Propagation: can this one still be rescued ?, 0 by bonitin

bonitin wrote:
I had posted this in the cacti and succulents forum, but got no replies.
Perhaps someone over here can help me with this ?:

Yesterday I met a lady who wanted my advise about a cactus she got as a gift from a dear family member. When I entered her house I noticed the poor cactus in a very dark corner of the living room. It had been there for nine months and I found it a miracle it didn't look worse than it already did.
It hadn't got one drop of water, only some spraying and was planted in a very shallow container.
I took the poor thing outside in the garden in the shadow, because the sudden shock of the full bright sun could do only more harm to it.

The problem with it is that the whole base has a brownish rotten colour with some black area's; The top still looks fine and I wondered if it could still be rescued like by cutting of the healthy upper part and replant it in special cacti-soil. What do you think ? Your advise is highly appreciated!

Here is shows the rotted base