الفهرس 
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Abstract
Retinoblastoma is a malignant retinal tumor; despite of its rarity among body tumors; it is the most common intraocular tumor in childhood age group seen as 1 case per 18,000-30,000 live births.
It is a slowly growing tumor and despite of that it is aggressive once metastasize,
The tumor usually arise from the inner plexiform layer giving 4 patterns of growth; endophytic when breaking the internal limiting membrane and seeds in the vitreous, exophytic when breaking the external limiting membrane and seeds in the subretinal space, diffuse infiltrating type which is diffuse flat growth. The growth pattern is mostly mixed which is the most common .
The danger of retinoblastoma seen when metastasis occur either perineural across the optic nerve to the meninges or hematogenous to bone marrow and liver, the cure rate of metastatic cases even with aggressive chemotherapy is not exceeds 5%.
Metastasis is best seen early in bone marrow aspirate and CSF analysis; while in imaging it is seen in MRI spine and brain as well as CT chest and abdomen.
Retinoblastoma is usually seen in first 2 years of life and in this age group usually being hereditary appears bilateral or unilateral multifocal as the first chromosomal injury occur intrauterine (constitutional) and the second after birth; while later on it will be related to postnatal somatic genetic mutation and is mostly unilateral.
Clinically the most common presentation is absent or abnormal red reflex (in photographs) seen as leucocoria (white pupil), or to less extent it could be presented by conjunctival redness or strabismus, rarely presented by glaucoma, orbital cellulitis, hyphemia or advanced mass in late cases.
The child should be investigated by RetCam or at least routine fundus examination under general anesthesia, if retinoblastoma was diagnosed; further extraocular assessment by MSCT and high resolution MRI should be done for the orbit and brain; the latter is for detection of choroid infiltration, extra ocular spread, perineural spread and detection of pineal or suprasellar masses known as trilateral and quadrilateral retinoblastoma. Ocular US is useful in rapid ocular detection and follow up.
Classically retinoblastoma was treated by enucleation that was usually combined with external beam radiotherapy (based on old Reese-Ellsworse classification) or the more recent systemic chemotherapy (based on recent international classification).
With advancement in medicine, local therapies were developed like intravitreal injection of chemotherapy, brachytherapy via implanted scleral plaque and local ablative therapies e.g. laser photocoagulation, thermotherapy and cryoablation, these techniques are suitable for early stages or as complementary added therapies for residual small masses after systemic chemotherapy.
Reese did the first intra-arterial injection via puncture of ICA at 1954. Kiribuchi did non selective OAC at 1968 via ICA-ECA collaterals. Recently local intra-arterial delivery of chemotherapy is the most accepted beneficial technique by gaining marked tumoricidal effect via a small amount of chemotherapy and avoidance of systemic complications.
Also OAC avoid the development of secondary orbital tumors (osteosarcoma) and brain gliosis resulting from external beam radiotherapy.
Another advantage of OAC over intravitreal injection is the avoidance of extraocular seeding via the needle track, also local ablative techniques will cause great harm in foveal lesions in contrary to ophthalmic artery chemosurgery.
Melphalan can be used alone or combined with topotecan and carboplatin in advanced cases for better response.
Ophthalmic artery chemotherapy results were evaluated after 13 years confirming that there is no death, no related neurological deficit, no vascular or sever ocular complications, no reported child death (only 1% worldwide due to development of pineal tumors while 0% from metastasis), it can be done safe for children in 2nd month of life without need to hospitalization that was related mostly to neutropenia, both eyes can be treated in the same session and called tandom therapy. It is effective in globe salvage which reached average 91.5% universally.
The procedure done under general anesthesia with transfemoral approach and ophthalmic artery cannulation then infusion of diluted chemotherapeutic dose over 30 Minutes and in the mid and after end of the infusion a test angiogram should be done to ensure patency of the ophthalmic and cerebral arteries and the child is discharged in the same or next day.
The child needs 2-4 sessions with the average number of sessions is 3, this is related to the stage of the disease; however, the number is allowed up to 6 sessions; the higher the stage, the more number of sessions are needed.
Three weeks after each session the child should be examined by RetCam to detect the response, if there is good response and still residual tumor tissue another session after 1 week will be needed, this will be continued till total resolution or maximus number of sessions that will be better to be not more than 4, if residual small tumor seen it will need local ablative therapy.
Also after each session CBC is needed to exclude toxic effect and ERG to detect retinal toxicity.
Finally after total resolution the child should be followed according to the international protocol of follow up of retinoblastoma cases.
Follow-up visits for retinoblastoma are usually scheduled:
Every 4 weeks during treatment
Every 2 to 3 months during the first year after treatment
Every 3 to 6 months until age 6 or 7
Every year after that
Eye examination is done by an ophthalmologist. This will often be done under a general anesthetic or sedation for young children.
Orbit (eye socket) exam done if the child’s eye has been removed.
MRI of the brain done to look for tumors of the pineal gland (called trilateral retinoblastoma) in children who had tumors in both eyes (called bilateral retinoblastoma).
Conclusion and recommendations :
After 4 years of our initial experience in use of OAC in treatment of children with ocular retinoblastoma we concluded that: this new line of treatment using melphalan provided a save, promising, outpatient, alternative line of treatment for cure of retinoblastoma and was helpful for us to avoid enucleation in 95% of our cases and restored vision in most of the cases. We reported only minimal transient side effects related to the procedure, there are no major complications.
Most of the treated globes by OAC needed complementary local ablative therapy to achieve complete cure of the mass.
Finally, long term follow up of the treated globes is our target to detect any possible recurrence and allow early management by either local ablation or second course of OAC. Also, we are recommended further studies with larger sample size and those using multiagent therapy for confirmation of the results and detection of long term effects.