Can trauma cause cancer in a mole?

Sometimes : There have been reports of cancer developing in areas of prior trauma including burns or a strong bruise. However, the cancer usually develops many years later. If you have a mole and it has had trauma, bring it to the attention of a doctor who will decide if it needs a biopsy or can be watched.

No: At best we are rarely left with no other explanation but almost always, considering previous state of mole, exact location of injury and time frame to development, all usually points toward trauma, abrasion or scratching, etc as reasons that lead us to evaluate the mole - not causing cancerous degeneration. A traumatized non-cancerous mole often heals normally while cancerous moles/lesions don't.