Genetic panels look at a large number of genes, many of which have no relation to the phenotype of the patient. Mutations found in these genes are known as incidental findings. The genetics community is divided as to how best to manage these incidental findings, but some guidance is available from the American College of Medical Genetics, which has identified 56 genes (Both benign and malignant) that should be reported, as there are steps the patient and their family can take to avoid morbidity and mortality (So called actionable genes).
This list of 56 genes will likely grow over time.
ACMG and ClinVar have published this list, as well as recommended actions for each gene mutation. I highly recommend you be aware of this if you are involved in genetic testing.