Risk factors for seroma formation after axillary lymph node dissection with special focus on the impact of early shoulder exercise

Background: Shoulder and arm dysfunction such as reduced range of motion (ROM) and seroma formation, are common complications following axillary lymph node dissection (ALND). There are conflicting results on the effect of early postoperative exercise on the risk of seroma. This study aims to present incidence of symptomatic seroma formation in a large, population-based cohort, and assesses whether early shoulder mobilization, and other common patient and treatment-related factors are predictors of seroma. Methods: This observational cohort study at the Surgical clinic at Lund University Hospital in Sweden, included 217 consecutive patients who underwent ALND due to breast cancer, cutaneous malignant melanoma (CMM), or carcinoma of unknown primary. A shoulder exercise program was introduced on the first postoperative day and data were collected at routine follow-up 4–6 weeks postsurgery. Main outcome was the strength of the associations between postsurgery exercise and seroma incidence based on logistic regression analyses, supported by data on seroma volume and number of aspirations. Results: Two hundred patients completed the study. The overall seroma incidence was 67.5% and the odds of seroma were lower for patients practicing ROM exercise two times/day versus 0–1 time/day (OR 0.42, 95% CI 0.18–0.96, p =.038). ROM exercise greater than two times/day did not increase the volume, neither did the arm cycling exercise. ALND combined with mastectomy and CMM surgery were associated with larger seroma volumes (1116 ± 1068ml, p =.006) and (1318 ± 920 ml, p <.001), respectively, compared to the breast conserving surgery (537 ± 478ml) while neoadjuvant chemotherapy showed no influence. The effect of age, patients ≥60 years compared to younger, or BMI ≥ 30.0 were weaker (p =.08). Conclusions: Extensive surgical treatments for breast cancer and malignant melanoma produces more seroma, and higher age and obesity may also influence the risk. ROM exercises twice daily predict a lower incidence of seroma following ALND, and more frequent shoulder exercise do not increase the volumes.