Do you know if this is serious or what could it be due to? Is it a symptom of a tumor?

The user asked if a depression in their skull could be a symptom of a tumor. The pharmacist responded that the risk of it being related to cancer is virtually nil. They suggested that the depression could be caused by a fusion not complete of the skull bones, leaving space for a fontanelle like in babies. They recommended increasing hydration and seeing a doctor if worried, but reassured that it is unlikely to be serious.