Microvascular Features of Treated Retinoblastoma Tumors in Children Assessed Using OCTA.

BACKGROUND AND OBJECTIVE: To describe the microvascular features of treated, clinically regressed, or reactivated retinoblastoma lesions using an investigational portable optical coherence tomography angiography (OCTA) system. PATIENTS AND METHODS: Single-center, prospective, cross-sectional, consecutive case-series of children with previously treated retinoblastoma who underwent portable OCTA of posterior retinoblastoma lesions. RESULTS: Eight tumors from seven eyes of five children with retinoblastoma were included. Tumors with types 1 (calcified remnant, n = 3), 2 (non-calcified remnant, n = 1), and 3 (both calcified and noncalcified remnants, n = 1) regression revealed persistent intrinsic superficial vasculature on OCTA (five of five lesions; 100%). Lesions with type 4 regression (atrophic scar, n = 2) had complete vascular flow voids in the involved retina and underlying choriocapillaris. A reactivated tumor (n = 1) showed a distinct area of vascularity with prominent feeder/draining vessels. CONCLUSIONS: OCTA revealed that significant vascularity exists in inactive retinoblastoma lesions. Dilated feeder vessels may suggest continued disease activity. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:43-49.].

Local and systemic toxicity of intravitreal melphalan for vitreous seeding in retinoblastoma: a preclinical and clinical study.

PURPOSE: Intravitreal melphalan is emerging as an effective treatment for refractory vitreous seeds in retinoblastoma, but there is limited understanding regarding its toxicity. This study evaluates the retinal and systemic toxicity of intravitreal melphalan in retinoblastoma patients, with preclinical validation in a rabbit model. DESIGN: Clinical and preclinical, prospective, cohort study. PARTICIPANTS: In the clinical study, 16 patient eyes received 107 intravitreal injections of 30 µg melphalan given weekly, a median of 6.5 times (range, 5-8). In the animal study, 12 New Zealand/Dutch Belt pigmented rabbits were given 3 weekly injections of 15 µg of intravitreal melphalan or vehicle to the right eye. METHODS: Electroretinogram (ERG) responses were recorded in both humans and rabbits. For the clinical study, ERG responses were recorded at baseline, immediately before each injection, and at each follow-up visit; 82 of these studies were deemed evaluable. Median follow-up time was 5.2 months (range, 1-11). Complete blood counts (CBCs) were obtained on the day of injection at 46 patient visits. In the animal study, ERG responses were obtained along with fluorescein angiography, CBCs, and melphalan plasma concentration. After humane killing, the histopathology of the eyes was evaluated. MAIN OUTCOME MEASURES: For the clinical study, we measured peak-to-peak ERG amplitudes in response to 30-Hz photopic flicker stimulation with comparisons between ERG studies before and after intravitreal melphalan. For the animal study, we collected ERG parameters before and after intravitreal melphalan injections with histopathologic findings. RESULTS: By linear regression analysis, over the course of weekly intravitreal injections in retinoblastoma patients, for every additional injection, the ERG amplitude decreased by approximately 5.8 µV. The ERG remained stable once the treatment course was completed. In retinoblastoma patients, there were no grade 3 or 4 hematologic events. One week after the second injection in rabbits, the a- and b-wave amplitude declined significantly in the melphalan treated eyes compared with vehicle-treated eyes (P<0.05). Histopathology revealed severely atrophic retina. CONCLUSIONS: Weekly injections of 30 µg of melphalan can result in a decreased ERG response, which is indicative of retinal toxicity. These findings are confirmed at an equivalent dose in rabbit eyes by ERG measurements and by histopathologic evidence of severe retinal damage. Systemic toxicity with intravitreal melphalan at these doses in humans or rabbits was not detected.

A 10-year experience of outcome in chemotherapy-treated hereditary retinoblastoma.

PURPOSE: The aim is to report the 10-year retrospective experience of systemic chemotherapy for a population-based group of patients with hereditary retinoblastoma at a national referral centre. The outcomes include control rates, treatment side-effects, adjuvant therapy, failure rate, survival, secondary cancers and visual acuity. METHODS: All patients (n = 24, 46 eyes) diagnosed with retinoblastoma and treated with systemic chemotherapy at a national referral centre during 2001-2011 were included. Data were extracted from medical records. RESULTS: The patients were followed for a mean of 60 months (range 13-144). Four-six cycles of VEC was administered to all newly diagnosed group B/C/D/E eyes with bilateral disease and 83% (38 of 46) responded to the treatment. None of the patients discontinued chemotherapy because of adverse reactions. Altogether 26% (12 of 46) of the eyes received second-line therapy (other than thermotherapy, cryotherapy and chemotherapy). The failure rate was 35% (16 of 46) and mortality rate 0%. None of the patients developed CNS manifestations (metastases or trilateral retinoblastoma). One of the patients developed a second primary tumour (osteosarcoma) 4 years following retinoblastoma diagnosis. Altogether 17% (4 of 24) patients received radiation therapy, 28% (13 of 46) of the eyes had to be enucleated, and one patient underwent bilateral enucleation. The age-correlated visual acuity was mean of 73% of expected visual acuity. CONCLUSION: Group A/B retinoblastomas have a distinct chemotherapy response, while group C/D/E tumours do not respond as well. The success rate was 65%; while patients have a good prognosis for life, approximately one-third of all hereditary cases received radiation therapy or underwent enucleation.

Ocular manipulation reduces both ipsilateral and contralateral electroretinograms.

PURPOSE: To determine the electroretinogram (ERG) changes in eyes manipulated in the course of local ablative therapy (transpupil thermotherapy (TTT), cryotherapy or both) or scleral depression and in un-manipulated fellow, healthy eyes. METHODS: This prospective observational report summarizes 73 ERG studies in 42 patients with retinoblastoma; a study consisted of ERGs of one or both eyes (if present) followed by ocular manipulation (scleral depression, cryotherapy, transpupillary thermotherapy, pressure applied to orbital implant in an anophthalmic socket, or a 5- or 10-min delay without mechanical manipulation) followed by a repeat of the ERGs. Each patient was studied with only a single manipulation modality on any given date: 23 patients were studied only once, and 19 patients were included in more than one study occasion. RESULTS: Following local ablative treatment of patients with unilateral retinoblastoma, the photopic response decreased significantly in both the treated eye and the untouched fellow, healthy eye. Following scleral depression of the diseased eye, the photopic response immediately decreased in the diseased eye by a mean of 16 µV (21 %, p = .006) and, in the fellow, healthy eye by 40 µV (23 %, p = .0005). Following scleral depression of the fellow, healthy eye, the photopic response immediately decreased by a mean of 11 µV (4 %, p = .37) in the fellow, healthy eye, and by 16 µV (28 %, p = .01) in the diseased eye. CONCLUSIONS: Following physical ocular manipulation, the amplitude of the photopic response decreased in the manipulated, but also the untouched healthy, fellow eyes. These findings may account for some of the variation in clinical ERG recordings, particularly that observed following ocular manipulation by TTT, laser or even scleral depression.

Eye-preserving therapy in retinoblastoma: prolonged primary chemotherapy alone or combined with local therapy.

PURPOSE: To evaluate the efficacy of primary chemotherapy combined with local therapy in the treatment of retinoblastomas not treatable with a single therapeutic method. METHODS: We performed a retrospective chart review of 227 patients diagnosed with retinoblastoma. Sixty-five eyes in 52 patients had tumors not treatable with a single therapeutic method and received primary chemotherapy combined with local therapy as needed. RESULTS: Tumor control and eye salvage was achieved in 34 of the 65 eyes; the probability of ocular survival was 46.56% using the Kaplan-Meier method. Forty-three of the 65 eyes were group D or E tumors, in which tumor control and eye salvage was achieved in 16 eyes. Twenty eyes were treated with chemotherapy only, while 28 eyes received one additional modality of local therapy, and 17 eyes received two modalities of local therapy. Of the eyes treated with chemotherapy only, tumor control was achieved in 5 eyes. CONCLUSIONS: Primary chemotherapy combined with local therapy can be effective and safe in the treatment of retinoblastomas otherwise untreatable with other therapeutic methods, such as group D and E retinoblastomas. More vigorous treatment with more local therapeutic methods combined may yield even better results.

Induction of apoptosis by carboplatin and hyperthermia alone or combined in WERI human retinoblastoma cells.

This paper investigated the induction of apoptosis and perturbation of cell cycle progression caused by carboplatin (CPt) and hyperthermia alone or combined in WERI human retinoblastoma cells in vitro. An incubation of the cells with 25 or 50 microm of CPt at 37 degrees C caused apoptosis, which progressively increased during the 24-72 h treatment. Hyperthermia at 42.5 degrees C for 1 h induced apoptosis, which became significant from 24 h after the heating. Heating the cells in the presence of CPt and subsequent incubation with CPt was far more effective than treating the cells with hyperthermia or CPt treatment alone in inducing apoptosis in the WERI cells, indicating that the combination of these two modalities is potentially useful for the treatment of retinoblastoma. It appeared that the apoptosis in WERI cells caused by hyperthermia and CPt occurs during G1 phase. An interesting observation was that caspase 9 activation preceded the release of cytochrome C from mitochondria during apoptosis in WERI cells, contrary to the general notion that caspase 9 is activated by cytochrome C.

Functional results after treatment of retinoblastoma.

PURPOSE: Because of the long-term complications associated with external beam radiation in retinoblastoma, alternative treatment methods have been investigated. We conducted a retrospective study to evaluate the functional results of new treatment modalities. METHODS: Thirty-seven eyes were treated without external beam irradiation in 31 patients. The median diameter of the largest tumor in each eye was 6 mm. Primary chemotherapy was used in 25 cases, chemothermotherapy was used in 32 cases, cryotherapy was used in 28 cases, iodine 125 Plaques were used in 15 cases, diode laser thermotherapy was used alone in 11 cases, and photocoagulation was performed in 5 cases. The median follow-up after diagnosis of retinoblastoma was 41 months. The visual results were evaluated at a median age of 54 months. RESULTS: The median visual acuity of the treated eyes was 20/33. Twenty-four eyes presented a visual acuity better than 20/40, 4 eyes had a visual acuity between 20/200 and 20/40, and 9 eyes had a visual acuity less than 20/200. Maculopathy was observed in 16 cases, associated with papillopathy in 1 case. A cataract was observed in 1 case and a vitreous hemorrhage was observed in another case. Twenty-one eyes did not develop any complications. No corneal dryness and very few lens changes were observed. CONCLUSION: The functional results after local treatments for retinoblastoma are very good. The most frequent complication is maculopathy, particularly when the tumor involves or is situated close to the macula.

Chemoreduction in the initial management of intraocular retinoblastoma.

BACKGROUND: Chemoreduction is a method of reducing tumor volume to allow for more focused, less damaging therapeutic measures. OBJECTIVE: To determine whether chemoreduction could be used to decrease the size of retinoblastoma so that enucleation or external beam radiotherapy could be avoided and more conservative modalities employed. METHODS: A prospective pilot study was performed to assess the effectiveness of a 2-month chemoreduction regimen of vincristine sulfate, etoposide, and carboplatin in patients with retinoblastoma. The study included 20 patients with 54 tumors in 31 eyes. RESULTS: At the initial examination, the mean tumor base was 12 mm and the thickness, 7 mm. Vitreous seeds were present in 14 eyes (45%). A secondary retinal detachment was present in 24 eyes (77%) and, when present, involved a mean of 71% of the retina. In 11 eyes (36%) the retina was totally detached with serous subretinal fluid. After 2 months of chemoreduction, all 54 tumors showed regression in size, and 48 (89%) showed evidence of calcification. The mean tumor base was 8 mm and the thickness, 4 mm. Overall, there was a mean 35% decrease in base and 49% decrease in thickness of the tumor at the end of the treatment period. A complete response was found in 25 tumors (46%) and a partial response in 29 (54%). The subretinal fluid had resolved completely in 50% of the cases (12/24 eyes), and, in the 11 eyes with total retinal detachment, the subretinal fluid had completely resolved, leaving flat retina, in 6 eyes (54%). The vitreous seeds demonstrated some degree of regression in all cases, and in 5 eyes there was 90% to 100% calcification of the seeds. Short-term systemic toxic effects were mild (transient bone marrow suppression). Enucleation was avoided in all cases; external beam radiotherapy was necessary in 9 eyes because of diffuse vitreous seeds. The remaining 22 eyes were treated with local methods after chemoreduction. CONCLUSION: Tumor shrinkage with chemoreduction may allow treatment with less invasive measures, such as cryotherapy, laser photocoagulation, thermotherapy, or plaque radiotherapy, thereby avoiding enucleation and external beam radiotherapy.

Visual function after laser hyperthermia and chemotherapy for macular retinoblastoma.

PURPOSE: To determine whether treatment of macular retinoblastoma with chemotherapy and laser hyperthermia can lead to satisfactory visual acuity. METHODS: A child with unilateral macular retinoblastoma was treated with chemotherapy and laser hyperthermia. Visual function was assessed one year after treatment. RESULTS: At age 25 months, the patient had normal visual behavior and a normal spatial-sweep visual-evoked potential. CONCLUSION: Treatment of macular retinoblastoma with chemotherapy and laser hyperthermia may enable recovery of satisfactory visual acuity.