Concise answer
A mole should be examined when it is new or changing in size, shape or colour, looks different from others, bleeds, ulcerates, itches persistently or does not heal.
A photograph can help document change but cannot reliably determine whether a lesion is harmless.
Home acids, cutting or cosmetic removal can destroy useful diagnostic features and delay appropriate care.
When evaluation may help
Arrange prompt in-person assessment for a changing or symptomatic lesion, especially with a personal or family history of skin cancer.