What is an important lab study to conduct in the work-up of retinoblastoma?

In the work-up of retinoblastoma, a type of eye cancer that occurs in young children, a urinalysis can be particularly important as it helps to rule out other potential diagnoses that could present similarly with similar symptoms, such as urinary tract infections or other systemic diseases. While retinoblastoma often presents with specific signs such as strabismus or leukocoria (white reflex in the eye), conducting a urinalysis allows healthcare providers to ensure that the child does not have other underlying conditions that could confound the clinical picture. This helps in narrowing down the diagnosis to retinoblastoma and facilitates timely and appropriate management of the condition.

Other laboratory tests listed may provide useful information in different contexts, but they do not directly pertain to the investigation of retinoblastoma specifically. Therefore, the focus on a urinalysis is significant in the overall assessment and ensures a comprehensive evaluation of the patient's symptoms.