Displaying numeric output without changing format

I have created a Column Tree that holds numeric values, as opposed to character text. My problem is that I lose numeric formatting with commas as thousand separators, but I can see the decimal point. This is because the formatting is maintained only in output with the "write" statement, but when I pass the numeric value to the tree node, it does not hold commas for formatting.

I am using Class Interface: 'CL_ITEM_TREE_CONTROL', Structure: 'MTREEITM' and I pass my value to 'MTREEITM-TEXT.'

Code extract:

data: amount_value type p decimals 2.
CLEAR item.
item-node_key = 'Child1'.
item-item_name = 'Column2'.
item-class = cl_gui_column_tree=>item_class_text.
item-text = amount_value
SHIFT item-text LEFT DELETING LEADING space.
APPEND item TO item_table.

Can you please give me advice as to how I can display numeric output with all its formatting? "1,234,567.89"