Postoperative complications and their risk factors in breast cancer patients treated with neoadjuvant chemotherapy

Although neoadjuvant chemotherapy (NACT) has become established treatment of breast cancer, its impact on postoperative complications varies across studies. Furthermore, association between known risk factors and different kind of complications is unclear. We aimed to characterize the type, rate and risk factors of postoperative complications in a cohort of breast cancer patients treated with NACT.

A retrospective review of breast cancer patients treated with NACT in Helsinki University Hospital between 2020 and 2022 was performed. Complications were graded according to Clavien Dindo classification. Risk factors were identified for overall complications, chronic seroma (defined as a seroma requiring more than five needle aspirations) and hematoma or infection in a multivariable logistic regression model.

Out of 4432 patients, 377 met the inclusion criteria. Of these, 216 (57 %) had 314 postoperative complications, commonly seroma (n = 204, 65 %), wound or seroma infection (n = 42, 13 %) and problems with wound healing (n = 19, 6 %). In multivariable analyses, higher age (OR = 1.03, p = 0.003) and undergoing mastectomy (OR = 6.45, p < 0.001) and/or axillary lymph node dissection (ALND) (OR = 2.54, p < 0.001) were independent risk factors of overall complications. Hypertension increased the odds of chronic seroma (OR = 2.26, p = 0.035) and overweight increased the odds of hematoma or infection (OR = 1.06, p = 0.012).

Postoperative complications were common yet in most cases treated in an outpatient setting. Patients with higher age and BMI, and those operated with mastectomy and/or ALND were in greater risk of developing postoperative complications. This study also identified that hypertension could have a role in the development of chronic seroma.