Read Rich Text cells of a XLSX Excel file without COM

I need to read Excel files fully formatted, that some times have rich text cells. I am able to read old format Excel files with (xlrd). However rich text in XLSX files is not supported by xlrd library.

To be able to read these files, I have done a hack through pywin32com and save it as xls. I would like to avoid this solution as I may lose information or formatting styles that are not supported in Excel 97/2003.

Openpyxl is not good for me as it does not support rich text and it is lost when is read by that library.