Officers and family members are extremely concerned for the safety and welfare of Joyce Holme, who was last seen at her Fulham home at around 8pm on Saturday, January 14.
The 80-year-old has Alzheimer's and police say she may not know her name.
Mrs Holme was last seen wearing a grey woolly jumper, black trousers and slippers.
She is Greek, is of short build and has grey hair.
Anyone with information relating to her whereabouts should contact police on 101, or you can send a message to the police via Twitter to @MetCC.
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