Preclinical models for neuroblastoma: Advances and challenges.

Neuroblastoma is a paediatric cancer of the sympathetic nervous system and the most common solid tumour of infancy, contributing to 15% of paediatric oncology deaths. Current therapies are not effective in the long-term treatment of almost 80% of patients with this clinically aggressive disease. The primary challenge in the identification and validation of new agents for paediatric drug development is the accurate representation of tumour biology and diversity. In addition to this limitation, the low incidence of neuroblastoma makes the recruitment of eligible patients for early phase clinical trials highly challenging and highlights the need for robust preclinical testing to ensure that the best treatments are selected. The research field requires new preclinical models, technologies, and concepts to tackle these problems. Tissue engineering offers attractive tools to assist in the development of three-dimensional (3D) cell models using various biomaterials and manufacturing approaches that recreate the geometry, mechanics, heterogeneity, metabolic gradients, and cell communication of the native tumour microenvironment. In this review, we discuss current experimental models and assess their abilities to reflect the structural organisation and physiological conditions of the human body, in addition to current and new techniques to recapitulate the tumour niche using tissue-engineered platforms. Finally, we will discuss the possible use of novel 3D in vitro culture systems to address open questions in neuroblastoma biology.

Staging of squamous cell carcinoma of the tongue: extrinsic lingual muscles and the 8th editions of the American Joint Committee on Cancer/Union for International Cancer Control staging manuals.

Our aim was to find out first whether the extrinsic muscles of the tongue are histologically identifiable, and secondly to what degree the use of the new criteria in the 8th editions of the American Joint Committee on Cancer(AJCC)/Union for International Cancer Control (UICC) manuals (which have recognised the importance of depth of invasion of tumour, rather than invasion of the extrinsic muscles of the tongue and extranodal extension), will alter staging of lingual squamous cell carcinoma (SCC). The histological sections from 165 patients who had had primary resection of lingual SCC were reviewed, and one or more extrinsic muscles of the tongue was identified in 100 patients (61%), with the genioglossus seen the most often (in 96). By contrast, the hyoglossus was identified in only eight patients, the styloglossus in two, and the palatoglossus in none. Identification was straightforward only in extensive resections. Applying the criteria from the 8th edition increased the number of pT3 SCC with a simultaneous reduction in pT4a tumours. The number of pN2b SCC was also reduced, but the new category of pN3b meant that overall 53% of tumours were upstaged. The kappa scores for agreement between the two sets of criteria were 0.221 (weighted 0.410) for the pT values, 0.508 (0.713) for pN values (but 0.227, weighted 0.386, if the pN0 values were removed before calculation), and 0.243 (0.514) for overall stage, indicating poor to fair agreement. We conclude that the removal of invasion of extrinsic muscles of the tongue as a criterion for a pT4a SCC is justified, and that many SCC of the tongue will be upstaged as a result of implementation of the 8th editions.

Orofacial plasmacytosis: a management conundrum.

Plasmacytosis of the mucous membrane is a rare, benign, inflammatory condition of poorly understood aetiology that affects the mucous membranes. Most reported cases involve the gingival tissues, larynx, and occasionally the lips. We describe an interesting case of orofacial plasmacytosis that affected the lower lip, mandibular gingiva, and buccal mucosa. It mimicked an oral squamous cell carcinoma and presented a management dilemma.

Fractalkine (CX3CL1) and fractalkine receptor (CX3CR1) in squamous cell carcinoma of the tongue: markers of nerve invasion?

PURPOSE: Perineural invasion (PNI) in oral squamous cell carcinoma (SCC) is an independent predictor of poor prognosis. As PNI is not always identified with routine histology, a surrogate marker of PNI would improve detection and better inform treatment planning. The chemokines fractalkine (CX3CL1) and its receptor (CX3CR1) have shown such potential in other cancers, but have yet to be investigated with respect to PNI in oral SCC. METHODS: Thirty SCCs of the tongue in which PNI was identified histologically, and 30 in which it was not, were stained for fractalkine and fractalkine receptor using polyclonal antibodies and an immunoperoxidase technique. Tumours were assessed as either positive or negative; no attempt was made to subjectively assess staining intensity or extent. RESULTS: Both markers labelled myofibroblasts in the stroma surrounding the tumour, various neural components, leucocytes, endothelium and salivary myoepithelial cells. Fractalkine also labelled salivary ductal epithelium, vascular smooth muscle and 12/30 SCC which showed PNI. Eight of 30 positive SCCs in which PNI was not identified were also positive for this marker. There was no statistically significant association between fractalkine staining and PNI (p = 0.273). No SCC was positive for fractalkine receptor, but immune dendritic cells within tumour islands were strongly positive, as was striated muscle. CONCLUSIONS: Neither fractalkine nor fractalkine receptor is a reliable surrogate marker of PNI in lingual SCC.

Hemimandibulectomy and vascularized fibula flap in bisphosphonate-induced mandibular osteonecrosis with polycythaemia rubra vera.

This report presents the successful management of an advanced and refractory bisphosphonate-related osteonecrosis of the jaws (BRONJ) by hemimandibulectomy and an osteocutaneous fibula flap reconstruction in a patient with polycythaemia rubra vera, a rare haematological condition in which there is increased risk of thrombosis and haemorrhage. Union of the vascularized bone with the mandible depends on obtaining a BRONJ-free margin and rigid fixation of the bony ends. Magnetic resonance imaging can provide accurate delineation of necrotic bone and area of osteomyelitis. Placement of a 1cm margin beyond this can envisage a BRONJ-free margin. Aggressive medical management of polycythaemia rubra vera by venesection, asprin and cytoreduction therapy along with anticoagulant prophylaxis against thromboembolic events in the first 2 weeks following major surgery can provide the basis of a good surgical and flap outcome. Nevertheless, the possibility of unpredictable haemorrhage must be considered throughout.

Navigation-assisted localisation and resection of subclinical metastatic malignant melanoma of unknown primary based on 18-fluorodeoxyglcose positron emission tomography computed tomography fusion imaging.

A technical application using a stereotactic navigation system with fusion images of [18F]-2-fluorodeoxyglucose (FDG) positron tomography and computed tomography (PET-CT) in the case of a metastatic melanoma of unknown primary site is described. A 50-year-old woman presented with a slow, growing level V neck lump which was cytologically proved to be a metastatic melanoma despite the absence of prior or existing history of skin malignancy. Whilst detailed physical examination failed to yield the site of the primary lesion, full body FDG-PET images isolated FDG-avid subclinical scalp lesions. Fused PET-CT data provided the navigation system with accurate localisation of the subclinical metastatic lesion. Histopathological examination of the navigation-guided resection specimen confirmed that the lesion was excised with acceptable margins. This case illustrates the feasibility of navigation-assisted resection of a subclinical malignant melanoma lesion and may have a role to play in the management of the melanoma of unknown primary.

United Kingdom myeloma forum position statement on the use of lenalidomide in multiple myeloma.

Lenalidomide is an immunomodulatory drug, which has anti-myeloma activity in vitro. Phase II clinical trials have demonstrated lenalidomide in combination with dexamethasone is effective for the treatment of both relapsed refractory myeloma and newly diagnosed patients. Two large phase III studies comparing lenalidomide and dexamethasone to dexamethasone alone in relapsed patients showed superiority in response, progression free and overall survival. It is administered orally for 21 days in a 28 day cycle. Side effects are manageable and include neutropenia and venous thrombotic events. It is currently approved, in combination with dexamethasone, for the treatment of multiple myeloma patients who have received at least one prior therapy. Studies in front line patients and with other drug combinations are ongoing. Given the strength of this data the UK Myeloma Forum believe that lenalidomide in combination with dexamethasone should be available for prescription by UK haematologists according to its licensed indication in patients with relapsed myeloma.

Bilateral intraparotid and extraparotid Warthin's tumours.

Warthin's tumour is a benign adenoma in the parotid gland, but extraparotid and synchronous bilateral Warthin's tumours may occur. In this report, we describe a patient with simultaneous bilateral involvement of the parotid glands and neck by multiple Warthin's tumours, an occurrence not previously described.

Repeat ABO-incompatible platelet transfusions leading to haemolytic transfusion reaction.

A 65-year-old woman, blood group A RhD positive, who had completed her first course of induction chemotherapy for acute myeloid leukaemia was transfused with apheresis platelets over a number of days. On three occasions she received group O RhD positive units, which had been screened and found not to contain high-titre anti-A,B isoagglutinins. Following the third unit, she developed a haemolytic transfusion reaction and died soon thereafter. This has led to change in policy of the supplying centre in testing for high-titre anti-A,B isoagglutinins. Blood group O apheresis platelets and fresh-frozen plasma units are now labelled as high titre with a cut-off of 1/50 as compared to the previous cut-off of 1/100 for anti-A,B isoagglutinins. A universal approach to testing donations for high-titre anti-A,B isoagglutinins, better compliance of guidelines and monitoring of patients is necessary.

Sensory and motor function impairment after brachial plexuscord compression by a pedicled latissimus dorsi flap.

A case of neuropraxia of the sensory and motor nerve fibres of the brachial plexus is reported after successful transfer of an ipsilateral pedicled myocutaneous latissimus dorsi flap to reconstruct a large-volume tissue defect in the neck resulting from a shotgun injury.

Specificity of Doppler echocardiography for the assessment of changes in valvular regurgitation: comparison of side-by-side versus serial interpretation.

OBJECTIVES: We sought to determine the specificity of two different methods for assessing change in aortic (AR), mitral (MR) and tricuspid (TR) valvular regurgitation. BACKGROUND: Echocardiographic imaging with Doppler is the standard noninvasive diagnostic tool for assessing valvular structure and function. Change can be assessed using either independent evaluations (serial) or using a side-by-side comparison. METHODS: Subjects were from the placebo arm of a randomized, double-blind, clinical trial. Three echocardiograms over 10 months were performed. An initial and three-month echocardiogram were read as independent groups, blinded to all parameters except sequence. The initial and 10-month echocardiograms were read side-by-side, blinded to all parameters including sequence. RESULTS: Two hundred nineteen predominantly healthy, obese, white, middle-aged women had initial and three-month echocardiograms (acquisition interval 105 +/- 28 days) evaluated by the serial method (mean 167 +/- 61 days between interpretations). The same subjects had the initial and 10-month studies (acquisition interval 303 +/- 27 days) compared side-by-side. The specificity of the serial versus side-by-side method for determining change in MR grade was 55.8% versus 93.2% (p < 0.001); TR: 63.8% versus 97.6% (p < 0.001) and AR: 93.7% versus 97.6 (p = 0.08). Notably, most of the change occurred in a range (none versus physiologic/mild) that has limited clinical significance. Furthermore, the percentage of echocardiograms interpreted as nonevaluable was lower with the side-by-side method for MR (5.0% vs. 16.0%, p = 0.06), TR (4.6% vs. 15.5%, p < 0.001) and AR (4.1% vs. 12.3%, p = 0.002). CONCLUSIONS: The side-by-side method of assessing change in valvular regurgitation appears to be the more reliable method with a higher specificity and minimal data loss.

Cleft posterior mitral valve leaflet associated with counterclockwise papillary muscle malrotation.

Isolated clefting of the posterior mitral valve leaflet is an uncommon congenital malformation. We report a case of cleft posterior mitral valve leaflet with counterclockwise papillary muscle malrotation. Similar abnormalities in papillary muscle position have been described in association with atrioventricular septal defect but have not been previously reported accompanying isolated clefting of the posterior mitral valve leaflet.

Natural history of valvular regurgitation 1 year after discontinuation of dexfenfluramine therapy. A randomized, double-blind, placebo-controlled trial.

BACKGROUND: Previous studies have reported small increases in the prevalence of low-grade aortic and mitral regurgitation in patients treated with dexfenfluramine compared with placebo. However, whether valvular abnormalities develop or progress 1 year after discontinuation of dexfenfluramine therapy has not been determined. OBJECTIVE: To assess change in valvular regurgitation and morphologic characteristics 1 year after discontinuation of dexfenfluramine therapy. DESIGN: Randomized, double-blind, placebo-controlled, multicenter study. SETTING: Outpatient obesity centers. PATIENTS: Obese persons who had been treated for 2 to 3 months with dexfenfluramine, sustained-release dexfenfluramine, or placebo. Blinding was maintained, and patients returned for repeated echocardiography at 1 year. MEASUREMENTS: Pairs of echocardiograms were evaluated with a side-by-side reading method for change in grade of valvular regurgitation, structure, and function. A standardized acquisition and reading protocol was followed, and a core laboratory was used. RESULTS: 914 patients who had initial echocardiography returned for repeated echocardiography 11.4 +/- 1.0 months (mean +/- SD) after discontinuing study medication (10.0 +/- 1.0 months after initial echocardiography). Compared with the placebo group, a greater proportion of patients in both dexfenfluramine groups had decreased aortic regurgitation (P = 0.003 for the dexfenfluramine group, P = 0.02 for the sustained-release group). No change in mitral regurgitation or any other measure of valvular structure or function was seen in any treatment group. CONCLUSIONS: After dexfenfluramine therapy is taken for 2 to 3 months and discontinued, development or progression of any valvular regurgitation over the following year is unlikely. Echocardiographic evidence suggests that aortic regurgitation regresses in some previously treated patients.

Myeloid leukaemic cells can lyse fibrin directly.

Purified preparations of circulating leukaemic blast cells from patients with acute myeloid (M1-7) or acute lymphoblastic leukaemia, and the myeloid or lymphoid cells from patients with chronic myeloid or lymphocytic forms of leukaemia, were incorporated into clots prepared from fibrinogen and plasminogen. Patterns of lysis were followed and measured by light transmission in a microtitre plate reader. Mature polymorphonuclear and mononuclear cell fractions from normal individuals were studied concurrently for comparison. Blast cells from the myeloid forms of acute leukaemia (M2-4) and 'myeloid' cell fractions from patients with chronic myeloid leukaemia were capable of lysing plasminogen-containing clots; this activity was neutralized by addition of immunoglobulin against urokinase plasminogen activator (u-PA), but not by anti-tissue plasmogen activator (t-PA). Mature polymorphonuclear and mononuclear cells from normal individuals lacked lytic activity, as did the leukaemic cells from patients with acute lymphoblastic or chronic lymphocytic leukaemia. Lysed blast cells showed the presence of free plasminogen activator on sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) with overlay zymography, also neutralized by anti-u-PA, whereas normal polymorphonuclear and mononuclear cells did not. These observations suggest that mechanisms underlying some forms of severe bleeding in acute myeloid leukaemias have a critical fibrinolytic component generated by the blast cells themselves.

Confidentiality and adolescents' use of providers for health information and for pelvic examinations.

OBJECTIVE: To examine the relationship between adolescents' perception of the confidentiality of care provided by their regular health care provider and their reported use of this provider for private health information and for pelvic examinations. DESIGN: Anonymous, self-report survey. SETTING: Thirty-two randomly selected public high schools in Massachusetts. PARTICIPANTS: Of 2224 students in systematically selected 9th and 12th grade classrooms, 1715 (50% male) had a regular provider and a checkup within the last year. RESULTS: Of teens surveyed, 76% wanted the ability to obtain confidential health care, but only 45% perceived their regular provider to provide this, and only 28% had discussed it explicitly. Logistic regression analyses revealed strong relationships between confidentiality and all outcomes studied. Among adolescents, the likelihood of having discussed sexually transmitted diseases, pregnancy prevention, and/or facts about sex with their provider was greater among teens who received a confidentiality assurance than that for teens who did not (odds ratio [OR] = 2.7; 95% confidence interval [CI], 2.2-3.4). A similar relationship for teens' likelihood of having discussed substance use with the provider was found (OR = 1.8; 95% CI, 1.4-2.3). Among sexually active females, the likelihood of a recent pelvic examination for those who received a confidentiality assurance was greater than for those who did not (OR = 3.3; 95% CI, 2.1-5.5). CONCLUSIONS: This study furthers evidence of an important link between teens' perception of confidentiality and use of health care services and information. Because teens' health risks lie largely in potential risks from health-related behaviors, confidentiality in health care may be a critical factor in disclosure and discussion of risky behaviors, and ultimately in appropriate use of health care services. Efforts should be made to increase teens' access to confidential health care sources.

A minor salivary gland tumour presenting with dysphagia.

A case is reviewed of a giant benign myoepithelioma of the soft palate presenting in an elderly female patient. Due to the large size of the lesion and its mass effect the patient developed dysphagia with subsequent significant weight loss. The clinico-pathological features of this rare tumour are described and the literature reviewed.

Prevalence of valvular-regurgitation associated with dexfenfluramine three to five months after discontinuation of treatment.

OBJECTIVES: The goal of this study was to determine the prevalence of valvular regurgitation and abnormal valve morphology in patients three to five months after discontinuation of dexfenfluramine (Dexfen) therapy. BACKGROUND: We previously reported the results of a randomized, double-blind, placebo-controlled trial of valvular structure and function in 1,073 patients treated either with Dexfen, with an investigational sustained-release dexfenfluramine (Dexfen SR), or with a placebo, with echocardiograms performed approximately one month from the last dose. Using FDA criteria (aortic regurgitation [AR] > or =mild and/or mitral regurgitation [MR] > or =moderate) we found no statistical difference among the groups, but when all degrees of valvular regurgitation were considered and when the two Dexfen groups were combined, there was a higher prevalence of any degree of AR, any degree of MR, and restricted posterior mitral leaflet mobility. However, it was unknown whether these differences in prevalence persisted. METHODS: The double blind was maintained, and all patients were invited to return for a follow-up echocardiogram. Echocardiograms were acquired using a standardized protocol and assessed blindly to determine the degree of valvular regurgitation and valve leaflet thickness and mobility. We had an 80% power to detect a statistically significant change in paired proportions using the McNemar test (alpha = 0.05). RESULTS: Echocardiograms were obtained on 941 patients with a median of 137 days after drug discontinuation. Aortic regurgitation (of any degree) was present in 13.8% of Dexfen (p = 0.41 compared to placebo), 10.7% of Dexfen SR (p = 0.64 compared to placebo), and 11.9% of placebo patients. The minor differences between patients treated with active drug versus placebo, which were found in the previous study, were no longer significant even when the groups were combined (p = 0.83 compared to placebo). Mitral regurgitation (of any degree) was present in 71.5% (p = 0.15 compared to placebo), 69.8% (p = 0.30 compared to placebo), and 70.5%, respectively. This was also not significantly different from placebo when both Dexfen groups were combined (p = 0.16). There was no difference in the prevalence of restricted posterior mitral leaflet mobility among the three groups (p = 0.19). CONCLUSIONS: The small increase in prevalence of minor degrees of AR and MR in patients treated with two to three months of Dexfen previously reported is no longer present three to five months after discontinuation of medication. These data suggest that the degree of regurgitation observed in patients who used Dexfen for a relatively short duration does not progress over time.