Tracking of neurocognitive outcomes over time in children with perinatal stroke and associated complex medical conditions: a case series

Neurocognitive outcomes in children with perinatal stroke are complicated by additional neurological/medical factors. The main objective of this study was to retrospectively examine long-term neurocognitive outcomes in five children with perinatal stroke with increasingly complex comorbidities; ages 5-7 at first evaluation. Results revealed that intelligence and academic skills were significantly decreased in cases with combined perinatal stroke and comorbidities. Early language development was particularly vulnerable to disruption over time in children with increasing medical complexity. The delayed emergence of neurocognitive deficits emphasizes the need for serial assessment of neurocognitive development to identify early services and interventions.

Inhibition of cyclo-oxygenase 2 reduces tumor metastasis and inflammatory signaling during blockade of vascular endothelial growth factor

Vascular endothelial growth factor (VEGF) blockade is an effective therapy for human cancer, yet virtually all neoplasms resume primary tumor growth or metastasize during therapy. Mechanisms of progression have been proposed to include genes that control vascular remodeling and are elicited by hypoperfusion, such as the inducible enzyme cyclooxygenase-2 (COX-2). We have previously shown that COX-2 inhibition by the celecoxib analog SC236 attenuates perivascular stromal cell recruitment and tumor growth. We therefore examined the effect of combined SC236 and VEGF blockade, using the metastasizing orthotopic SKNEP1 model of pediatric cancer. Combined treatment perturbed tumor vessel remodeling and macrophage recruitment, but did not further limit primary tumor growth as compared to VEGF blockade alone. However, combining SC236 and VEGF inhibition significantly reduced the incidence of lung metastasis, suggesting a distinct effect on prometastatic mechanisms. We found that SC236 limited tumor cell viability and migration in vitro, with effects enhanced by hypoxia, but did not change tumor proliferation or matrix metalloproteinase expression in vivo. Gene set expression analysis (GSEA) indicated that the addition of SC236 to VEGF inhibition significantly reduced expression of gene sets linked to macrophage mobilization. Perivascular recruitment of macrophages induced by VEGF blockade was disrupted in tumors treated with combined VEGF- and COX-2-inhibition. Collectively, these findings suggest that during VEGF blockade COX-2 may restrict metastasis by limiting both prometastatic behaviors in individual tumor cells and mobilization of macrophages to the tumor vasculature.

A pilot study evaluating an abbreviated version of the cognitive remediation programme for youth with neurocognitive deficits

PRIMARY OBJECTIVE

To determine the effectiveness of an abbreviated version of an established cognitive remediation programme for children with neurological disorders and attention problems in an outpatient setting.

METHODS AND PROCEDURES

Eighteen 6-15-year-old children diagnosed with neurological and attention difficulties completed a six-module training programme aimed at improving attention. This programme was a shorter version of the Cognitive Remediation Programme (CRP), which has been successfully implemented with children with neurocognitive deficits. Parents completed measures of their children's attention and children completed neuropsychological measures of attention.

MAIN OUTCOMES AND RESULTS

The programme was associated with improvement in several aspects of parent-reported attention and children's performance on tasks measuring attention.

CONCLUSIONS

The shortened version of the CRP shows promise as a brief treatment for attention problems in outpatient neurological populations. Future research should assess programme effectiveness using a control group, longer-term follow-up and teacher reports.

Thiothymidine combined with UVA as a potential novel therapy for bladder cancer

BACKGROUND

Thiothymidine (S(4)TdR) can be incorporated into DNA and sensitise cells to DNA damage and cell death following exposure to UVA light. Studies were performed to determine if the combination of S(4)TdR and UVA could be an effective treatment for bladder cancer.

METHODS

Uptake and incorporation of S(4)TdR was determined in rat and human bladder tumour cell lines. Measures of DNA crosslinking and apoptosis were also performed. In vivo activity of the combination of S(4)TdR and UVA was investigated in an orthotopic model of bladder cancer in rats.

RESULTS

Thiothymidine (200 μM) replaced up to 0.63% of thymidine in rat and tumour bladder cancer cells. The combination of S(4)TdR (10-200 μM) and UVA (1-5 kJ m(-2)) caused apoptosis and cell death at doses that were not toxic alone. Addition of raltitrexed (Astra Zeneca, Alderley Edge, Cheshire, UK) increased the incorporation of S(4)TdR into DNA (up to 20-fold at IC(5)) and further sensitised cells to UVA. Cytotoxic effect was associated with crosslinking of DNA, at least partially to protein. Intravenous administration of S(4)TdR, in combination with UVA delivered directly to the bladder, resulted in an antitumour effect in three of five animals treated.

CONCLUSION

These data indicate that the combination of S(4)TdR and UVA has potential as a treatment for bladder cancer, and give some insight into the mechanism of action. Further work is necessary to optimise the delivery of the two components.

The role of folate receptor alpha (FRalpha) in the response of malignant pleural mesothelioma to pemetrexed-containing chemotherapy

Background:

The standard treatment of choice for malignant pleural mesothelioma is chemotherapy with pemetrexed and platinum, but the clinical outcome is poor. This study investigates the response to pemetrexed in a panel of eight mesothelioma cell lines and the clinical outcome for patients treated with pemetrexed in relation to folate receptor alpha (FRα).

Methods:

Cell lines were treated with pemetrexed to determine the concentration that reduced growth to 50% (GI₅₀). FRα expression was determined by western blotting and that of FRα, reduced folate carrier (RFC) and proton-coupled folate transporter (PCFT) by real-time quantitative RT–PCR. Immunohistochemistry for FRα was carried out on 62 paraffin-embedded samples of mesothelioma from patients who were subsequently treated with pemetrexed.

Results:

A wide range of GI₅₀ values was obtained for the cell lines, H2452 cells being the most sensitive (GI₅₀ 22 nM) and RS5 cells having a GI₅₀ value greater than 10 μM. No FRα protein was detected in any cell line, and there was no relationship between sensitivity and expression of folate transporters. FRα was detected in 39% of tumour samples, generally in a small percentage of cells. There was no correlation between the presence of FRα and the outcome of pemetrexed treatment, and no significant difference between histological subtypes.

Conclusion:

Response to treatment with pemetrexed does not depend on the presence of FRα.

Histological profile of tumours from MYCN transgenic mice

BACKGROUND

MYCN is the most commonly amplified gene in human neuroblastomas. This proto-oncogene has been overexpressed in a mouse model of the disease in order to explore the role of MYCN in this tumour.

AIMS

To report the histopathological features of neuroblastomas from MYCN transgenic mice.

METHODS

27 neuroblastomas from hemizygous transgenic mice and four tumours from homozygous mice were examined histologically; Ki67 and MYCN immunocytochemistry was performed in 24 tumours.

RESULTS

Tumours obtained from MYCN transgenic mice resembled human neuroblastomas, displaying many of the features associated with stroma-poor neuroblastoma, including heterogeneity of differentiation (but no overt ganglionic differentiation was seen), low levels of Schwannian stroma and a high mitosis karyorrhexis index. The tumours had a median Ki67 labelling index of 70%; all tumours expressed MYCN with a median labelling index of 68%. The most striking difference between the murine and human neuroblastomas was the presence of tingible body macrophages in the transgenic mouse tumours reflecting high levels of apoptosis. This has not previously been described in human or other murine neuroblastoma models.

CONCLUSIONS

These studies highlight the histological similarities between tumours from MYCN transgenic mice and human neuroblastomas, and reaffirm their role as a valuable model to study the biology of aggressive human neuroblastoma.

Fine-needle aspiration biopsy of monophasic variant of spindle epithelial tumor with thymus-like differentiation of the thyroid: report of one case and review of the literature

Spindle epithelial tumor with thymus-like differentiation (SETTLE) is a rare biphasic tumor of the thyroid with approximately 20 well-documented cases reported in the English literature. Although a monophasic variant of SETTLE is conceivable, the majority of the reported cases were truly biphasic tumors. A minimal amount of epithelial component was present in the reported cases of so-called spindle-cell predominant SETTLE. Here, we report an apparently monophasic case of SETTLE in a 16-yr-old girl, in which no epithelial cells were identified in either fine-needle aspiration biopsy (FNAB) or the subsequent hemithyroidectomy specimen. The FNAB smears were moderately cellular and composed of single and loosely grouped spindle cells with homogenous metachromatic material, which could be mistaken as amyloid, erroneously suggesting medullary thyroid carcinoma. The compact nodules of uniform spindle cells in histology sections raised the possibility of monophasic synovial sarcoma. The spindle cells stained positive for both cytokeratin and vimentin, but were negative for thyroglobulin and calcitonin as well as neuroendocrine markers, confirming the diagnosis of SETTLE.

Effects of potent VEGF blockade on experimental Wilms tumor and its persisting vasculature

We characterized the effect of potent vascular endothelial growth factor (VEGF) blockade on early-stage Wilms tumor xenograft growth, vasculature and metastasis. VEGF is a key mediator of both physiologic and tumor angiogenesis. We recently described that potent VEGF blockade induces regression of established Wilms tumor xenografts and vessels, also reducing the size but not the incidence of pre-existing metastases. In these studies, we examined the effects of potent VEGF blockade on earlier stages of experimental Wilms tumors, focusing on tumor growth, vasculature and metastasis. Athymic mice received intrarenal human Wilms tumor cell implants. Biweekly treatment with vehicle or the VEGF-Trap, a high-affinity soluble decoy receptor incorporating regions of VEGFR1 and VEGFR2, was begun 1 week later (100 or 500 micrograms/dose, n=20 in each group). Mice were euthanized at week 6 to examine tumor weight, incidence of lung metastases, vascularity and expression of angiogenic factors. A cohort of mice was examined 2 weeks after cessation of treatment. Compared to controls, VEGF-Trap treated tumors were significantly smaller (100 micrograms/dose: 92.7% smaller, p=0.0017; 500 micro g/dose: 99.0% smaller, p=0.0009). The incidence of lung metastasis also decreased significantly (p<0.0055). VEGF-Trap nearly eradicated tumor vasculature. Rare persisting vessels were characterized by large caliber, quiescence (lacking proliferation/apoptosis) and arterialization (both phenotypic and molecular). Potent VEGF blockade caused near-arrest of experimental Wilms tumor growth, resulted in nearly avascular tumors, and also decreased the incidence and size of metastases. Persistent vessels in tumors treated with VEGF-Trap displayed specific morphologic and molecular features, suggestive of arterialization. Future strategies that target these persisting vessels may enhance the efficacy of VEGF blockade therapy.

Vascular Remodeling Marks Tumors That Recur During Chronic Suppression of Angiogenesis

The potential for avoiding acquired resistance to therapy has been proposed as one compelling theoretical advantage of antiangiogenic therapy based on the normal genetic status of the target vasculature. However, previous work has demonstrated that tumors may resume growth after initial inhibition if antiangiogenic blockade is continued for an extended period. The mechanisms of this recurrent growth are unclear. In these studies, we characterized molecular changes in vasculature during apparent resumption of xenograft growth after initial inhibition by vascular endothelial growth factor blockade, “metronome” topotecan chemotherapy, and combined agents in a xenograft murine model of human Wilms' tumor. Tumors that grew during antiangiogenic blockade developed as viable clusters surrounding strikingly remodeled vessels. These vessels displayed significant increases in diameter and active proliferation of vascular mural cells and expressed platelet-derived growth factor-B, a factor that functions to enhance vascular integrity via stromal cell recruitment. In addition, remodeled vessels were marked by expression of ephrinB2, required for proper assembly of stromal cells into vasculature. Thus, enhanced vascular stability appears to characterize tumor vessel response to chronic antiangiogenesis, features that potentially support increased perfusion and recurrent tumor growth.

Vascular remodeling marks tumors that recur during chronic suppression of angiogenesis

The potential for avoiding acquired resistance to therapy has been proposed as one compelling theoretical advantage of antiangiogenic therapy based on the normal genetic status of the target vasculature. However, previous work has demonstrated that tumors may resume growth after initial inhibition if antiangiogenic blockade is continued for an extended period. The mechanisms of this recurrent growth are unclear. In these studies, we characterized molecular changes in vasculature during apparent resumption of xenograft growth after initial inhibition by vascular endothelial growth factor blockade, "metronome" topotecan chemotherapy, and combined agents in a xenograft murine model of human Wilms' tumor. Tumors that grew during antiangiogenic blockade developed as viable clusters surrounding strikingly remodeled vessels. These vessels displayed significant increases in diameter and active proliferation of vascular mural cells and expressed platelet-derived growth factor-B, a factor that functions to enhance vascular integrity via stromal cell recruitment. In addition, remodeled vessels were marked by expression of ephrinB2, required for proper assembly of stromal cells into vasculature. Thus, enhanced vascular stability appears to characterize tumor vessel response to chronic antiangiogenesis, features that potentially support increased perfusion and recurrent tumor growth.

Blockade of her2/neu decreases VEGF expression but does not alter HIF-1 distribution in experimental Wilms tumor

Her2/neu regulates angiogenesis in human breast cancer, in part by stabilizing hypoxia-inducible factor 1alpha (HIF-1alpha), causing accumulation of the HIF-1 heterodimer and thus increasing expression of the proangiogenic cytokine VEGF. Her2/neu has recently been shown to be overexpressed in a subset of Wilms tumors. Using her2/neu (+) and her2/neu (-) Wilms tumor cell lines, we tested the effect of blocking anti-her2/neu antibody in vitro and in vivo. Blocking antibody did not alter VEGF expression in vitro, but decreased expression of VEGF in her2/neu (+) Wilms tumor xenografts. Tumor suppression was less marked than in parallel experiments using agents directly blocking VEGF. HIF-1alpha immunostaining was not altered in her2/neu (+) xenografts exposed to blocking antibody. These results suggest that her2/neu contributes to Wilms tumor angiogenesis in vivo by regulating VEGF, but other processes may act to rescue HIF-1alpha and thus to support tumor growth in this system.

Regression of established tumors and metastases by potent vascular endothelial growth factor blockade

Vascular endothelial growth factor (VEGF) is a critical promoter of blood vessel growth during embryonic development and tumorigenesis. To date, studies of VEGF antagonists have primarily focused on halting progression in models of minimal residual cancer. Consistent with this focus, recent clinical trials suggest that blockade of VEGF may impede cancer progression, presumably by preventing neoangiogenesis. However, VEGF is also a key mediator of endothelial-vascular mural cell interactions, a role that may contribute to the integrity of mature vessels in advanced tumors. Here, we report that high-affinity blockade of VEGF, using the recently described VEGF-Trap, abolishes mature, preexisting vasculature in established xenografts. Eradication of vasculature is followed by marked tumor regression, including regression of lung micrometastases. Thus, the contribution of relatively low levels of VEGF to vessel integrity may be critical to maintenance of even very small tumor masses. Potent blockade of VEGF may provide a new therapeutic option for patients with bulky, metastatic cancers.

p53 accumulation in favorable-histology Wilms tumor is associated with angiogenesis and clinically aggressive disease

BACKGROUND/PURPOSE

Unfavorable histology (UH) in Wilms tumor has been linked to malfunction of the p53 tumor suppressor gene, which regulates (1) the endogenous angiogenesis suppressor thrombospondin-1 (TSP-1) and (2) vascular endothelial growth factor (VEGF). The authors hypothesized that clinically aggressive favorable histology Wilms tumor (FH), like UH, but distinct from standard-risk FH disease, would display altered p53/TSP-1 function and upregulated angiogenesis.

METHODS

Three Wilms tumor specimens manifesting different histology and clinical behavior were obtained: clinically aggressive UH, clinically aggressive FH, and standard-risk FH disease. Xenografts were induced intrarenally in athymic mice. P53, TSP-1, and VEGF status and neovascularity were assessed in tumor tissues. Lungs were evaluated for metastasis.

RESULTS

Clinically aggressive FH Wilms tumor displayed progressive alteration in p53/TSP-1 status and upregulation of VEGF. Such alteration was observed in the UH tumor, but was absent from the standard-risk FH tumor. Xenografts from clinically aggressive tumors displayed brisk neoangiogenesis and yielded lung metastases.

CONCLUSIONS

This is the first report of altered p53/TSP-1 function in association with clinically aggressive behavior in FH Wilms tumor. These characteristics were not observed in parallel studies of a nonaggressive FH tumor. Loss of wild-type p53 function may contribute to disease progression in FH Wilms tumor, in part by upregulation of VEGF.

Resistance of a VEGF-producing tumor to anti-VEGF antibody: unimpeded growth of human rhabdoid tumor xenografts

BACKGROUND/PURPOSE

Rhabdoid tumor of the kidney (RTK) is a lethal malignancy of childhood for which there currently are no effective therapies. Because vascular endothelial growth factor (VEGF) is nearly ubiquitous in human tumors, the authors hypothesized that a xenograft model of RTK would (1) express VEGF and (2) respond to anti-VEGF intervention.

METHODS

A total of 2 x 10(6) cultured RTK cells were implanted intrarenally (G-401) in athymic mice. Control/treated animals received either vehicle (phosphate-buffered saline, PBS) or anti-VEGF antibody (anti-VEGF) for 5 weeks (n = 20, 17, respectively). Vasculature was mapped by angiography and immunostaining. Apoptosis was assessed by TdT-mediated dUTP nick end labeling (TUNEL) assay, VEGF expression examined by reverse transcription polymerase chain reaction, and tumor weights compared by Kruskal-Wallis analysis.

RESULTS

Mean tumor weights were not altered significantly by anti-VEGF (0.78-g, controls v 0.56-g treated tumors; P value, not significant). Grossly, xenografts grew in a novel manner, encasing rather than invading the kidney, and did not metastasize. PECAM-1 immunostaining and fluorescein angiography showed similar vascularity in control and treated xenografts. Both apoptosis and VEGF expression were unchanged in treated specimens.

CONCLUSIONS

Unexpectedly, growth of RTK xenografts was not inhibited by specific anti-VEGF antibody, although these tumors express significant amounts of VEGF. In addition, RTK vasculature, apoptosis, and VEGF expression were not substantially altered by anti-VEGF antibody. These results suggest that tumor-derived VEGF is of highly variable importance in different malignancies.

Novel use of an established agent: Topotecan is anti-angiogenic in experimental Wilms tumor

BACKGROUND/PURPOSE

Antiangiogenic agents offer a new approach to the treatment of aggressive neoplasms, yet very few agents are available for current use. The authors have shown previously the efficacy of antiangiogenic therapy in experimental Wilms tumor, using an investigative antibody. They hypothesized that topotecan, administered in a regimen targeting endothelial cells, would suppress tumor growth and angiogenesis in experimental Wilms tumor.

METHODS

Experimental tumors were induced in the left kidneys of athymic mice by injection of cultured Wilms tumor cells. Topotecan (0.36, 0.6, 1.0, 2.0, and 3.0 mg/kg) or vehicle was injected intraperitoneally in 2 cycles over a 6-week period. Fluorescein angiograms and platelet endothelial cell adhesion molecule-1 staining of primary tumors were performed to ascertain vascular architecture. Endothelial apoptosis was assessed by TdT-mediated dUTP nick end labeling assay.

RESULTS

Tumor weights were reduced significantly in treated versus control animals, even in the lowest-dose group. Endothelial cell staining and angiography results showed relatively sparse vascularity in treated xenografts. Endothelial apoptosis was observed in treated but not control tumors.

CONCLUSIONS

Topotecan, delivered in an "antiangiogenic" regimen, even at very low doses, significantly inhibited growth of experimental Wilms tumors. No adverse effects were noted at low doses. Thus, the established chemotherapy agent topotecan may be useful in a novel role: as antiangiogenic therapy. J Pediatr Surg 36:1781-1784.

Combination antiangiogenic therapy: increased efficacy in a murine model of Wilms tumor

BACKGROUND/PURPOSE

Antibody to vascular endothelial growth factor (anti-VEGF) suppresses tumor growth and metastasis in experimental Wilms tumor. However, tumor growth accelerates if antibody is withdrawn. As recently shown, low-dose, frequently administered topotecan, a topoisomerase-1 inhibitor, has anti-angiogenic activity. The authors hypothesized that combined topotecan/anti-VEGF therapy would suppress tumor growth and metastasis more durably than either agent alone.

METHODS

Xenografts were induced by intrarenal injection of human Wilms tumor cells in athymic mice (n = 59). Mice were divided into control (n = 10), anti-VEGF (n = 16), topotecan (n = 17), and topotecan plus anti-VEGF (n = 16) groups. All control and half the treated mice were killed at week 6. Remaining ("rebound") mice were maintained without treatment until week 8. Tumor vasculature was mapped by fluorescein angiography/PECAM immunostaining. Endothelial apoptosis was assessed by TUNEL assay.

RESULTS

6 weeks: Tumor weights were reduced significantly in treated mice (P <.003 v control). Seven of ten control and 1 of 25 treated mice displayed lung metastases (P <.003). Rebound tumors were largest in topotecan-only, intermediate in antibody-treated, and smallest in combination-treated mice. Immunostaining and angiography results showed sparse vascularity in treated xenografts. Endothelial apoptosis was observed only in treated tumors.

CONCLUSION

Combination low-dose topotecan and anti-VEGF antibody therapy is antiangiogenic and suppresses tumor growth and metastasis in experimental Wilms tumor more durably than either agent alone.

Highly specific antiangiogenic therapy is effective in suppressing growth of experimental Wilms tumors

BACKGROUND/PURPOSE

Pathologic angiogenesis in tumors is a potential target for novel therapies. Vascular endothelial growth factor (VEGF) is an angiogenic promoter present in a wide variety of human tumors. VEGF is expressed as 4 isoforms; one of these, VEGF165, predominates in human tumors. The authors hypothesized that antagonism of VEGF165 by a specific aptamer would block tumor growth in an experimental model of Wilms tumor.

METHODS

VEGF isoform expression in clinical (n = 2) and experimental tumors were evaluated by reverse transcription polymerase chain reaction (RT-PCR). Tumors were induced in NCR nude mice (n = 32) by intrarenal injection of 10(6) cultured Wilms tumor cells. At 1 week, aptamer (n = 16) or vehicle (n = 16) treatment was started and continued daily for 5 weeks.

RESULTS

At 6 weeks tumors weighed 84% less in treated versus control animals (0.69 v 4.41 g; P <.028), without observed adverse effects and similar to suppression previously reported using nonisoform-specific anti-VEGF antibody (94% to 96%).

CONCLUSIONS

Anti-VEGF165 aptamer effectively suppressed primary tumor growth in experimental animals with no observed adverse effects. Development of highly specific antiangiogenic therapies may be of particular benefit to pediatric patients.

All angiogenesis is not the same: Distinct patterns of response to antiangiogenic therapy in experimental neuroblastoma and Wilms tumor

BACKGROUND/PURPOSE

Neuroblastoma and Wilms tumor exhibit different patterns of metastasis, invasion, and therapeutic response. Vascular endothelial growth factor (VEGF) is an angiogenic factor expressed in both tumors. The authors hypothesized that because the clinical behavior of these tumors differs, the response to anti-VEGF therapy would be distinct, and tumor vascular architectures would reflect this distinction.

METHODS

Xenografts were induced by intrarenal injection of cultured cells in athymic mice. After 1 week, anti-VEGF antibody or vehicle were administered for 5 weeks before sacrifice. Additional animals were maintained for 3 weeks after termination of antibody injections to assess rebound growth of tumors. Fluorescein angiography was performed in selected animals.

RESULTS

Neuroblastoma control and treated tumor weights were not significantly different (1.48 g v 0.77 g, P =.34). By comparison, as previously reported, antibody-treated Wilms tumors were growth inhibited. Angiograms of treated (but not control) neuroblastomas displayed novel rounded structures at vessel branches, which the authors term terminal vascular bodies (TVBs). Wilms tumor vessels displayed no such alteration.

CONCLUSIONS

Neuroblastoma xenografts are less effectively suppressed by anti-VEGF antibody than Wilms tumors. Neuroblastoma vascular architecture displays a novel alteration during antibody administration, which attenuates when antibody is withdrawn. These studies suggest that angiogenesis is differently regulated in experimental neuroblastoma and Wilms tumor.

Transurethral hot-water balloon thermoablation for benign prostatic hyperplasia: patient tolerance and pathologic findings

OBJECTIVES

To determine the patient tolerance and thermal ablation pattern in human prostatic tissue after treatment with a hot water, catheter-based system.

METHODS

Twenty-seven men scheduled for surgery for symptomatic benign prostatic hyperplasia or adenocarcinoma of the prostate underwent water-induced thermotherapy. The patients were randomly assigned to one of four treatment groups. Lidocaine gel was the sole means of pain control. The patients and an observer recorded patient discomfort during therapy. A Foley catheter was left in place until surgery (n = 13) or successful voiding (n = 14). Prostates were subsequently enucleated or removed, whole mounted, and examined.

RESULTS

Patients reported mild treatment discomfort, the level of which did not correlate with the extent of necrosis, balloon diameter, or water temperature (all P >0. 05). Distal penile burning was the most commonly reported discomfort. All 14 patients successfully voided within 12 days of treatment. Prostates were enucleated (n = 24) or removed (n = 3) at a mean of 27 days (range 4 to 120) after thermotherapy, except for a single adenectomy 17 months after therapy. Pathologic findings included periurethral hemorrhagic necrosis, with focal or extensive urothelial denudation and mild inflammation. The mean maximal depth of necrosis from the urethral lumen was 7, 9, 10.33, and 11 mm in groups 1, 2, 3, and 4, respectively. The extent of necrosis was similar in all groups (P = 0.11), regardless of the water temperature; conversely, the balloon diameter correlated with the depth of necrosis (P = 0.024).

CONCLUSIONS

This system of tissue ablation appears to be well tolerated, and it produced consistent pathologic results.

Hyperbaric oxygen therapy for hepatic artery thrombosis after liver transplantation in children

Early hepatic artery thrombosis (HAT) after pediatric orthotopic liver transplantation (OLT) can cause significant morbidity and mortality, leading to liver failure or septic complications requiring urgent retransplantation. Experimental evidence that hyperbaric oxygen (HBO) may ameliorate hepatic ischemic-reperfusion injury led to this study of HBO in pediatric liver transplant recipients who developed HAT. Children undergoing OLT under primary tacrolimus immunosuppression and University of Wisconsin organ preservation between August 1, 1989, and December 31, 1998, who developed HAT were the basis for this study. Patients who developed HAT between March 1, 1994, and December 31, 1998, were treated with HBO therapy until signs of ischemia resolved (absence of fever, normalizing liver injury test results) or for 2 weeks. The pediatric OLTs performed from August 1, 1989, to February 28, 1994, who developed HAT served as a control group. Primary outcome measures were survival, retransplantation rate, time to retransplantation, incidence of hepatic gangrene, and days to collateral formation. Three hundred seventy-five consecutive pediatric patients underwent 416 OLTs between August 1, 1989, and December 31, 1998. Thirty-one patients (7.5%) developed HAT at a mean time of 8.2 days (range, 1 to 52 days) post-OLT. In 17 patients, HBO treatment was begun within 24 hours of HAT or immediately after the revascularization attempt and performed twice daily for 90 minutes at 2.4 atmospheres pressure. Fourteen patients were treated without HBO. None of the HBO-treated patients developed hepatic gangrene. Eight HBO patients (47%) were bridged to retransplantation at a mean time of 157 days (range, 3 to 952 days) after initial OLT and all survived. Mean time to retransplant in the control group was 12.7 days (range, 1 to 64 days). HBO was well tolerated without significant complications. Although there was no significant difference in survival or retransplantation rates, HBO significantly delayed retransplantation, potentially by hastening the development of hepatic artery collaterals.

Androgen induction of DNA synthesis in the rat penis

OBJECTIVES

The androgen sensitivity of the mammalian penis has long been appreciated. However, the precise biochemical and structural sequelae of alterations in testosterone, and the mechanisms thereof, remain to be elucidated. Recently, the androgen dependence of rat penile erectile tissue was further clarified at our institution, where the induction of apoptosis was demonstrated in response to castration. In continuity, we report the results of a follow-up study of the regenerative capacity of the regressed, castrated rat penile erectile tissue when testosterone is replenished.

METHODS

Three groups of rats were used: normal control rats, castrated without testosterone replenishment, and castrated with subsequent testosterone replenishment. In the third group, castrated rats were given testosterone and killed at 24-hour intervals over 4 days. Specimens of the penis, small bowel, and prostate were obtained from all animal groups. Immunohistochemical identification of intraperitoneally administered 5-bromo-2'-deoxyuridine, a thymidine analogue, was performed to detect new DNA synthesis. The incorporation of this molecule into high molecular weight nuclear DNA served as a measure of DNA synthesis and, hence, cellular proliferation.

RESULTS

Testosterone-replenished castrated rat penile stromal cells, both cavernosal and spongiosal, showed more enhanced proliferative activity than those of both castrated unreplenished and uncastrated control rats. Trichrome staining permitted the differentiation of responsive cell subsets. Various cell types were found to respond to replenished testosterone, including myocytes, fibrocytes, endothelial cells, and Schwann cells. Pronounced DNA synthesis occurred as early as 48 hours after the replenishment of testosterone. For purposes of technique validation, sections of small bowel were examined, in which glandular crypt cells would be expected to show rapid turnover. The nuclei of these bowel sections stained in all animal groups throughout the experiment, thus validating the staining technique. The technique of castration and testosterone replenishment was validated by confirming the known response of rat ventral prostate to androgen withdrawal and replenishment.

CONCLUSIONS

Our findings provide evidence that testosterone induces cellular proliferation and new DNA synthesis in the penile erectile tissue of castrated rats. This response to testosterone is not limited to one cell type, but rather is multicellular.

The outcome of unrelated donor bone marrow transplantation in patients with hematologic malignancies using tacrolimus (FK506) and low dose methotrexate for graft-versus-host disease prophylaxis

Initial studies of FK506 combined with methotrexate (MTX) in patients receiving unrelated donor BMT have demonstrated a possible-decrease in the incidence of severe GVHD but high rates of severe stomatitis and nephrotoxicity. With this background, we undertook a pilot study evaluating FK506 in combination with a lower than usual dose of MTX in an attempt to improve the tolerability of this immunoprophylaxis regimen. Between July 1993 and October 1994, 26 consecutive adults receiving unrelated donor BMT at Emory University Hospital were enrolled on this study. All patients received FK506 intravenously at an initial dose of 0.03 mg/kg/day beginning day -1 and continuing until oral FK506 was tolerated. Patients also received MTX intravenously at 5 mg/m2 on days 1, 3, 6, and 11. The preparative regimen administered to all but one patient included cyclophosphamide at 200 mg/kg over 4 days followed by total body irradiation (TBI) at 1400 cGy in twice daily fractions over 4 days. The median age of patients was 31 years (range: 19 to 52). Sixteen donor/recipient pairs were matched for HLA-A, -B, and -DR by serology and molecular typing. Ten paris were minor mismatches at either class I or class II. Twenty-two of 26 patients (85%) completed four doses of MTX on schedule. Nephrotoxicity was the most common adverse event associated with the administration of FK506: 88% of patients experienced a doubling of their serum creatinine. One patient died of central nervous system hemorrhage prior to engraftment. Twenty-four of the remaining 25 patients (96%) engrafted. Fourteen of 24 patients (50%) evaluable developed grades 2-4 acute GVHD. The rate of severe (grades 3-4) acute GVHD was 25%. Chronic GVHD developed in 11 of 20 (55%) evaluable patients. At a median follow-up of 461 days, 14 patients (54%) are alive. All are relapse-free with a median Karnofsky performance status of 90% (range: 70-100%). The cumulative probability of 2-year disease-free survival is 50% (95% confidence interval [CI]: 0.33 to 0.77); for low risk patients 67% (95% CI: 0.47 to 0.95) and for high risk patients 23% (95% CI: 0.049 to 1.00). These preliminary data indicate that FK506-based immunosuppression following unrelated donor BMT is effective in preventing severe acute GVHD and warrants comparison to CSA-based regimens.

Effects of methylphenidate on attention and nonverbal learning in children with attention-deficit hyperactivity disorder

OBJECTIVE

To examine effects of methylphenidate (MPH) doses on attention and learning tasks requiring varying levels of processing in 23 children with attention-deficit hyperactivity disorder.

METHOD

Performance on a continuous performance task (CPT) and two difficulty levels of a nonverbal learning task was evaluated on two doses of MPH (0.3 mg/kg and 0.8 mg/kg) and placebo.

RESULTS

CPT commission errors were significantly reduced with low-dose MPH compared with placebo while omission errors were not medication-sensitive. Performance on nonverbal learning tasks was significantly improved with MPH. On the easy level of the nonverbal learning task performance improved equally well with either dose. On the hard level, performance was significantly better at the high dose compared with placebo; no between-dose differences emerged across learning trials. However, the high dose was superior to low and placebo doses in memory recall trials.

CONCLUSIONS

Impulsivity may be reduced on an attentional task with a low dose of MPH, and a high dose of MPH may optimize retention and recall of complex nonverbal information.

Allogeneic bone marrow transplantation with matched unrelated donors for patients with hematologic malignancies using a preparative regimen of high-dose cyclophosphamide and fractionated total body irradiation

Allogeneic bone marrow transplantation (BMT) from an HLA-identical sibling donor is effective therapy for patients with bone marrow failure states and those with hematologic malignancies. However, only a minority of them will have an HLA-identical sibling donor; unrelated donors, matched or partially mismatched, have been used successfully for patients lacking a related donor. Even though results with allogeneic transplants using unrelated donors are encouraging, the incidence of complications including graft-versus-host disease (GVHD) and graft rejection or late graft failure is increased compared to identical sibling transplants. The combination of cyclophosphamide and total body irradiation (TBI) has been used as an effective preparative regimen for allogeneic transplants, however, the total dosage and dosing schedule of both the cyclophosphamide and TBI has varied significantly among studies. To decrease the rate of graft rejection and late graft failure with volunteer donors, we evaluated a preparative regimen of high-dose cyclophosphamide (200 mg/kg over 4 consecutive days, days -8, -7, -6, -5) followed by fractionated TBI (1400 cGy administered in eight fractions over 4 days, days -4, -3, -2, -1). GVHD prophylaxis included FK506 and methotrexate. From July 1993 to January 1996, 43 adult patients, median age 38 years (range 18-58 years), were treated with this preparative regimen. Seventeen patients had low-risk disease and 26 had high-risk disease. Thirty-one donor/recipient pairs were matched for HLA-A, -B, and -DR by serology and molecular typing. Seven additional pairs were minor mismatched at the HLA-A or HLA-B loci. Four other donor/recipient pairs were HLA-A,-B, and -DR identical by serology but allele mismatched at either DRB1 or DQB. Forty patients were evaluable for myeloid engraftment. Engraftment occurred in all 40 patients at a median of 19 days. There were no cases of graft rejection or late graft failure. Nephrotoxicity was the primary adverse event with 26 patients (60%) experiencing a doubling of their creatinine. Hepatic veno-occlusive disease occurred in seven patients, six of whom had high-risk disease. All patients who had relapsed or refractory disease prior to BMT achieved a complete remission following BMT. Six patients transplanted for high-risk disease relapsed a median of 377 days post-BMT. None of the patients with low-risk disease have relapsed following transplant; the Kaplan-Meier survival for those patients with low-risk disease is 62% and 37% for those patients transplanted with high-risk disease (P = 0.0129). The median Karnofsky performance status is 100% (range 70-100%). Therefore, a preparative regimen of high-dose cyclophosphamide and fractionated TBI is an acceptable regimen for patients receiving an allograft from unrelated donors.

Telemedicine: videoconferencing in medicine

Ten years ago the professional concern of the medical illustrator was limited to the fields of film-based image acquisition and traditional artists media. The development of affordable digital cameras and computer based illustration software is shifting the balance to computers so that currently both artists and photographers use similar tools. Telemedicine is defined by the European Foundation for the Improvement of Living and Working Conditions as: 'The use of telecommunications and informatics for medical and health purposes'. Telemedicine may incorporate medical video, still image and document transfer which may have originated in medical illustration departments. The paper attempts to explain some of the basic concepts associated with telemedicine and it's medium: videoconferencing.

The role of the reverse-transcriptase polymerase chain reaction assay for prostate-specific antigen in the selection of patients for radical prostatectomy

Prostate cells present in the peripheral circulation can be detected using an enhanced reverse-transcriptase polymerase chain reaction (RT-PCR) for prostate-specific antigen (PSA) assay. In one study, preoperative enhanced RT-PCR for PSA status was a significant predictor of surgical pathology and postoperative biomechanical recurrence. The use of RT-PCR may enhance the urologist's ability to stage potential candidates for radical prostatectomy, as the assay is a more sensitive and specific predictor of microscopic extracapsular extension than conventional staging modalities. This highly adaptable assay also may have roles in screening for recurrence and in staging other solid tumors.

Giant multilocular cystadenoma of the prostate

Giant multilocular prostatic cystadenoma is a rare clinicopathologic entity characterized by benign histology and the ability to enlarge massively. The lesion may arise from the prostate gland either in continuity with the prostatic urethra or separate from it, or it may arise as a lesion distinct from the prostate gland. Obstructive voiding symptoms occur in all reported cases. The use of preoperative radiographic evaluation, such as magnetic resonance imaging, effectively defines the lesion's benign nature and aids in planning surgical extirpation.

Preoperative reverse transcriptase polymerase chain reaction for prostate specific antigen predicts treatment failure following radical prostatectomy

PURPOSE

We previously demonstrated than an enhanced reverse transcriptase-polymerase chain reaction assay for prostate specific antigen (PSA) can predict final pathological stage in radical prostatectomy patients. The potential role of the assay in predicting serum PSA recurrence after radical prostatectomy was explored.

MATERIALS AND METHODS

We evaluated 100 radical prostatectomy candidates by reverse transcriptase polymerase chain reaction preoperatively, and status was compared to serum PSA, Gleason score and final pathological results. Potential surgical failure was defined as tumor at the surgical margin or extending into the seminal vesicle. Patients were monitored postoperatively by serum PSA every 4 months. Kaplan-Meier analysis was used to evaluate the correlation between reverse transcriptase polymerase chain reaction and disease recurrence, defined as a PSA of 0.2 ng/ml. or greater.

RESULTS

Enhanced reverse transcriptase polymerase chain reaction for PSA had a stronger correlation with potential surgical failure than preoperative serum PSA or Gleason score (relative risks 15.2, 5.9 and 3.2, respectively). The correlation between these modalities and PSA recurrence was evaluated during a mean followup of 13.6 months (range 5 to 26). Of 36 patients with positive reverse transcriptase polymerase chain reactions 9 had failure by PSA compared to 3 of 64 (4.7%) with negative polymerase chain reactions (p<0.0286). The relative risk for failure by reverse transcriptase polymerase chain reaction was 3.6. Gleason score and serum PSA had higher correlations with postoperative PSA elevations (relative risk 13.2 and 7.6, respectively). A Cox regression analysis model demonstrated that reverse transcriptase polymerase chain reaction for PSA can be used in conjunction with Gleason score and provides statistically significant risk information.

CONCLUSIONS

Enhanced reverse transcriptase polymerase chain reaction for PSA is a statistically significant predictor of potential failure by pathological analysis and of disease recurrence by PSA. Longer followup data are required to define further the role of the assay in the management of patients with prostate cancer.

The use of RT-PCR for prostate-specific antigen assay to predict potential surgical failures before radical prostatectomy: molecular staging of prostate cancer

OBJECTIVE

To assess the potential role of a recently developed reverse transcriptase-polymerase chain reaction (RT-PCR) assay for prostate-specific antigen (PSA), that detects circulating prostate cells in patients with prostate cancer, in the management of clinically localized cancer.

PATIENTS AND METHODS

A total of 138 men (mean age 62.5 years, range 49-70) scheduled for radical retropubic prostatectomy had an RT-PCR assay before surgery. The results were compared with the final pathological stage of disease, the results from local imaging techniques, serum PSA levels, digital rectal examination (DRE) and Gleason score.

RESULTS

Enhanced RT-PCR for PSA was the best predictor of potential surgical failures; 70% of patients with positive surgical margins or invasion into the seminal vesicle were identified pre-operatively by a positive RT-PCR assay (odds ratio = 12.0, positive predictive value = 64%, negative predictive value = 87%). RT-PCR was able to identify pre-operatively patients with adverse pathology, despite low serum PSA values (< 4.0 ng/mL). In patients with high PSA level (> 10 ng/mL), RT-PCR discriminated between potentially curable candidates and those with established extraprostatic disease.

CONCLUSIONS

RT-PCR for PSA adds unique prognostic information when considering patients for radical surgery. The final role for the RT-PCR assay is as yet undefined; however, the ability to detect potential surgical failures pre-operatively using a molecular approach should have a significant impact on the management of patients with prostate cancer.

Peripherin: a novel marker for the immunohistochemical study of malformations of the enteric nervous system

Pheripherin is a 57-kD type III intermediate filament that is a specific marker for peripheral neruons, including enteric ganglion cells (GCs). Hence antibodies to peripherin may be used to demonstrate abnormalities of the enteric nervous system (ENS). Serial longitudinal histologic sections of formalin-fixed paraffin-embedded colons from 15 patients were immunostained for peripherin, neuron-specific enolase (NSE), neurofilaments, S-100, and synaptophysin. Ten patients had variable degrees of colonic aganglionosis (Hirschsprung's disease), three were premature in infants, and two were controls. Peripherin labeling yielded the highest number of recognizable GCs. Overall, 56%, 78%, and 80% of the peripherin-positive GCs in the myenteric plexus were identified by staining for neurofilaments, NSE, and S-100, respectively. Intramucosal GCs were detected in 4 of 10 cases of Hirschspring's disease (HD), none of which had been evident by routine histology. The other neuronal markers were less specific for intramucosal GCs than peripherin, because they also added enterochromaffin cells. Peripherin immunohistochemistry also allowed exact quantification of GC density expressed as GCs/mm colon, which is important for the diagnosis of HD-related disorders. In three cases of HD the GC density of the transition zone was markedly elevated compared with more proximal ganglionic bowel segments, consistent with neuronal intestinal dysplasia type B, and two cases of HD showed low GC density within the transition zone. Hence peripherin immunolabeling may prove to be a valuable aid in the diagnosis and classification of congenital malformations of the ENS.

Thrombotic thrombocytopenic purpura associated with FK506 following bone marrow transplantation

Thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS) have been observed after bone marrow transplantation (BMT), typically occurring 1-6 months following BMT. We describe two patients who developed TTP very early after BMT while receiving intravenous FK506. They were treated with platelet support and plasma exchange (PE) using either fresh frozen plasma (FFP) or cryosupernatant fraction of plasma (CFP), resulting in remission of TTP activity.

The incidence of multifocal renal cell carcinoma in patients who are candidates for partial nephrectomy

PURPOSE

A prospective study was performed to determine the incidence of multifocal renal cell carcinoma in patients who are candidates for partial nephrectomy.

MATERIALS AND METHODS

Preoperative imaging studies and surgical specimens in 44 patients suitable for partial nephrectomy but undergoing radical nephrectomy were prospectively reviewed.

RESULTS

Of 44 renal cell cancers 11 (25%) demonstrated pathological multifocality, while 10 of 11 multifocal tumors (91%) occurred in the face of a primary tumor 5 cm. or smaller. Tumor multifocality was independent of the size of the primary renal tumor but occurred with a slightly higher frequency in tumors of stage T3A or greater even if the primary tumor was small.

CONCLUSIONS

Partial nephrectomy in patients with unilateral renal cancer should be approached with caution and should not be performed simply because it is technically feasible.