Convert tiff byte array to pdf byte array using itextsharp with C#

I am using fileupload control to save a tiff and PDF files in SQL database. I am saving the file in byte format.

I am using the below code to display in PDF file where the byte array is a original PDF byte array stream.

 byte[] image;
            dr = cmd.ExecuteReader();
            dr.Read();
            image = ((byte[])dr["DocImage"]);
            Response.Clear();
            MemoryStream ms = new MemoryStream(image);
            Response.ContentType = "application/pdf";
            Response.AddHeader("Content-Disposition", "attachment; filename=" + LNKBTN.Text);
            Response.AddHeader("Content-Length", image.Length.ToString());
            //Response.WriteFile(LNKBTN.FullName);
            Response.Buffer = true;
            ms.WriteTo(Response.OutputStream);
            Response.End();
            cn.Close();

But what is needed to be done is case of retreiving a TIFF byte array. After retreiving the byte array of the TIFF file from the database I need to convert the TIFF byte array to PDF bytes and I need to show the content in PDF file. How can i achieve the same using Itextsharp.

Please post some code snippet to achieve the same.

Thanks in advance...