The role of radiation therapy in retinoblastoma.

Retinoblastoma is the most common eye malignancy in Southeast Asia. In the early stage of the disease, photocoagulation, cryotherapy combined with chemotherapy and radiation therapy not only preserve vision but also preserve life. In advanced cases, the patient almost always refuses treatment when they are told to have enucleation and this leads them to more severe disease with distant metastasis. Nevertheless, even in such a poor condition, this report has shown several cases with very poor prognostic factors but effective radiation, chemotherapy after surgery still provided a very good outcome. Thus, the public should be educated that this disease can be cured even in the advanced stage. Early detection for the sake of vision and quality of life is the future intent. In the near future, it is hoped that fewer patients will refuse treatment or be lost to follow-up because of their ignorance and poverty.

Radiation treatment of retinoblastoma: experience in the past two decades.

This series of 193 patients represents the results in management of retinoblastoma. In cases treated 15 years ago when definitive radiotherapy and fat soluble chemotherapy were not utilized, the results of the treatment were very disappointing. The outcome was more promising after October 1985. Even if all the patients were in the advanced stages, we had a promising outcome, so effective modality of treatment is the most important prognostic factor. The other factors that influence the prognosis include the time for initial treatment, the time for starting the postoperative radiation and the efficiency of the radiation treatment. The follow-up period of 2 years after treatment is adequate to predict the outcome.

Chemotherapy in patients with retinoblastoma.

Chemotherapy composed of vincristine, cyclophosphamide, procarbazine and intrathecal thiotepa/methotrexate (in the indicated ones) were given for 1.5 years in the doubtful and very unfavorable (Reese-Ellsworth classification) cases of retinoblastoma. There were 58 new cases treated at the Department of Ophthalmology and the Department of Pediatrics, Ramathibodi Hospital from October 1, 1985 to December 31, 1991. Eight cases had refused the surgery prior to admission. Nine cases were not given chemotherapy due to the very advanced cases and refusal. Forty-nine cases received chemotherapy. Eighteen cases were not followed. Among 31 evaluable cases, three cases had progression of the disease. Twenty-eight cases (90%) were clinically well 2 months-6 years after discontinuation of chemotherapy. The good result could be attributable to spontaneous regression (minimal percentage), surgery, radiation therapy or chemotherapy. However, obvious chemotherapeutic effects were seen in some cases. Even though 28 cases seemed to have good result including three of the 8 cases who had refused surgery before admission, we should stress that retinoblastoma is a curable disease provided that early diagnosis and treatment are rendered. Ophthalmologic examination in first degree relatives should be done in the bilaterally involved cases.

Dacryocystorhinostomy at Ramathibodi Hospital.

Two hundred and seventy patients with idiopathic obstruction of the lacrimal passage between the sac and the nasolacrimal duct, who underwent external dacryocystorhinostomy at the Department of Ophthalmology, Ramathibodi Hospital were studied retrospectively. All the patients had the operations between 1983 and 1987; 240 were female (88.9%) and 30 were male (11.1%), with, a ratio of 8 female to 1 male. The ages ranged from 3 to 83 years, with the peak in the 46-55 age group (25.19%). The overall surgical success rate was 86.5 per cent, the definition for success being a relief of the obstruction as evident symptomatically and by the ability to irrigate the saline from the puncta to the nasal cavity at follow-ups of more than 21 days postoperatively. The patients were further subdivided into the "silastic" group and the "non-silastic" group: and the success rate were 75.5 and 95.7 per cent respectively. Significant complications of the dacryocystorhinostomy were recorded in 11 cases; 2 wound infections, 2 lacrimo-cutaneous fistulae, 5 severe operative hemorrhage and 2 ethmoidal sinus involvement.

Challenge of the two neural tumors: neuroblastoma and retinoblastoma.

Fifty cases of neuroblastoma and 29 retinoblastoma patients who had additional chemotherapy were analyzed retrospectively. Male:Female ratio were 1:1 and 0.8:1, the ages ranged from birth to 14 years (4 +/- 3.42 year) for neuroblastoma, and one month to 5.5 years (2.4 +/- 1.4 year) for retinoblastoma. More than 70%-90% of them came in advanced stages. The treatment consisted of surgical resection, enucleation or exenteration if feasible. Radiation therapy and chemotherapy were given as specific and palliative measures. All of the neuroblastoma who were younger than 8 months old survived long-term. Various chemotherapeutic agents did not seem to effect the outcome of the advanced cases of these two diseases. The retinoblasts did not seem to be sensitive to MTX and Ara-C. Thio-tepa intrathecally seems to be worth trying. Since these two tumors are not sensitive to treatment and are still a great challenge to the developed countries, awareness of the diseases, early diagnosis and early treatment are appropriate approaches for the developing countries.