Introduction: Surgical treatment and cement augmentation procedures are effective palliative techniques for the treatment of symptomatic spinal metastases. However, clinical results specific to a breast cancer cohort are generally lacking.
Methods: We systematically reviewed the literature to describe the survival and clinical outcomes of surgery and cement augmentation procedures for breast metastases to the spine and to determine prognostic variables that may predict patient outcomes following surgery. We performed a literature review using Pubmed to identify articles that reported outcomes and/or prognostic factors of the breast cancer patient population with spinal metastases treated with any surgical technique since 1990.
Results: A total of 19 surgical, 4 cement augmentation, and 6 nonsurgical prognostic variable studies met the preset inclusion criteria. All but 3 studies were retrospective in nature, and all studies were of level IV evidence. The median postoperative survival for metastatic breast cancer was 21.7 mo (8.2-36 mo), the mean rate of any pain improvement was 92.9%, the mean rate of neurological improvement was 63.8%, the mean rate of neurological decline was 4.1% (0-8%), and the local tumor control rate was 92.6% (89-100%). Kyphoplasty studies reported a high rate of pain control in selected patients. Negative prognostic variables included: hormonal (estrogen and progesterone) and HER2 receptor refractory tumor status, high degree of axillary lymph node involvement, and short disease-free-interval (DFI). All other clinical or prognostic parameters were of low or insufficient strength.
Conclusions: With respect to clinical outcomes, surgery consistently yielded neurological improvements in patients presenting with a deficit with a minimal risk of worsening. Kyphoplasty studies reported a high rate of pain control. The observed improvement in postoperative survival beyond the year 2002, likely reflects FDA approval of new chemotherapies. However, negative prognostic factors associated with shorter survival following surgery include ER/PR negativity, HER2 negativity, and a short DFI.
Patient Care: This research provides surgeons with information to effectively counsel patients and determine appropriate treatment paradigms based on life expectancy for patients diagnosed with a breast cancer metastasis to the spine.
Learning Objectives: By the conclusion of this session, participants should be able to describe the clinical outcomes following operative procedures and evaluate prognostic factors in the context of spinal breast metastases.