Predicting local control of choroidal melanomas following ¹⁰⁶Ru plaque brachytherapy

BACKGROUND

We evaluated the control rate of choroidal melanomas treated with ¹⁰⁶Ru plaque brachytherapy to identify the risk factors associated with local recurrence and lack of response.

METHODS

A retrospective review of ¹⁰⁶Ru plaque brachytherapy for patients with choroidal melanoma treated at St Bartholomew's Hospital, London. Survival analysis was used to assess associations between evaluated age, sex, location, foveal proximity, tumour base and height, presence of lipofuscin and subretinal fluid, apex dose, radiation rate and type of plaque with time to local recurrence. Logistic regression analysis was used to assess to evaluate the association between the same set of variables and lack of tumour response.

RESULTS

From January 2002 to December 2006 189 patients were treated. The follow-up ranged from 12 to 78 (median 33) months. None of the patients received adjuvant diode laser thermotherapy. The control rate was 85.7% (14 recurred while 13 did not respond). Of the patients who had local recurrence, univariate survival analysis demonstrated an association with younger patients, foveal proximity, preoperative subfoveal fluid and tumour base >11 mm. Age and foveal proximity remained significant in a Cox multiple variable model (p=0.03). Of the patients who did not respond, logistic regression analysis showed that lack of response was associated with a tumour height >5 mm, confirmed through multiple variable analysis (p=0.027).

CONCLUSIONS

Tumours that are close to the fovea in young patients appear more likely to show local recurrence. Tumour height >5 mm was the only prognostic factor that determined lack of response. These results may be used to select which tumours require adjuvant therapy.

Retinoblastoma in Great Britain 1963-2002

AIM

This paper describes the epidemiology and family history status of 1601 children with retinoblastoma in Great Britain diagnosed 1963-2002 and summarises the practical consequences for diagnosis and counselling of developments in molecular genetics.

METHODS

Incidence rates were analysed according to year of diagnosis and tumour laterality. Cases were classified as heritable or non-heritable on the basis of laterality and family history of the disease.

RESULTS

There were 998 unilateral cases, 581 bilateral and 22 of unknown laterality. Bilateral cases tended to be diagnosed at a younger age than unilateral. All bilateral cases are regarded as heritable, and 35% had a family history of the disease. 7% of the unilateral cases had a family history and are therefore heritable. Thus, at least (41%) of our cases are heritable. This is an underestimate, since these data on family history are incomplete. For unilateral cases aged below 1 year, the reported incidence rate increased significantly (p<0.0001) by about 2.5% per year; for the age group 1-4 years, the average increase was about 0.5% per year (not significant).

Vitreous relapse following primary chemotherapy for retinoblastoma: is adjuvant diode laser a risk factor?

AIMS

To evaluate rates of vitreous relapse among retinoblastoma patients treated with primary chemotherapy and assess diode laser as a potential risk factor for relapse.

METHODS

Retrospective review of all patients treated with primary chemotherapy at a large ocular oncology centre. Eyes that developed vitreous relapse were coded with regard to Reese-Ellsworth Group, laterality, time to relapse, type of relapse (vitreous base or non-vitreous base relapse), treatments used (including adjuvant diode laser), and ocular preservation. Individual tumour foci treated with laser hyperthermia were also coded for laser parameters including power settings, number of treatments, and concomitant administration of systemic chemotherapy (chemothermotherapy).

RESULTS

15 of 106 eyes (14.15%) developed vitreous relapse over a 6 year period. Mean time to relapse was 7.2 months after chemotherapy was completed. Five cases (33%) were of the vitreous base variety. Ocular salvage was attempted in 11 cases using a variety of methods; one patient was lost to follow up. Six of the remaining 10 eyes (60%) were salvaged. Eight of 38 eyes (21%) treated with systemic chemotherapy and laser hyperthermia developed vitreous relapse compared with seven of 68 eyes (10%) treated with primary chemotherapy alone (p<0.005). Laser settings, number of hyperthermia treatments, and the concomitant use of systemic chemotherapy (chemothermotherapy) were not associated with higher rates of vitreous relapse.

CONCLUSION

Nearly one in seven eyes with retinoblastoma treated with primary chemotherapy may develop vitreous relapse. The administration of diode laser hyperthermia appears to increase this risk. Despite additional therapy a number of these eyes succumb to enucleation.

Proton beam therapy and iris neovascularisation in uveal melanoma

PURPOSE

Local treatment of uveal melanoma by radiotherapy involves the use of brachytherapy with radioactive plaques attached to the sclera, or proton irradiation. Both treatments induce growth arrest within the tumour and its slow involution over several years. Although ocular retention rates are excellent, regrowth of tumours due to resistance and neovascular glaucoma leads to enucleation of up to 10% of affected eyes. Proton irradiation involves part of the iris in most cases and we noticed that neovascularisation only occurred in the part of the iris that was not irradiated. We therefore conducted this study to determine the relationship between the development of iris neovascularisation and iris irradiation.

METHODS

A total of 21 enucleation specimens from patients who had previously had proton irradiation were collected from the files of the Department of Pathology, Moorfields Eye Hospital during the 5-year period from 1994 to 1999. Sections of these eyes were assessed for VEGF-A, bFGF, and von Willebrand Factor (vWF) by immunohistochemistry. Ophthalmic notes and radiotherapy records were reviewed to assess the extent of iris irradiation.

RESULTS

In all, 11 cases showed clinical evidence of iris neovascularisation and were selected for further study. Three of these eyes also showed clinical evidence of regrowth of the tumour. Histological evidence of iris neovascularization was noted in all 11 of the eyes examined, and was only present in the nonirradiated side of the iris in 8/11 eyes. NVI was present on both sides of the iris in three cases, but was less severe in the irradiated part. Expression of VEGF-A was at most weak within the tumour, but was present in the detached retina and in the epithelium of both ciliary body and iris. Some bFGF staining was noted around vessels in the iris stroma.

CONCLUSIONS

Our results suggest that irradiation leads to iris atrophy, and that atrophic, irradiated iris is resistant to the development of neovascularisation.

Recruiting donors for autopsy based cancer research

The use of human tissue for scientific research is a highly sensitive issue. A lack of confidence in patient recruitment is one reason for the failure of many studies to be funded and it is important therefore that recruitment procedures are as effective and sympathetic as possible. The authors recruited patients with uveal melanoma into a postmortem study investigating tumour latency in this cancer. Two approaches were used--firstly a direct approach when patients attended clinic and secondly an initial approach by mail followed by telephone contact. In the first year of study the authors had a take up rate of 88.5%, significantly higher than the average rate of 40% quoted by the National Institute for Clinical Excellence (NICE). Key features are a sympathetic personal approach by experienced oncology nurses, the provision of clear information, and the inclusion of the next of kin in the recruitment procedure.

Globe conserving treatment of the only eye in bilateral retinoblastoma

AIMS

To quantify the rates of eye preservation and patient survival, local tumour relapse and recurrence, and development of new tumours in the remaining eye of children with bilateral retinoblastoma with one eye already enucleated. Also, in the same children, to describe the types of primary and secondary treatment procedures, and to define the anatomical outcome.

METHODS

This is a retrospective observational case series report. The study participants consisted of 107 patients with bilateral retinoblastoma with one eye enucleated within 1 month of baseline examination and had their remaining eye treated conservatively. The main outcome measure were: primary treatment failures, new tumours, enucleation of the only eye, death, remission, and anatomical outcomes (retinal detachment, vitreous haemorrhage, and cataract).

RESULTS

The median age at diagnosis was 8.4 (range 0.2-44, SD 10.1) months with a median ophthalmic follow up of 44.3 (8.1-114, SD 10.1) months. In 22 of the 107 patients (21%) the treated eye was in Reese Ellsworth groups I or II and in the remaining 85 (79%) in groups III-V at diagnosis. The primary treatment was cryotherapy in 14% (15/107) of eyes, radioactive plaque brachytherapy in 3.7% (4/107), and chemotherapy in 10% (11/107). It was lens sparing radiotherapy in 37% (40/107), whole eye radiotherapy in 29% (31/107), combined radiotherapy and chemotherapy in 2.8% (3/107), chemothermotherapy in 0.9% (1/107), and combined focal therapy in 1.8% (2/107). The primary treatment failed to achieve local tumour control during the follow up period in 37% (40/107) of eyes. In 17 eyes failure was due to inadequate control of the presenting tumour, in 16 to development of a new tumour, and in eight eyes to a combination of both. 35 (88%) of the 40 failures were managed by secondary conservative treatment and the remaining five were treated by enucleation of the only eye. There were eight (7.4%) deaths and the 3 year survival rate was 93% (100/108). Anatomical results included vitreous haemorrhage in four cases, tractional retinal detachment also in four cases, and 24 children required cataract surgery.

CONCLUSIONS

Aggressive conservative treatment achieved a good rate of globe salvage without impairing survival.

Absence of BRAF gene mutations in uveal melanomas in contrast to cutaneous melanomas

The recent discovery of activating mutations in the BRAF gene in many cutaneous melanomas led us to screen the genomic sequence of BRAF exons 11 and 15 in a series of 48 intraocular (uveal) melanomas, together with control samples from three cutaneous melanomas and the SK-Mel-28 cell line, which has a BRAF mutation. The same mutation was detected in two-thirds of our cutaneous melanoma samples, but was not present in any uveal melanomas. This finding further underlines the distinction between uveal and cutaneous melanomas, and suggests that BRAF inhibitors are unlikely to benefit patients with uveal melanoma.

Uveal melanomas express vascular endothelial growth factor and basic fibroblast growth factor and support endothelial cell growth

BACKGROUND

Tumour microvascularity is a significant determinant of prognosis for a large number of different tumours, including uveal melanoma. The development of blood vessels within these and other tumours is partly controlled by soluble pro-angiogenic cytokines, of which basic fibroblast growth factor (bFGF) and vascular endothelial growth factor-A (VEGF) are the best described.

METHODS

Because VEGF has been inconsistently found within uveal melanomas and bFGF is described as an autocrine growth factor in cutaneous melanoma, the authors looked at the expression of these cytokines in uveal melanomas using immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR). The cross talk between uveal melanoma cells and endothelial cells was then assessed in an in vitro co-culture model.

RESULTS

While most tumour cells expressed bFGF at the protein level by immunohistochemistry (89%), relatively few (22%) expressed VEGF, and this was of limited extent. All 20 tumours tested by RT-PCR contained mRNA for both bFGF and VEGF. Co-culture experiments using an ATP based bioassay showed that uveal melanomas could support the growth of a rat brain endothelial cell line (GPNT) and human umbilical vein endothelial cells (HUVEC), and that this could be modulated by cytokines and anti-cytokine antibodies.

CONCLUSION

These results suggest that angiogenesis within uveal melanoma may be the result of a complex interplay between endothelial and tumour cells, and that bFGF and VEGF could play a part.

Vascular endothelial growth factor is elevated in ocular fluids of eyes harbouring uveal melanoma: identification of a potential therapeutic window

BACKGROUND

Improved local treatment of uveal melanoma makes it possible for many patients to retain the affected eye, but a proportion will develop secondary complications such as neovascularisation of the iris (NVI) and require enucleation. Although vascular endothelial growth factor A (VEGF-A) is known to correlate with NVI and can cause NVI in experimental models, this pro-angiogenic cytokine is consistently reported to be absent in uveal melanoma. Novel anti-VEGF therapies are now in clinical trial, and the authors therefore wished to determine whether VEGF-A was indeed elevated in melanoma bearing eyes.

METHODS

VEGF-A concentrations were measured in aqueous and vitreous from 19 and 30 enucleated eyes respectively.

RESULTS

Elevated VEGF-A concentrations (up to 21.6 ng/ml) were found in melanoma bearing eyes compared with samples from patients undergoing routine cataract extraction (all had values below 0.96 ng/ml). Immunohistochemistry showed VEGF-A protein in the iris and/or ciliary body of 54% and basic fibroblast growth factor (bFGF) in 82% of the eyes examined. VEGF was found to a limited extent and at very low levels in only 9% of these tumours. Aqueous or vitreous VEGF levels showed no apparent correlation with retinal detachment, tumour size, vascularity, or immunohistochemistry. Though limited in number, the highest VEGF levels correlated with previous radiation therapy, and with the presence neovascularisation of the iris or optic nerve head. bFGF was not significantly elevated in ocular fluids: it is known to be a pro-angiogenic agent and was detected in the majority of primary uveal melanomas.

CONCLUSION

Based on this study, though the source of VEGF within eyes harbouring uveal melanoma is not clear, these data suggest that anti-VEGF therapy might prove useful in the management of some patients with NVI secondary to uveal melanoma.

Primary orbital melanoma masquerading as vascular anomalies

PURPOSE

To review two cases of primary orbital melanoma presenting like orbital vascular anomalies.

METHODS

Retrospective review of clinical presentation, treatment, radiology and pathology for two patients under the care of the Orbital Clinic at Moorfields Eye Hospital.

RESULTS

Both lesions presented with the appearance and behaviour of vascular anomalies. In one case, a spindle cell melanoma appeared to be a low flow vascular anomaly with a loculated secondary haemorrhage and, in the other case, a melanoma of soft parts was considered to be an arteriovenous malformation and responded partially to embolisation.

CONCLUSION

Primary malignant melanoma may present as a secondary vascular lesion of the orbit and this very rare tumour should be considered in the differential diagnosis of any vascular anomaly.

Comparison of the ex vivo chemosensitivity of uveal and cutaneous melanoma

Cutaneous and uveal melanoma both have a poor prognosis and chemotherapy is usually unsuccessful. We have previously reported the activity of a number of cytotoxic agents against metastatic cutaneous and primary choroidal uveal melanoma using an ex vivo adenosine triphosphate (ATP)-based chemosensitivity assay (ATP-TCA). In this study we compare the results obtained with the two types of melanoma. Cutaneous melanoma deposits in skin and lymph nodes (n = 58) and choroidal melanomas (n = 77) were tested using the ATP-TCA. Analysis of the data based on an arbitrary threshold for sensitivity shows that both types of melanoma exhibit heterogeneity of sensitivity to all the agents and combinations tested. With all the single agents except gemcitabine, cutaneous melanomas showed greater sensitivity in the assay, though this did not achieve statistical significance. This was also true with the drug combinations, with the exception of treosulfan + gemcitabine, which had similar activity in each type of melanoma. Of all the single agents tested, doxorubicin (47% of specimens classed as sensitive), vinorelbine (43%), treosulfan (41%) and paclitaxel (33%) showed the greatest activity with cutaneous melanoma. In the uveal melanoma samples, mitoxantrone (33%), gemcitabine (22%) and treosulfan (21%) showed the greatest activity. In contrast to the cutaneous melanomas, 13% of the uveal melanomas were sensitive to paclitaxel, 4% were sensitive to doxorubicin and 11% were found to be sensitive to vinorelbine. Both tumour types showed greater sensitivity to combinations of cytotoxic agents. The combination of treosulfan + gemcitabine was universally effective, with 72% of cutaneous melanomas and 80% of uveal melanomas exhibiting activity at the level selected to indicate sensitivity in the assay, though this will not necessarily indicate a similar level of clinical sensitivity.

Differential immunoreactivity of melanocytic lesions of the conjunctiva

AIMS

To evaluate the expression of S100NKI/C3 and HMB45 antigens in melanocytic lesions of the conjunctiva and the ability of HMB45 to aid assessment of neoplasia.

METHODS AND RESULTS

Stored formalin-fixed specimens of conjunctival melanomas and primary acquired melanosis were considered as participants and conjunctival naevi and racial melanosis as controls. Ninety-seven conjunctival melanocytic lesions were analysed using formalin-fixed paraffin-embedded material. These included 20 melanomas arising in the context of primary acquired melanosis (PAM), 22 melanomas arising without evidence of pre-existing PAM, seven cases of PAM with atypia, nine cases of PAM with no atypia, 35 conjunctival naevi and four cases of racial melanosis. S100 and NKI/C3 were similarly expressed in all lesions, with at least one of these markers positive in 100% of the lesions examined. HMB45 was expressed in 72.7% of primary melanomas and 85% of melanomas in the context of PAM; 42.8% of PAM with atypia expressed HMB45 while it was expressed in 11.1% of PAM without atypia and 8.5% of naevi. Racial melanosis cases did not express HMB45. S100 and NKI/C3 were expressed to a similar extent in all groups.

CONCLUSIONS

S100 and NKI/C3 are useful markers to assess the extent of melanocytic lesions in the conjunctiva. HMB45 immunoreactivity can act as a useful aid to histopathology for the distinction of benign from malignant conjunctival lesions, particularly in the context of primary acquired melanosis.

Abnormalities of the transforming growth factor-beta pathway in ocular melanoma

The majority of ocular melanomas occur in the uveal tract. Chemotherapy is generally ineffective and large tumours requiring enucleation have a greater than 50% mortality at 5 years. Monosomy for chromosome 3 is common in uveal melanoma and it is known that there is loss of responsiveness to transforming growth factor beta (TGFbeta) in melanoma cell lines. Since the gene for TGFbeta receptor II (TGFbetaR2) is located on chromosome 3p22, this study investigates the possibility that the TGFbeta pathway, and TGFbetaR2 in particular, might be involved in the pathogenesis of this rare eye tumour. To this end, the expression of molecules in the pathway has been examined by immunocytochemistry (TGFbeta, TGFbetaR2, SMAD2, SMAD3, SMAD4, and p27), backed up by a cell culture assay of TGFbeta-mediated growth suppression, RT-PCR for SMAD4, and loss of heterozygosity (LOH) on 3p22. There was LOH at 3p22 in 6/19 tumours and loss of TGFbetaR2 expression in 10/27 tumours. Immunohistochemistry for SMADs 2, 3, and 4 showed potential loss of signal transduction in 14/27 tumours. The results indicate abnormality of the TGFbeta pathway in 61% of tumours for which unequivocal results were obtained and suggest that abrogation of control of melanocyte growth by the TGFbeta pathway may be important in the formation of uveal melanoma.

Relationship between expression of topoisomerase II isoforms and chemosensitivity in choroidal melanoma

Choroidal melanoma has a high mortality rate and responds poorly to existing chemotherapy, but unexpected ex vivo sensitivity of a subset of these tumours to topoisomerase II inhibitors has been noted. Since chemoresistance may be mediated by the molecular phenotype of tumours, immunohistochemistry has been used to study the expression of both isoforms of topoisomerase II (alpha and beta) in 29 choroidal melanomas for which chemosensitivity assay data for doxorubicin or mitoxantrone are also available. Of these, eight tumours were topoisomerase II beta-positive and 11 were topoisomerase II alpha-positive. Recent studies showing genetic abnormality (often monosomy of chromosome 3) in choroidal melanoma suggest that loss of immunostaining could be due to genomic loss rather than down-regulation of topoisomerase II beta in these tumours. There was no convincing excess of anthracycline resistance in the topoisomerase II beta-negative group. Addition of topoisomerase II alpha, MDR1 (11/17 positive), LRP (16/28 positive), and MRP (5/29 positive) data in multivariate analysis did not reliably predict sensitivity or resistance. Vincristine chemosensitivity showed no relation to MDR1, LRP or MRP in 18 tumours tested. While it is possible that some tumours which do express topoisomerase II beta may respond to anthracyclines, the molecular basis of resistance or sensitivity to anthracyclines or vincristine in uveal melanoma is complex and remains incompletely understood.

Exposure of primary orbital implants in postenucleation retinoblastoma patients

PURPOSE

To determine significant factors influencing the exposure of primary orbital implants in patients with retinoblastoma.

DESIGN

Retrospective noncomparative case series.

PARTICIPANTS

One hundred nine consecutive patients (110 sockets) who had undergone enucleation for retinoblastoma from January 1993 to December 1997.

METHODS

Two patients with recurrence of orbital retinoblastoma were excluded from further analysis, leaving 107 patients (108 sockets). The parameters analyzed included the patient's age; gender; ocular diagnosis; surgeon; type, covering, and size of the implant; the use of chemotherapy or radiotherapy; and the timing of these treatments in relation to enucleation. Study patients were divided into two main groups: the "treated group"-patients who had undergone adjuvant external beam radiotherapy or chemotherapy, and the "untreated group"-patients had undergone enucleation with or without cryotherapy, laser thermotherapy, or brachytherapy to the index or fellow eye. The following additional parameters were noted in the patients with exposed implants: time to exposure from date of enucleation and treatment of exposure.

MAIN OUTCOME MEASURE

Exposure of orbital implants.

RESULTS

There were two exposures caused by orbital recurrence of retinoblastoma. The rate of nontumor recurrence exposure was 28% (30 of 108). The median time to exposure was 136 days (range, 1-630 days). There were 18 exposures (35%,18 of 51) in the treated group, with a 34% exposure rate (13 of 38) in the chemotherapy group. The exposure rate was 21% (12 of 57) in the untreated group. The rates of exposure according to implant were: Vicryl mesh-wrapped hydroxyapatite (2 of 18, 11%), Medpor (8 of 13, 53%), plain polymethylmethacrylate (PMMA) (4 of 50, 8%), Mersilene-wrapped PMMA (9 of 17, 53%) and Castroviejo (7 of 10, 70%). Eight of the exposures (27%) were managed conservatively; the remainder required surgical repair.

CONCLUSIONS

Results suggested that implant type and covering (P = 0.000) had a highly significant effect on the rate of exposure in postenucleation retinoblastoma patients. There was no statistical evidence that age, gender, ocular diagnosis, surgeon, size of the implant, or radiotherapy had an effect on implant exposure. There was an increased rate of exposure in the chemotherapy group, although this did not achieve statistical significance (P = 0.058), but a detrimental effect could not be excluded.

Repair of late retinal detachment after successful treatment of retinoblastoma

PURPOSE

To analyze the results of vitreous surgery for late retinal detachment (RD) after successful treatment of retinoblastoma.

METHODS

The records of all patients with retinoblastoma seen at a single ocular oncology service between 1982 and 1998 were reviewed to identify patients treated for late RD. Previous treatments, characteristics of the RD, surgical techniques used, and visual and anatomic results of the surgery were recorded.

RESULTS

Of more than 500 charts reviewed, four patients treated for late RD were identified. All four had received previous, whole-eye, external beam radiotherapy and subsequently required cataract surgery. Other previous treatments included radioactive plaque, cryotherapy, xenon photocoagulation, and chemotherapy. At presentation, some patients had shifting subretinal fluid. None had a tear identifiable preoperatively, but two patients had a definite small slit tear at a tumor edge identified at surgery. One patient had a primary scleral buckle that failed. All patients had vitreous surgery with silicone oil. Average postsurgical follow-up was 30 months. Preoperative visual acuity ranged from 20/80 to light perception and improved postoperatively in two patients. The retina remained completely attached in three patients.

CONCLUSIONS

Despite shifting subretinal fluid and no identifiable tear, a rhegmatogenous RD should be considered if it occurs late in patients with otherwise stable, treated retinoblastoma. Tumor reactivation must be excluded carefully. Vitreous surgery can be used to repair the RD successfully and improve vision.

Delay in diagnosis of retinoblastoma: risk factors and treatment outcome

BACKGROUND

Delay in diagnosis of retinoblastoma causes considerable parental distress; however, the primary healthcare professional (PHP) may have difficulty detecting the most common presenting symptom-leucocoria. Alternatively, the PHP may not appreciate that retinoblastoma is the pathology underlying more common ocular symptoms in infants and young children.

METHOD

The parents of 100 recently diagnosed patients with retinoblastoma were interviewed to establish the extent of diagnostic delay, ascertain any associated risk factors, and to determine whether or not delay influenced treatment outcome.

RESULTS

Although nearly 50% of patients were referred to an ophthalmologist within 1 week of first consulting a PHP, one quarter waited more than 8 weeks. There was a significantly increased risk of diagnostic delay in younger patients, those presenting with squint rather than leucocoria, and those first presenting to a health visitor rather than to a general practitioner. The risk of local tumour invasion was significantly increased by diagnostic delay. Treatment with primary enucleation was not increased by diagnostic delay. There were no deaths during the study period.

CONCLUSION

Primary healthcare professionals require education about the importance of ocular symptoms, especially squint, in paediatric patients.

Comparison of episcleral plaque and proton beam radiation therapy for the treatment of choroidal melanoma

PURPOSE

To compare the efficacy of iodine-125 (125I) and ruthenium-106 (106Ru) episcleral plaque radiation therapy and proton beam radiation therapy (PBRT) in the treatment of choroidal melanoma.

DESIGN

A retrospective, nonrandomized comparative study.

METHODS

Charts of patients treated with 125I, 106Ru, and PBRT for choroidal melanoma between January 1988 and June 1996 at St. Bartholomew's Hospital and Moorfields Eye Hospitals were reviewed.

MAIN OUTCOME MEASURE

Local control of choroidal melanomas after 125I, 106Ru, or PBRT.

RESULTS

A total of 597 patients were identified (125I = 190, 106Ru = 140, PBRT = 267). Patients treated with 106Ru had a significantly greater risk of local tumor recurrence than did patients treated with either 125I (P = 0.0133; confidence interval [CI], 1.26-7.02; risk ratio, 2.97) or PBRT (P = 0.0097; CI, 1.30-6.66; risk ratio, 2.94). A stepwise Cox proportional hazard model found maximal basal diameter to be a significant covariate (P = 0.0033).

CONCLUSION

Patients treated with 106Ru had a significantly greater risk of local tumor recurrence than did those patients treated with either 125I or PBRT.

Predictive power of screening tests for metastasis in uveal melanoma

PURPOSE

Uveal melanoma undergoes haematogenous dissemination, particularly to the liver. It is routine practice to screen for metastatic disease. The purpose of this study was to evaluate such screening tests and to determine their value in detecting metastatic disease at presentation.

METHODS

In this study of a series of 245 patients with uveal melanoma of whom 55 (22%) died, the sensitivity, specificity, positive and negative predictive powers and likelihood ratio of the blood tests, chest radiographs and liver ultrasound investigations performed at diagnosis were determined.

RESULTS

All the screening investigations were found to have a low yield, but the most sensitive were those for gamma-glutamyl transpeptidase (gamma GT; sensitivity 21%) and alkaline phosphatase (sensitivity 25%), with gamma GT being more specific (specificity 92%). No blood test had a positive predictive power greater than 50%. The chest radiograph and liver ultrasonography were both 100% specific but had sensitivities of 2% and 14% respectively.

CONCLUSIONS

Only the chest radiograph and liver ultrasonography had positive predictive powers greater than 50% and these tests had very poor sensitivity. We conclude that there is no good test available for screening for metastatic uveal melanoma.

Proton beam therapy for posterior pole circumscribed choroidal haemangioma

BACKGROUND

Macular and juxtapapillary circumscribed choroidal haemangiomas (CCH) have always posed a diagnostic and therapeutic challenge. Proton beam therapy has been advocated by Zografos and associates as optimal for treating these tumours in this critical region as charged particles have a highly localised and uniform dose distribution.

PATIENTS

We present 3 cases of CCH treated with proton beam therapy. Two patients developed radiation optic neuropathy and maculopathy, and one had a persistent exudative macular detachment following treatment.

CONCLUSION

Our experience with proton therapy of these tumours has been disappointing in preventing radiation optic neuropathy and maculopathy and offers little advantage over external irradiation. The majority of our patients with this condition are now treated with low-dose lens-sparing external beam radiotherapy or brachytherapy, which has encouraging visual results and is a far more cost-effective option.

Modelling uveal melanoma

BACKGROUND/AIM

There has been no consistent pattern reported on how mortality for uveal melanoma varies with age. This information can be useful to model the complexity of the disease. The authors have examined ocular cancer trends, as an indirect measure for uveal melanoma mortality, to see how rates vary with age and to compare the results with their other studies on predicting metastatic disease.

METHODS

Age specific mortality was examined for England and Wales, the USA, and Canada. A log-log model was fitted to the data. The slopes of the log-log plots were used as measure of disease complexity and compared with the results of previous work on predicting metastatic disease.

RESULTS

The log-log model provided a good fit for the US and Canadian data, but the observed rates deviated for England and Wales among people over the age of 65 years. The log-log model for mortality data suggests that the underlying process depends upon four rate limiting steps, while a similar model for the incidence data suggests between three and four rate limiting steps. Further analysis of previous data on predicting metastatic disease on the basis of tumour size and blood vessel density would indicate a single rate limiting step between developing the primary tumour and developing metastatic disease.

CONCLUSIONS

There is significant underreporting or underdiagnosis of ocular melanoma for England and Wales in those over the age of 65 years. In those under the age of 65, a model is presented for ocular melanoma oncogenesis requiring three rate limiting steps to develop the primary tumour and a fourth rate limiting step to develop metastatic disease. The three steps in the generation of the primary tumour involve two key processes-namely, growth and angiogenesis within the primary tumour. The step from development of the primary to development of metastatic disease is likely to involve a single rate limiting process.

Combination chemotherapy for choroidal melanoma: ex vivo sensitivity to treosulfan with gemcitabine or cytosine arabinoside

Treatment of choroidal melanoma by chemotherapy is usually unsuccessful, with response rates of less than 1% reported for dacarbazine (DTIC)-containing regimens which show 20% or more response rates in skin melanoma. Recently, we reported the activity of several cytotoxic agents against primary choroidal melanoma in an ATP-based tumour chemosensitivity assay (ATP-TCA). In this study, we have used the same method to examine the sensitivity of choroidal melanoma to combinations suggested by our earlier study. Tumour material from 36 enucleated eyes was tested against a battery of single agents and combinations which showed some activity in the previous study. The combination of treosulfan with gemcitabine or cytosine arabinoside showed consistent activity in 70% and 86% of cases, respectively. Paclitaxel was also active, particularly in combination with treosulfan (47%) or mitoxantrone (33%). Addition of paclitaxel to the combination of treosulfan + cytosine analogue added little increased sensitivity. For treosulfan + cytosine arabinoside, further sequence and timing experiments showed that simultaneous administration gave the greatest suppression, with minor loss of inhibition if the cytosine analogue was given 24 h after the treosulfan. Administration of cytosine analogue 24 h before treosulfan produced considerably less inhibition at any concentration. While we have so far been unable to study metastatic tumour from choroidal melanoma patients, the combination of treosulfan with gemcitabine or cytosine arabinoside shows activity ex vivo against primary tumour tissue. Clinical trials are in progress.

Ring melanoma--a rare cause of refractory glaucoma

BACKGROUND

Ring melanoma of the ciliary body and iris is extremely rare and often has adverse histology. This tumour may cause raised intraocular pressure.

METHODS

A review of four cases of ring melanomas with insidious presentations seen in the ocular oncology service over a 12 month period.

RESULTS

All four patients presented with unilateral anterior segment abnormalities and refractory glaucoma. The misdiagnoses of the causes of the glaucoma included angle recession from previous blunt trauma (patient 1); iridocorneal endothelial (ICE) syndrome supported by endothelial specular microscopy (patients 2 and 3); and melanocytoma on ciliary body biopsy (patient 4). Two patients were treated by several cyclodiode ciliary body ablation treatments and the other two underwent trabeculectomies and Molteno tubes. Two of the four patients have since died from their disease.

CONCLUSION

The ophthalmologist should re-evaluate the diagnosis in patients with anterior segment abnormalities and refractory ipsilateral glaucoma. Endothelial specular microscopy and biopsy of the suspicious lesion may give misleading reassurance. The potential presence of an anterior uveal melanoma must always be considered.

c-myc, p53, and Bcl-2 expression and clinical outcome in uveal melanoma

AIMS

Overexpression of c-myc protein has independent prognostic significance in a variety of primary and metastatic cutaneous melanomas which suggests a possible role for this gene in melanomagenesis. We have therefore examined the importance of this oncogene in uveal melanoma and studied the coexpression of two other gene products, Bcl-2 and p53, which might contribute to its effect.

METHODS

The percentage of cells positive for nuclear c-myc expression was estimated by flow cytometric analysis of nuclei extracted from paraffin blocks. The expression of Bcl-2 and p53 protein was assessed by immunohistochemistry. A total of 71 tumours were studied and the results compared with survival with a mean follow up period of 6 years.

RESULTS

c-myc was expressed in > 50% of the cells by 70% of the tumours, and was independently associated with improved survival in a Cox multiple regression-model. Although Bcl-2 was expressed by the majority of the cells in 67% tumours, it was without effect on prognosis. None of the cases studied showed convincing positivity for p53. Analysis of coexpression showed that the best survival was seen in c-myc+/Bcl-2+ tumours and the worst in c-myc-/Bcl-2-tumours.

CONCLUSION

The finding of improved rather than reduced survival in c-myc positive tumours is at variance with skin melanoma. There was no evidence to suggest that c-myc was modulated by upregulation of Bcl-2 or p53 inactivation/mutation. Although Bcl-2 is unlikely to have any effect on tumour growth or metastasis, it could contribute to the general lack of susceptibility to apoptosis in these tumours.

The prognostic significance of c-myc oncogene expression in uveal melanoma

The role of the c-myc oncogene has been little investigated in uveal melanoma. In this study an analysis of c-myc oncoprotein expression was undertaken using flow cytometry in 71 patients with posterior uveal melanoma. Nuclear c-myc oncoprotein was detected in all of the tumours, and survival analysis revealed a significant association between high oncoprotein positivity and improved survival (log rank test: chi2 = 6.47, P = 0.01). Multifactorial analysis using Cox's proportional hazards model revealed nuclear c-myc oncoprotein to be an independent prognostic marker more accurate than other clinicopathological parameters (log rank test: chi2 = 6.61, P = 0.01). However, this result of high oncoprotein expression correlating with improved outcome is surprising and in contrast to our previous studies using the same method on cutaneous melanoma, where high levels of nuclear c-myc expression have been found to correlate with poor outcome both in primary and secondary disease. This study suggests that the pattern of oncogene expression in uveal melanoma is distinct from cutaneous melanoma and that the underlying biology of these tumours is different.

Treatment of retinoblastoma vitreous base seeding

OBJECTIVE

The purpose of the study is to describe results of a new treatment for retinoblastoma vitreous base seeding.

DESIGN

The study design was a retrospective review of patients treated at an ocular oncology referral center.

PARTICIPANTS

Five eyes of five patients with vitreous base seeding that occurred after previous external beam radiation therapy were treated between October 1987 and December 1994.

INTERVENTION

A customized plaque made from iridium-192/platinum wire was placed to deliver 4000 cGy to the tumor apex along its entire length and systemic chemotherapy (consisting of carboplatin, vincristine, and etoposide) was given.

MAIN OUTCOME MEASURES

Eye preservation and tumor control were measured.

RESULTS

Vitreous base seeding was controlled completely and the eye preserved in four of the five treated eyes with an average follow-up of 26.2 months.

CONCLUSIONS

The combination of a customized iridium-192 plaque and systemic chemotherapy is an effective means of treating vitreous base seeding of retinoblastoma.

Choroidal hemangiomas: visual and anatomic results of treatment by photocoagulation or radiation therapy

PURPOSE

Choroidal hemangioma is a benign hamartoma that causes accumulation of subretinal fluid and resultant visual loss. Although photocoagulation can result in resolution of subretinal fluid, some have found that recurrence is common and final visual acuity often is poor. The purpose of this study is to evaluate the visual and anatomic results of radiation therapy and photocoagulation in treating patients with visual loss from choroidal hemangiomas.

METHODS

A retrospective review was performed of patients with circumscribed choroidal hemangiomas (CCH) or diffuse choroidal hemangiomas (DCH) treated for visual loss caused by accumulation of subretinal fluid. Of 23 patients with CCH, 13 were treated by photocoagulation, 8 by plaque brachytherapy, and 2 by lens-sparing external beam radiation therapy (LSRT). All five patients with DCH were treated by LSRT.

RESULTS

Of patients with CCH treated by brachytherapy, six (75%) of eight had visual acuity of 6/12 or better at 1 year and 8 (100%) of 8 had no subretinal fluid. Of patients with CCH treated by photocoagulation, 5 (38%) of 13 had visual acuity of 6/12 or better at 1 year and 6 (46%) of 13 had no subretinal fluid. Of patients with CCH treated by LSRT, none of two had visual acuity of 6/12 or better at 1 year and one of two had no subretinal fluid. Of the five patients with DCH treated by LSRT, all had complete resolution of subretinal fluid. Two had marked visual improvement and in the other three, vision was stabilized.

CONCLUSIONS

Plaque brachytherapy is an effective alternative to photocoagulation for treatment of subretinal fluid caused by CCH. Lens-sparing external beam radiation therapy is effective treatment in patients with DCH.

Predictive factors for the development of rubeosis following proton beam radiotherapy for uveal melanoma

AIMS/BACKGROUND

Proton beam radiotherapy can effectively treat primary uveal melanomas of any size. Some patients, however, develop adverse late effects following treatment and the purpose of this study was to determine which factors give rise to a poor local outcome.

METHODS

The hospital records from a first cohort of 127 patients treated by protons from 1989 to 1992 were reviewed retrospectively. The presence of rubeosis was selected as a measure of significant ocular damage. Split file analysis was performed with 73 cases forming a test group with the remaining 54 cases acting as a validation group.

RESULTS

Large tumour size and the presence of retinal detachment were significant, independent risk factors for developing rubeosis for both the test and validation groups. These factors also predicted subsequent enucleation for uncontrolled ocular pain. Patients with tumours too large to plaque and with an associated retinal detachment had a 90% chance of developing rubeosis within 4 years of proton beam radiotherapy.

CONCLUSIONS

Patients with a uveal melanoma too large for plaque therapy and an associated retinal detachment run a very high risk of developing rubeosis after proton beam radiotherapy and one third of individuals developing rubeosis required enucleation for pain even if local tumour control was satisfactory.

Topical mitomycin C for the treatment of conjunctival and corneal epithelial dysplasia and neoplasia

PURPOSE

To evaluate the efficacy of topical mitomycin C in treating conjunctival and corneal epithelial dysplasia and neoplasia.

METHODS

Seven eyes of seven patients with conjunctival and corneal epithelial dysplasia and neoplasia were treated with one drop of topical mitomycin C 0.04% four times a day for 7 days in alternate weeks. The patients' charts were reviewed retrospectively. Patients with either multiple recurrences or extensive ocular surface involvement were treated. In all eyes, the diagnosis of epithelial dysplasia or neoplasia was confirmed by histopathology before the onset of therapy. Patients were examined at least every 14 days during treatment and examined at intervals after completion of treatment.

RESULTS

With topical mitomycin C, six eyes of seven patients had complete clinical regression of their conjunctival and corneal epithelial dysplasia and neoplasia. One eye of one patient had partial clinical regression of conjunctival and corneal epithelial dysplasia. Follow-up after completion of topical mitomycin C therapy and excision of residual disease ranged from 2 to 16 months (mean, 9 months; SD, 4.3 months) and was without clinical sign of recurrence. Topical mitomycin C therapy was associated with transitory ocular discomfort, conjunctival injection, tearing, photophobia, and punctate epithelial keratopathy.

CONCLUSION

In this small series of eyes, topical mitomycin C was effective as a treatment for conjunctival and corneal epithelial dysplasia and neoplasia.

The ex vivo chemosensitivity profile of choroidal melanoma

Uveal melanoma has a high mortality rate and responds poorly to existing chemotherapy. We have therefore examined the sensitivity of uveal melanoma to cytotoxic agents using an ex vivo chemosensitivity assay to determine whether some agents which have not been used for this tumor might have activity. An ATP-based tumor chemosensitivity assay (ATP-TCA) was used to determine the effect of nine cytotoxic drugs at multiple dilutions in 28 primary uveal melanoma specimens. Evaluable assay results from up to 16 tumors with each drug showed variable sensitivity to alkylating agents (three of nine with mitomycin C, one of 15 with cisplatin and seven of 15 with treosulfan), cytosine arabinoside (seven of 16), paclitaxel (one of five) and doxorubicin (two of 16). No tumors were sensitive to temozolomide, or 5-fluorouracil, and only one of 14 to vincristine. The combination of treosulfan with cytosine arabinoside resulted in enhanced tumor cell inhibition in three of five tumors tested. Combinations containing paclitaxel combined with doxorubicin or cisplatin showed some activity, but none achieved 100% inhibition and the results were similar to those obtained with paclitaxel alone. Uveal melanoma shows considerable heterogeneity of sensitivity to cytotoxic drugs, with considerable resistance to most agents, matching clinical experience. The results suggest that cytosine arabinoside or gemcitabine plus treosulfan may be an active combination. Clinical trials will commence shortly. The use of the ATP-TCA provides a method of testing multiple agents and combinations in a way which would be otherwise impossible in rare tumors such as uveal melanoma.

Reassessment of the PAS patterns in uveal melanoma

BACKGROUND

Previous work has highlighted the prognostic importance of patterns of periodic acid Schiff (PAS) staining (the Folberg patterns) in uveal melanoma. These patterns have been ascribed to blood vessels but the patterns are different from those seen with other staining techniques for blood vessels. It has recently been shown that microvessel density is the dominant prognostic factor in uveal melanoma. This study reinvestigates the nature and significance of the PAS patterns.

METHODS

The PAS patterns were compared with the patterns seen with conventional connective tissue stains and with the patterns seen in sections stained for the presence of blood vessels (by immunohistochemistry for factor VIII related antigen). The PAS patterns were determined on a panel of 117 cases of uveal melanoma. The prognostic significance of each of these patterns was determined and, as more than one pattern can exist in a tumour, principal components analysis was performed to determine the number of underlying factors.

RESULTS

Comparison of the PAS patterns with other stains demonstrates that they are based on connective tissue including fibrovascular tissue. Five of the nine PAS patterns carried prognostic significance on univariate analysis. Principal components analysis suggested that these patterns represented three underlying factors, which were tentatively identified as representing disordered growth (factor 1), emergence of rapidly growing subclones (factor 2), and section orientation (factor 3).

CONCLUSIONS

The PAS patterns are based on fibrovascular tissue and can be ascribed to three underlying factors. The first two of these factors carried prognostic significance and the first (disordered growth) retained independent prognostic significance in a multivariate Cox model which included microvessel density and tumour size.

The RB1 gene mutation in a child with ectopic intracranial retinoblastoma

The RB1 gene mutation was investigated in a child with ectopic intracranial retinoblastoma using DNA obtained from both the pineal and retinal tumours of the patient. A nonsense mutation in exon 17 (codon 556) of the RB1 gene was found to be present homozygously in both the retinal and the pineal tumours. The same mutation was present heterozygously in the DNA from the constitutional cells of the patient, proving it to be of germline origin. The initial mutation was shown to have occurred in the paternally derived RB1 allele. The mutation is in an area of the gene that encodes the protein-binding region known as the 'pocket' region and has been detected in other cases of retinoblastoma.

Results of combined chemotherapy and radiotherapy for advanced intraocular retinoblastoma

OBJECTIVE

To determine the visual anatomical results and survival after combined chemotherapy and whole eye radiotherapy for patients with bilateral Reese-Ellsworth group V retinoblastoma.

SETTING

A national referral center for retinoblastoma.

PATIENTS

Fourteen patients with bilateral Reese-Ellsworth group V retinoblastoma seen between March 1, 1989, and April 30, 1995, were treated.

INTERVENTIONS

Patients were treated with chemotherapy (using carboplatin, etoposide, and vincristine) and whole eye radiotherapy (40-44 Gy in 20-22 equivalent fractions). A medical record review was performed to determine outcomes.

MAIN OUTCOME MEASURES

Survival, eye preservation rate, and visual acuity.

RESULTS

Two patients died, 1 from a primitive neuroectodermal tumor and the other from the meningeal spread of retinoblastoma. Four eyes were enucleated primarily because of severe disease at presentation. Of the remaining 20 eyes, 6 required enucleation. The disease recurred in 4 of those patients, and neovascular glaucoma developed in 2 patients. Of the 12 surviving children, 5 have a visual acuity better than l/60 in at least 1 eye.

CONCLUSION

Although most of the treated group V eyes could be salvaged with chemotherapy plus radiotherapy, the resultant visual acuity was often poor.

Combining cyclosporin with chemotherapy controls intraocular retinoblastoma without requiring radiation

Chemotherapy without radiation has not controlled most intraocular retinoblastoma, perhaps because of the common high expression of multidrug resistance P-glycoprotein that we found in retinoblastoma. Cyclosporin blocks P-glycoprotein-induced efflux of vincristine and teniposide in vitro, and possibly modulates responses to carboplatin. To avoid eye irradiation in bilateral retinoblastoma patients with RB1 germline mutations, which incurs a high second malignancy rate, we added cyclosporin A to a vincristine-teniposide-carboplatin protocol and consolidated chemotherapy responses with focal therapy. We scored patients requiring irradiation, enucleation, or focal ablation of central vision as failures. In 21 study patients, the overall relapse-free rate at a median follow-up of 3.3 years was 76%, with a rate of 92% for newly diagnosed and 50% for previously treated, relapsed retinoblastoma. Our results for the most unfavorable tumors with vitreous seeds (86% at 3.5 years) are better than published success rates of irradiation for similar tumors, or irradiation with the same chemotherapy without cyclosporin (45% at 2. 6 years). These results also exceeded our historic success rate with similar chemotherapy without cyclosporin, focal therapy, and/or radiation in 19 equivalently poor-risk patients (relapse-free rate 37% at a median follow-up of 5.6 years, P = 0.032), 16 of whom were previously untreated (relapse-free rate also 37%, P = 0.012). A better outcome occurred with higher cyclosporin blood levels and projected tissue exposure. Cyclosporin did not enhance the usual chemotoxicity. This clinical study suggests that cyclosporin improves the long-term response of retinoblastoma to chemotherapy, possibly by more than one mechanism.

The role of cytology in the diagnosis of periocular basal cell carcinomas

The accurate diagnosis of eyelid tumors such as basal cell carcinoma (BCC) requires histological confirmation, usually obtained by biopsy. Cytology provides a rapid alternative that can yield a diagnosis during the initial outpatient appointment. The accuracy of this technique has been reported to be very good but its sensitivity in the diagnosis of periocular lesions is unknown. In order to assess the accuracy of cytology in eyelid lesions suspected clinically to be BCCs, the cytological and histopathological diagnoses were compared retrospectively in 20 lesions from 17 consecutive patients who underwent cytology followed by excision biopsy. The sensitivity of cytology for the diagnosis of BCC was 92% compared with 88% for the diagnosis of malignant tumor. The predictive accuracy was 75% for either diagnosis. This was compared with a second group of 26 clinical BCCs from 22 consecutive patients who had incisional biopsy and histological examination followed by excision with histological confirmation, in which case the sensitivity was 100% and accuracy 96%. It was concluded that cytology was sufficiently accurate to plan excision and reconstructive surgery, when a confirmatory tissue diagnosis can be made, but not sufficiently sensitive for conservative regimens such as radiotherapy because of the small risk of false negative diagnoses.

Microvessel count predicts survival in uveal melanoma

Microvessel density has become established as an important prognostic indicator for many tumor types. This study investigates the microvessel density as a prognostic factor for survival in patients with uveal melanoma, which is the commonest intraocular tumor and has a clear tendency for metastatic spread to the liver. Factor VIII-related antigen was identified immunohistochemically in bleached sections from 123 tumors. Maximum blood vessel density in an area of 0.25 mm2 was recorded, along with other accepted prognostic information. Microvessel density was the single most important prognostic factor on univariate testing, and in a Cox proportional hazard model, tumor size was the only other variable to be entered. No other accepted prognostic factor entered the model. We conclude that microvessel density is an important prognostic factor for survival in patients with uveal melanoma and allows the identification of high-risk patients for whom adjuvant therapy should be considered.

The detection of melanoma cells in peripheral blood by reverse transcription-polymerase chain reaction

Both cutaneous and uveal melanoma undergo haematogenous dissemination. Detection of tyrosinase mRNA by reverse transcription-polymerase chain reaction (RT-PCR) has been described as an extremely sensitive way of detecting circulating viable melanoma cells in the peripheral venous blood, and this technique may be of value in the early detection of dissemination. Also, it has been suggested that surgical manipulation of the eye, such as occurs during enucleation, can provoke uveal melanoma dissemination. The purpose of this study was to evaluate whether tyrosinase mRNA is detectable in the peripheral blood of patients with uveal and cutaneous melanoma and in patients with uveal melanoma undergoing surgical procedures on the eye harbouring the tumour. Venous blood samples from 36 patients diagnosed as having active uveal melanoma and from six patients with advanced metastatic cutaneous melanoma were analysed. In addition, blood samples were spiked with known numbers of cells from three cell lines and four primary uveal melanoma cultures. The reported sensitivity of the technique was confirmed, with an ability to detect down to one cell per ml of blood. All 51 blood samples from the 36 patients with uveal melanoma were negative, and this included 20 perioperative blood samples. The test was also negative for the six patients with advanced cutaneous melanoma. There were two positives among 31 control samples analysed. This study demonstrates that there are far fewer circulating viable melanocytes than has been previously supposed in patients with melanoma and that the RT-PCR is of no clinical value in detecting metastatic melanoma disease. There was no evidence for surgery causing a bolus of melanoma cells to enter the peripheral circulation.

Management of ocular melanoma

Most melanomas in the orbital region are primary tumours. The uveal tract is the commonest site though the skin of the eyelids, the conjunctiva and, very occasionally, the orbit itself may be involved. Direct spread may cause the tumour to present in an adjacent structure so that a uveal tract melanoma with an extrascleral nodule may appear to arise in the conjunctiva or in the orbit whilst a conjunctival melanoma may first be apparent in the adjacent eyelid skin. Metastatic deposits from cutaneous melanoma may occasionally present in the eye or ocular adnexa.

Retinoblastoma in association with the chromosome breakage syndromes Fanconi's anaemia and Bloom's syndrome: clinical and cytogenetic findings

Two children presenting with sporadic unilateral retinoblastoma and exhibiting a high degree of chromosome breakage were noted to have unusual facies, microcephaly and abnormal skin pigmentation. In the first child the pattern of both spontaneous and mitomycin-C-induced chromosome breakage was characteristic of Fanconi's anaemia although the degree of breakage was extreme. She also exhibited a striking increase in X-ray-induced chromosomal damage in G0 lymphocytes as measured by dicentric formation and increase in chromatid-type aberrations. She had a number of typical clinical features, including cafe-au-lait patches and abnormalities involving the kidney; however, she demonstrated neither the hypoplasia of radius and thumb nor the typical aplastic phase of this disorder. At age 22 months the child became anaemic with trilineage myelodysplasia, which was rapidly followed by the development of acute myeloblastic leukaemia. The early onset (at age 4 months) of retinoblastoma may have been associated with the underlying genomic instability. The second child exhibited a pattern of chromosome breakage characteristic of Bloom's syndrome, in addition to a moderate increase in damage induced by mytomycin-C. She had the typical stunted growth and malar hypoplasia of Bloom's syndrome although she did not demonstrate the frequently described erythematous 'butterfly rash' Although patients with Fanconi's anaemia and Bloom's syndrome are recognised to be at an increased risk of cancer, retinoblastoma has not previously been described in patients with either condition. We suggest that underlying recessive chromosome breakage syndromes may be underdiagnosed in paediatric cancer patients, with important implications for prognosis and genetic counselling.

Risk of ocular melanoma in relation to cutaneous and iris naevi

A case-control study was set up to assess the risk of eye melanoma in relation to the number and type of cutaneous melanocytic naevi and pigmented lesions of the iris. Cases comprised 211 unselected ocular melanoma patients attending the Ocular Oncology Clinic at Moorfields Eye Hospital, London, during November 1990 to October 1991 and diagnosed after August 1986. Hospital and general practice controls (416) were recruited in the North East Thames Region of the UK. Cutaneous naevi greater than or equal to 2 mm in diameter were counted on the skin. Clinically atypical and congenital naevi were recorded separately. Pigmented lesions of the iris were counted. The relative risk for ocular melanoma increased with numbers of atypical naevi and numbers of common naevi. Ten percent of cases but 3% of controls had at least 100 naevi of 2 mm or greater diameter. Seven percent of cases and 0.4% of controls had 4 or more atypical naevi. Pigmented lesions of the iris were significantly more common in cases than controls. Nine percent of cases had the Atypical Mole syndrome (AMS) phenotype compared with 1% of controls. Six cases had concurrent cutaneous melanoma primaries. We conclude that atypical and iris naevi are important risk factors for eye melanoma and that patients with eye melanoma are at increased risk of cutaneous melanoma. Dermatological examination for the AMS phenotype and cutaneous melanoma should be recommended in eye melanoma patients with large numbers of pigmented lesions of the skin or family history of melanoma.

Estrogen and progesterone receptor analysis in ocular melanomas

BACKGROUND

It has been suggested that pregnancy may promote metastases in melanoma and that the contraceptive pill may be an etiologic factor. The purpose of this study is to determine if uveal or conjunctival melanomas express estrogen or progesterone receptors.

METHODS

Twenty-seven choroidal and five conjunctival melanomas were investigated. Immunohistochemistry was performed using the antibodies ER-D5, which recognizes heat-shock protein 27 (formerly called the estrogen receptor-associated cytoplasmic antigen); ER-1D5, which recognizes the estrogen receptor; and PgR, which recognizes the progesterone receptor.

RESULTS

Most of the conjunctival and uveal melanomas stained strongly for heat-shock protein 27 but none of the tumors showed positive nuclear staining for either the estrogen or the progesterone receptor.

CONCLUSIONS

No evidence was found for either estrogen receptor or progesterone receptor expression in choroidal or conjunctival melanomas. Based on the literature, there is little evidence for these hormones having a role in the development or progression of these tumors.

External beam radiotherapy for retinoblastoma: II. Lens sparing technique

A retrospective analysis is presented of the results of external beam radiotherapy for retinoblastoma utilising an accurate lens sparing technique. Local tumour control has been assessed in a consecutive series of 67 eyes in 53 children all of whom received external beam radiotherapy as the primary treatment of retinoblastoma. Follow up ranged from 12 to 82 months (median 35 months) with 76% of the children followed for more than 2 years. Tumour control rates have been analysed with respect to the Reese-Ellsworth classification. The role of adjuvant and salvage focal therapy is emphasised. Following lens sparing radiotherapy with prior adjuvant treatment of anterior tumours, where appropriate, the overall ocular cure rate was 72%. With salvage therapy of persistent, recurrent, or new tumours, 93% of eyes could be preserved in this series which includes mainly eyes classified in Reese-Ellsworth groups I-III. These results compare favourably with those of whole eye external beam radiotherapy for comparable tumours, and with those of lens and anterior segment sparing using other techniques. They were achieved without the ocular morbidity associated with whole eye external beam radiotherapy.

External beam radiotherapy for retinoblastoma: I. Whole eye technique

A retrospective analysis has been performed of the results of external beam radiotherapy for retinoblastoma using a whole eye technique. Local tumour control has been assessed in a consecutive series of 175 eyes in 142 children all of whom received external beam radiotherapy as the primary treatment for retinoblastoma. Follow up ranged from 2 to 17 years (median 9 years). Tumour control rates have been analysed with respect to the Reese Ellsworth classification and the series includes eyes in groups I to V. Focal salvage therapy was given for persistent, recurrent, or new tumours after radiotherapy. Following whole eye radiotherapy alone, the overall ocular cure rate was 57%, though with salvage therapy 80% of eyes could be preserved.