There is no simple alternative while you use Word, but you can automate it with a macro that performs the steps e.g.
Code:
Sub CheckDuplicates()
Dim oTable As Table
Dim oCell1 As Range, oCell2 As Range
Dim i As Long
If Not Selection.Information(wdWithInTable) Then
Beep
MsgBox "The cursor is not in a table?"
GoTo lbl_Exit
End If
Set oTable = Selection.Tables(1)
oTable.Sort ExcludeHeader:=False, FieldNumber:="Column 2", _
SortFieldType:=wdSortFieldAlphanumeric, SortOrder:=wdSortOrderAscending
DoEvents
For i = 2 To oTable.Rows.Count - 1
Set oCell1 = oTable.Rows(i).Cells(2).Range
oCell1.End = oCell1.End - 1
Set oCell2 = oTable.Rows(i + 1).Cells(2).Range
oCell2.End = oCell2.End - 1
If oCell1.Text = oCell2.Text Then
oCell1.HighlightColorIndex = wdYellow
oCell2.HighlightColorIndex = wdYellow
End If
Next i
oTable.Sort ExcludeHeader:=False, FieldNumber:="Column 1", _
SortFieldType:=wdSortFieldNumeric, SortOrder:=wdSortOrderAscending
lbl_Exit:
Set oTable = Nothing
Set oCell1 = Nothing
Set oCell2 = Nothing
Exit Sub
End Sub