Answer: There are so many different species and cultivars of this plant (Dieffenbachia) that it is very difficult to sort them out. Also, the leaf pattern will vary depending on the growing conditions so that makes it even more difficult. You might be able to identify yours using the information in the following article. There is a table that lists and describes some of the more common named varieties.
Here are photos of a few just to give you an idea of how difficult it might be to identify any given plant. You may need to cut and paste the complete url into your browser to make it work correctly.
I hope this helps.
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