2.2 Data extraction
Data extraction and quality assessment of all included studies were independently performed by 2 authors (MF and BE). Controversies were solved by discussion or consultation with another author (RS). Basic information such as patient demographics, histopathology, presenting complaints, surgical approaches and post-operative complications were recorded. All included papers were clinical studies focusing on surgical management of PPS tumors using different approaches and the post-operative complication or sequelae.