Lapatinib dysregulates HER2 signaling and impairs the viability of human uveal melanoma cells

Uveal melanoma (UM) is the principal type of intraocular malignancy in adults. Up to 50% of UM patients develop metastatic disease with very poor survival. There are few drugs available to treat the primary or metastatic UM. This study was undertaken to evaluate the anti-cancer effect of lapatinib and corroborate the potential of HER2 inhibition in the treatment of UM. The anti-UM activity of lapatinib was assessed using cell viability, cell death and cell cycle analysis, and its anti-metastatic actions were evaluated using would healing, invasion and colony formation assays. Immunoblotting was used to substantiate the actions of lapatinib on apoptotic and HER2 signaling. The anti-UM activity of lapatinib was further evaluated in a UM xenograft mouse model. Lapatinib decreased the viability of four UM cell lines (IC50: 3.67-6.53 µM). The antiproliferative activity of lapatinib was corroborated in three primary cell lines isolated from UM patient tumors. In UM cell lines, lapatinib promoted apoptosis and cell cycle arrest, and strongly inhibited cell migration, invasion and reproductive cell growth. Lapatinib dysregulated HER2-AKT/ERK/PI3K signalling leading to the altered expression of apoptotic factors and cell cycle mediators in UM cell lines. Importantly, lapatinib suppressed tumourigenesis in mice carrying UM cell xenografts. Together the present findings are consistent with the assertion that HER2 is a viable therapeutic target in UM. Lapatinib is active in primary and metastatic UM as a clinically approved HER2 inhibitor. The activity of lapatinib in UM patients could be evaluated in future clinical trials.

The multifunctional human ocular melanocortin system

Immune privilege in the eye involves physical barriers, immune regulation and secreted proteins that together limit the damaging effects of intraocular immune responses and inflammation. The neuropeptide alpha-melanocyte stimulating hormone (α-MSH) normally circulates in the aqueous humour of the anterior chamber and the vitreous fluid, secreted by iris and ciliary epithelium, and retinal pigment epithelium (RPE). α-MSH plays an important role in maintaining ocular immune privilege by helping the development of suppressor immune cells and by activating regulatory T-cells. α-MSH functions by binding to and activating melanocortin receptors (MC1R to MC5R) and receptor accessory proteins (MRAPs) that work in concert with antagonists, otherwise known as the melanocortin system. As well as controlling immune responses and inflammation, a broad range of biological functions is increasingly recognised to be orchestrated by the melanocortin system within ocular tissues. This includes maintaining corneal transparency and immune privilege by limiting corneal (lymph)angiogenesis, sustaining corneal epithelial integrity, protecting corneal endothelium and potentially enhancing corneal graft survival, regulating aqueous tear secretion with implications for dry eye disease, facilitating retinal homeostasis via maintaining blood-retinal barriers, providing neuroprotection in the retina, and controlling abnormal new vessel growth in the choroid and retina. The role of melanocortin signalling in uveal melanocyte melanogenesis however remains unclear compared to its established role in skin melanogenesis. The early application of a melanocortin agonist to downregulate systemic inflammation used adrenocorticotropic hormone (ACTH)-based repository cortisone injection (RCI), but adverse side effects including hypertension, edema, and weight gain, related to increased adrenal gland corticosteroid production, impacted clinical uptake. Compared to ACTH, melanocortin peptides that target MC1R, MC3R, MC4R and/or MC5R, but not adrenal gland MC2R, induce minimal corticosteroid production with fewer amdverse systemic effects. Pharmacological advances in synthesising MCR-specific targeted peptides provide further opportunities for treating ocular (and systemic) inflammatory diseases. Following from these observations and a renewed clinical and pharmacological interest in the diverse biological roles of the melanocortin system, this review highlights the physiological and disease-related involvement of this system within human eye tissues. We also review the emerging benefits and versatility of melanocortin receptor targeted peptides as non-steroidal alternatives for inflammatory eye diseases such as non-infectious uveitis and dry eye disease, and translational applications in promoting ocular homeostasis, for example, in corneal transplantation and diabetic retinopathy.

The multi-kinase inhibitor afatinib serves as a novel candidate for the treatment of human uveal melanoma

PURPOSE

Uveal melanoma (UM) is the most common intraocular malignancy in adults with a poor prognosis and a high recurrence rate. Currently there is no effective treatment for UM. Multi-kinase inhibitors targeting dysregulated pro-tumorigenic signalling pathways have revolutionised anti-cancer treatment but, as yet, their efficacy in UM has not been established. Here, we identified the multi-kinase inhibitor afatinib as a highly effective agent that exerts anti-UM effects in in vitro, ex vivo and in vivo models.

METHODS

We assessed the anti-cancer effects of afatinib using cell viability, cell death and cell cycle assays in in vitro and ex vivo UM models. The signaling pathways involved in the anti-UM effects of afatinib were evaluated by Western blotting. The in vivo activity of afatinib was evaluated in UM xenograft models using tumour mass measurement, PET scan, immunohistochemical staining and TUNEL assays.

RESULTS

We found that afatinib reduced cell viability and activated apoptosis and cell cycle arrest in multiple established UM cell lines and in patient tumour-derived primary cell lines. Afatinib impaired cell migration and enhanced reproductive death in these UM cell models. Afatinib-induced cell death was accompanied by activation of STAT1 expression and downregulation of Bcl-xL and cyclin D1 expression, which control cell survival and cell cycle progression. Afatinib attenuated HER2-AKT/ERK/PI3K signalling in UM cell lines. Consistent with these observations, we found that afatinib suppressed tumour growth in UM xenografted mice.

CONCLUSION

Our data indicate that afatinib activates UM cell death and targets the HER2-mediated cascade, which modulates STAT1-Bcl-xL/cyclin D1 signalling. Thus, targeting HER2 with agents like afatinib may be a novel therapeutic strategy to treat UM and to prevent metastasis.

Congenital Hypertrophy of the Retinal Pigment Epithelium (CHRPE) as a Screening Marker for Familial Adenomatous Polyposis (FAP): Systematic Literature Review and Screening Recommendations

Purpose

Familial adenomatous polyposis (FAP) has an almost 100% colorectal cancer risk warranting early detection in gene carriers. This study presents congenital hypertrophy of the retinal pigment epithelium (CHRPE) as a highly specific phenotypical marker for FAP that can be used in screening at-risk individuals. Screening recommendations including morphological subclassification were formulated with supporting literature.

Methods

A systematic literature review with a comprehensive search strategy was conducted using online databases. Manual searches of bibliographies and reference lists were also performed. Studies meeting inclusion criteria were graded with respect to their hierarchy of evidence and strength of recommendations according to the National Health and Medical Research Council (NHMRC) guidelines of Australia.

Results

Almost 4500 participants were analysed across 28 included studies. The mean specificity of CHRPE as a phenotypical screening marker of FAP was 89% (standard deviation (SD); 14) with a mean sensitivity of 79% (SD; 8). The mean prevalence of CHRPE amongst FAP participants; at-risk participants were found to be 76% (SD; 24) and 37% (SD; 21) respectively. Bilateralism and multiple lesion number ≥3 are features highly specific for FAP.

Conclusion

CHRPE was found to be a non-invasive, rapid, early phenotypical screening marker of FAP. Clinical recognition further allows increased gene analysis efficiency. The absence of CHRPE alone cannot exclude FAP. Our screening recommendations provide guidance to clinicians on evidence based CHRPE assessment. We would advocate inclusion of ocular examinations as part of a three-pronged approach, along with endoscopy and genetic testing, for efficient, timely FAP assessment in at-risk individuals.

Analysis of Circulating Tumour Cells in Early-Stage Uveal Melanoma: Evaluation of Tumour Marker Expression to Increase Capture

(1) Background: The stratification of uveal melanoma (UM) patients into prognostic groups is critical for patient management and for directing patients towards clinical trials. Current classification is based on clinicopathological and molecular features of the tumour. Analysis of circulating tumour cells (CTCs) has been proposed as a tool to avoid invasive biopsy of the primary tumour. However, the clinical utility of such liquid biopsy depends on the detection rate of CTCs. (2) Methods: The expression of melanoma, melanocyte, and stem cell markers was tested in a primary tissue microarray (TMA) and UM cell lines. Markers found to be highly expressed in primary UM were used to either immunomagnetically isolate or immunostain UM CTCs prior to treatment of the primary lesion. (3) Results: TMA and cell lines had heterogeneous expression of common melanoma, melanocyte, and stem cell markers. A multi-marker panel of immunomagnetic beads enabled isolation of CTCs in 37/43 (86%) patients with UM. Detection of three or more CTCs using the multi-marker panel, but not MCSP alone, was a significant predictor of shorter progression free (p = 0.040) and overall (p = 0.022) survival. (4) Conclusions: The multi-marker immunomagnetic isolation protocol enabled the detection of CTCs in most primary UM patients. Overall, our results suggest that a multi-marker approach could be a powerful tool for CTC separation for non-invasive prognostication of UM.

Development of new therapeutic options for the treatment of uveal melanoma

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults. Important cytogenetic and genetic risk factors for the development of UM include chromosome 3 monosomy, mutations in the guanine nucleotide-binding proteins GNAQ/GNA11, and loss of the BRACA1-associated protein 1 (BAP 1). Most primary UMs are treated conservatively with radiotherapy, but enucleation is necessary for large tumours. Despite the effectiveness of local control, up to 50% of UM patients develop metastasis for which there are no effective therapies. Attempts to utilise the targeted therapies that have been developed for the treatment of other cancers, including a range of signal transduction pathway inhibitors, have rarely produced significant outcomes in UM. Similarly, the application of immunotherapies that are effective in cutaneous melanoma to treat UM have also been disappointing. Other approaches that have been initiated involve proteasomal inhibitors and histone deacetylase inhibitors which are approved for the treatment of other cancers. Nevertheless, there have been occasional positive outcomes from these treatments in UM. Moreover, combination approaches in UM have also yielded some positive developments. It would be valuable to identify how to apply such therapies efficiently in UM, potentially via individualised tumour profiling. It would also be important to characterise UM tumours to differentiate the potential drivers of progression from those in other types of cancers. The recent identification of novel kinases and metastatic genes in UM tumours makes the development of new UM-specific treatments feasible.

Germline BAP1-positive patients: the dilemmas of cancer surveillance and a proposed interdisciplinary consensus monitoring strategy

The germline BAP1 (BRCA1-associated protein-1) mutation and associated cancer pre-disposition syndrome was first described in 2011. Since then, physicians have considered this diagnosis for patients with a characteristic personal or family history of BAP1-associated tumours (mainly uveal and cutaneous melanoma, pleural/peritoneal mesothelioma, renal cell carcinoma and BAP1-deficient melanocytic lesions). However, a positive germline BAP1 mutation detection creates significant uncertainty in terms of appropriate cancer surveillance. A number of groups have proposed surveillance plans but important management dilemmas remain unresolved. The lifetime risk of developing cancer is not known and it is not clear if surveillance would lead to detecting cancer at an earlier stage or change survival outcomes. A consensus monitoring strategy was initially proposed at the Melanoma Institute Australia Melanoma Multidisciplinary Team meeting and later discussed with specialists in the field of cancer genetics, pathology, radiology, medical oncology, ophthalmology and dermatology. The objectives were to facilitate early diagnosis, incorporating where possible, clinically based and low/non-ionising radiation imaging modalities, applying the principles of a good screening test and a multidisciplinary focus.

Conjunctival melanoma: a review of conceptual and treatment advances

The aim of this study was to review the available literature and identify recent advances in the classification and management of conjunctival melanoma (CM) for clinicians working in this field. English-based articles were identified using the MEDLINE^® database, and additional cited works not detected in the initial search were also obtained. Articles were assessed according to the Australian National Health and Medical Research Council levels of evidence criteria. Review of the literature indicated that the current classification and management of CM is predominantly based upon primarily nonrandomized, single-institution, retrospective case series. While these studies provide the basis for the recent seventh edition of the tumor node metastasis staging classification, this classification more accurately reflects the current knowledge of prognostic factors for CM. Application of this revised classification system together with prospective trials will provide the opportunity for future consistent and comparable data collection across centers, and it will improve the quality of evidence upon which current classification and management of CM is based. Furthermore, the high risk of local recurrence with current standard management suggests that adjuvant therapy, particularly mitomycin C and/or brachytherapy, may improve outcomes regardless of clinical staging. Finally, the use of sentinel lymph node biopsy may have significant benefit for a select group of CM patients.

Expression of cancer-testis antigens (MAGE-A1, MAGE-A3/6, MAGE-A4, MAGE-C1 and NY-ESO-1) in primary human uveal and conjunctival melanoma

AIM

Metastatic disease in ocular melanoma remains untreatable, is associated with late detection and is resistant to conventional systemic therapies. Many tumours including cutaneous melanoma express specific cancer-testis (CT) antigens and vaccines targeting these antigens can induce T-cell-mediated and humoural immune responses. The authors examined primary uveal and conjunctival melanomas for expression of CT antigens to assess their potential as targets for ocular melanoma immunotherapy.

METHODS

Paraffin-embedded uveal (n=32) and conjunctival (n=15) melanomas were assessed by immunohistochemistry for melanocyte differentiation antigens (gp100, Melan-A/MART-1 and tyrosinase), and CT antigens (MAGE-A1, MAGE-A3/6, MAGE-A4, MAGE-C1 and NY-ESO-1).

RESULTS

Melanoma differentiation antigens, gp100, Melan-A/MART1 and tyrosinase, were expressed in >75% of tumour cells in all uveal and conjunctival melanomas tested. Expression of all five CT antigens tested was low in uveal melanomas, and when present, stained <25% of the tumour cells. MAGE-A1, MAGE-A4 and NY-ESO-1 were expressed in <10% of tumour cells in conjunctival melanomas, while MAGE-C1 and MAGE-A3/6 were expressed in ∼20% and ∼35% of tumour cells in this malignancy, respectively, with variable expression levels.

CONCLUSIONS

Uveal and conjunctival melanomas consistently expressed high levels of the differentiation antigens (gp100, Melan-A/MART1 and tyrosinase). However, compared with other tumours, including cutaneous melanoma, only low levels of CT antigens were found in ocular melanomas. These observations suggest that immunotherapy directly targeting the CT antigens studied may not be effective for ocular melanoma.

The role of a multidisciplinary pre-assessment clinic in reducing mortality after complex orthopaedic surgery

INTRODUCTION

This paper describes an audit loop. The aim of this study was to audit the effect of a specialised preoperative anaesthetic assessment clinic after hip and knee arthroplasty and revision arthroplasty.

PATIENTS AND METHODS

We studied patients undergoing hip and knee surgery (arthroplasty and revision arthroplasty). We collected data concerning postoperative admissions to the high dependency unit (HDU), intensive care unit (ICU) and post-anaesthesia care unit (PACU) (planned and unplanned rates of admission, length of stay). We also noted mortality. In the first part of the study (April 2005 to March 2006) we studied 298 patients. All patients were assessed independently by an anaesthetist on the day of surgery. A multidisciplinary preoperative assessment clinic commenced in April 2006. After this date all patients were assessed preoperatively by a multidisciplinary anaesthetic lead team. In the second part of the study (May 2006 to April 2009) a further 1,147 arthroplasty patients were studied. Data were again collected regarding HDU, ICU, PACU and mortality, as noted above.

RESULTS

We found statistically significant (p = 0.001) reductions in the admissions to PACU (22% down to 10%) and in mortality (6.1% down to 1.2%) after the introduction of the pre-assessment clinic. There was also a statistically significant (p = 0.01) reduction in the HDU length of stay (2.1 days to 1.6 days), ICU unplanned admissions (1.3% to 0.4%) and the ICU length of stay (2.3 to 1.9 days). We estimated cost savings of nearly £50,000 in the second part of the study. This is based on the average decrease in HDU and ICU length of stay.

CONCLUSIONS

We recommend the use of a multidisciplinary pre-assessment clinic for complex orthopaedic surgery.

Conservative resection and adjuvant plaque brachytherapy for early-stage conjunctival melanoma

BACKGROUND

To describe the outcome of patients treated by conservative surgical excision followed by adjuvant plaque brachytherapy for early-stage primary or recurrent conjunctival melanoma.

DESIGN

Retrospective, non-comparative, interventional case series.

PARTICIPANTS

We reviewed 19 eyes in 19 consecutive patients presenting with biopsy proven conjunctival melanoma with pathologic stage pT1c or less.

METHODS

Patients with primary or recurrent early-stage conjunctival melanoma were identified and treated using a conservative resection technique (tractional micro-dissection) involving avoidance of deep dissection and modest lateral clearance followed by adjuvant plaque brachytherapy.

MAIN OUTCOME MEASURE

Local recurrence and ocular complications.

RESULTS

Mean age was 55.2 years and male : female (8:11). Mean follow up was 43.1 months (range 30.1-54.3 months). All patients were treated by conservative resection followed by adjuvant Iodine-125 plaque brachytherapy. The treatment dose was 100 Gy to a depth of 1.5-3.0 mm.

OUTCOMES

median visual acuity and intraocular pressure were unchanged after surgery. Six patients experienced corneal ulceration in the immediate postoperative period. No patients experienced recurrence at the treatment site or metastases. Three patients experienced new lesions distant from the treatment site.

CONCLUSIONS

Conservative resection and adjuvant plaque brachytherapy is an effective and well-tolerated modality for the management of patients with early-stage conjunctival melanoma.

Plaque brachytherapy for the management of ocular surface malignancies with corneoscleral invasion

PURPOSE

To describe the outcome of patients treated by surgical excision followed by plaque brachytherapy for primary or recurrent ocular surface malignancies with evidence of deep margin (corneoscleral) invasion.

METHODS

Retrospective, non-comparative, interventional case series. Eleven consecutive patients presenting with biopsy-proven scleral and/or corneal stromal involvement from either conjunctival melanoma (CM) or squamous cell carcinoma (SCC) of the conjunctiva were reviewed.

RESULTS

Five patients had CM (pT3 N0 M0 [n = 3], pT4 N0 M0 [n = 2]) and six patients had SCC (T3 N0 M0 [n = 6]). Mean age was 60.8 years and male:female (3:8). Mean follow up was 23.4 months (range 12-36 months). All patients were treated with Iodine-125 plaque following biopsy-proven corneoscleral invasion on histopathology. The treatment dose was 100 Gy to a depth of 1.5-2.5 mm.

OUTCOMES

Median visual acuity and intraocular pressure were unchanged after surgery. Five patients experienced corneal ulceration in the immediate postoperative period. None experienced recurrence at the treatment site. One SCC patient and two CM patients experienced new lesions distant from the treatment site. No sight-threatening complications were observed. No patients developed distant metastases.

CONCLUSION

Plaque brachytherapy is an effective and well-tolerated modality for the management of patients with ocular surface malignancy with evidence of localized corneoscleral invasion.

Australian Cancer Network clinical practice guidelines for the management of ocular and periocular melanoma: an evidence-based literature analysis

BACKGROUND

With recent advances in the diagnosis and management of ocular and periocular melanoma, many of which are based on results from randomized control trials, there is an increasing need for an evidence-based review of the literature for the Australasian population. The Australian Cancer Network has recently redeveloped the evidence-based Clinical Practice Guidelines for the Management of Melanoma, including a chapter on ocular melanoma. These are the first evidence-based guidelines on ocular melanoma to be created by the Australian Cancer Network.

METHODS

The primary research questions were formed and a detailed literature search was undertaken. Each relevant article was assessed and graded I-IV according to the level of evidence. Articles were grouped into bodies of evidence which were then assessed.

RESULTS

A total of 107 relevant articles were identified and grouped into 12 bodies of evidence. Guidelines based on this analysis were formulated and graded. These are presented below.

CONCLUSIONS

The management of ocular melanoma has benefited from recent advances in imaging, molecular biology and cytogenetics, and tumours today are detected earlier and with greater accuracy than 25 years ago. With improved treatment ocular and periocular melanomas can be controlled locally, with good preservation of vision in many patients. However, there remains no cure for metastatic disease.

Paediatric uveal melanoma

Uveal melanoma is extremely rare in the paediatric population and can be associated with various pre-existing conditions. We report the case of a 9-year-old girl with no predisposing factor who presented with choroidal melanoma. A review of the literature is presented and various clinical, histopathological and prognostic features of paediatric uveal melanoma are discussed.

Expression and distribution of MMPs and TIMPs in human uveal melanoma

Matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) are involved in tumour invasion, metastasis and angiogenesis, and have been implicated as progression markers in uveal melanoma, although their topographical expression has not been fully described. In this study we compared the distribution and specificity of several classes of MMPs (MMP-1, -2, -9, -19, and MT1-MMP) and physiological MMP inhibitors (TIMP-2 and -3) in different regions of the tumour microenvironment and adjacent choroid in a series of primary uveal melanomas. Paraffin sections of untreated uveal melanomas (n=18, 3/18 spindle; 11/18 mixed, and 4/18 epithelioid) were examined for MMP-1 (collagenase 1), MMP-2 and MMP-9 (gelatinases A and B), MT1-MMP (membrane-type 1-MMP), MMP-19, TIMP-2 and TIMP-3 (tissue inhibitors of MMPs), using indirect peroxidase immunohistochemistry. The distribution and intensity of immunolabelling was graded semi-quantitatively (0-3) by 2 independent observers. Non-parametric analyses were used to test for associations between tumour cell type, and the average grade of MMP or TIMP expression. Immunostaining for MMP-1, -9, -19 and MT1-MMP was > or =Grade 2 in more than 70% of specimens, and a heterogeneous pattern of MMP-1, -9, MT1-MMP and TIMP-3 expression was observed. At the tumour-scleral interface (TSI), melanoma cells had a flattened morphology and a much reduced MMP and TIMP expression, with a high expression in tumour areas adjacent to the TSI. Tumour vasculature and stromal cells strongly expressed MMP-2. We also observed heterogeneous immunostaining of the vasculature by MMP-1, -9, MT1-MMP and TIMP-2 antibodies, and of the extravascular matrix by MMP-9 antibody. The distinct immunostaining patterns observed for MMPs and TIMPs within uveal melanoma are consistent with their involvement in tumour growth and angiogenesis. In particular, the heterogeneous expression within regions of the tumours, and the localized expression in vasculature and stromal cells emphasises the importance of the tumour microenvironment in the pathogenesis of uveal melanoma (and other tumours).

Expression and distribution of MUC18 in human uveal melanoma

The immunoglobulin superfamily protein MUC18 is involved in transendothelial migration and signal transduction, and is expressed in malignancies including cutaneous melanoma. Recent in vitro studies showed evidence of increased MUC18 protein in some uveal melanoma cell lines with an increased potential for invasion. We assessed seven uveal and three metastasis-derived melanoma cell lines for the expression of MUC18 mRNA and protein by RT-PCR, and immunoblotting and immunocytochemistry, respectively. We also examined the expression and distribution of MUC18 in paraffin sections of primary uveal melanomas (n = 23; 5/23 spindle; 18/23 mixed and epithelioid) and normal eyes (n = 3) using a polyclonal goat anti-human antibody to MUC18 visualized with peroxidase and Vector NovaRED. Distribution and intensity of immunostaining was graded semi-quantitatively (grade 0 to 3) by 2 independent observers. All cell lines expressed MUC18 mRNA and protein ( approximately 130 kDa), and showed punctate cell membrane MUC18 immunostaining. Primary melanomas displayed heterogeneous cell membrane and cytoplasmic MUC18, with moderate to strong immunolabelling (> or =grade 2) in approximately 70% of tumours. Vasculature in tumours and in retina and choroid of all melanoma-affected and normal eyes showed intense MUC18 immunostaining. These observations further suggest a role for MUC18 in uveal melanoma growth; moreover, interactions between MUC18-positive melanoma cells and vasculature may be important for the hematogenous spread of cells during metastases.

Diffuse iris melanoma: Report of a case with review of the literature

Diffuse iris melanoma is an uncommon variant of anterior uveal melanoma. It is characterized by heterochromia and unilateral glaucoma secondary to angle invasion, and can be difficult to diagnose. We present a patient who had been managed for left-sided raised intraocular pressure with latanoprost eye drops for 12-months and pigmentary changes were subsequently noted. On referral to the Ocular Oncology Unit, Sydney, iris melanoma was suspected and confirmed on iridectomy, and the eye was eventually enucleated.

Management of metastatic carcinoma of the uveal tract: an evidence-based analysis

Uveal metastasis from carcinoma is the most common cause of ocular malignancy in adults and represents an increasing problem in the context of an ageing population and enhanced survival of stage IV cancer patients. The reported prevalence of clinically evident uveal metastases in carcinoma patients ranges from 2% to 9%, with breast and lung cancer together accounting for between 71% and 92% of cases. Most patients (66-97%) have a known history of cancer and, although the majority have metastatic lesions elsewhere, up to 33% may present with an isolated ocular metastasis. These lesions may progress rapidly and are potentially sight-threatening. Early diagnosis and appropriate timely treatment are therefore of paramount importance to maintain patients' quality of life. The diagnosis is usually clinical and detailed descriptions of symptomatology and physical characteristics are provided. In 21-50% of patients, involvement is bilateral. External beam radiotherapy (EBRT), chemotherapy, hormone and biological therapies, brachytherapy, transpupillary thermotherapy, laser photocoagulation/photodynamic therapy and enucleation are therapeutic modalities described in the literature for the management of uveal metastases. The strongest evidence favours timely EBRT for the management of sight-threatening uveal metastases. The published evidence supporting EBRT for sight-threatening uveal metastases was given a grade B (strong support for recommendation). Newer alternative therapies are emerging and may have a role in selected patients; however, there are unfortunately few large studies examining such treatments for carcinoma metastatic to the eye. The role of these modalities will be further clarified with the results of larger comparative trials.

Beta-lapachone inhibits proliferation and induces apoptosis in retinoblastoma cell lines

AIMS

To investigate the cytotoxicity of beta-lapachone, a potent agent that may selectively target tumour cells, in retinoblastoma (RB) cell lines.

METHODS

Growth inhibitory effects of beta-lapachone were evaluated in Y79, WERI-RB1, and RBM human retinoblastoma cell lines. Pro-apoptotic effects of beta-lapachone were evaluated in Y79 cells by detection of caspase 3/7 activity, by enzyme-linked immunosorbent assay for nucleosome fragments, and by cellular morphological analysis.

RESULTS

Beta-lapachone induced significant dose-dependent growth inhibitory effects in all three retinoblastoma cell lines. The 50% growth inhibitory concentration (IC(50)) of this agent was 1.9 microM in Y79 cells, 1.3 microM in WERI-RB1 cells, and 0.9 microM in RBM cells. Beta-lapachone also induced proapoptotic effects in RB cells. Treatment of Y79 cells with 1.9 microM beta-lapachone (IC(50)) resulted in a peak, fourfold induction of caspase 3/7 activity at 72 h post-treatment; a peak, 5.6-fold increase in nucleosome fragments at 96 h post-treatment; and a peak, 1.7-fold increase in the frequency of apoptotic cells at 48 h post-treatment, relative to vehicle-treated controls.

CONCLUSION

Beta-lapachone induced potent cytotoxic effects in RB cell lines at low micromolar concentrations, suggesting this agent could be useful in the clinical management of RB.

Porous Orbital Implants in Enucleation: A Systematic Review

Orbital implants have been used for cosmesis following surgical removal of the eyeball, or enucleation, for over a century. Implant design has progressed significantly in recent years with the use of porous devices, with the theoretical advantages of reduced complications and improved cosmesis. However, in some cases the theoretical benefits have not fully translated into clinical results. In this article the use of orbital implants in enucleation, with a particular focus on the newer porous biomaterials that have gained prominence over the last 15 years, is reviewed. Specific factors identified as affecting the performance of porous orbital implants include the material used, pore size, and morphology. Mechanical factors have received little consideration in the past and may form a basis for the use of higher compliance porous materials in the future. Of the porous materials in use, current clinical evidence is not sufficient to suggest either that porous implants are superior to non-porous implants, or that one material is more suited to the application than another. Future developments in this field require randomized controlled clinical trials with extensive follow-up as complications may not become evident until over 5 years post-implantation.

Role of topical chemotherapy for primary acquired melanosis and malignant melanoma of the conjunctiva and cornea: review of the evidence and recommendations for treatment

Surgical excision with cryotherapy is a well-established treatment option for malignant melanoma or primary acquired melanosis (PAM) with atypia of the conjunctiva and cornea. Topical chemotherapeutic agents such as mitomycin C (MMC) however, are increasingly finding use in clinical practice. A search was performed of Medline and Pubmed databases for English language articles from 1980 to the present in this field. Relevant studies were reviewed with regards to treatment regimen, rates of recurrence and metastasis, side effect profile and length of follow up. A total of 22 and 16 unique cases of biopsy proven PAM with atypia and malignant melanoma, respectively, treated with topical MMC were identified. Topical MMC was well tolerated and shows considerable promise, particularly in the treatment of diffuse PAM with atypia. However, long-term data are lacking and further studies are required.

Estimates of Ocular and Visual Retention Following Treatment of Extra-Large Uveal Melanomas by Proton Beam Radiotherapy

OBJECTIVE

To assess outcomes of proton beam radiotherapy for the treatment of extra-large uveal melanomas in patients specifically referred to the University of California, San Francisco, for ocular conservation therapy. Series patients uniformly refused enucleation both at an outside institution and again as a treatment option after extensive discussion at the University of California, San Francisco.

DESIGN

In a retrospective, nonrandomized cohort study, 21 patients with extra-large choroidal or ciliochoroidal melanomas measuring at least 10 mm in maximum thickness or 20 mm in maximum basal diameter or tumors located within 3 mm of the optic nerve measuring at least 8 mm in maximum thickness or 16 mm in maximum basal diameter met inclusion criteria. Main outcome measures were frequency of (1) anterior segment complications (lash loss, keratopathy, cataract, and neovascular glaucoma), (2) posterior segment complications (vitreous hemorrhage, radiation retinopathy, and radiation papillopathy), (3) treatment failure (tumor growth, enucleation, or metastases), and (4) final visual acuity.

RESULTS

Median follow-up was 28 months. Mean age at treatment was 58.3 years. The frequencies of hypertension and diabetes mellitus were 14.3% and 9.5%, respectively. Mean tumor thickness and mean basal diameter were 8.6 mm and 18.7 mm, respectively. Lash loss occurred in 52.4%; dry eye, in 23.8%; cataract, in 28.6%; neovascular glaucoma, in 38.1% (100% in patients with diabetes mellitus); radiation retinopathy, in 9.5%; and radiation papillopathy, in 9.5%. No patient developed radiation-associated scleral necrosis or vitreous hemorrhage. The 2-year Kaplan-Meier estimate of local tumor growth after treatment was 33%, and the rate of distant metastasis was 10%. Visual acuity of 20/200 or better was preserved in 25% of patients, including 4 patients (19%) who experienced an average of 4 lines of Snellen visual acuity improvement. Development of neovascular glaucoma was associated with tumors in close proximity to the optic nerve (P = .04), while cataract (P = .03) and lash loss (P = .02) occurred with more anteriorly located tumors. Proton beam radiotherapy provided a 67% probability of local control and 90% probability of clinically discernible metastases-free survival at 24 months after treatment.

CONCLUSION

Proton beam radiotherapy is an ocular-conserving option that may be considered for the treatment of extra-large uveal melanoma in carefully selected patients.

Ultrasound biomicroscopy: role in diagnosis and management in 130 consecutive patients evaluated for anterior segment tumours

BACKGROUND/AIM

Ultrasound biomicroscopy (UBM) is an important tool for assessing anterior segment pathology. This study sought to evaluate UBM in the management of anterior segment tumours.

METHODS

Retrospective analysis of medical records of consecutive patients referred to the ocular oncology unit, University of California San Francisco (UCSF), for suspected anterior segment tumours from 1999 to 2004.

RESULTS

132 eyes from 130 patients were evaluated, including 55 uveal melanomas (UM), 21 iris naevi, 30 iris cysts, and 26 remaining lesions. Of the melanomas, 45 were also evaluated with conventional A/B-scan. There was 29% correspondence between the anatomical structures invaded by melanoma as identified by B-scan v disease extent defined by UBM. Ciliary body and peripheral iris involvement by melanomas was significantly more frequently observed by UBM than B-scan. Seven of 30 benign cysts were diagnosed as cystic before UBM evaluation. In three cases, neuroepithelial cysts were associated with intercurrent pathology including iris naevus (n = 2) and ciliary body melanoma (n = 1). Two ciliary body melanomas showed cavitation, including one patient with a pseudocyst. Histopathological correlation was possible in six cases.

CONCLUSION

UBM is an indispensable tool for the management of anterior segment tumours. This study demonstrates the superiority of UBM v conventional B-scan for the precise localisation of uveal melanoma, especially involving the ciliary body and peripheral iris.

Retinoblastoma: Animal Models

Employment of animal models in basic research has significantly advanced the understanding of fundamental processes underlying tumorigenesis in retinoblastoma, including elucidating the complex role of pRb and other related protein products in cell cycle regulation, apoptosis, DNA damage responses, and terminal differentiation. The evolution of therapy for retinoblastoma has also been facilitated through translational research using in vivo models, including xenograft and genetically engineered systems. In retinoblastoma, these models provide a valuable preclinical context for testing the efficacy and safety of conventional chemotherapy, radiotherapy, or novel agents on tumor growth, tissue invasion, and metastasis.

Isolated neurofibroma of the orbit with extensive myxoid changes: a clinicopathologic study including MRI and electron microscopic findings

Isolated orbital neurofibroma (INO) without systemic neurofibromatosis is rare. Previous reports including MRI with elaboration of the ultrastructural features of the cellular and extracellular components in INO do not exist. A 44-year-old male presented with painless, slowly progressive proptosis (6 mm) and downward displacement (3 mm) of the left eye of two years duration. MRI revealed a suprabulbar mass hypointense to fat, isointense to brain on T1-weighted images with small hyperintense areas following contrast enhancement. T2-weighted images showed a predominantly hyperintense mass with a few hypointense islands. The lesion was excised using an anterior superior transseptal orbitotomy. Histopathologically, large areas of a paucicellular myxoid stroma containing mucopolysaccharides made up approximately three-quarters of the mass. Focal hypercellular areas showed marked collagen deposition. Blood vessels were distributed at the periphery of the lesion and in association with nodules of nerve sheath cells. Ultrastructurally, perineural and fibroblast-like cells were loosely arranged in a myxoid stroma. Schwann cells were embedded in a dense collagenous matrix. Variable differentiation of Schwann cells, perineural cells and fibroblast-like cells associated with a more solid (collagenous) or loose (myxoid) extracellular matrix may determine the characteristic, though not specific, MRI features in isolated neurofibromas of the orbit.

Frequency and clinical features of visceral malignancy in a consecutive case series of patients with periocular sebaceous gland carcinoma

PURPOSE

To report the frequency and clinical features of internal visceral malignancy in an unselected series of patients with sebaceous gland carcinoma (SGC).

METHODS

A non-comparative retrospective case series of consecutive patients with a histologically proven diagnosis of periocular sebaceous cell carcinoma treated at the University Eye Hospital, University of Erlangen-Nürnberg between 1981 and 2000.

RESULTS

Twenty-three patients were identified, each with one tumor. Men and women were almost equally affected with a mean age at diagnosis of 62 years (range 37-83 years). The majority of tumors were located in the upper lid, but five tumors were situated in the lower lid or caruncle. In 22 of the 23 patients the diagnosis at referral was either incorrect or not suspected. In all cases, the SGC was treated by surgical excision. In the systems review, 11 of the 23 patients (48%) had evidence of previous systemic malignancy, the most common being colorectal cancer followed by liver and bronchial carcinoma. Forty-five percent of patients with SGC and internal visceral malignancy eventually died as a result of their tumors.

CONCLUSION

Periocular SGC remains an underdiagnosed entity for which a high level of clinical suspicion is critical for early recognition. Almost half the patients additionally had an internal visceral malignancy. Internal visceral malignancy in unselected patients with SGC may be more common and have a more guarded prognosis than has been appreciated.

Pseudoexfoliation syndrome: pathological manifestations of relevance to intraocular surgery

Pseudoexfoliation syndrome (PEX) is a common ocular condition often associated with the need for intraocular surgery. Although results of cataract and glaucoma filtering surgery in eyes with PEX in the early stages of the disease may be comparable to those in eyes without PEX, in the later stages morbidity is significantly increased due to periocular surgical complications and the outcome is worse. Surgical and postoperative difficulties are often multifactorial and are directly related to the pathological changes of PEX on intraocular structures. Recent years have seen a large increase in the understanding of the effects of PEX on the various ocular tissues. Although the visible areas of the anterior capsule are most obviously involved, this is only a small part of the picture and of least significance. Biomicroscopically invisible changes of the zonules and their attachments are of greatest consequence. There is also distinct, often active, involvement of almost all tissues of the anterior segment of the eye, many of which have important implications for the anterior segment surgeon including iridopathy, iris vasculopathy (including persistent breakdown of the blood-aqueous barrier and anterior segment hypoxia), ciliary body involvement and keratopathy. Trabecular dysfunction is evident by the deposition of PEX material derived from both in situ and extra-trabecular production as well as protein and melanin deposition. These changes should be kept in mind by all intraocular surgeons as a source of potential difficulties in the perioperative period. Additionally, in light of these changes, patients need to be given realistic expectations regarding the increased risk of complications and more prolonged expected recovery time. In this short review, current reports relating to PEX pathological changes of practical interest to the intraocular surgeon are summarized.

Surgery for primary basal cell carcinoma including the eyelid margins with intraoperative frozen section control: comparative interventional study with a minimum clinical follow up of 5 years

AIM

To assess recurrence of primary basal cell carcinoma (PBCC) including the eyelid margins after resection with or without intraoperative frozen section control (IFS).

METHODS

Comparative non-randomised interventional study involving review of records of consecutive patients with histological diagnosis of PBCC including the eyelid margins, treated surgically at the University of Erlangen-Nürnberg between 1989 and 1998. Patients with a minimum clinical follow up of 5 years treated with (group I) or without (group II) IFS were compared. Postoperatively, permanent paraffin sections were available in all patients.

RESULTS

165 patients were available for study. There were 145 patients with a minimum of 5 years follow up. Of these, no tumour recurrences were observed in group I (n = 114) compared with three (9.7%) in group II (n = 31) (p = 0.002).

CONCLUSIONS

Surgery for PBCC including the eyelid margins with IFS and immediate plastic reconstruction, as performed in the present study, is associated with better long term cure compared with surgery with clinical control.

Therapie maligner Melanome der Konjunktiva bei prim�r erworbener Melanose (PEM) mit Mitomycin-C-0,02%-Augentropfen

BACKGROUND

The therapy of malignant diseases of the conjunctiva with local chemotherapy is an extension of the therapeutic options in this field. We report on our experience in the therapy of malignant melanomas of the conjunctiva associated with primary acquired melanosis (PAM).

METHODS AND PATIENTS

Between March 1998 and April 2001, 13 patients with malignant melanoma of the conjunctiva associated with PAM (6 female; 7 male; mean age 57+/-13 years) were treated with local chemotherapy. The tumor was classified as stage pT2 (pN0, pM0) in seven patients, stage pT3 (pN0, pM0) in three patients and in the remaining three patients the lid was involved in the malignant process (pT4, pN0, pM0). Local chemotherapy (mitomycin C 0.02% eyedrops 5 times a day) was applied after incisional biopsies in 2 cycles for 14 days with a 14-day break. In 4 patients a third cycle was included.

RESULTS

Regression of the tumor was observed after completion of the therapy in all cases. Severe ocular or systemic secondary effects were not seen in our patients. Nine patients were without recurrence within the follow-up time. In three patients, a recurrence of the disease was observed. In these cases, the eyelid was involved in the process.

CONCLUSION

Local chemotherapy with mitomycin C is a useful option in the treatment of malignant melanomas of the conjunctiva associated with PAM if the tumor stage is pT3 or less. From our point of view the combination with incisional biopsy is of great benefit. Prognosis of conjunctival malignant melanomas involving the lid margin (pT4) is poor.

Human uveal melanoma expresses NG2 immunoreactivity

BACKGROUND/AIMS

NG2 is the rat homologue of the human melanoma proteoglycan (HMP), also known as the high molecular weight melanoma associated antigen. Most cutaneous melanomas, as well as glioblastomas, chondrosarcomas, and some leukaemias express NG2 immunoreactivity, recognised using monoclonal antibody (mAb) 9.2.27. This antibody has also been used for molecular targeting in targeted alpha therapy for melanoma. The purpose of this study was to evaluate the expression of NG2 immunoreactivity in human uveal melanoma and normal ocular tissue using mAb 9.2.27.

METHODS

Enucleated eyes from 26 patients with choroidal or ciliary body melanoma (n=26) were available as paraffin sections, and stained with haematoxylin and eosin to assess for tumour cell type and histopathology. Additional slides were investigated for NG2 immunoreactivity using mAb 9.2.27 and alkaline phosphatase anti-alkaline phosphatase (APAAP) immunostaining. Two independent observers graded immunostaining using a semiquantitative scale from 0 (negative) to 3 (strong).

RESULTS

Immunostaining for mAb 9.2.27 could not be graded in 7/26 cases with dense pigmentation of the tumour. For the remaining cases, grade 2 (moderate) or more immunostaining was seen in 18/19 tumours (95%). The retina, retinal pigment epithelium (RPE), and choroid displayed weak immunostaining (grade 0.5-1.5) in the majority of melanoma affected eyes. Normal retina and choroid (n=5) appeared negative for mAb 9.2.27. Optic nerve axon bundles in both control and melanoma affected eyes displayed moderate immunostaining.

CONCLUSION

In the present study, the majority of human uveal melanomas expressed NG2 immunoreactivity, as detected using mAb 9.2.27. This antibody may be a suitable candidate for radioimmunotherapy to target ocular melanoma.

Biomolecular markers of malignancy in human uveal melanoma: the role of the cadherin-catenin complex and gene expression profiling

In recent years there has been a trend towards conservative management of uveal melanoma (UM), aimed at preserving the eye and vision. Despite improvements with this approach, recurrent tumour and metastatic disease still occur, and the management remains problematic. As a result of these limitations, there is interest in gaining a greater understanding of molecular changes associated with aggressive disease patterns in UM. This might result in new, more effective and less toxic therapies as well as provide prognostic information for defining subgroups of patients with a less favourable prognosis as potential candidates for adjuvant therapies. Accumulating evidence over the past decade suggests that disturbance in the cadherin-catenin adhesion complex is critical in the process leading to invasion and metastasis of many cancers. The recent advent of DNA micro-array technology now offers an unprecedented ability to study these molecules and others associated with malignant transformation. In this mini-review, the aspects of tumour progression in which cadherin-catenin may be involved are dealt with along with the potential application of DNA micro-array technology to the problem in UM.

Primary iris melanoma: diagnostic features and outcome of conservative surgical treatment

AIMS

To describe features influencing the management of primary iris melanoma and report the outcome of conservative surgical treatment of patients diagnosed with this condition in a tertiary referral academic setting over a 20 year period.

METHODS

Retrospective non-comparative case series of consecutive patients diagnosed with iris melanoma from 1980-2000 using medical records from the University of Sydney Department of Ophthalmology and NSW Cancer Registry

RESULTS

51 cases were identified. The most common presentation was growth of a previously noted pigmented lesion. Initial management was either observation or local resection (two had enucleations) with iris reconstruction where possible (23.8%). The mean follow up was 8.7 years (range 1-17 years). Vision of 6/12 or better was maintained in the majority (78.6%) treated by local resection. Pupil reconstruction significantly reduced reported postoperative glare symptoms. Four patients had features suggestive of local recurrence and there was no documented metastatic disease or death from iris melanoma in this series. Histologically, the majority were spindle B cell melanomas. Clinical features including prominent tumour vascularity, rapid growth, and heterogeneous pigmentation were each significantly associated with an epithelioid cell component. Involvement of the iridocorneal angle was frequently associated with ciliary body invasion.

CONCLUSIONS

Management decisions for iris melanoma will depend on the clinical features. Mixed or epithelioid histology is more likely in the presence of two or more of the features of malignancy and may justify earlier intervention. When treatment is undertaken, local resection achieves long term tumour clearance with an acceptable morbidity. In resecting iris melanoma, careful assessment for iridocorneal angle involvement is important in treatment planning. Iris reconstruction has a useful role in reducing postoperative photophobia.

Sodium butyrate modulates p53 and Bcl-2 expression in human retinoblastoma cell lines

Sodium butyrate (SB) is a potent biological modifier that can induce diverse effects including growth inhibition, differentiation, or apoptosis of many cell types including retinoblastoma (Rb), and modulation of genes such as c-fos and p53. In this study we assessed the effects of SB on cell growth and expression of p53, critical for cell cycle control, and Bcl-2, an inhibitor of apoptosis, in two human Rb cell lines (Y79 and WERI-Rb1). Attachment cultures were treated with 1 mM SB for up to 5 days and immunocytochemistry was used to examine for the expression of neural cell adhesion molecule (NCAM), p53, and Bcl-2. Suspension cultures of both cell lines were also treated with 1 and 4 mM SB, and at selected times cell extracts were prepared and the expression of p53 and Bcl-2 proteins determined by Western blot analysis. Treatment with 1 mM SB of both cell lines for 5 days inhibited growth and induced morphological changes including extension of neurite-like processes. Up to 12 h after 1 mM SB treatment, p53 and Bcl-2 expressions were similar to control levels, then gradually decreased to very low levels at 5 days. SB (4 mM) also inhibited growth associated with cell death, which was apparent at 24 h posttreatment. Expressions of p53 and Bcl-2 were decreased below control levels at 4 h, and by 24 h only very low levels of protein were detected. SB-induced modulation of p53 and Bcl-2 expression may have implications for controlling Rb growth, particularly in combination with chemotherapy drugs, which are increasingly used in the treatment of Rb.

The development of ISO 9002 quality management standards for Canadian dental practices

The department of dentistry of the Hospital for Sick Children has actively maintained a quality assurance system since the early 1980s. In addition, members of the department have taught courses and published articles on risk management and quality assurance for over a decade. The decision to achieve ISO 9002 registration led to an intensive 10-month process to adapt ISO systems and standards to Canadian institutional dental practice. This article describes the ISO registration system and the changes required for an existing quality assurance program to conform to ISO standards.

Vincristine- and cisplatin-induced apoptosis in human retinoblastoma. Potentiation by sodium butyrate

Chemotherapy alone has largely been unsuccessful in controlling retinoblastoma growth, and has traditionally been limited in use as an alternative to irradiation for the treatment of retinoblastoma. Recently, clinical studies combining chemotherapy with local therapies, including radiotherapy, laser therapy or cryotherapy and in some cases, cyclosporine A, have been effective in treating retinoblastoma. Differentiating agents may also be combined with chemotherapy to enhance the action of cytotoxic drugs on tumor cell growth, although this approach has not been fully investigated in retinoblastoma. In this study, we evaluated the cytotoxic response of human retinoblastoma cell lines (Y79 and WERI-Rb1) to two chemotherapy agents commonly used in treating retinoblastoma, vincristine (VCR) and cisplatin (CDDP). Retinoblastoma cells have been shown to be sensitive to the differentiating agent sodium butyrate, and cell lines were also treated with a combination of VCR or CDDP with sodium butyrate, and the effects on retinoblastoma viability assessed. Both VCR and CDDP induced dose-dependent death of Y79 and WERI-Rb1 cells, accompanied by nuclear and cytoplasmic condensation and DNA laddering, features characteristic of apoptosis. Inhibitors of macromolecular synthesis, cycloheximide and actinomycin-D, significantly reduced VCR- and CDDP-induced apoptosis, although putative endonuclease inhibitors zinc sulphate and aurintricarboxylic acid had no apparent effect. Treatment with 0.5 mM or 1 mM sodium butyrate combined with VCR or CDDP significantly increased induction of apoptosis by these agents. This augmentation of chemotherapy-induced apoptosis may have implications for retinoblastoma therapy.

Human retinoblastoma: in vitro differentiation and immunoglobulin superfamily antigen modulation by retinoic acid

Suspension and attachment cultures of Y79 human retinoblastoma cells were treated with all-trans retinoic acid (RA) for up to 10 days to assess its effect on growth and cell-surface expression of immunoglobulin superfamily antigens MHC class I and class II, ICAM-1, NCAM and Thy1. RA up to 10 microM induced growth inhibition, and marked morphological differentiation with extension of prominent processes resembling neurites was seen in attachment cultures. However, above 10 microM RA produced extensive cell death. We also observed increased cell-surface expression of MHC class I, ICAM-1, NCAM and Thy1 on Y79 cells treated with 10 microM over 10 days; constitutive MHC class II expression was not apparent, nor did RA treatment appear to induce Y79 cells to express MHC class immunoreactivity. The up-modulation of cell-adhesion molecules (NCAM, ICAM-1 and Thy1) and immune recognition molecules (NCAM, ICAM-1 and MHC class I), associated with reduced growth and tumour cell differentiation, suggests that RA may have a potential role in regulating the growth and development of retinoblastoma tumours.