Standardization of morbidity assessment in breast cancer surgery using the Clavien Dindo Classification

Introduction: There are no published data on standardized scoring systems for morbidity after breast cancer surgery. Aim of the study was to establish the Clavien Dindo Classification (CDC) as assessment tool and to identify risk factors for morbidity after breast surgery investigating new techniques including oncoplastic surgery and neoadjuvant chemotherapy.

Patients and methods: Between 2008 and 2010, data were retrospectively evaluated from 485 women with breast cancer who underwent surgery at a university hospital. The CDC was used to assess the severity of postoperative complications. Multivariable analyses were adjusted by body-mass index, smoking, diabetes mellitus and tumour size.

Results: Overall complications (CDC 1-4) were reported in 28.7%. Second surgery related to major complications (CDC 3-4) was mandatory in 4.7%. Axillary dissection was an independent predictor for CDC 1-4 in all patients (P = 0.008, OR of 1.81, 95%CI 1.17-2.82). We found no independent predictor for CDC 3-4. Oncoplastic surgery increased the rate of wound infections (P = 0.010, OR: 2.94, 95%CI 1.30-6.67) and necroses (P < 0.001, OR: 8.38, 95%CI 3.28-21.4). Axillary dissection elevated wound infection (P = 0.040, OR: 2.07, 95%CI 1.03-4.14) and seroma rates (P < 0.001, OR: 2.46, 95%CI 1.51-4.01). Neoadjuvant chemotherapy had no impact on morbidity.

Conclusion: The CDC is a valid assessment tool for future clinical trials and may be useful for hospital quality control. While axillary dissection and oncoplastic surgery raised morbidity, no single factor predicted for morbidity related second surgery.