Retinoblastoma may occur in families. The risk of occurrence in the offspring of a patient can be roughly estimated based on the family history. A more precise estimate may be reached following genetic analysis of the patient and other family members.
Parameters:
(1) patient affected or not
(2) involvement in patient’s parents
(3) involvement in patient’s siblings
(4) involvement in any of patient's children
Patient Affected
|
Tumor Pattern in Patient |
Other Family Members Affected |
Risk in Offspring |
|
unilateral |
parent or sibling (other family member) |
45-50% |
|
unilateral, unifocal |
no other affected relatives |
2-6% |
|
unilateral, multifocal |
no other affected relatives |
6-50% |
|
bilateral |
other family member affected |
45-50% |
|
bilateral |
no other family member affected |
45-50% |
where:
• Table 17.2 in Harper lists "parent or sibling" for the first entry, but "other family member" for the other 3. For the implementation I added an affected child to be an affected family member.
Patient Unaffected
|
Tumor Pattern in Family Members |
Family Members Affected |
Risk in Offspring |
|
unilateral |
parent and sibling |
5% |
|
unilateral |
two siblings |
5% |
|
unilateral |
one affected sibling |
1% |
|
unilateral |
one affected child (offspring) |
1% |
|
bilateral |
one affected child (offspring) |
2% |
|
bilateral |
parent affected |
5% |
where:
• The risk for bilateral disease in a sibling was not listed. For the implementation I used 2-6%.
Specialty: Genetics
ICD-10: ,
