Multiplex ligation-dependent probe amplification versus fluorescent in situ hybridization for screening RB1 copy number variations in Egyptian patients with retinoblastoma.

BACKGROUND: Retinoblastoma (RB) is the most common primary intraocular malignant tumor in children. RB is mostly caused by biallelic mutations in RB1 and occurs in hereditary and non-hereditary forms according to the "two-hit" theory. RB1 mutations comprise point mutations, indels, large deletions, and duplications. Genetic testing is essential for the comprehensive treatment and management of patients with RB. AIM: The aim was to evaluate RB1 copy number variations (CNVs) using MLPA versus FISH assays in group of Egyptian patients with RB. RESULTS: 16.67% showed an RB1 deletion, abnormal methylation status, or both. CONCLUSION: Our results suggested MLPA is a fast, reliable, and powerful method and should be used as a first-line screening tool for detecting RB1 CNVs in patients with RB. Moreover, MLPA is advantageous as it evaluates the methylation status/inactivation of RB1, not possible by FISH.

Unilateral retinoblastoma; natural history and an age-based protocol in 248 patients.

OBJECTIVES: We aimed to study the clinical state and prognosis of patients with unilateral retinoblastoma who were being treated at a paediatric comprehensive cancer centre in a limited-resource country, to assess the different phases of treatment and the success of different, more complex real-life models. SUBJECTS: In this retrospective study, we created a snapshot of our retinoblastoma database for the period between 2007 and 2015. Patients whose data were included in the study were followed up until 2016. Out of a total of 744 screened patients, we included data of 248 patients who had been diagnosed with unilateral retinoblastoma. RESULTS: As classified as per the International Retinoblastoma Classification, 1 patient presented with group A, 21 with group B, 39 with group C, 104 with group D and 83 with group E retinoblastoma. Chemotherapy was the initial line of treatment in 115 patients and enucleation in 133 others. Later, 141 patients (56.9%) required further management. Patients had a mean ocular survival time of 20.8 months. Nine patients developed extraocular disease at a later stage of management: five after upfront enucleation and four after neoadjuvant chemotherapy. Mean overall survival time stood at 90.2 months. Four and three deaths were recorded in groups D and E, respectively. A single patient died in the initial chemotherapy arm, while six passed away in the initial enucleation arm. CONCLUSION: Our study highlights the importance of initial chemotherapy and close follow-up after enucleation of classes D and E affected eyes even in absence of germline mutations.

Ru106 brachytherapy for management of choroidal melanoma: do we need to adjust total dose according to the new NIST calibration measurement?

PURPOSE: To detect the need of adjusting the apical total dose according to the new NIST calibration measurement introduced by BEBIG Isotopen und Medizintechnik GmbH for the treatment of choroidal melanoma. As the total radiation dose should not be individualized depending on errors pf previous calibration but can be applicable if based on a radiosensitivity test that was able to predict the final response of tumor to radiation for each particular patient. PATIENTS AND METHODS: Twenty patients with choroidal melanomas were treated between November 2002 and July 2004 at "Suzanne Mubarak Eye Tumor Centre", National Eye centre Rod-EL Farag, Cairo, Egypt. The prescribed dose was calculated according to the new NISTcalibrated dosimetry introduced by BEBIG, but without dose modification by using a conversion factor F(type,z) from the ASMW calibrated measurement to the NIST calibrated measurement that have been calculated depending on the plaque type and the distance z from the inner concave plaque surface along the central axis. For the treatment of choroidal melanoma in this study the apical dose ranged from 9000-10400cGy with a mean of 9855 +/- 385. RESULTS: After a follow up period from 12-28 months (median of 19 months) there was a local control rate of 100 % and the three years actuarial disease specific survival was 95% as only one patient died of liver metastases. Fourteen patients had a best corrected pre-treatment visual acuity of better than 6/60 in the affected eye. At the last follow up available, useful visual acuity of>0.5 was preserved in 7 of the patients. CONCLUSION: Recalculation of the apical total dose (mostly increasing of the total dose) according to the conversion factor F(type,z), suggested by BEBIG after the new NIST calibration measurement, does not seem to have an effect on both local control and survival, in this study.