Oracle Database LOB increases untypical
Is there a way to check the content of SYS_LOB0000119621C00011$$?


Yes you can first look at dba_lobs view to check which table/column is associated with this segment.


  What could be the reason for this growth if this is not coming from
  the users?


Maybe one huge file has been inserted in your table. You can use DBMS_LOB.GETLENGTH(column_name) to find the size of each lob.

select filename, DBMS_LOB.GETLENGTH(filecontent) from fileentry order by 2;