Current approaches to the diagnosis and management of retinoblastoma

Ruptured retinoblastoma: management in a rare case scenario

A preschool child presented with white reflex in left eye since 2 months. Examination under anaesthesia revealed left eye retinoblastoma group D as per international classification of retinoblastoma. In collaboration with medical oncologist, systemic chemotherapy was started. After two cycles of systemic chemotherapy, tumour ruptured into the vitreous cavity suspending the tumour cells in the vitreous jelly. After a combination of systemic and intravitreal chemotherapy with adjuvant transpupillary thermotherapy of the residual retinal tumour, retinoblastoma regressed completely with corresponding flat scar.

Retinoblastoma in the Presence of Persistent Fetal Vasculature

Purpose:

This work aims to report the challenging diagnosis, treatment, and follow-up of a patient with persistent fetal vasculature (PFV) and retinoblastoma (RB).

Methods:

A 22-month-old boy presented with unilateral RB stage VB in the right eye and PFV in both eyes. The patient was treated with transpupillary laser ablation and systemic chemotherapy.

Results:

Treatment resulted in complete tumor regression. Two years after the last systemic chemotherapy treatment, magnetic resonance imaging (MRI) showed increased signal intensity with progressive optic nerve enhancement, where intraneural malignancy could not be excluded. Enucleation of the right eye was performed. Histopathologic review showed no residual active malignancy in the enucleated globe.

Conclusions:

This case demonstrates the importance of a thorough clinical examination to establish the correct diagnosis and to rule out RB before any surgery. This case also highlights the importance of regular follow-ups after tumor regression with full a ophthalmologic examination, B-scan, and periodic MRI.

Heterochromia irides and mistaken identity of retinoblastoma

Retinoblastoma is the most common intraocular malignancy of infancy which frequently manifests with a white pupillary reflex. We report a case of delayed presentation of a child with retinoblastoma in his left eye because parents thought the change in iris colour in this eye was due to the innocent heterochromia irides that was previously diagnosed in his elder sibling. This late presentation necessitated enucleation of the affected eye followed by chemotherapy.

Proton Beam Irradiation for Treatment of Experimental Human Retinoblastoma

Proton beam irradiation was used to treat human retinoblastoma (Y-79 cell line) grown subcutaneously in the athymic "nude" mouse. Thirty-four tumors were included in the experimental groups, of which twenty-three were irradiated and eleven served as controls. Tumors were irradiated with protons produced at the 160 megavolts Harvard cyclotron. The dose delivered to the tumor ranged from 7.5 to 27.5 proton gray in a single treatment, and 25.0 proton gray delivered in two fractions separated by 24 hours. Reduction of tumor growth was significantly greater than controls (p less than 0.001) with treatment doses greater than or equal to 17.5 proton gray. Histologic examination revealed a marked decrease of mitotic activity in all specimens examined 48 hours after treatment at these higher doses. Total regression without evidence of remaining malignant cells was noted in three tumors treated at 17.5 proton gray or above. Our results indicate that human retinoblastoma in a murine host, with a tumor mass similar to that seen in a clinical setting, is sensitive to radiation by high energy protons.

Destruction of the craniofacial skeleton in the child caused by an orbital tumor

PURPOSE

The aims of this paper are to describe the morphological alterations within an infant craniofacial skeleton caused by an orbital tumor and present how the bone reacts in contact with a spreading tumor mass.

METHODS

A study was performed on the dry skull of a child at the age of approximately 2 years. Morphological alterations of the craniofacial skeleton were analysed by visual inspection, and the intracranial cavity was examined with the aid of a digital camera. Subsequently, the skull was examined using computed tomography.

RESULTS

The skull was identified as having unilateral symptoms of orbital destruction caused by a malignant tumor, probably retinoblastoma or rhabdomyosarcoma. The left orbit and surrounding bones showed extensive malformation caused by the invading tumor. Profound deformities were also observed in the nasal cavity, which was partially occluded by the collapsed medial wall of the left orbit. The tumor extended to the wall of the orbit, spread out of the orbit, penetrated to the anterior cranial fossa, and probably invaded the brain.

CONCLUSIONS

Extensive pathological cranial destruction and possible metastases to inner organs suggest that the orbital tumor was the cause of death. Anatomical alterations observed in the craniofacial skeleton indicate a highly aggressive character of the orbital tumor.

In vitro moxifloxacin drug interaction with chemotherapeutics: implications for retinoblastoma management

Retinoblastoma (RB) is a common malignant intraocular tumor primarily affecting children. Multidrug resistance (MDR) proteins (P-gp and MRPs) mediated chemoresistance have been considered as a major cause of treatment failure in treatment of RB. Ocular cells have shown good tolerability against moxifloxacin (MFX). Hence, the aim of present study was to investigate the effect of moxifloxacin on the functionality of MDR proteins. Furthermore, we have also examined an interaction of MFX with anticancer agents (Topotecan, etoposide and vinblastine) for RB treatment. For interaction of MFX with efflux transporter, model cell lines transfected with the efflux transporters (MDCK-MDR1 and MDCK-MRP2) were used to perform uptake and bi-directional transport experiments. Modulation of anticancer induced cell cytotoxicity, pro-inflammatory cytokines (IL-6 and IL-8) release and caspase-3 enzyme activity in presence of MFX was also evaluated. Result indicates that MFX is a substrate of both MDR1 and MRP2 efflux transporters. Furthermore elevation of anticancer uptake and bi-directional transport, reduction in IC50 cytotoxic value and modulation of antiproliferative and cytokines release in presence of MFX by anticancer agents was observed. Our results demonstrate that MFX may not only modulate the permeability of anticancer agents at efflux sites but it may also potentiate antiproliferative activity of anticancer agents in retinoblastoma cells. This study may be further extended to explore in vivo outcome of this finding.

Retinoblastoma: the challenges of management in Ibadan, Nigeria

BACKGROUND

Retinoblastoma is a common highly malignant tumor of the eye. Late presentation leads to poor survival rate in many developing countries.

OBJECTIVE

To identify problems associated with management of retinoblastoma.

METHODS

A retrospective review of cases of retinoblastoma at the University College Hospital, Ibadan, between January 1992 and December 2007.

RESULTS

A total of 32 eyes of 26 patients were studied. Sixteen were males and 10 were females. Minimum age at presentation was 4 months and maximum age was 60 months (mean 30.69+/-14.2 mo). Over 90% presented after 1 month of onset. Reasons for late diagnosis included late presentation for unknown reasons, missed diagnosis, and mismanagement in a previous hospital. Eleven of 26 patients defaulted to avoid removal of the eye, and treatment was only completed in 5 patients. Problems included financial constraint regarding investigations and procurement of drugs, as well as availability of the chemotherapy.

CONCLUSIONS

Retinoblastoma is a problematic malignancy of childhood associated with management problems often related to difficulty with patients accepting removal of the affected eye and financial constraint for treatment.

Presumed transient reactive astrocytic hyperplasia in immature retina

PURPOSE

To describe the appearance and clinical course of small, white, endophytic calcific, peripheral lesions in developing retina of premature infants.

METHODS

Retrospective review of all patients evaluated for retinopathy of prematurity (ROP) at a level I neonatal intensive care unit (NICU) in San Jose, CA, between January 1, 2003, and December 31, 2004. Patients were examined either in the NICU or the affiliated outpatient clinic. Clinical examination consisted of dilated fundus examination with 360 degree scleral depression. Lesions were identified if they were white, calcific, peripheral, and transient. Ancillary testing and examination of family members was performed as indicated.

RESULTS

A total of 302 unique patients were screened for ROP. Ten lesions were identified in seven eyes. Three eyes had two lesions each. All lesions were unilateral. The size of the lesions was estimated to range between 500 and 700 microm. All lesions were located anterior to the vascularized retina, had minimal elevation on scleral depression, and demonstrated a predilection for the nasal and temporal raphe. Ultrasound findings demonstrated an elevated, hyperechoic mass with orbital shadowing. Computed tomography and magnetic resonance imaging tests did not demonstrate the lesions. Lesions involute slowly over a period of 6 months. There were no systemic findings or familial dispositions.

CONCLUSION

Immature retina in premature infants may predispose to the formation of transient reactive astrocytic hyperplasia. Development of mature retinal vascularization and spontaneous resolution of lesions should alleviate concerns regarding a more malignant diagnosis.

Retinoblastoma

BACKGROUND: Retinoblastoma is the most common intraocular malignancy of infants and children. With early diagnosis and treatment, survival is greater than 90%; however, patients with a germline retinoblastoma mutation have a substantial risk of having a second high-grade malignancy. METHODS: The recent developments in the diagnosis and treatment of retinoblastoma are reviewed. RESULTS: Identification of the retinoblastoma germline mutation is now possible with the discovery of the retinoblastoma gene. Patients with the germline mutation have a 51% cumulative risk over 50 years of developing a second malignancy. Several pilot studies using primary chemotherapy for retinoblastoma have shown promising results. CONCLUSIONS: Risk assessment and genetic counseling have become more precise with the development of laboratory methods to identify the retinoblastoma gene. The development of primary chemotherapy regimens to reduce the size of retinoblastoma tumors may decrease the need for radiation therapy and thereby reduce the risk of radiation-related malignancies in patients with the germline mutation.

Multiple malignancies in a patient with bilateral retinoblastoma

A case is presented of a patient with bilateral retinoblastoma, treated at infancy with surgery, chemotherapy and radiotherapy, who subsequently developed at least four additional histologically distinct malignancies: a Ewing sarcoma of the left fibula, two extraskeletal osteosarcomas of the left lower extremity, a mucoepidermoid carcinoma of the right parotid gland and a squamous cell carcinoma of the left paranasal cavity. In addition to retinoblastoma, patients with a germline RB-1 mutation are at high risk of second primary malignancies. An additive carcinogenic effect of cytotoxic therapy in these patients has been assumed. Patients with hereditary retinoblastoma should be under life-long follow-up programmes including a regular head and neck examination for detection of new primaries, especially in the radiation field of the presenting retinoblastoma.

Radiation therapy for retinoblastoma: a retrospective review of 120 patients

PURPOSE

To characterize the patient population and treatment outcomes in patients with Retinoblastoma (RB) referred for External Beam Orbital Radiotherapy (EBORT) to King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, Saudi Arabia from 1976 to 1993.

METHODS AND MATERIALS

A retrospective study of 120 patients with RB affecting a total of 192 eyes. Patients were divided into three groups. Group A are 60 patients (64 eyes) treated with EBORT to the intact eye to preserve vision. Reese-Ellsworth (RE) Staging was: 1: 12%; 2: 10%; 3: 12%; 4: 23%; and 5: 43%. Twenty-eight patients (47%) also received Vincristine, Adriamycin, and Cyclophosphamide chemotherapy (C/T). Mean follow-up, per patient, was 48.5 months. Standard treatment until 1992 was 45 Gy in 12 fractions of 3.75 Gy, three times weekly over 18 days. Assuming the alpha/beta ratio for early effects and tumor control at 10, Tk = 21 days, Tpot = 5 days, then the Biological Equivalent Dose (BED) was 62 Gy10 for early effects, and 101 Gy3 for late effects. Group B are 28 patients (28 eyes) treated for curative intent with EBORT to the orbit for locally advanced disease, usually after enucleation (24 eyes). Nineteen patients (83%) also had C/T. Mean follow-up was 22.6 months. Group C are 37 patients with advanced disease treated with radiotherapy for palliation. Seventeen (46%) also received C/T. Mean follow-up was 11.7 months.

RESULTS

Group A-following EBORT useful vision was retained in RE Stage 1 to 5: 7 of 7, 6 of 6, 4 of 8, 10 of 15, and 7 of 28 eyes, respectively. There was no significant difference between patients who received adjuvant chemotherapy and those who did not. Complications included cataract (27%), retinopathy (25%), vitreous hemorrhage (19%), and orbital deformities (11%). In Group B the local control rate was 71%. In Group C, 10 (27%) of the 37 patients were alive at last contact, and 27 (73%) were either terminal or dead of disease. None of Group A or B patients had positive CSF cytology, bone scan, or bone marrow examination. In Group C 19% had positive CSF cytology, and bone marrow, and 14% had a positive bone scan.

CONCLUSIONS

1) EBORT preserved useful vision in a significant proportion of patients even in eyes with advanced RE Stage RB, but longer follow-up is likely to reveal an even higher complication rate with this regime. 2) High dose per fraction probably contributed to the increased complications. 3) Chemotherapy did not demonstrate any effect on retaining vision in this study. 4) For disease that is confined to within the eye clinically and radiologically, invasive procedures for CSF cytology, bone marrow examination, and bone scan do not seem warranted. 5) The optimum technique, fractionation, and dosage for RB is still not well defined.

Retinoblastoma in Turkey: diagnosis and clinical characteristics

Retinoblastoma (RB) is the most frequent malignant intraocular tumor in childhood. Six hundred and thirty-six cases with 831 RB-affected eyes were diagnosed and treated in our specialist center between 1963-1994. The diagnosis was made by histopathologic examination in 617 cases and clinically in 19 cases. Four hundred and forty-one (69.3%) cases were unilateral and 195 (30.7%) were bilateral. Two hundred and sixty-eight (42.1%) were females and 368 (57.9%) were males. The youngest patient was 20 days old and the oldest was 16 years old at the time of diagnosis (mean: 2.2 years). In thirty-four (5.3%) cases, a family history of RB was present. Ten of these cases were unilateral and 24 were bilateral. The most frequent presenting signs were leukocoria (394 cases, 61.9%), buphthalmos (92 cases, 14.5%), and strabismus (68 cases, 10.7%). The referring initial diagnoses were correct in 519 (81.6%) cases and false-negative in 117 (18.4%) cases. The most frequent initial false-negative diagnoses of the referring physicians were buphthalmos (43 cases, 6.8%), endophthalmitis (37 cases, 5.8%), and retinal detachment (12 cases, 1.9%). Apart from these 636 cases, there were 29 false-positive RB diagnoses during the same study period for which enucleation was performed. False-positive diagnoses included endophthalmitis (9 cases), retinal dysplasia (6 cases), retinal detachment (5 cases), vitreous hemorrhage (4 cases), Coats' disease (4 cases), and toxocariasis (one case). Ancillary testing for metastasis was carried out in all cases with newly diagnosed retinoblastoma. Five hundred and ninety-eight (72%) eyes had intraocular disease and 233 (28%) had extraocular spread. Of these 233 RBS, 58 had systemic disease. Fifty-two out of 58 tumors showing systemic involvement had either optic nerve or extrascleral extension at the histopathologic examination of enucleation material. The remaining six eyes had intraocular Class IV-V RB.

Quantification of orbital and mid-facial growth retardation after megavoltage external beam irradiation in children with retinoblastoma

PURPOSE

The late side effects of external beam irradiation in patients with retinoblastoma such as orbital bony growth retardation, are a serious problem in adolescence. Therefore, a quantitative study was performed to investigate the late effects of irradiation on orbital growth in patients with retinoblastoma.

METHODS

The orbits of 68 patients with retinoblastoma, 52 bilateral and 16 unilateral, were divided into two treatment groups: radiotherapy alone, 77 orbits; and radiotherapy + enucleation, 43 orbits. Follow-up time was 12 to 240 months (mean, 95 months) in group 1 and 27 to 216 months (mean, 97 months) in group 2. These groups were subdivided further into age groups at which radiotherapy was given. The morphometric measurements of these groups were compared.

RESULTS

The authors showed that irradiation causes a significant growth retardation when compared with the growth of nonirradiated orbits (P<0.001). They also demonstrated that radiotherapy in children younger than 6 months of age is more damaging to the orbital growth than at an older age (P<0.01). Finally, the authors showed that secondary enucleation does not have an additive growth-retarding effect.

CONCLUSION

Orbital growth retardation in patients with retinoblastoma after radiotherapy is influenced mainly by the age at which irradiation is given and is defined at 6 months. Theoretically, it would be desirable to postpone irradiation in children until they are older than 6 months of age if possible. The irradiation effect on these orbits is not enhanced by enucleation.

Immunohistochemical evidence of neuronal and glial differentiation in retinoblastoma

BACKGROUND

The study sought to investigate the histogenesis of retinoblastoma.

METHODS

One hundred specimens of retinoblastomas were examined along with those of 18 astrocytic gliomas and 15 medulloblastomas to compare similarities of glial differentiation in retinoblastoma and the two types of brain tumour. Employing avidin-biotin immunoperoxidase technique, antibodies were applied against neuron specific enolase (NSE), glial fibrillary acidic protein (GFAP), and S-100 protein (S-100).

RESULTS

Most rosettes and fleurettes, and some undifferentiated cells in retinoblastomas were NSE positive, but GFAP and S-100 negative. GFAP and S-100 positive cells in retinoblastomas were detected mostly in well differentiated glial cells which were interpreted as reactive or non-neoplastic cells. Some of the GFAP and S-100 positive cells in retinoblastomas were defined as tumour cells that resembled neoplastic astrocytes in astrocytic gliomas and medulloblastomas.

CONCLUSION

Retinoblastoma may arise from primitive bipotential or multipotential cells capable of neuronal and glial differentiation.

Ultrasonic findings in intraocular retinoblastoma and correlation with histopathologic diagnosis

A and B-scan ultrasonographic records of 132 eyes of 126 patients with suspected retinoblastoma were evaluated retrospectively. Six patients had bilateral lesions. The results were compared with the histopathologic diagnoses obtained after enucleation in 129 cases and with the indirect ophthalmoscopic examination in 3 bilateral cases. Ultrasonographic diagnosis was correct in 115 cases (87.12%), false-negative in 12 cases (9.09%) and false-positive in 5 cases (3.79%). Echographic tumor typing was made in 88 cases and the mixed tumor type was the most frequent with 74 cases (84.09%). Cystic, solid and diffuse infiltrating types were the other echographic diagnoses. Our experience confirms the accuracy of ultrasonography in the diagnosis of retinoblastoma.

Visual outcomes of macular retinoblastoma after external beam radiation therapy

PURPOSE

To determine the risk factors that influence the visual outcomes of patients with macular retinoblastoma who are treated with radiation therapy.

METHODS

The medical records of all patients with macular retinoblastoma treated with radiation therapy between 1980 and 1990 were reviewed. Ten patients were entered into the study. Features analyzed included patient age, laterality of eye involvement, location and size of macular tumor(s) at the time of diagnosis, treatment course, and most recent visual acuity.

FINDINGS

Ten of 11 eyes (10 patients) were successfully treated with external beam radiation. Eight patients obtained visual acuities ranging from 20/25 to 20/100; two patients had visual acuities of 20/200 or less. The best visual acuities were noted in patients whose tumor(s) did not involve the fovea and were relatively small. The worse visual acuities were noted in patients with binocular vision whose tumors invaded the fovea and were larger in size. In two of three patients in whom both eyes were retained, superimposed amblyopia developed in the eye with macular retinoblastoma.

CONCLUSION

The authors' findings indicate that most patients with macular retinoblastoma who are treated with external beam radiation have favorable visual outcomes, but final visual acuity depends on the size of the tumor and involvement of the fovea. Patients in whom both eyes are retained are predisposed to further visual loss from amblyopia.

The toxic effects, GSH depletion and radiosensitivity by BSO on retinoblastoma

Retinoblastoma is the most common intraocular malignant tumor in children. Previous investigations have reported that buthionine sulfoximine (BSO) can deplete intracellular glutathione (GSH) by specific inhibition and increase cellular radiosensitivity. The toxic effects, GSH depletion and radiosensitivity of BSO on retinoblastoma cells are reported in this paper. GSH content of retinoblastoma cell lines Y-79, So-Rb50 and retinoblastoma xenograft is 2.7 +/- 1.3 x 1.0(-12) mmol/cell, 1.4 +/- 0.2 x 1.0(-12) mmol/cell, and 2.8 +/- 1.2 mumol/g, respectively. The ID50 of BSO on Y-79 and So-Rb50 in air for 3 h exposure is 2.5 mM and 0.2 mM, respectively. GSH depletion by 0.1 mM BSO for 24 h on Y-79 cells and 0.01 mM BSO for 24 h on So-Rb50 cells is 16.35%, and 4.7% of control. GSH depletion in tumor and other organ tissues in retinoblastoma-bearing nude mice after BSO administration is differential. GSH depletion after BSO exposure in Y-79 cells in vitro decreases the Do value of retinoblastoma cells. The SER of 0.01 mM and 0.05 mM BSO for 24 h under the hypoxic condition is 1.21 and 1.36, respectively. Based on these observations, the authors conclude that BSO toxicity on retinoblastoma cells depends on the characteristics of cell line and that BSO can increase hypoxic retinoblastoma cells' radiosensitivity in vitro. Further study of BSO radiosensitization on retinoblastoma in vivo using nude mouse xenograft is needed.

An experience of the use of radioactive plaques after failure of external beam radiation in the treatment of retinoblastoma

The authors have reviewed the results of radioactive plaques in recurrent retinoblastoma after external beam radiation in 34 eyes. They give their results on ocular conservation and on the visual outcome and compare these results with other series previously published. They think radioactive plaques are an alternative to enucleation in recurrent retinoblastoma after external beam.

Calcification of scleral-wrapped orbital implant in patients with retinoblastoma

Calcification detected by CT is a valuable technique to confirm a clinical impression of retinoblastoma. However, when calcification is detected following enucleation with placement of a scleral-wrapped orbital implant, the presence of calcium may be dystrophic, instead of indicating recurrent tumor growth. Cautious follow-up is warranted, and this report suggests that such calcification, probably associated with the scleral wrapping, can remain stable over many years.

Relationship of regression pattern to recurrence in retinoblastoma

A retrospective analysis has been conducted of regression patterns following treatment of retinoblastoma by external beam irradiation. There were 180 tumours in 105 eyes of 83 patients. Type I regression was found to be the commonest pattern and occurred in 50% of cases. Initial tumour size was found to be the only statistically significant determinant of regression pattern (p < 0.01). Thirteen tumours (7%) recurred within a median interval to recurrence of 12 months. All recurrences occurred within 40 months of completion of treatment and none occurred after age 4 years. No tumour less than 6 mm in diameter recurred. Although 10 out of 13 recurrences were of Type I, Cox model regression analysis showed initial tumour size to be the only independent predictor of recurrence (p < 0.01).

A reassessment of histologic classification and an immunohistochemical study of 88 retinoblastomas. A special reference to the advent of bipolar-like cells

BACKGROUND

Despite perpetual efforts of investigators, the histogenesis of retinoblastoma is still in dispute and histologic classification satisfactorily predictive of prognosis does not seem to be in use.

METHODS

The authors studied 88 cases of retinoblastoma clinicopathologically and immunohistochemically, paying special attention to the presence of a "bipolar-like cell" element that would be used as one of the criteria for the diagnosis of differentiated retinoblastoma.

RESULTS

Twelve cases of retinoblastoma with the bipolar-like cell element in the absence of rosettes and 41 cases of the tumor with rosettes were classified as differentiated retinoblastomas. The other 35 cases without rosettes or bipolar-like cells were classified as undifferentiated tumors. Tumor cells forming rosettes usually had positive results for synaptophysin and neuron-specific enolase (NSE) and negative results for glial fibrillary acidic protein (GFAP) and S-100 protein; however, undifferentiated cells had negative results for these four antibodies. The bipolar-like cells had positive results for synaptophysin and NSE but negative results for GFAP and S-100 protein. Twelve tumors with bipolar-like cells that lacked rosettes showed no optic nerve invasion, and the patients had a significantly better prognosis (100% 5-year survival rate) than 35 patients with undifferentiated tumors (71% 5-year survival rate) (P < 0.01).

CONCLUSIONS

The findings support a neuronal origin of the tumor and indicate that, not only the rosettes symbolizing the photoreceptor differentiation, but also other neuronal elements, such as bipolar-like cells, can be used as criteria for histologic classification of retinoblastoma.

Retinoblastoma in the first year of life

Children diagnosed with retinoblastoma in the first year of life present with differences in laterality, stage, signs, symptoms, and respond differently to treatments when compared to older children. Of those children diagnosed in the first year of life (between 1958 and 1983 inclusive), 280 were bilateral and 121 were unilateral, the most common stage of diagnosis (for unilateral and bilateral) was Group V, and children were affected equally by sex. Children examined in the first three months of life were more often seen because of a positive family history of retinoblastoma, rather than leukocoria. Children who were treated in the first year of life frequently develop second nonocular tumors because they harbor the germinal mutation and receive radiation.

Tumoricidal capacities of macrophages photodynamically activated with hematoporphyrin derivative

Four days after administration to mice of small amounts (30-600 ng/mouse) of hematoporphyrin derivative (HPD), peritoneal macrophages exhibited a greatly enhanced Fc-receptor mediated phagocytic capacity as assayed by ingestion activity of IgG-coated sheep erythrocytes. Much higher doses (greater than 3000 ng/mouse) did not have this effect. The peritoneal macrophages activated by administration of HPD have tumoricidal capacity for IgG-coated retinoblastoma cells. We then studied in vitro photodynamic activation of macrophages by white and red fluorescent light irradiation of mouse peritoneal cells (mixture of macrophages and B and T lymphocytes) in media containing very low concentrations of HPD. A short (5 s) white fluorescent light exposure (1Wm-2) of peritoneal cells in a medium containing 0.03 ng HPD/mL produced the maximal level of ingestion activity of macrophages. A 15 s red fluorescent light exposure (1Wm-2) of peritoneal cells in a medium containing 0.1 ng HPD/mL produced the maximal level of ingestion activity of macrophages. Thus, photodynamic activation of macrophages with white fluorescent light is more efficient than that with red fluorescent light. This can be explained by the fact that HPD has a large absorption peak at about 364 nm which extends into the visible range, and decreasingly smaller absorption bands at 500, 535, 570 and 630 nm. In vitro photodynamically activated macrophages showed efficient tumoricidal activity regardless of the type (white or red) of light used. These results suggest that a low level of HPD promotes therapeutic immunopotentiation.

Visual acuity after successful treatment of large macular retinoblastoma

Recent trends in the treatment of retinoblastoma have favored radiation therapy as opposed to enucleation. A major determining factor in selecting radiation therapy is the possibility of useful posttreatment visual function. While the treatment of nonmacular tumors seems reasonable, little information is available about the posttreatment visual outcome of large posterior pole tumors. We treated 17 patients (20 eyes) with group III-V retinoblastoma and large posterior pole tumors with external beam radiation. Visual acuity after treatment ranged from 5/200 to 20/50. Potential posttreatment visual function was difficult to predict using such pretreatment factors as age at diagnosis, funduscopic appearance, and the number, size, and location of the tumors. Surprising visual function was obtained in some patients with multiple large macular tumors. Follow up ranged from 1 to 8 years. No patient developed metastatic disease; however, four patients required subsequent cataract extraction. This study supports the consideration of radiation therapy as the primary treatment in eyes previously felt to have a poor visual outcome.

Lesions simulating retinoblastoma

Of 500 consecutive patients referred to the Ocular Oncology Service at Wills Eye Hospital with the diagnosis of possible retinoblastoma, 288 (58%) were found on clinical evaluation to have retinoblastoma and 212 (42%) had lesions that simulated retinoblastoma. A total of 23 different conditions accounted for the 212 pseudoretinoblastomas. Three most common pseudoretinoblastomas were: persistent hyperplastic primary vitreous (28%), Coats' disease (16%), and presumed ocular toxocariasis (16%). Congenital cataract and retinopathy of prematurity accounted for a much lower percent of pseudoretinoblastomas in this series as compared to a previously reported series. The pertinent clinical features that serve to differentiate these simulating lesions from retinoblastoma are reviewed.

A prospective study on the treatment of retinoblastoma in 72 patients

Seventy-two patients with retinoblastoma (RTB) (unilateral [47 patients] and bilateral [25 patients]) were studied for a period of 6 years. Treatment consisted of enucleation of those eyes that had severe involvement and was followed by radiation therapy and/or chemotherapy (systemic or intrathecal) according to clinical pathologic staging. All patients who underwent nonsurgical treatment received systemic chemotherapy. Intrathecal chemotherapy was administered when there was involvement of the central nervous system. Nonsurgical treatment consisted of radiation therapy and/or light coagulation, followed by enucleation if there was no response. The overall survival rates were 79% for unilateral disease (median follow-up time, 63 months) and 72% for bilateral disease (median follow-up time, 81 months). Vision was regained in 14 of 21 conserved eyes.

Clearance of S-(3-amino-2-hydroxypropyl) phosphorothioate (WR-77913) in rats

Complications of radiotherapy in the treatment of retinal and choroidal neoplastic diseases include cataract formation, radiation retinopathy, neovascular glaucoma, cystoid macular edema, and subretinal neovascularization. These side effects may be minimized by the use of compounds known to have a protective effect on normal ocular tissues without impeding the benefits of therapy. Phosphorothioates, first developed under the Antiradiation Drug Development Program of the U.S. Army Medical Research and Development Command, have been reported to protect normal tissues during radiation therapy in a variety of animal models. One of the phosphorothioates, WR-77913 (S-[3-amino-2-hydroxylpropyl]phosphorothioate) was found to inhibit cataract formation in rats after radiation exposure. To test the efficacy of WR-77913 in the retina, we established a high-pressure liquid chromatography method to measure the levels of dephosphorylated WR-77913 and studied the drug's clearance from the lens, retina, blood, kidney, and liver in rats.

Radiation regression patterns in treated retinoblastoma: 7 to 21 years later

A retrospective review of cases on file at the Ophthalmic Oncology Center of The New York Hospital-Cornell Medical Center, New York was performed in order to examine the appearance of radiation regression patterns 7 or more years after successful treatment of retinoblastoma with external beam radiotherapy. Forty-eight patients were found to have 89 tumors in 57 eyes which were treated solely with external beam radiation; they were followed for a minimum of 7 years and had sufficient information available for analysis. All but five of the patients had bilateral retinoblastoma. Seventy-four of the 89 tumors continued to be ophthalmoscopically visible after 7 or more years. Taking into account those that did change between the time of first evaluation (usually at the completion of treatment) and final evaluation (7 or more years after treatment), the number of Type I regressions increased by 10.1%, Type IIs decreased by 19.1%, Type IIIs fell by 7.8%, Type IVs rose by 10.1%, and the number of tumors that disappeared increased by 6.8%. Type II remained the most common regression throughout the follow-up. The regression with the greatest potential for change was the Type II regression. The pretreatment volume of the tumor correlated with long-term radiation regression patterns. The smallest tumors (mean size 1.1 dd [disc diameter] or less in size) completely disappeared, while the largest (mean 9.9 dd) became Type I regressions.

Radiotherapy of retinoblastoma. A review of 63 children treated with different irradiation techniques

This is a retrospective review of treatment results in 63 children with retinoblastoma (RB) who received therapeutic irradiation from January 1975 to June 1988. Patient ages ranged from birth to 5 years with a mean age of 12.5 months. Three treatment groups were identified. In Group A, episcleral plaque was the only irradiation modality. In this group, 24 patients and 25 eyes with tumors of Reese-Ellsworth Stages I to III, and selected Stage VB tumors were irradiated using eye plaques. Twenty-two of 25 (88%) eyes are without evidence of disease (NED), and all patients are alive. Two eyes were enucleated for recurrent RB. Two of 23 eyes developed minimal cataracts. In Group B, external-beam was the only irradiation modality. Twelve patients with 21 involved eyes comprise this group. Thirteen eyes received EBRT alone. Seventy-seven percent of 13 eyes have NED. Four eyes developed cataracts. Three of 13 eyes required enucleation for progression of disease; one of these was Stage IVA and two of them were Stage VA. For Group C, external-beam plus episcleral plaque was used. Twenty-seven patients and 51 eyes with advanced retinoblastoma were included in this group. Episcleral plaque was used in 29 eyes as a salvage procedure for recurrent RB, or in selected cases was used as a boost after initial external beam irradiation. Fifteen of 29 eyes (52%) remain with NED with useful vision, and nine developed cataracts. Enucleation was performed in 14 eyes for recurrent RB. The authors conclude that radiation therapy has a major role in the management of RB due to its ability to control even advanced disease, allowing preservation of vision in a significant number of patients.

New and recurrent tumor foci following local treatment as well as external beam radiation in eyes of patients with hereditary retinoblastoma

The study is based on a retrospective analysis of data from 200 patients with hereditary retinoblastoma. Apart from four unilateral cases with a positive family history all patients had bilateral disease; 229 appeared suitable for conservative treatment while 167 eyes had to be enucleated. Primary local treatment was performed in 102 eyes, while 127 eyes received primary external beam radiation using a linear accelerator. Follow-up was adjusted by life tables, with 75% of the patients being observed longer than 2 years. Using life-table statistics new and recurrent tumors were found in 41% of all patients and in 95% of these cases they were noted within 26 months after initiation of therapy. Among eyes treated with primary external beam radiation new and recurrent tumors were observed significantly less frequently when 50 Gy (22% compared with 49% after 40 Gy) and a highly accurate beam alignment technique (22% compared with 48% after alignment to the outer bony canthus) were applied. The incidence of recurrent tumors following primary local treatment did not differ significantly with regard to the application of either photo- or cryocoagulation (28% vs 33%), while no recurrence was observed among tumors that were suitable for primary treatment using ruthenium or cobalt plaques.

Magnetic resonance imaging in retinoblastoma and retinocytoma: a case report

Magnetic resonance imaging (MRI) is playing a growing role in the evaluation of ocular and orbital tumors. We report the case of a 26-month-old child presenting an undifferentiated retinoblastoma with a differentiated retinocytoma component in his left eye. After the eye was enucleated, we could correlate the clinicopathologic findings with the MRI scans. Both the undifferentiated retinoblastoma and the differentiated retinocytoma components could be determined on magnetic resonance imaging. Because different levels of metabolic activity within a tumor mass may influence largely T1 and T2 parameters, accurate determination of these values may be useful in determining the differentiation of a retinoblastoma, enabling a better therapeutic approach and assessment of the response to treatment.

The role of cryotherapy in the management of retinoblastoma

Between February 1974 and August 1987, we treated 67 retinoblastomas in 47 eyes of 45 patients with cryotherapy (triple freeze-thaw technique). Overall, cryotherapy eradicated 53 (79%) of the tumors, whereas additional treatment with episcleral plaque radiotherapy, external beam radiotherapy, or enucleation was necessary in 14 (21%) of the tumors. Tumor destruction was achieved with one or more cryotherapy treatments in all cases in which the tumor was no greater than 2.5 mm in diameter and 1.0 mm in thickness, and in which the tumor was confined to the sensory retina without seeding into the adjacent vitreous humor. We therefore recommend cryotherapy in such cases. Cryotherapy alone failed in 14 larger tumors, ten of which had clinical evidence of vitreous seeding by tumor cells. Cryotherapy is therefore contraindicated in cases of vitreous seeding or if the tumor exceeds 3.5 mm in diameter and 2.0 mm in thickness. Cryotherapy can be successful for tumors up to 3.5 mm in diameter and 2.0 mm in thickness, but more than one treatment may be necessary.

Decreasing frequency of enucleation in patients with retinoblastoma

We reviewed our 15-year experience with the management of 324 cases of retinoblastoma. There has been a definite trend away from enucleation in both unilateral and bilateral cases during recent years. In cases of unilateral retinoblastoma, the affected eye was salvaged in 4% of cases (two of 49) during the five-year interval from 1974 through 1978, in 14% of cases (seven of 50) from 1979 through 1983, and in 25% of cases (20 of 80) from 1984 through 1988. In cases of bilateral retinoblastoma, both affected eyes were salvaged in 4% of cases (one of 24) from 1974 through 1978, in 18% of cases (nine of 50) from 1979 through 1983, and in 25% of cases (18 of 71) from 1984 through 1988. Earlier diagnosis of retinoblastoma and refinements in conservative methods of management are believed to be the main reasons for this trend away from enucleation.

Episcleral plaque radiotherapy for retinoblastoma

The authors report their preliminary results of episcleral plaque radiotherapy (cobalt 60, iridium 192, ruthenium 106, and iodine 125 plaques) in 50 selected patients with retinoblastoma. There were 97 plaque applications to 51 affected eyes in these 50 patients. The plaque was used as primary treatment in 15 eyes and as secondary treatment after failure of external beam radiotherapy, photocoagulation, and/or cryotherapy in 36 eyes. Vitreous seeding of tumor cells was evident ophthalmoscopically in 49 of the 51 eyes, negating the possibility of ultimate success by further photocoagulation or cryotherapy. In 18 patients, the contralateral eye had been enucleated and the remaining eye was being considered for enucleation because all other treatment modalities had failed. In 2 of these 18 patients (11%), the remaining eye was salvaged with plaque radiotherapy and some vision was preserved. In 33 eyes with less advanced tumors, 31 had some degree of vitreous seeding by tumor cells. The eye has been retained in all 33 of these patients and useful vision preserved in most. On the basis of these preliminary observations, the authors conclude that plaque radiotherapy can be used successfully as a primary treatment for selected cases of unilateral or bilateral retinoblastoma or as a supplemental treatment after other treatment methods have failed. The current indications for plaque radiotherapy and its advantages over other therapeutic modalities are discussed.

External beam irradiation for retinoblastoma: patterns of failure and dose-response analysis

Eighteen children with retinoblastoma (25 eyes) were treated with external beam radiation at the Mayo Clinic between January 1977 and January 1987; 15 eyes were in groups I to III and 10 were in groups IV and V (Reese-Ellsworth classification). The median number of tumors per eye was 3. Radiation therapy consisted of 4- or 6-MV photons. Doses varied from 39 to 51 Gy in 1.8- to 3.0-Gy fractions. Fourteen eyes were treated through lateral fields by anterior segment-sparing techniques, and 11 eyes were treated by an anterior approach with no attempt at anterior segment sparing. All patients survived (median follow-up, 31.5 months). Cataracts developed in five eyes at a median of 23 months, four in eyes treated with anterior segment-sparing techniques. Of the 15 group I to III eyes, 6 required additional treatment; 4 were salvaged with cryotherapy or photocoagulation and 2 were enucleated. Of the 10 group IV and V eyes, 8 required additional treatment; 4 were salvaged with cryotherapy or photocoagulation, 1 with persistent disease is being followed closely, and 3 were enucleated. Ten (71%) of the 14 eyes treated with anterior segment-sparing techniques required additional treatment (9 of the 10 for tumors anterior to the equator). Four (36%) of the 11 eyes treated with an anterior approach required additional treatment (3 of the 4 for tumors in the posterior pole of group IV or V eyes). Ninety percent of the tumors 10 disc diameters or smaller (1 disc diameter = 1.6 mm) were controlled independently of dose and fractionation used when they were not in the low-dose area of the anterior retina of an eye treated with an anterior segment-sparing technique. We find that use of lateral, anterior segment-sparing techniques has a high risk of anterior retinal tumor development and cataract formation and should be abandoned in favor of techniques that treat the entire retina. A dose of 45 Gy in 1.8-Gy fractions appears to be adequate for local control of tumors smaller than 10 disc diameters. Larger tumors may require additional treatment.

Optic nerve involvement in retinoblastoma

This retrospective review of 814 retinoblastoma patients discloses 240 cases of tumor extension into the optic nerve. Optic nerve involvement was classified according to the degree of invasion; grade I is superficial invasion of the optic nerve head only, grade II is involvement up to and including the lamina cribrosa, grade III is involvement beyond the lamina cribrosa, and grade IV is involvement up to and including the surgical margin. The incidence of optic nerve involvement was 29.5% (240/814). The mortality rate of patients with optic nerve involvement with grade I was 10%; grade II, 29%; grade III, 42%; and grade IV, 78%. Actuarial life-table analysis shows an increased mortality rate with increasing grade of optic nerve involvement. Multivariate statistical analysis shows that the grade of optic nerve involvement and the age at diagnosis of optic nerve involvement are the factors most significantly associated with survival.

The treatment of primary intraocular malignancy

This paper will summarize much of the information derived in an association between The Department of Radiation Oncology of Hahnemann University Hospital and the Oncology Service of Wills Eye Hospital of Thomas Jefferson University, a collaborative effort for the treatment of primary intraocular malignancies that has spanned the last dozen years. In that time we have treated malignant intraocular melanoma by radioactive eyeplaque brachytherapy and have begun to develop a similar program for treatment of recurring retinoblastoma. These experiences will be described.

Embryonal rhabdomyosarcoma arising in the masseter muscle as a second malignant neoplasm

A case is reported about a patient who was originally treated for bilateral retinoblastoma and subsequently developed an embryonal rhabdomyosarcoma in the masseter. Such patients have a genetic predisposition to a second malignancy that statistically far exceeds the rate for the general population. In addition, current treatment methods also increase the patient's susceptibility to another malignancy. This case emphasizes the necessity of maintaining a high degree of clinical suspicion in the evaluation of any lesion that may appear subsequent to the treatment of cancer in children, particularly bilateral retinoblastoma.

Bilateral retinal vascular hypoplasia associated with persistence of the primary vitreous: a new clinical entity?

Three infant boys with a bilateral congenital retinopathy characterized by retinal vascular hypoplasia and persistence of the primary vitreous are described. The infants were healthy and had no non-ocular physical abnormalities. None had histories of prematurity or low birth weight. Family histories were negative to similar retinopathy, and the fundi of all examined blood relatives were normal. The described congenital retinopathy is compared and contrasted with persistent hyperplastic primary vitreous, Norrie's disease, idiopathic retinal dysplasia, familial exudative vitreoretinopathy, retinopathy of prematurity, and incontinentia pigmenti.