A Systematic Comparison of Dose Distributions Delivered in 125I Plaque Brachytherapy and Proton Radiation Therapy for Ocular Melanoma.

PURPOSE: To characterize dose distributions with 125I plaque brachytherapy compared with proton radiation therapy for ocular melanoma for relevant clinical scenarios, based on tumor base diameter (d), apical height (h), and location. METHODS AND MATERIALS: Plaque and proton treatment plans were created for 4 groups of cases: (1) REF: 39 instances of reference midsize circular-base tumor (d = 12 mm, h = 5 mm), in locations varying by retinal clock hours and distance to fovea, optic disc, and corneal limbus; (2) SUP: 25 superiorly located; (3) TEMP: 25 temporal; and (4) NAS: 25 nasally located tumors that were a fixed distance from the fovea but varying in d (6-18 mm) and h (3-11 mm). For both modalities, 111 unique scenarios were characterized in terms of the distance to points of interest, doses delivered to fovea, optic disc, optic nerve at 3 mm posterior to the disc (ON@3mm), lens, and retina. Comparative statistical evaluation was performed with the Mann-Whitney U test. RESULTS: Superior dose distributions favored plaque for sparing of (1) fovea in large (d + h ≥ 21 mm) NAS tumors; (2) ON@3mm in REF cases located ≤4 disc diameters from disc, and in NAS overall. Protons achieved superior dose sparing of (1) fovea and optic disc in REF, SUP, and TEMP; (2) ON@3mm in REF >4 disc diameters from disc, and in SUP and TEMP; and (3) the lens center overall and lens periphery in REF ≤6 mm from the corneal limbus, and in TEMP with h = 3 mm. Although protons could completely spare sections of the retina, plaque dose was more target conformal in the high-dose range (50% and 90% of prescription dose). CONCLUSIONS: Although comparison between plaque and proton therapy is not straightforward because of the disparity in dose rate, prescriptions, applicators, and delivery techniques, it is possible to identify distinctions between dose distributions, which could help inform decisions by providers and patients.

[Treatment and prognosis of primary ocular adnexal extranodal marginal zone mucosa-associated lymphoid tissue lymphoma: a report from a single center].

Objective: This study aimed to see how different initial treatment regimens affected the long-term prognosis of patients with extranodal marginal zone mucosa-associated lymphoid tissue lymphoma confining to the ocular adnexal (OAML) . Methods: Between April 2008 and April 2019, 109 patients with initial mucosa-associated lymphoid tissue confining to ocular adnexal were evaluated and followed-up, and the prognosis of various initial treatment regimens were examined. Results: A total of 36 patients underwent complete surgical resection of the lesions, and 73 patients had residual lesions after surgery, of which 37 patients chose watchful waiting, and 36 patients chose treatment. The treatment regimen included local radiotherapy and systemic treatment (chemotherapy, immunochemotherapy, the combination of radiotherapy and chemotherapy, etc.) , and no serious toxic and side effects were observed in patients receiving systemic treatment. The median follow-up time was 61 (10-142) months. The 5-year and 10-year progression-free survival (PFS) of monocular involvement patients were 78.2% and 76.0% . The 5-year and 10-year PFS rates of patients with binocular involvement were 64.4% and 23.5%. There was significant diference in PFS between patients with monocular and binocular involvement (P=0.010) . Patients who received additional treatment had higher PFS than those patients in the watchful waiting group (P=0.046) . The 5-year PFS was 71.4% and 90.1% among patients in the watchful waiting group and those who received additional treatment, whereas the 10-year PFS was 63.5% and 75.1% , respectively. Patients with OAML were still a risk of disease progression after 5 years. Conclusions: Patients with binocular involvement OAML at the start of the disease had a poor prognosis, but treatment could reduce the risk of recurrence/progression. Systemic therapy is one of the first-line treatment options for patients with OAML, who require long-term monitoring.

Treatment and prognosis of primary ocular adnexal extranodal marginal zone mucosa-associated lymphoid tissue lymphoma: a report from a single center / 中华血液学杂志

Objective: This study aimed to see how different initial treatment regimens affected the long-term prognosis of patients with extranodal marginal zone mucosa-associated lymphoid tissue lymphoma confining to the ocular adnexal (OAML) . Methods: Between April 2008 and April 2019, 109 patients with initial mucosa-associated lymphoid tissue confining to ocular adnexal were evaluated and followed-up, and the prognosis of various initial treatment regimens were examined. Results: A total of 36 patients underwent complete surgical resection of the lesions, and 73 patients had residual lesions after surgery, of which 37 patients chose watchful waiting, and 36 patients chose treatment. The treatment regimen included local radiotherapy and systemic treatment (chemotherapy, immunochemotherapy, the combination of radiotherapy and chemotherapy, etc.) , and no serious toxic and side effects were observed in patients receiving systemic treatment. The median follow-up time was 61 (10-142) months. The 5-year and 10-year progression-free survival (PFS) of monocular involvement patients were 78.2% and 76.0% . The 5-year and 10-year PFS rates of patients with binocular involvement were 64.4% and 23.5%. There was significant diference in PFS between patients with monocular and binocular involvement (P=0.010) . Patients who received additional treatment had higher PFS than those patients in the watchful waiting group (P=0.046) . The 5-year PFS was 71.4% and 90.1% among patients in the watchful waiting group and those who received additional treatment, whereas the 10-year PFS was 63.5% and 75.1% , respectively. Patients with OAML were still a risk of disease progression after 5 years. Conclusions: Patients with binocular involvement OAML at the start of the disease had a poor prognosis, but treatment could reduce the risk of recurrence/progression. Systemic therapy is one of the first-line treatment options for patients with OAML, who require long-term monitoring.

Advanced Collapsed cone Engine dose calculations in tissue media for COMS eye plaques loaded with I-125 seeds.

PURPOSE: To investigate the dose calculation accuracy of the Advanced Collapsed cone Engine (ACE) algorithm for ocular brachytherapy using a COMS plaque loaded with I-125 seeds for two heterogeneous patient tissue scenarios. METHODS: The Oncura model 6711 I-125 seed and 16 mm COMS plaque were added to a research version (v4.6) of the Oncentra® Brachy (OcB) treatment planning system (TPS) for dose calculations using ACE. Treatment plans were created for two heterogeneous cases: (a) a voxelized eye phantom comprising realistic eye materials and densities and (b) a patient CT dataset with variable densities throughout the dataset. ACE dose calculations were performed using a high accuracy mode, high-resolution calculation grid matching the imported CT datasets (0.5 × 0.5 × 0.5 mm3 ), and a user-defined CT calibration curve. The accuracy of ACE was evaluated by replicating the plan geometries and comparing to Monte Carlo (MC) calculated doses obtained using MCNP6. The effects of the heterogeneous patient tissues on the dose distributions were also evaluated by performing the ACE and MCNP6 calculations for the same scenarios but setting all tissues and air to water. RESULTS: Average local percent dose differences between ACE and MC within contoured structures and at points of interest for both scenarios ranged from 1.2% to 20.9%, and along the plaque central axis (CAX) from 0.7% to 7.8%. The largest differences occurred in the plaque penumbra (up to 17%), and at contoured structure interfaces (up to 20%). Other regions in the eye agreed more closely, within the uncertainties of ACE dose calculations (~5%). Compared to that, dose differences between water-based and fully heterogeneous tissue simulations were up to 27%. CONCLUSIONS: Overall, ACE dosimetry agreed well with MC in the tumor volume and along the plaque CAX for the two heterogeneous tissue scenarios, indicating that ACE could potentially be used for clinical ocular brachytherapy dosimetry. In general, ACE data matched the fully heterogeneous MC data more closely than water-based data, even in regions where the ACE accuracy was relatively low. However, depending on the plaque position, doses to critical structures near the plaque penumbra or at tissue interfaces were less accurate, indicating that improvements may be necessary. More extensive knowledge of eye tissue compositions is still required.

Initial evaluation of Advanced Collapsed cone Engine dose calculations in water medium for I-125 seeds and COMS eye plaques.

PURPOSE: To investigate the dose calculation accuracy in water medium of the Advanced Collapsed cone Engine (ACE) for three sizes of COMS eye plaques loaded with low-energy I-125 seeds. METHODS: A model of the Oncura 6711 I-125 seed was created for use with ACE in Oncentra® Brachy (OcB) using primary-scatter separated (PSS) point dose kernel and Task Group (TG) 43 datasets. COMS eye plaque models of diameters 12, 16, and 20 mm were introduced into the OcB applicator library based on 3D CAD drawings of the plaques and Silastic inserts. To perform TG-186 level 1 commissioning, treatment plans were created in OcB for a single source in water and for each COMS plaque in water for two scenarios: with only one centrally loaded seed, or with all seed positions loaded. ACE dose calculations were performed in high accuracy mode with a 0.5 × 0.5 × 0.5 mm3 calculation grid. The resulting dose data were evaluated against Monte Carlo (MC) calculated doses obtained with MCNP6, using both local and global percent differences. RESULTS: ACE doses around the source for the single seed in water agreed with MC doses on average within < 5% inside a 6 × 6 × 6 cm3 region, and within < 1.5% inside a 2 × 2 × 2 cm3 region. The PSS data were generated at a higher resolution within 2 cm from the source, resulting in this improved agreement closer to the source due to fewer approximations in the ACE dose calculation. Average differences in both investigated plaque loading patterns in front of the plaques and on the plaque central axes were ≤ 2.5%, though larger differences (up to 12%) were found near the plaque lip. CONCLUSIONS: Overall, good agreement was found between ACE and MC dose calculations for a single I-125 seed and in front of the COMS plaques in water. More complex scenarios need to be investigated to determine how well ACE handles heterogeneous patient materials.

Retrospective comparison of the effectiveness of various treatment modalities of extragastric MALT lymphoma: a single-center analysis.

We have performed a retrospective analysis of all patients with extragastric mucosa-associated lymphoid tissue (MALT) lymphoma treated at our institution to compare the efficacy of first-line therapeutic modalities including surgery, radiation, systemic therapy, and antibiotics. One hundred eighty-five patients with extragastric MALT lymphoma with a median age of 63 (interquartile range (IQR) 50-74) years and a median follow-up time of 49 (IQR 18-103) months were retrospectively analyzed. Time to progression and time to next therapy were used as surrogate endpoints for efficacy. Patients having either surgery (100 %), chemo/immunotherapy (85.5 %), or radiation (80 %) had significantly (p = 0.01) higher response rates than patients treated with antibiotics (33.3 %). Patients who were irradiated had significantly more progressive disease, but also the longest follow-up time. Stage, elevated LDH, anemia, elevated beta-2 microglobulin, plasmacytic differentiation, monoclonal gammopathy, or autoimmune disease did not influence the rate of disease progression nor did complete remission or partial remission from initial therapy influence time to and rate of progression. There was no significant difference in the median time to progression (p = 0.141), but the estimated time to progression (p = 0.023) as well as the estimated time to next therapy (p = 0.021) was significantly different among the various cohorts favoring surgery, chemo/immunotherapy, and radiation. Our results suggest extragastric MALT lymphoma as a potential systemic disease irrespective of initial stage. Radiation, surgery, and chemo/immunotherapy seem to be equally effective in achieving remissions and prolonged progression free survivals, but a curative potential is questionable. Localized MALT lymphomas affecting the thyroid gland or the lungs have excellent long-term progression-free survivals with surgical treatment only.

Episcleral brachytherapy for uveal melanoma: analysis of 136 cases.

PURPOSE: To assess the results of I-125 episcleral brachytherapy (EB) in uveal melanoma: tumour control, visual acuity (VA), eye preservation and survival. PATIENTS: Prospective and consecutive study of patients with a diagnosis of uveal melanoma at the Ocular Oncology Unit in the Valladolid University Teaching Hospital treated with EB between September 1997 and June 2008. Ocular examination and extraocular and systemic extension data were registered in a database at the time of the diagnosis and during the follow-up. RESULTS: Among a total of 310 patients diagnosed between September 1997 and June 2008, 136 were treated with EB (mean age, 58.3). Mean follow-up was 55.3 months. As for tumour type, 66.9% were nodular and 39% mushroom shaped. With respect to size, 80.9% were medium, 7.4% small and 11.8% large. After 4.6 years of follow-up, tumours were controlled in 97.1%, with a 55.1% reduction in mean height; only 2.9% of patients showed recurrence. VA was maintained in 16.2% of patients and 17.6% showed an increase; 33% had retinopathy and 14.6% optic neuropathy. Only 5.1% of patients underwent enucleation due to complications and there has been 1 melanoma-related death to date. CONCLUSIONS: I-125 EB is effective in tumour control, allowing preservation of the eye and useful visual function for the majority of patients.

Current treatments for radiation retinopathy.

BACKGROUND: to review the currently available therapeutic modalities for radiation retinopathy (RR), including newer investigational interventions directed towards specific aspects of the pathophysiology of this refractory complication. METHODS: a review of the literature encompassing the pathogenesis of RR and the current therapeutic modalities available was performed. RESULTS: RR is a chronic and progressive condition that results from exposure to any source of radiation. It might be secondary to radiation treatment of intraocular tumors such as choroidal melanomas, retinoblastomas, and choroidal metastasis, or from unavoidable exposure to excessive radiation from the treatment of extraocular tumors like cephalic, nasopharyngeal, orbital, and paranasal malignancies. After the results of the Collaborative Ocular Melanoma Study, most of the choroidal melanomas are being treated with plaque brachytherapy increasing by that the incidence of this radiation complication. RR has been reported to occur in as many as 60% of eyes treated with plaque radiation, with higher rates associated with larger tumors. Initially, the condition manifests as a radiation vasculopathy clinically seen as microaneurysms and telangiectases, with posterior development of retinal hard exudates and hemorrhages, macular edema, neovascularization and tractional retinal detachment. Regrettably, the management of these eyes remains limited. Photodynamic therapy, laser photocoagulation, oral pentoxyphylline and hyperbaric oxygen have been attempted as treatment modalities with inconclusive results. Intravitreal injections of anti-vascular endothelial growth factor such as bevacizumab, ranibizumab and pegaptanib sodium have been recently used, also with variable results. DISCUSSION: RR is a common vision threatening complication following radiation therapy. The available therapeutic options are limited and show unsatisfactory results. Further large investigative studies are required for developing better therapeutic as well as preventive treatment strategies.

Clinical review: treatment of vitreoretinal lymphoma.

Vitreoretinal lymphoma is the most common type of intraocular lymphoma. It is mostly a high-grade B-cell malignancy with a poor prognosis, and is often associated with primary central nervous system lymphoma. Since intraocular lymphoma was first recognized almost 60 years ago, its treatment has gradually evolved. In the early years enucleation was often performed. Since that time, radiation therapy alone, systemic chemotherapy alone, or a combination of the two have been used extensively Because of the limited intraocular penetration of drugs administered systemically, the systemic and local toxicity of chemotherapy and radiation therapy and the high rate of recurrence, intravitreous chemotherapy, mainly using methotrexate, has become popular in the last decade, with encouraging results. More recently, biological treatment with intravitreal injections of rituximab has been investigated, with good results and minimal side effects. This review summarizes the present knowledge on vitreoretinal lymphoma therapy, with an eye to future molecular approaches.

The clinical characteristics and treatment results of ocular adnexal lymphoma.

PURPOSE: To assess the clinical pattern, the histopathological findings, the response to treatments, the recurrence pattern and the prognosis of malignant lymphoma in the ocular adnexa. METHODS: This study was performed on 22 total eyes from 17 patients who were diagnosed with ocular adnexal malignant lymphoma. We retrospectively analyzed the medical records for patient information including the histological classification based on age, the gender of each patient, the symptoms and signs at the initial diagnosis, the presence of binocular invasion, the findings of the surgical biopsy, the clinical stage of each patient's tumor, and the treatment methods used and their effectiveness. The mean follow-up period was 24.8 months. RESULTS: The mean age of patients studied was 46.8 years old. Six females and 11 males were included in the study. Fifteen cases consisting of 20 total eyes represented extranodal marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT). Five of seven patients (71.4%) whose lymphoma occurred within the conjunctiva relapsed after irradiation or chemotherapy, and four of the relapsed patients were salvaged with further therapy. CONCLUSIONS: Extranodal marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT) constituted 88.2% of all lymphomas involving the ocular adnexa. Lymphoma in the ocular adnexa responded well to conventional treatment, but the recurrence rate of lymphoma in the conjunctiva was significantly high.

[The organ-saving treatment of intraocular tumors (development trends)]. / Organosokhrannoe lechenie vnutriglaznykh opukholei (tendentsii razvitiia).

A trend towards an increase of malignant tumors observed during the recent 30-40 years, an unsatisfactory efficiency of enucleation as of a method applicable to treating such tumors and the designing of a modern technical basis stimulated a new trend in ophthalmooncology, i.e. organ-saving treatment. Outlined in the paper is an analysis of achievements of modern radiation treatment techniques and of local surgical extraction of tumors suggested both by Russian and foreign researchers; the methods are shown to be promising for future development.

Gamma radiation and MC540 photosensitization of melanoma in the hamster's eye.

The purpose of this study was to evaluate the effects of cobalt-60 gamma-radiation and argon laser irradiation using injected merocyanine (MC540) as a photosensitizer on pigmented and non-pigmented Bomirski hamster melanomas growing in the eye. The animals were treated with one of four regimens, receiving gamma-irradiation only, photosensitization only, a combination of gamma-irradiation and photosensitization, or a combined time-fractionated treatment. Tumours were exposed to laser light 24 h after injection, when the photosensitizing dye concentration was highest. The degree of tissue damage was evaluated by observation of the area for necrosis, interruption of blood circulation, and the shape and dissemination of the tumour cells. Additionally, tumour growth was monitored through the measurement of tumour volume and also calculated from histological cross sections on the assumption that the tumour morphology is hemi-ellipsoidal. A single treatment of tumours by a combination of photodynamic therapy and ionizing radiation resulted in an additive effect, inhibiting tumour growth for 2-4 days. A time-fractionated treatment, given four times every 24 h, markedly delayed tumour growth for up to 6 weeks. The results indicate that MC540-mediated photodynamic treatment in combination with gamma-radiation exerts a significant therapeutic effect on a rapidly growing melanoma.

External beam radiation for retinoblastoma: results, patterns of failure, and a proposal for treatment guidelines.

PURPOSE: To analyze treatment results and patterns of failure following external beam radiation for retinoblastoma and propose treatment guidelines according to specific clinical variables. METHODS AND MATERIALS: We analyzed 27 patients (34 eyes) with retinoblastoma who received external beam radiation as initial treatment at Hahnemann University Hospital from October 1980 to December 1991 and have been followed for at least 1 year. Of the 34 eyes, 14 were Groups I-II (Reese-Ellsworth classification), 7 were Group III, and 13 were Groups IV-V. Doses ranged from 34.5-49.5 Gy (mean 44.3 Gy, median 45 Gy) in 1.5-2.0 Gy fractions generally delivered through anterior and lateral wedged pair fields. RESULTS: At a mean follow up of 35.2 months (range 12-93 months), local tumor control was obtained in 44% (15 out of 34) of eyes with external beam radiation alone. Salvage therapy (plaque brachytherapy, cryotherapy, and/or photocoagulation) controlled an additional 10 eyes (29.5%), so that overall ocular survival has been 73.5%. Local tumor control with external beam radiotherapy alone was obtained in 78.5% (11 out of 14) of eyes in Groups I-II, but in only 20% (4 out of 20) of eyes in Groups III-V. A total of 67 existing tumors were identified prior to treatment in the 34 treated eyes and local control with external beam radiation alone was obtained in 87% (46 out of 53) of tumors measuring 15 mm or less and in 50% (7 out of 14) of tumors measuring more than 15 mm. When analyzing patterns of failure in the 19 eyes that relapsed, a total of 28 failure sites were identified and consisted of progression of vitreous seeds in seven instances (25% of failure sites) recurrences from previously existing tumors in 10 instances (36% of failure sites) and development of new tumors in previously uninvolved retina in 11 instances (39% of failure sites). CONCLUSIONS: 1) We find that external beam radiation to a dose of 45 Gy in fractions of 1.5 to 2.0 Gy provides adequate tumor control in retinoblastoma eyes Groups I-II (Reese-Ellsworth classification) or tumors measuring 15 mm in diameter or less. Eyes in more advanced group staging or containing tumors larger than the 15 mm seem to require higher radiation doses. We propose treatment guidelines for external beam radiation of retinoblastoma that specifically take into account the important clinical variables of tumor stage and patient age. 2) External beam radiation does not prevent the appearance of new tumors in clinically uninvolved retina. Therefore, the traditional belief that external beam radiation can treat the retina "prophylactically" should be seriously questioned. Due to this finding and their significant less morbidity, focal treatment modalities (plaque brachytherapy, photocoagulation, and/or cryotherapy), when clinically feasible, should be considered the treatment of choice for intraocular retinoblastoma. External beam radiation should be considered only when focal treatment modalities are not clinically indicated.

Conservative treatment of retinoblastoma. The use of plaque brachytherapy.

Retinoblastoma is the most common intraocular malignancy in childhood. The tumor arises from multipotential retinal cells. Treatment options include enucleation, external beam radiotherapy, episcleral plaque radiotherapy, photocoagulation, cryotherapy or a combination of these modalities. In retinoblastoma 10% have a positive family history and of the remaining 90%, 35% represent germinal chromosomal mutations while 65% represent somatic chromosomal mutations. Therefore, approximately 40% of all retinoblastomas are hereditary and are transmitted as a highly penetrant autosomal dominant trait. In the Wills Eye/Hahnemann University experience an analysis of 400 consecutive patients, 103 tumors in 103 eyes were treated with solitary plaque radiotherapy. Tumor regression was observed in all patients initially. After 40 months mean follow-up, persistent regression was observed in 89 cases (87%) and recurrences in 13 cases (13%). Of the 13 recurrences, five were in the group treated primarily (5/31) and eight in the group treated after failing other modalities (8/72). Plaque brachytherapy is an important tool in the management of retinoblastoma. Our preliminary data suggest that plaque brachytherapy is an effective treatment modality for primary treatment as well as after failure using other modalities.

[Treatment of retinoblastoma using accelerated protons]. / Le traitement du rétinoblastome par protons accélérés.

Thanks to the Bragg vertical and the straight course of protons, the physical selectivity of proton beam is greater then that of megavoltage photons. Since January 1991 we treated 3 retinoblastomas with proton beam at the cyclotron of Louvain-la-Neuve. Results are encouraging. The short term outcome seems comparable to phototherapy, but the long term expectancy is better, because of reduced secondary malignancies. Proton beam treatment for selected retinoblastomas seems a good alternative to external radiotherapy.

Combined localized current field hyperthermia and irradiation for intraocular tumors.

Ten patients with large melanomas and one patient with recurrent retinoblastoma were treated with combined localized current field (LCF) hyperthermia and iodine 125 irradiation delivered by episcleral plaque. Tumors were heated to 43 degrees to 45 degrees C for 28 to 45 minutes. Localized current field hyperthermia when combined with irradiation appeared to induce rapid tumor necrosis. One eye enucleated 17 hours after treatment showed only focal necrosis of the melanoma, while another eye demonstrated extensive necrosis 60 hours after treatment. In all remaining eyes, tumor regression occurred within the first month of treatment. Complications included cataract formation in six eyes, hemorrhagic retinal detachment in five eyes, and phthisis in two eyes. Complications from combined therapy of large intraocular tumors in this series appeared to result from the rapid necrosis of the tumor and secondary intraocular inflammation. Intraocular temperature dosimetry measurements demonstrated a temperature gradient of not more than -0.23 degrees C/mm-1 per axial millimeter from the episcleral plaque surface to the apex of the tumor. The authors believe that LCF hyperthermia could be a suitable means of application of hyperthermia in patients with intraocular tumors if further modifications were performed to reduce ocular complications.

Xenon arch photocoagulator used for transpupillary hyperthermia.

The technique of near-infrared irradiation to obtain tumour necrosis in experimental pigmented melanomas is described. The xenon arch photocoagulator was modified and adapted for hyperthermia treatment. The adaptations included: filtering the light and changing the electronics, the aiming beam and the diameter of the beam.