Abstract
Purpose: :
To measure 1) the incidence of RB in relatives of patients with bilateral (BR) or unilateral (UR) RB with no family history, compared to the theoretical risk, and 2) the costs of surveillance without, and with, knowledge of the proband’s RB1 mutation.
Methods: :
Clinical and family data were collected retrospectively from the chart and database. The direct health care cost of surveillance with and without mutation knowledge was calculated.
Results: :
Diagnosis of RB in relatives confirmed the conventional risk in the absence of molecular knowledge, supporting our schedule of surveillance. Of relatives of 152 UR probands, 6/1181 developed RB (4/48 offspring, 1/201 siblings, 1/48 offspring of unaffected sibs, 0/884 first cousins). Of relatives of 103 BR probands, 31/853 developed RB (7/26 offspring, 17/159 siblings, 7/620 first cousins, 0/48 offspring of unaffected sibs). Cost of RB1 molecular testing was $4250 ($CA) for probands and $550 for subsequent at–risk relatives. Surveillance cost $4763 per newborn child. Elimination of conventional surveillance for infants proven to not carry the proband’s RB1 mutation would save $7,072 per UR family and $12,624 per BR family.
Conclusions: :
Conventional surveillance is effective for at–risk relatives if the proband’s mutation is unknown. RB1 molecular diagnosis improves quality and reduces cost of family care by reducing the number of children undergoing unnecessary surveillance.
Keywords: retinoblastoma • gene screening