[The relevance of molecular biology studies in the genetic counselling of Argentine retinoblastoma families]. / Importancia de los estudios de biología molecular en el asesoramiento genético de familias argentinas con retinoblastoma.

OBJECTIVE: Evaluate the relevance of RB1 mutations detection in the genetic counselling of Argentine retinoblastoma families. METHODS: We included in this study 34 Argentine families with bilateral and unilateral Retinoblastoma (Rb). 130 DNA samples from leukocytes, tumors and chorionic villus were analyzed by indirect and direct molecular biology assays like Southern blot, segregation of polymorphisms BamHI, Rbi4, XbaI y Rb 1.20 (PCR-RFLP, PCR-STR), PCR-heteroduplex and sequencing of RB1 gene. RESULTS: Molecular biology analysis was informative in 18 out of 34 families studied (53%), 56% with bilateral and 44% with unilateral Rb. DNA tumor samples of 11 patients were available and could be studied by loss of heterozygosity (LOH) detection, that allowed us to identify the mutated RB1 allele in 9 (82%) patients. When tumor samples were not analized, the studies were informative only in 9 out of 23 patients (39%); we used direct mutation detection in 17 (41% informative) and indirect assays in 20 (60% informative) patients. CONCLUSIONS: The results prove the necessity to have DNA tumor, when the patient has been enucleated, and emphasize the importance of direct mutation detection in families with early sporadic Rb without tumor sample. The RB1 molecular biology contributed to the adequate genetic counselling of Argentine patients and relatives and their appropriate early treatment planning (Arch Soc Esp Oftalmol 2009; 84: 557-562).

Importancia de los estudios de biología molecular en el asesoramiento genético de familias argentinas con retinoblastoma / The relevance of molecular biology studies in the genetic counselling of argentine retinoblastoma families

Objetivo: Evaluar la importancia de la detección demutaciones del gen RB1 en el asesoramiento genéticode las familias argentinas con retinoblastoma.Métodos: Se incluyeron en este estudio 34 familiasargentinas con Retinoblastoma (Rb) bilateral y unilateral.Se analizaron 130 muestras de ADN de leucocitos,tumores y vellosidades coriónicas, porensayos de Biología Molecular indirectos y directos,como Southern blot, segregación de los polimorfismosBamHI, Rbi4, XbaI y Rb 1.20 (PCRRFLP,PCR-STR), PCR-heteroduplex y secuenciacióndel gen RB1.Resultados: El análisis molecular fue informativoen 18 familias de las 34 incluidas en el estudio(53%), el 56% con Rb bilateral y el 44% con Rbunilateral. Se contó con muestras de ADN tumoralde 11 pacientes que se estudiaron para detectar pérdidade heterocigosidad (LOH), que posibilitó identificarel alelo RB1 mutado en 9 pacientes (82%).Cuando no se analizaron las muestras tumorales, los estudios fueron informativos solo en 9 de los 23pacientes (39%); se utilizó la detección directa en17 pacientes (41% informativo) e indirecta en 20(60% informativo).Conclusiones: Los resultados demuestran la necesidadde contar con ADN del tumor, cuando elpaciente fue enucleado, y acentúan la importanciade la detección directa de la mutación en familiascon Rb esporádico temprano sin muestra tumoral.Los estudios de biología molecular contribuyeroncon el adecuado asesoramiento genético de pacientesargentinos y sus familiares y el diseño apropiadode su tratamiento temprano(AU)

Objective: Evaluate the relevance of RB1 mutationsdetection in the genetic counselling of Argentineretinoblastoma families.Methods: We included in this study 34 Argentinefamilies with bilateral and unilateral Retinoblastoma(Rb). 130 DNA samples from leukocytes,tumors and chorionic villus were analyzed by indirectand direct molecular biology assays like Southernblot, segregation of polymorphisms BamHI,Rbi4, XbaI y Rb 1.20 (PCR-RFLP, PCR-STR),PCR-heteroduplex and sequencing of RB1 gene.Results: Molecular biology analysis was informativein 18 out of 34 families studied (53%), 56% withbilateral and 44% with unilateral Rb. DNA tumorsamples of 11 patients were available and could bestudied by loss of heterozygosity (LOH) detection,that allowed us to identify the mutated RB1 allele in9 (82%) patients. When tumor samples were notanalized, the studies were informative only in 9 outof 23 patients (39%); we used direct mutation detection in 17 (41% informative) and indirectassays in 20 (60% informative) patients.Conclusions: The results prove the necessity tohave DNA tumor, when the patient has been enucleated,and emphasize the importance of direct mutationdetection in families with early sporadic Rbwithout tumor sample.The RB1 molecular biology contributed to the adequategenetic counselling of Argentine patients andrelatives and their appropriate early treatment planning(AU)

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.

Treatment of retinoblastoma. Results obtained from a prospective study of 51 patients.

During 4 years, 51 patients with retinoblastoma were studied (unilateral 32, and bilateral 19). Treatment consisted of enucleation of those eyes which showed massive involvement followed by radiotherapy when there was optic nerve and/or orbit involvement. Systemic chemotherapy was administered to all patients who underwent nonsurgical treatment and when the histologic examination showed choroidal optic nerve head and/or optic nerve involvement or residual tumor after enucleation. When there was compromise of the central nervous system intrathecal chemotherapy was administered. Nonsurgical treatment consisted of radiotherapy and/or light coagulation. Survival was 90.6% for unilateral cases and 84.2% for the bilateral. The median follow-up was 31 months and 29 months, respectively. Of 19 conservated eyeballs, 16 preserve useful vision (63%).

Combined therapy of human interferon (HI) and secretory immunoglobulin (S-IgA) in the treatment of human herpetic keratitis.

The topical action of a combined therapy of human interferon (3000 U/ml) and secretory immunoglobulin IgA (1,5 mg/ml) was studied in 56 patients with herpetic keratitis. The pain and photophobia disappeared within 48 h after the beginning of treatment and a marked reduction of the corneal lesion during the first week of treatment was observed in all the patients. The therapy was effective, with complete healing of the lesion in 94.8% of cases; 72.2% of them healed in less than 15 days. The highest frequency of healing was between 5 and 10 days, and the rest up to 30 days. Humoral, immunological and delayed hypersensitivity studies were carried out in 36 patients.