ischemic events was similar for both groups (RR 1.04; 95% confidence interval 0.89 to 1.22; p = 0.6). There was also no significant difference in the incidence of patients having angiographic progression of coronary disease (p = 0.71). The rate of development of new coronary lesions was also similar in both groups (p = 0.35). However, there was a difference in the incidence of angioplasty for new (previously unintervened) vessels (p = 0.018). Quinapril was well tolerated in patients after angioplasty with normal left ventricular function. Quinapril 20 mg did not significantly affect the overall frequency of clinical outcomes or the progression of coronary atherosclerosis. However, the absence of the demonstrable effect of quinapril may be due to several limitations in study design.

Craniofacial, temporal bone, and audiologic abnormalities in the spectrum of hemifacial microsomia

OBJECTIVES

To evaluate the clinical, audiologic, and temporal bone computed tomograpic findings in patients with hemifacial microsomia and to use the OMENS (each letter of the acronym indicates 1 of the following 5 dysmorphic manifestations: O, orbital asymmetry; M, mandibular hypoplasia; E, auricular deformity; N, nerve involvement; and S, soft tissue deficiency) grading system to assess possible correlations between the severity of dysmorphic features with the type of abnormalities in the temporal bone and with degree of hearing deficit.

DESIGN

Retrospective study.

SETTING

Tertiary care children's hospital.

PATIENT

Forty patients with hemifacial microsomia.

RESULT

Mandibular hypoplasia and auricular abnormalities were the most common clinical manifestations, present in 39 patients (97%) and 38 patients (95%), respectively. Conductive hearing loss was noted in 35 patients (86%) and sensorineural hearing loss in 4 patients (10%). Facial nerve weakness was present in 20 patients (50%). Twenty patients had unilateral aural atresia, 12 patients had unilateral aural stenosis, and 7 patients had bilateral anomalies. Moderate hypoplasia or atresia of the middle ear was noted in 36 patients (90%) and ossicles were malformed in 30 patients (75%). Hypoplasia of the oval window was the most common inner ear abnormality.

CONCLUSIONS

Severity of craniofacial features (total OMENS score) significantly correlated with the degree of temporal bone abnormality, but no correlation was noted with the degree or type of hearing loss. We recommend the following: (1) use of the OMENS classification system for documentation and analysis of dysmorphic finding in hemifacial microsomia; (2) complete audiologic evaluation in all patients with hemifacial microsomia regardless of the type of craniofacial abnormalities; and (3) temporal bone computed tomography for further evaluation of hearing deficit.

Impact of a new course on students' potential behaviour on encountering ethical dilemmas

OBJECTIVE

To evaluate the effectiveness of small-group ethics teaching in an integrated medical curriculum.

DESIGN

A quasi-experimental, pre- and post-test, non-equivalent control group design.

SETTING

University of Glasgow Medical School.

SUBJECTS

111 first-year students from Glasgow University's new learner-centred medical curriculum, with a control group of 51 students from the last year of the traditional curriculum.

MAIN OUTCOME MEASURE

Student answers consistent with consensus professional judgement on the ethical dilemmas posed by the vignettes of the Ethics and Health Care Survey Instrument.

RESULTS

There was a significantly greater increase in the number of post-test consensus answers in the experimental group (P=0.0048): the odds ratio for obtaining the post-test consensus answer in the experimental group compared with the control group was 1.73 (95% confidence interval 1.28-2.33). Significant movement towards consensus occurred in the areas of autonomy, confidentiality and consent. Among controls there was a significant move away from consensus in the area of "whistle blowing" on colleagues (P=0.017).

CONCLUSION

Small-group ethics teaching, in an integrated medical curriculum, had a positive impact on the first-year students' potential ethical behaviour. It was more effective than a lecture and a large-group seminar-based course in developing students' normative identification with the profession of medicine.

Paclitaxel, estramustine phosphate, and carboplatin in patients with advanced prostate cancer

PURPOSE

To determine the safety and activity of weekly paclitaxel in combination with estramustine and carboplatin (TEC) in patients with advanced prostate cancer.

PATIENTS AND METHODS

In a dose-escalation study, patients with advanced prostate cancer were administered paclitaxel (weekly 1-hour infusions of 60 to 100 mg/m(2)), oral estramustine (10 mg/kg), and carboplatin (area under the curve, 6 mg/mL-min every 4 weeks). Paclitaxel levels were determined 0, 30, 60, 90, and 120 minutes and 18 hours after infusion, and a concentration-time curve was estimated. Once a safe dose was established, a multi-institutional phase II trial was conducted in patients with progressive androgen-independent disease.

RESULTS

Fifty-six patients with progressive androgen-independent disease were treated for a median of four cycles. The dose of paclitaxel was escalated from 60 to 100 mg/m(2) without the occurrence of DLT. Posttherapy decreases in serum prostate-specific antigen levels of 50%, 80%, and 90% were seen in 67%, 48%, and 39% (95% confidence interval, 55% to 79%, 35% to 61%, 26% to 52%) of the patients, respectively. Of the 33 patients with measurable disease, two (6%) had a complete response and 13 (39%) had a partial response. The overall median time to progression was 21 weeks, and the median survival time for all patients was 19.9 months. Major grade 3 or 4 adverse effects were thromboembolic disease (in 25% of patients), hyperglycemia (in 38%), and hypophosphatemia (in 42%). Significant leukopenia, thrombocytopenia, and peripheral neuropathy were not observed.

CONCLUSION

TEC has significant antitumor activity and is well tolerated in patients with progressive androgen-independent prostate cancer.

Results of the BRAT study--a pilot study investigating the possible significance of ASA nonresponsiveness on the benefits and risks of ASA on thrombosis in patients undergoing coronary artery bypass surgery

BACKGROUND

Several studies suggest that acetylsalicylic acid (ASA) is less effective in preventing thrombotic events in ASA nonresponder patients. If so, the thrombotic event rate in ASA nonresponders should be higher than in ASA responders.

OBJECTIVE

To conduct a prospective, multicentre observational pilot study to determine the thrombotic event rates in ASA responders and nonresponders.

PATIENTS AND METHODS

Patients undergoing nonurgent coronary artery bypass grafting (CABG) who were prescribed 325 mg ASA/day were recruited. Patients were classified as an ASA responder or nonresponder based on the ASA effect (or lack thereof) on their bleeding times. All thrombotic events that occurred in the two years following CABG were recorded. These data were stored in a blinded fashion until the last patient follow-up, and then adjudicated by a validation committee.

RESULTS

A total of 289 patients recruited at three sites completed the two-year follow-up. Of these patients, 45.3% were classified as ASA responders and 54.7% were classified as ASA nonresponders. Of ASA responders, 6.9% had thrombotic events compared with 9.5% of the ASA nonresponders, but this difference was not significant (P=0.526).

CONCLUSIONS

While ASA responder or nonresponder status did not appear to affect the thrombotic event rate in patients undergoing nonurgent CABG, the possibility that ASA responder or nonresponder status affects the thrombotic event rate in more acutely ill CABG patients cannot be excluded.

Posttransplantation hypertension related to calcineurin inhibitors

Calcineurin inhibitors are a mainstay of transplant immunosuppression and commonly induce hypertension. They are highly lipid soluble and penetrate vascular smooth muscle cell membranes readily. Changes in vascular tone are universally observed during administration of these agents, particularly within the kidney, leading to diminished glomerular filtration and enhanced sodium retention. Disturbances of endothelial function are prevalent in many tissues, including stimulation of endothelin and impaired nitric oxide synthesis. Multiple additional pathways produce increased vasoconstriction, leading to an increase in arterial pressure. Clinical manifestations include disturbances in circadian blood pressure patterns, left ventricular hypertrophy, and acceleration of atherosclerotic and renal injury. Rapid increases in pressure occasionally produce accelerated hypertension and microangiopathic tissue damage. Principles of therapy require recognition of hazards of changing arterial pressures during calcineurin use and preferential use of vasodilating drugs, particularly dihydropyridine calcium channel blocking agents. Attention must be paid to interactions between antihypertensive agents and calcineurin inhibitor blood levels.

Intraoperative conformal optimization for transperineal prostate implantation using magnetic resonance spectroscopic imaging

PURPOSE

Recent studies have demonstrated that magnetic resonance spectroscopic imaging (MRSI) of the prostate may effectively distinguish between regions of cancer and normal prostatic epithelium. This diagnostic imaging tool takes advantage of the increased choline and creatine versus citrate ratio found in malignant, compared with normal, prostate tissue. The purpose of this report is to present our initial experience integrating MRSI data into an intraoperative computer-based optimization planning system for prostate cancer patients who underwent permanent interstitial I 125 implantation. The goal of this approach was to achieve dose escalation to intraprostatic tumor deposits on the basis of MRSI findings without exceeding the tolerance of adjacent normal tissue structures.

MATERIALS AND METHODS

MRSI was obtained before surgery for four consecutive patients with clinically localized prostate cancer. The ratios of choline and citrate for the prostate were analyzed, and regions in which malignant cells were suspected to be present were identified. These ratios were calculated on a spatial grid overlying the axial MRSI of the prostate. MRSI coordinates containing these suspicious regions were registered to the intraoperative ultrasound images. A computer-based treatment planning system, which relied on a genetic algorithm, was used to determine the optimal seed distribution necessary to achieve maximal target volume coverage with the prescription dose and to maintain urethra and rectal doses within tolerance ranges. The treatment planning system was specifically designed to escalate the dose to MRS-positive voxels while at the same time achieving preferential sparing of surrounding normal tissues. Patients underwent transperineal interstitial implantation with I 125 by use of this intraoperatively generated plan. Postimplant computed tomographic scans were performed on the same day of the procedure in all cases, and dosimetric guidelines of the American Brachytherapy Society were used to assess implant quality.

RESULTS

Based on the postimplant computed tomographic evaluation, the intraoperative optimization treatment planning program was able to achieve a minimum dose of 139% to 192% of the 144-Gy prescription dose to the MRS-positive voxels. The percentage of the prostate volume receiving 100% of the prescription dose ranged from 92% to 97%, and the dose delivered to 90% of the target for the target volume ranged from 96% to 124%. Despite the dose escalation achieved for the positive voxels, the urethral and rectal doses were maintained within tolerance ranges. The average and maximal rectal doses ranged from 28% to 43% and 69% to 115% of the prescription dose, respectively. The average and maximal urethral doses ranged from 66% to 144% and 118% to 166% of the prescription dose, respectively.

CONCLUSIONS

Using this brachytherapy optimization system, we could demonstrate the feasibility of MRS-optimized dose distributions for I 125 permanent prostate implants. This approach may have an impact on the ability to select regions within the prostate to safely employ dose escalation for patients treated with permanent interstitial implantation and to improve outcome for patients with organ-confined prostatic cancers.

A process evaluation of medical ethics education in the first year of a new medical curriculum

BACKGROUND

Despite the recent increase in activity in the field of medical ethics education, few evaluative studies have been carried out. Most studies have taken place in North America, in curricula where teaching is discipline-based, and have concentrated on outcome rather than on the curricular processes adopted.

AIM

To evaluate the process of medical ethics education in the first year of a new learner-centred, problem-based, integrated medical curriculum.

METHOD

A qualitative, multi-method approach was adopted using open questionnaires, focus groups and tutor evaluation rating scales. The study involved all 238 students in the first year of the new medical curriculum, and the 30 clinical tutors who facilitated ethics learning. A stratified sampling technique was used to choose focus group participants.

RESULTS

Small group teaching proved highly acceptable to both students and tutors. Tutors' teaching skills were central to its effectiveness. Tutors played an important role in promoting students' appreciation of the relevance of medical ethics to clinical practice, and in establishing a climate where constructive criticism of colleagues' actions is acceptable. Course integration, including the provision for students of clinical experiences on which to reflect, was an important aid to learning. Students and tutors were noted to be driving the ethics curriculum towards having a contextual rather than theoretical base.

CONCLUSION

This evaluation identified those aspects of the medical ethics course which contributed to its effectiveness and those which detracted from it. This information will be used to inform future development.

Results of a phase II study using estramustine phosphate and vinblastine in combination with high-dose three-dimensional conformal radiotherapy for patients with locally advanced prostate cancer

PURPOSE

To assess the feasibility and tolerance of neoadjuvant and concomitant estramustine phosphate and vinblastine (EV) with high-dose three-dimensional conformal radiotherapy (3D-CRT) for patients with unfavorable-risk prostate cancer.

PATIENTS AND METHODS

Twenty-seven patients with unfavorable-risk prostate cancer were enrolled onto a prospective study to determine the feasibility of combining EV with 3D-CRT. Patients were eligible if any of the following requirements were satisfied: (1) Gleason score > or =8 and prostate-specific antigen (PSA) > 10 ng/mL; (2) Gleason score of 7 and PSA > 20 ng/mL; (3) clinical stage T3N0M0 disease with PSA > 20 ng/mL; (4) any patient with T4N0M0 disease; or (5) patients with TXN1MO disease. Therapy consisted of three 8-week cycles of EV and 8 weeks of 3D-CRT. Estramustine phosphate was given orally beginning on week 1 and continued until the completion of 3D-CRT. Each 8-week cycle of vinblastine consisted of 6 weekly intravenous injections followed by a 2-week rest period. Radiation therapy was administered using a three-dimensional conformal approach to a prescription dose of 75.6 Gy. The median follow-up was 26 months (range, 6 to 40 months).

RESULTS

Twenty-three (85%) of 27 patients completed the entire course of therapy and were assessable for toxicities and biochemical outcome. Two patients (7%) developed grade 3 hematologic toxicity that resolved, and two patients (7%) developed grade 3 hepatoxicity, manifesting as persistent elevation of serum transaminase levels, necessitating discontinuation of the chemotherapy and withdrawal from the treatment program. The most prominent adverse effects from this regimen were mild to moderate (grade 1 to 2) nausea and fatigue related to estramustine. Mild peripheral edema was seen in 15% of patients and was treated with diuresis. 3D-CRT was tolerated well in these patients. Medications were required for relief of acute grade 2 rectal (gastrointestinal [GI]) and urinary (genitourinary [GU]) symptoms in 35% and 48% of patients, respectively. Three patients developed acute grade 3 GU toxicities. The 2-year actuarial likelihood of late grade 2 GI toxicity was 20%. No late grade 3 or 4 GI toxicities were observed. The 2-year actuarial likelihoods of late grade 2 and 3 GU toxicities were 25% and 12%, respectively. No grade 4 GU toxicity was observed.

CONCLUSION

Neoadjuvant and concomitant EV with high-dose 3D-CRT is well tolerated in patients with unfavorable-risk prostate cancer. Although the incidence of modest (grade 2) late GI and GU toxicities seem to be increased compared with 3D-CRT alone or in combination with androgen ablation therapy, no severe toxicities were encountered with this regimen.

Hypertension after liver transplantation: a predictive role for pretreatment hemodynamics and effects of isradipine on the systemic and renal circulations

Hypertension developing after liver transplantation during immunosuppression with cyclosporine A reflects an unusual hemodynamic transition from peripheral vasodilation to systemic and renal vasoconstriction. Although dihydropyridine calcium channel blockers are often administered for their efficacy in promoting vasodilation, some liver transplant recipients report marked symptomatic intolerance to these agents. In the present study we examined systemic and renal responses to isradipine using systemic (thoracic bioimpedance) and renal hemodynamic measurements in 15 liver transplant recipients studied at the time of initial diagnosis of posttransplant hypertension and after 3 months of treatment. Circadian blood pressure patterns were examined by overnight ambulatory blood pressure monitoring before and during antihypertensive therapy. During isradipine administration, blood pressure decreased from 151 +/- 3/91 +/- 2 to 130 +/-3/81 +/- 2 mm Hg (P < .01) without change in renal blood flow (406 +/- 43 to 425 +/- 52 mL/min/1.73m2, P = NS) or renal vascular resistance index (25,674 +/-3312 to 20,520 +/- 2311 dynes x sec x cm(-5)/m2, P = NS). Pre-treatment differences in systemic vascular tone persisted during treatment and predicted the tendency for symptomatic tachycardia and flushing, predominantly in those with hyperdynamic circulations. Twice daily dosing of isradipine was associated with partial and significant restoration of the nocturnal decrease in blood pressure (systolic blood pressure decreased 5.5%, normal 13%), usually absent early after transplantation. Our results demonstrate the ability of hemodynamic measurements to predict the symptomatic response to antihypertensive therapy in the posttransplant setting.

Effects of spinal cord X-irradiation on the recovery of paraplegic rats

Axonal regrowth is limited in the adult CNS, especially in the spinal cord, one of the major sites of traumatic lesions. Pathophysiological changes occurring after spinal cord injury include complex acute, subacute, and late processes. In this study, we assessed whether X-irradiation interferes with the acute/subacute phases, thereby improving the functional recovery of paraplegic animals. Two days after acute compression of adult rat spinal cords, various doses (0, 2, 5, 10, 20 Gy) of X-rays were administered as one single dose to the compression site. The animals were functionally evaluated over the course of 1 month after injury, using the Tarlov scale and the Rivlin and Tator scale. We also designed a "physiological" scale, including an assessment of urinary function and infection, appropriate for the evaluation of spinal-cord-lesioned animals. Behavioral analysis suggested that the high doses, 20 Gy and, to a lesser extent, 5 and 10 Gy, were toxic, as shown by morbidity rate and "physiological" score. The 2-Gy group showed better motor performances than the lesioned nonirradiated (LNI) animals and the 5- and 20-Gy groups. Motor performance in the 5-, 10-, and 20-Gy groups was poorer than that seen in the LNI group. Gliosis was reduced in the 2-Gy group compared to LNI animals, and there was high levels of gliosis in the highly (>/=5 Gy) irradiated animals. There was a 23% less lesion-induced syringomyelia in the 2-Gy group than in the other groups (LNI and 5-20 Gy). Thus, low doses of X-rays may interfere with the formation of syringomyelia and glial scar, thereby facilitating the recovery of paraplegic animals. These findings suggest that low-dose irradiation of the lesion site, in association with other therapies, is a potentially promising treatment for improving recovery after spinal cord injury.