Rates of Reconstruction Failure in Patients Undergoing Immediate Reconstruction With Tissue Expanders and/or Implants and Postmastectomy Radiation Therapy

Breast Reconstruction With Postmastectomy Radiation: Choices and Tradeoffs

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice. A 45-year-old premenopausal woman presented with multifocal cancer in the right breast, with lesions at 1:00 and 4:00, the largest measuring approximately 3 cm on exam, and multiple palpable right axillary lymph nodes. A core biopsy confirmed invasive ductal carcinoma, grade 2 of 3, that was estrogen receptor positive, progesterone receptor positive, and HER2 negative. Fine needle aspiration of a right axillary node confirmed metastatic carcinoma. A positron emission tomography (PET)/ computed tomography done before starting chemotherapy demonstrated an absence of metastatic disease with expected avidity in two separate breast masses and multiple conglomerated 1-2 cm level I and II axillary lymph nodes. She received neoadjuvant chemotherapy with doxorubicin plus cyclophosphamide, followed by paclitaxel, and had a complete clinical response with resolution of the breast and axillary masses on exam. A repeat PET/computed tomography demonstrated reduced size of the breast and axillary disease, and no significant residual PET avidity. Her breast surgeon recommended a right mastectomy with axillary node dissection. As part of her multidisciplinary treatment plan, she consulted with two plastic surgeons to discuss reconstruction options. Plastic Surgeon A advised placement of an implant at the time of mastectomy while Surgeon B contrasted the pros and cons of an autologous transverse rectus abdominis muscle flap reconstruction with an implant based reconstruction. Surgeon B believed that autologous reconstruction would yield the best long-term cosmetic outcome. Before making her surgery decision, the patient consulted with a radiation oncologist to discuss the effect radiation may have on her reconstruction outcome.

Outcomes of Post Mastectomy Radiation Therapy in Patients Receiving Axillary Lymph Node Dissection After Positive Sentinel Lymph Node Biopsy

PURPOSE

We sought to determine the rate of postmastectomy radiation therapy (PMRT) among women treated with axillary lymph node dissection (ALND) after positive sentinel lymph node (SLN) biopsy results and to establish the effect of negative ALND results and PMRT on locoregional recurrence (LRR) and overall survival (OS).

METHODS AND MATERIALS

All patients were treated with mastectomy and ALND after positive SLN biopsy results. All patients had clinical N0 or NX disease at the time of mastectomy and received no neoadjuvant therapy. The presence of lymphovascular space invasion, presence of multifocality, number of positive SLNs and non-SLNs, clinical and pathologic stage, extranodal extension, age, and use of PMRT were evaluated for significance regarding the rates of OS and LRR.

RESULTS

A total of 345 patients were analyzed. ALND after positive SLN biopsy results was negative in 235 patients (68.1%), and a total of 112 patients (32.5%) received radiation therapy. On multivariate analysis, only pathologic stage III predicted for lower OS (hazard ratio, 3.32; P<.001). The rate of 10-year freedom from LRR was 87.9% and 95.3% in patients with positive ALND results and patients with negative ALND results, respectively. In patients with negative ALND results with ≥3 positive SLNs, the rate of freedom from LRR was 74.7% compared with 96.7% in those with <3 positive SLNs (P=.009). In patients with negative ALND results, ≥3 positive SLNs predicted for an increase in LRR on multivariate analysis (hazard ratio, 10.10; P=.034).

CONCLUSIONS

A low proportion of cT1-2, N0 patients with positive SLNs who undergo mastectomy receive PMRT after ALND. Even in this low-risk cohort, patients with ≥3 positive SLNs and negative ALND results are at increased risk of LRR and may benefit from PMRT.