Empty pelvis syndrome as a cause of major morbidity after pelvic exenteration: validation of a core data set.

BACKGROUND Pelvic exenteration (PE) is a potentially curative treatment for advanced pelvic cancers. However, PE procedures are associated with empty pelvis syndrome (EPS), a spectrum of complications including pelvic sepsis, sinus formation, fistulae, and bowel obstruction. Inconsistent reporting has impeded progress in understanding EPS. The PelvEx Collaborative introduced a core data set of descriptors and outcomes to address these issues and the aim of this study was to validate this data set. METHODS An observational cohort study applied the EPS core data set to a prospectively maintained PE database. Patterns of major and minor manifestations were evaluated; logistic regression was used to explore relationships between descriptors and outcomes, and inter-descriptor correlation was assessed using Cramer's V. RESULTS EPS occurred in 32.1% of patients (105 of 327) and was the leading cause of major morbidity. Infected pelvic collections (occurring in 23.5%) were associated with subsequent chronic sinus formation (OR 3.08, P = 0.01) and fistulae (P = 0.05). The risk of EPS increased with external beam radiotherapy (OR 1.01 per 1 Gy, P = 0.01), sacrectomy (OR 3.78, P < 0.001), total cystectomy (OR 2.46, P = 0.001), internal iliac vessel ligation (unilateral OR 1.94, P = 0.045; bilateral OR 3.65, P < 0.001), and infralevator exenteration (OR 3.69, P < 0.001). Omentoplasty reduced pelvic bowel obstruction (OR 0.27, P = 0.004) and perineal flaps were linked to a higher rate of reconstruction-related major morbidity compared with biological mesh alone (20.8% versus 1.2% respectively, P = 0.002). CONCLUSION The PelvEx Collaborative core data set standardizes reporting of EPS, with this study detailing the acute and chronic complications arising as a consequence. Biological mesh was associated with reduced reconstruction-related morbidity compared with perineal flaps. Further validation in additional cohorts is required to address potential confounding factors.