Retinal dysplasia mimicking intraocular tumor: MR imaging findings with histopathologic correlation

We report a 6-month-old boy who presented with unilateral leukocoria, retinal detachment, and a retrolental mass in a microphthalmic eye based on retinal dysplasia with concurrent optic nerve aplasia. Dysplastic retinal tissue, a rare congenital defect, may create a clinical and radiologic picture of an intraocular mass closely resembling tumor tissue. MR imaging findings with histopathologic correlation are presented to facilitate discrimination of the more common causes of leukocoria.

Has the degree of contrast enhancement with MR imaging in laryngeal carcinoma added value to anatomic parameters regarding prediction of response to radiation therapy?

BACKGROUND AND PURPOSE

Our aim was to retrospectively investigate the prognostic significance of the degree of contrast enhancement in tumors and its additional value in previously considered MR imaging parameters with regard to local control of laryngeal cancer treated with radiation therapy (RT) alone.

MATERIALS AND METHODS

Pretreatment MR images of 64 consecutive patients (54 men and 10 women, 43-80 years of age) with supraglottic and glottic cancer were retrospectively reviewed on clinical and previously considered MR imaging parameters such as tumor involvement of specific laryngeal anatomic subsites, including laryngeal cartilages, tumor volume, extralaryngeal tumor spread, and, in addition, the degree of contrast enhancement. Clinical and MR imaging parameters were associated with regard to local control at 2 years by using the Cox regression model. "Local control" was defined as absence of primary tumor recurrence.

RESULTS

When using a threshold of the mean average contrast enhancement of 77%, the 2-year local control rate in the groups of patients with a degree of enhancement below and above this threshold was 57% and 70%, respectively (P=.3). Enhancement of tumor tissue in pre-epiglottic space (PES) was low, most probably due to its adipose tissue and poor vascular content, whereas tumor tissue involving paraglottic space (PGS) did enhance. Results of multivariate analysis indicated that the degree of contrast enhancement yielded the prognostic information (P=.07) with 2 independent prognostic factors: primary tumor volume (P=.007) and subglottic extension (P=.002) with regard to local control. Using these previously mentioned 3 MR imaging parameters as potential risk factors, we defined 4 categories, resulting in the following local control rates respectively: 90% for the group without risk factors, 73% for the group with 1, 60% for the group with 2, and finally 0% for the group with 3 risk factors, which was significantly lower than the rates in previous risk groups (P < .001).

CONCLUSION

PES has a lower degree of contrast enhancement than the PGS and may correlate with the worse outcome. Including a low degree of contrast enhancement as a parameter to primary tumor volume and subglottic extension may increase the predictive value of MR imaging for local outcome and may be helpful to identify a subset of patients whose tumors all recurred locally within 2 years after primary RT.

Matrix metalloproteinase-19 is highly expressed in active multiple sclerosis lesions

Matrix metalloproteinases (MMPs) are proteases known for their capacity to degrade extracellular matrix (ECM) components. MMPs have been implicated in several central nervous system (CNS) diseases, including multiple sclerosis (MS). Microarray analysis has demonstrated significant increased mRNA levels of MMP-19 in chronic MS lesions, suggesting a role of MMP-19 in MS pathogenesis. Therefore, in this study, we investigated the expression pattern and cellular localization of MMP-19 protein in various well-characterized MS lesion stages. In normal control patient white matter, MMP-19 was constitutively expressed by microglia throughout the brain parenchyma, suggesting a physiological role for this MMP family member. Likewise, MMP-19 was expressed by microglia in (p)reactive MS lesions, albeit more intense. In highly active demyelinating MS lesions, parenchymal and perivascular myelin-laden macrophages were strongly immunoreactive for MMP-19, whereas reactive astrocytes were occasionally immunopositive. Astrocytes in chronic inactive lesions were weakly stained for MMP-19. In vitro, MMP-19 was expressed in cultures of primary human microglia, not in astrocyte cultures. As MMP-19 is able to degrade basement membrane constituents and other ECM proteins, it is conceivable that this relatively novel MMP family member contributes to MS pathology by remodelling the ECM of the CNS, thereby influencing leucocyte infiltration, axonal regeneration and astrogliosis.

Mucormycosis in a patient with low risk myelodysplasia treated with anti-TNF-alpha

Accelerated programmed cell death or apoptosis appears to play an important role in the pathogenesis of myelodysplasia. As overexpression of TNF-alpha has been described to induce cell death in myelodysplasia, treatment with anti-TNF-alpha is currently being explored. Caution is needed because of an increased risk of opportunistic infection during anti-TNF-alpha treatment. We here describe a patient who was treated with anti-TNF-alpha for low risk myelodysplasia and died of invasive mucormycosis.

Grey matter pathology in multiple sclerosis

Although multiple sclerosis (MS) has been considered a white matter disease, MS lesions are known to occur in grey matter. Recent immunohistochemical studies have demonstrated extensive grey matter demyelination in chronic MS. The most common lesion type consists of purely cortical lesions extending inward from the surface of the brain, this lesion subgroup is grossly underestimated by standard histochemical myelin staining methods. Some MS patients have subpial demyelination in all cortical areas of the brain; this pattern has been termed ''general cortical subpial demyelination''. Extensive cortical demyelination is associated with the progressive phases of disease, as less cortical demyelination has been detected in relapsing-remitting MS. The pathology of grey matter lesions differs from that of white matter lesions; grey matter lesions are less inflammatory, with less macrophage and lymphocyte infiltration. In purely cortical lesions there is no significant increase in lymphocytes compared with non-demyelinated adjacent cortical areas in MS patients or cerebral cortex in control patients. Significant axonal transection and neuronal loss have been demonstrated in grey matter MS lesions. Current magnetic resonance imaging (MRI) methods are not sensitive for purely cortical MS lesions. The clinical significance of cortical MS lesions may not be characterised until more sensitive MRI methods are developed.

Vascular colocalization of P-glycoprotein, multidrug-resistance associated protein 1, breast cancer resistance protein and major vault protein in human epileptogenic pathologies

Multidrug transporters, such as P-glycoprotein (P-gp), multidrug-resistance associated protein 1 (MRP1) and breast cancer resistance protein (BCRP), are associated with multidrug resistance in cancers; other molecules, such as major vault protein (MVP), have a similar association with drug-resistant cancer. These proteins are postulated to generate drug resistance in epilepsy. They have been shown individually to be up-regulated in epileptogenic brain tissue. In any consideration of the function, inhibition or evasion of the activity of such proteins, the colocalization of such proteins needs to be understood. We systematically determined the presence of such colocalization, focusing on microvascular endothelium from epileptogenic human brain tissue. Double labelling immunofluorescence and confocal laser scanning microscopy were used to determine colocalization of P-gp, MRP1, BCRP and MVP in one case of hippocampal sclerosis and two cases of focal cortical dysplasia type IIb. Endothelial colocalization was examined with double labelling using antibodies to CD34 and Factor VIII. The presence of P-gp, BCRP and MVP in microvascular endothelium was confirmed. P-gp, BCRP and MVP colocalized in microvascular endothelium, though not all proteins appeared to be identically distributed within this tissue. MRP1 did not colocalize to endothelium. These findings were not unexpected but required formal confirmation. The demonstrated colocalization of P-gp, BCRP and MVP in microvascular endothelium in epileptogenic human brain tissue has important implications for functional experiments (including single knock-out mice studies), work with specific and broad-spectrum inhibitors of transport function, and any eventual trials of treatment of refractory epilepsy involving modulation of the function of these proteins.

Economic evaluation of a comprehensive self-management programme in patients with moderate to severe chronic obstructive pulmonary disease

AIMS

The main objective of this study was to investigate whether a comprehensive self-management programme, including self-treatment guidelines for exacerbations and a fitness programme, is an efficient treatment option for chronic obstructive pulmonary disease (COPD) patients.

METHOD

We randomly allocated 248 COPD patients to either self-management (127) or usual care (121). Data on preference-based utilities (EuroQol-5D), health-related quality of life (HRQoL), health-care resource use and productivity losses associated with exacerbations were prospectively collected. Quality-adjusted life years (QALYs) were calculated. The economic analysis took the societal perspective and the observation period was one year.

RESULTS

As we observed that the groups were equally effective in terms of QALYs and HRQoL (SGRQ), we described a cost minimization analysis only. The self-management programme-specific costs amounted to Euro 642 per patient. In the base-case cost analysis, the incremental cost difference amounted to Euro 838 per patient per year in favour of usual care. When only direct medical costs were included, the incremental annual cost of self-management relative to usual care was Euro 179 per person per year. If time costs for the fitness programme were set to zero, the costs for self-management diminished to Euro 542. Sensitivity analysis showed that these results were robust to changes in the underlying assumptions.

CONCLUSION

We conclude that the COPE self-management programme is not an efficient treatment option for moderate to severe COPD patients who rate their HRQoL relatively high. The programme was twice as expensive as usual care and had no measurable beneficial effects on QALYs or HRQoL.

Cost effectiveness of inhaled steroid withdrawal in outpatients with chronic obstructive pulmonary disease

BACKGROUND

The evidence for the effectiveness and safety of inhaled corticosteroids (ICS) in chronic obstructive pulmonary disease (COPD) is inconclusive. This study determined the cost effectiveness of withdrawing fluticasone propionate (FP) in outpatients with COPD.

METHODS

The cost effectiveness analysis was based on a randomised, placebo controlled FP withdrawal study. After a 4 month run in period on FP, patients were randomly assigned to continue FP 500 microg twice daily or to receive placebo for 6 months. A decision analytical model evaluated the 6 month incremental cost effectiveness of the ICS versus ICS withdrawal strategy. One way sensitivity analyses and a Monte Carlo simulation were performed to evaluate the robustness of the findings.

RESULTS

The average patient with COPD in the FP group generated 511 in direct medical costs, including 238 for FP. The cost of the placebo strategy was 456. The higher direct drug cost of 212 per patient for the FP strategy during the 6 month follow up period compared with the placebo group was partially offset by a lower exacerbation and hospital admission cost of 157. The 6 month incremental cost effectiveness of the FP strategy compared with placebo was 110 per exacerbation prevented and 1286 per hospital admission prevented.

CONCLUSIONS

Over a 6 month period, withdrawing FP in a pre-selected trial population of COPD patients led to absolute cost savings but with a higher rate of exacerbations and hospital admissions.

Characteristics of 40 primary extranodal non-Hodgkin lymphomas of the oral cavity in perspective of the new WHO classification and the International Prognostic Index

Non-Hodgkin lymphomas (NHLs) are often present outside the lymph nodes. Although primary extranodal NHLs (PE-NHL) form a substantial part of all NHLs, reports on oral PE-NHLs are rare. Forty patients with PE-NHL of the oral cavity have been studied for the distribution of gender, age, oral subsite and presenting complaint, histological subtype according to the WHO classification, clinical stage, treatment, and follow-up. The data are reviewed against the background of the literature. Furthermore, the International Prognostic Index has been taken into consideration. All patients had a lymphoma of B-cell lineage. Two-thirds of patients presented with locoregional disease. Mean survival time was 38 months, with a mean recurrence-free survival time of 31 months. There was no statistically significant difference in survival time between patients with bone versus soft tissue localisation of the PE-NHL. In view of the rarity of PE-NHL involving the oral region multicenter studies are needed for evaluation of the usefulness of the International Prognostic Index for non-Hodgkin lymphoma in this particular part of the body.

Hypoxia-inducible factor-1alpha is associated with angiogenesis, and expression of bFGF, PDGF-BB, and EGFR in invasive breast cancer

AIMS

Hypoxia-inducible factor-1 (HIF-1) is the key transcription factor regulating the cellular response to hypoxia, including angiogenesis. Growth factors play an important role in tumour growth and angiogenesis and some have been shown to be induced by HIF-1 in vitro. This study investigated if angiogenesis or growth factors or their receptors are associated with HIF-1alpha in invasive breast cancer.

METHODS AND RESULTS

High levels of HIF-1alpha, detected by immunohistochemistry in 45 breast cancers, were positively associated with increased microvessel density (as a measure of angiogenesis) (P = 0.023). Furthermore, high levels of HIF-1alpha were associated with epithelial expression (> or = 10%) of epidermal growth factor receptor (EGFR) (P = 0.011), platelet-derived growth factor (PDGF)-BB (P < 0.001), and basic fibroblast growth factor (bFGF) (P = 0.045). A positive, yet insignificant, trend for HIF-1alpha to be associated with epithelial expression of transforming growth factor (TGF)-alpha (P = 0.081) and vascular endothelial growth factor (VEGF) (P = 0.109) was noticed as well as an inverse association with stromal expression of TGF-beta-R1 (P = 0.070).

CONCLUSIONS

In invasive breast cancer, HIF-1alpha is associated with angiogenesis, and expression of growth factors bFGF and PDGF-BB, and the receptor EGFR. Thus, agents targeting HIF-1 may combine different pathways of inhibiting breast cancer growth, including angiogenesis and growth factors.

Nuclear localization of survivin is a positive prognostic factor for survival in advanced non-small-cell lung cancer

BACKGROUND

Expression of survivin, a member of the inhibitor of apoptosis protein family, is commonly detected in cancers but not in normal differentiated tissues. Survivin is usually localized in the cytoplasm of cancer cells, but nuclear localization has also been described, and we recently reported that survivin is a nuclear-cytoplasmic shuttling protein.

PATIENTS AND METHODS

Fifty-three tumor specimens from patients with inoperable non-small-cell lung cancer (NSCLC) (55% stage IIIA, 17% stage IIIB and 28% stage IV) who underwent chemotherapy treatment were evaluated with immunohistochemistry for survivin expression and localization. These two sets of data were processed and tested for correlation with major patient characteristics, response to chemotherapy, and overall and relapse-free survival.

RESULTS

Survivin was present only in malignant tissues, and 47/53 (89%) of the specimens were positive. The overall median expression of tumor cells was 40%, and this value was used as a cut-off point for statistical analysis. By dichotomizing the specimens as expressing low or high levels of survivin, a significant association was seen between the expression of survivin and the histology of the tumors (P=0.020), squamous cell carcinoma being the histotype with lower levels of survivin expression. Three patterns of localization were observed: 42% of cases (22/53) showed reactivity confined to the nucleus, 17% (nine of 53) only in the cytoplasm and 30% (16/53) in both the nucleus and the cytoplasm. Interestingly, nuclear survivin levels predicted longer overall and relapse-free survival, in univariate and multivariate analyses. Expression and localization of survivin did not correlate with response to chemotherapy.

CONCLUSIONS

Our results indicate that differential localization of survivin may be a prognostic factor for NSCLC. Further studies are warranted.

Fluorine-18 fluorodeoxyglucose positron emission tomography (PET) to detect vital retinoblastoma in the eye: preliminary experience

BACKGROUND/AIMS

To report our first experience with FDG-PET in the detection of vital retinoblastoma.

METHODS

Four newly diagnosed retinoblastoma patients, two treated retinoblastoma patients, and four control patients were enrolled in this pilot study. F18-FDG uptake was assessed in the light of clinical and histopathological features.

RESULTS

PET discriminated between new patients and controls, although tumor uptake varied widely. PET added no useful information with regard to possible vital tissue in tumor scars in the eye of the two treated retinoblastoma patients. Moreover, PET findings did not correlate with clinical or histopathological features.

CONCLUSION

Based on this small pilot study, F18-PET shows little promise in the detection of retinoblastoma. More research on other radiofarmacons is recommended.

Neurotrophin receptor immunoreactivity in the hippocampus of patients with mesial temporal lobe epilepsy

Recent evidence supports a critical role of neurotrophins in the regulation of both neuronal survival and synaptic transmission during epileptogenesis. We have examined the immunohistochemical expression of high- (tyrosine kinase receptors, trk) and low-affinity (p75) neurotrophin receptors (NTRs) in the hippocampal specimens from 18 patients with chronic temporal lobe epilepsy [TLE; 14 patients with hippocampal sclerosis (HS) and four with focal lesions (tumours) not involving the hippocampus proper]. Nonepileptic autopsy brains (n = 6) and surgical specimens from tumour patients without epilepsy (n = 3) were used as controls. Immunoreactivity (IR) for the trk receptors (trkA, trkB, trkC) was detected in normal human brain within the pyramidal neurones of hippocampal cornus ammoni (CA) regions and in the dentate gyrus. There were no detectable differences in the neuronal trk IR patterns in the hippocampus between control and TLE cases with HS, except for a decrease in neuronal density in regions where cell death had occurred (CA1, CA3 and CA4). In contrast, a consistent increase in trkA IR was observed in reactive astrocytes in CA1 and dentate gyrus. The low-affinity p75 neurotrophin receptor (p75(NTR)) was expressed in low levels in postnatal normal hippocampus. In contrast, neuronal p75(NTR) IR was detected in 10/14 cases of HS in spared neurones within the CA and hilar regions of the hippocampus. Double labelling revealed that p75(NTR)-positive neurones also contain trk receptor IR. In six cases with prominent glial activation strong p75(NTR) IR was observed in microglial cells within the sclerotic hippocampus. The present results indicate that changes in NTR expression are still detectable in the hippocampus of patients with chronic TLE and involve both glial and neuronal cells. Reactive astrocytes were immunoreactive for trkA, whereas activated microglia cells were reactive for p75(NTR), suggesting different functions for specific NTRs in the development of reactive gliosis. Moreover, the increased expression of p75(NTR) in hippocampal neurones of TLE patients may critically influence the neuronal survival during the epileptogenic process.

ALK-negative anaplastic large-cell lymphoma demonstrates similar poor prognosis to peripheral T-cell lymphoma, unspecified

AIMS

Anaplastic large cell lymphoma (ALCL) is classically considered a clinicopathological entity separate from other nodal mature T-cell lymphomas (TCL). Recently, the anaplastic lymphoma kinase (ALK) protein was shown to identify a subgroup of nodal ALCL with an excellent prognosis, whereas ALK-negative ALCLs are more heterogeneous. The aim of this study was to investigate the clinicopathological parameters in relation to clinical behaviour of ALK-negative ALCL compared with other nodal mature TCL, i.e. peripheral TCL, unspecified (PTCL-NOS) and angioimmunoblastic lymphoma (AILT).

METHODS AND RESULTS

Clinicopathological data of ALK-positive (n = 28) and ALK-negative (n = 46) ALCL; PTCL-NOS (n = 47); and AILT (n = 12) were analysed for their prognostic significance. While ALK-positive ALCL shows favourable clinical features and a good prognosis, ALK-negative ALCL, PTCL-NOS and AILT are all associated with high age groups, advanced disease stage, and poor prognosis (<45% 5-year survival). In multivariate analysis of overall survival time, performed in the combined group of ALK-negative nodal mature T-cell lymphomas, only age and the International Prognostic Index (IPI) remained independent prognostic parameters, while lymphoma subtype (ALCL versus PTCL-NOS versus AILT) gave no additional information.

CONCLUSIONS

The distinction between ALK-negative ALCL and PTCL-NOS or AILT is of limited clinical relevance as they show comparable poor prognosis. In these lymphoma subtypes, only age and the IPI are of significant prognostic value.

Effects of a comprehensive self-management programme in patients with chronic obstructive pulmonary disease

The aim of this study was to assess the effects of a comprehensive self-management intervention on health-related quality of life (HRQoL), symptoms and walking distance in patients with stable moderately severe chronic obstructive pulmonary disease (COPD). This study was part of the overall COPD study of the Dept of Pulmonary Medicine, Enschede, which consisted of an inhaled corticosteroid (ICS) trial and a self-management trial. After the ICS trial, all patients were randomised again to a self-management and a control group. The self-management intervention consisted of a skill-oriented patient education programme and a near-home fitness programme, on top of usual care. The control group received usual care by the treating chest physician. HRQoL was measured by the St George's Respiratory Questionnaire (SGRQ) and walking distance by the 6-min walking test. Patients recorded their symptoms in diaries and graded their health status from 1-10 in a weekly report. Altogether, 248 COPD patients were randomly allocated to either an intervention (127) or control (121) group. No differences in the SGRQ scores within and between both groups were observed over 1 yr. Similarly, no differences in symptom scores and 6-min walking distance were found within and between groups. The intervention group reported more exacerbations than the control group. The majority (69%) of the exacerbations in the intervention group were self-treated at home. This study failed to show positive effects of a self-management programme among moderately severe chronic obstructive pulmonary disease patients.

Altered expression patterns of group I and II metabotropic glutamate receptors in multiple sclerosis

Recent evidence supports a role for glutamate receptors in the pathophysiology of multiple sclerosis. In the present study, we have focused specifically on the expression of metabotropic glutamate receptors (mGluRs) in multiple sclerosis brain tissue. The expression of group I (mGluR1alpha and mGluR5) and group II (mGluR2/3) mGluRs was studied using immunohistochemistry in tissue from 12 multiple sclerosis cases and seven non-neurological controls. The expression patterns of both group I and II mGluRs in multiple sclerosis tissue differed significantly from those in control tissue. Strong mGluR1alpha immunoreactivity was observed in axons of the subcortical white matter, particularly in the centre of actively demyelinating lesions and in the borders of chronic active lesions. mGluR1alpha axonal immunopositivity was also found in normal appearing multiple sclerosis white matter, but axons in control white matter were generally negative. mGluR1alpha axonal labelling was associated with the presence of non-phosphorylated neurofilaments and beta-amyloid precursor protein, which are sensitive markers for axonal injury and disturbed axonal transport. Changes in mGluR immunoreactivity were also observed in glia. A diffuse increase in the expression of mGluR5 and mGluR2/3 was detected in reactive astrocytes in multiple sclerosis lesions. However, only a subpopulation of reactive astroglial cells expressed mGluR1alpha. In addition, labelling with antibodies to mGluR2/3 and, to a lesser extent labelling with antibodies to mGluR1alpha, was detected in a population of cells of the microglial/macrophage lineage that displayed a macrophage-like morphology. Our data suggest that mGluRs, like ionotropic glutamate receptors, play a role in the complex processes that are associated with the progressive brain damage in multiple sclerosis, including both glial activation and pathological changes in axons.

Self-management education for patients with chronic obstructive pulmonary disease: a systematic review

BACKGROUND

The idea of self-management is to teach patients how to carry out the activities of daily living optimally in the face of their physiological impairment, and to prevent or decrease the severity of exacerbations by means of life style adaptation. In chronic obstructive pulmonary disease (COPD) the value of self-management education is not clear. This review was undertaken to clarify the effectiveness of self-management programmes in COPD.

METHODS

A search was made of the Cochrane Airways Group trial registers, Medline, reference lists, and abstracts of medical conferences for controlled trials of self-management education in patients with COPD. Two reviewers independently assessed each paper for methodological quality and extracted the data.

RESULTS

The reviewers included 12 articles describing eight randomised controlled trials and one controlled clinical trial in which self-management education was compared with usual care. The studies assessed a broad spectrum of outcome measures with different follow up times so meta-analysis could not be undertaken. Self-management education had no effect on hospital admissions, emergency room visits, days lost from work, and lung function. Inconclusive results were observed on health related quality of life, COPD symptoms, and use of healthcare facilities such as doctor and nurse visits. Self-management education reduced the need for rescue medication and led to increased use of courses of oral steroids and antibiotics for respiratory symptoms.

CONCLUSIONS

Insufficient data were obtained to make recommendations because of the wide variation in outcome measures used and other limitations to generalisations in the current published literature. Further research in this area is needed.

Comparative genomic hybridisation divides retinoblastomas into a high and a low level chromosomal instability group

BACKGROUND

Retinoblastoma is the most common intraocular malignancy in childhood and is responsible for approximately 1% of all deaths caused by childhood cancer.

AIMS/METHODS

Comparative genomic hybridisation was performed on 13 consecutive, histologically confirmed retinoblastomas to analyse patterns of chromosomal changes and correlate these to clinicopathological variables. Six cases were hereditary and seven cases were sporadic.

RESULTS

In 11 of the 13 tumours chromosomal abnormalities were detected, most frequently gains. Frequent chromosomal gains concerned 6p (46%), 1q (38%), 2p, 9q (30%), 5p, 7q, 10q, 17q, and 20q (23%). Frequent losses occurred at Xq (46%), 13q14, 16q, and 4q (23%). High level copy number gains were found at 5p15 and 6p11-12. A loss at 13q14 occurred in three cases only. Relatively few events occurred in the hereditary cases (27) compared with the non-hereditary cases (70 events). The number of chromosomal aberrations in these 13 retinoblastomas showed a bimodal distribution. Seven tumours showed less than four chromosomal aberrations, falling into a low level chromosomal instability (CIN) group, and six tumours showed at least eight aberrations, falling into a high level CIN group. In the low level CIN group the mean age was half that seen in the high level CIN group, there were less male patients, and there were more hereditary and bilateral cases. Microsatellite instability was not detected in either of the two groups.

CONCLUSION

Despite the complex pattern of genetic changes in retinoblastomas, certain chromosomal regions appear to be affected preferentially. On the basis of the number of genetic events, retinoblastomas can be divided in low and a high level chromosomal instability groups, which have striking differences in clinical presentation.

Axonal damage in the spinal cord of MS patients occurs largely independent of T2 MRI lesions

OBJECTIVE

To determine the degree of axonal damage in relationship to signal abnormalities on T2-weighted high-resolution MRI in spinal cord tissue of patients with MS.

METHODS

Spinal cord specimens of nine patients with MS and four controls were imaged at high resolution (4.7 T) in an axial plane and scored for lesions with increased signal intensity (SI). Histopathologic sections were cut and immunostained with NE14 (neurofilament marker) and Luxol fast blue (myelin stain). For each area, axonal density and diameter were quantified; axonal irregularity, NE14 axonal staining intensity, and myelin content were semiquantitatively scored. Included were 209 areas from MS cases and 109 areas from control cases distributed over lateral, posterior, and anterior columns.

RESULTS

In control cases, no SI changes were found, average density of axons was 26,989/mm(2), average diameter was 1.1 micro m, and all scores for axonal irregularity, NE14 staining intensity, and myelin were normal. In MS cases, areas with increased SI were found, average axonal density was 11,807/mm(2) (p < 0.0001), and average axonal diameter 2.0 micro m (p = 0.001). Areas with high SI on MRI had lowest axonal density (average count: 10,504/mm(2); range: 3,433 to 26,325/mm(2)), largest diameter (average: 2.3 micro m; range: 1.0 to 4.0 micro m), and highest axonal irregularity and NE14 staining intensity compared to normal appearing cord tissue (NACT). However, NACT of MS cases also had lower axonal density (14,158/mm(2)) and higher average axonal diameter (1.6 micro m) than controls.

CONCLUSIONS

Marked axonal loss occurs in MS spinal cords, largely independent of the degree of signal abnormality on T2-weighted MRI.

[Diagnostic image (117). A man with frequent blood transfusion and blister on his fingers. A form of porpheria cutanea tarda caused by excess iron]

A 70-year-old man with primary myelofibrosis was treated with hydroxycarbamide and blood transfusions. He developed porphyria cutanea tarda.