Association of postoperative infection and oncological outcome after breast cancer surgery

Postoperative infection and bone sarcoma survival: systematic review of the role of infection in bone sarcoma prognosis

Background

Osteosarcoma (OS) and chondrosarcoma (CS) are primary bone malignancies whose prognoses have stagnated despite advancements in surgical management, chemotherapy, radiation therapy, and immunotherapy. The role of the immune system in generating anti-cancer physiologic responses is critical to prognosis. Prior studies have explored if immune system activation via infection enhances survival in bone sarcomas without a clear consensus.

Methods

This study sought to (I) retrospectively examine the effect of postoperative infection on survival in OS and CS and (II) systematically review the effect of postoperative infection on survival in primary bone malignancies. We performed a retrospective case-control study of 192 patients treated between 1/2000-12/2015 at a single academic sarcoma referral center. Patients with OS or CS undergoing operative resection were included. Eligible patients were grouped by presence of metastasis, and survival was compared between patients with or without postoperative infection. Furthermore, we performed a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines investigating the effect of infection on primary bone malignancy survival. Risk of bias assessment was performed utilizing the ROBINS-I (Risk of Bias in Non-randomized Studies-of Interventions) assessment tool. All presented studies included author information, study population, and overall or disease-free survival results.

Results

One hundred and four patients were included, with 85 without infection (26 metastatic, 59 non-metastatic) and 19 with infection (10 metastatic, 9 non-metastatic). Five-year survival was greatest in patients without metastasis with a postoperative infection (100%), followed by patients without metastasis who were infection-free (80%). Five-year survival was comparatively lower in patients with metastasis who were infection-free (35%) and lowest in patients with metastasis with a postoperative infection (20%). No significant differences were present (P=0.17) on log-rank analysis. Our systematic review collected six studies exploring the impact of infection on primary bone malignancy survival, with two studies reporting significant findings of infection improving survival. Limitations of this review included risk of bias due to confounding, inconsistency comparing outcomes, and differences in patient populations.

Conclusions

This retrospective study and systematic review suggests postoperative infection may play a role in modulating immune response to malignancy. Understanding the synergy between anti-pathogen and anti-cancer responses warrants further investigation as an alternative method of targeted cancer treatment.

Impact of Surgical Care Bundle on Surgical Site Infection after Non-Reconstructive Breast Cancer Surgery: A Single-Centre Retrospective Comparative Cohort Study

BACKGROUND

Surgical-site infections (SSIs) are the commonest cause of healthcare-related infections. Although a surgical care bundle (SCB), defined as a group of preventative measures, is effective in reducing SSIs, it has not been well documented in breast cancer surgery. We aimed to investigate the impact of SCB on SSI.

METHODS

A single-centre retrospective comparative cohort study between 2016 and 2020 was carried out. An SCB including eight different measures was implemented in October 2018 at Sahlgrenska University Hospital, Sweden. Patients who underwent non-reconstructive breast cancer surgery were included for analysis. The primary endpoint was SSI within 30 days after surgery.

RESULTS

Overall, 10.4% of patients (100/958) developed SSI. After SCB implementation, the overall SSI rate reduced from 11.8% to 8.9% (p = 0.15). The largest SSI rate reduction was seen in the subgroup that underwent breast conservation and sentinel lymph node biopsy (SLNB), from 18.8% to 9.8% (p = 0.01). In this multivariable analysis adjusting for patient and treatment factors, the implementation of SCB resulted in a statistically significant reduction in SSI risk (OR 0.63, 95% CI 0.40-0.99, p = 0.04).

CONCLUSIONS

The implementation of a SCB could reduce the incidence of SSI in breast cancer surgery.

Prospective Evaluation of Complications and Associated Risk Factors in Breast Cancer Surgery

Background

Surgical site infection (SSI) is a well-known complication after breast cancer surgery. The primary aim was to assess risk factors for SSI. Risk factors for other wound complications were also studied.

Materials and Methods

In this prospectively registered cohort study, patients who underwent breast-conserving surgery (BCS) or mastectomy between May 2017 and May 2019 were included. Data included patient and treatment characteristics, infection, and wound complication rates. Risk factors for SSI and wound complications were analyzed with simple and multiple logistic regression.

Results

The study cohort consisted of 592 patients who underwent 707 procedures. There were 66 (9.3%) SSI and 95 (13.4%) wound complications. "BMI > 25," "oncoplastic BCS," "reoperation within 24 hour," and "prolonged operative time" were risk factors for SSI with simple analysis. BMI 25-30 and >30 remained as significant risk factors for SSI with adjusted analysis. Risk factors for "any wound complication" with adjusted analysis were "mastectomy with/without reconstruction" in addition to "BMI 25-30" and "BMI > 30."

Conclusion

The only significant risk factor for SSI on multivariable analysis were BMI 25-30 and BMI > 30. Significant risk factors for "any wound complication" on multivariable analysis were "mastectomy with/without reconstruction" as well as "BMI 25-30" and "BMI > 30".