Can an online dermatologist determine if a skin growth is cancerous?
If you have skin lesions that fit the ABCDE criteria, in that they are Asymmetric with jagged Borders, multiple Colors, a Diameter larger than a pencil, and have been Evolving (you have observed them change over time) -- then you will likely need a biopsy to test for melanoma.
The ABCDE algorithm is just one of many tests a trained dermatologist uses in assessing risk of skin lesions, if you are unsure about whether your lesion merits a biopsy an online dermatologist can quickly examine your skin and either exclude the possibility of it being malignant or tell you that you have sufficient risk factors to merit going in person for testing.