Citations

Study Design Literature review. Objective Functional secretory tumors metastatic to the spine can secrete hormones, growth factors, peptides, and/or molecules into the systemic circulation that cause distinct syndromes, clinically symptomatic effects, and/or additional morbidity and mortality. En bloc resection has a limited role in metastatic spine disease due to the current paradigm that systemic burden usually determines morbidity and mortality. Our objective is to review the literature for studies focused on en bloc resection of functionally active spinal metastasis as the primary indication. Methods A review of the PubMed literature was performed to identify studies focused on functional secreting metastatic tumors to the spinal column. We identified five cases of patients undergoing en bloc resection of spinal metastases from functional secreting tumors. Results The primary histologies of these spinal metastases were pheochromocytoma, carcinoid tumor, choriocarcinoma, and a fibroblast growth factor 23–secreting phosphaturic mesenchymal tumor. Although studies of en bloc resection for these rare tumor subtypes are confined to case reports, this surgical treatment option resulted in metabolic cures and decreased clinical symptoms postoperatively for patients diagnosed with solitary functional secretory spinal metastasis. Conclusion Although the ability to formulate comprehensive conclusions is limited, case reports demonstrate that en bloc resection may be considered as a potential surgical option for the treatment of patients diagnosed with solitary functional secretory spinal metastatic tumors. Future prospective investigations into clinical outcomes should be conducted comparing intralesional resection and en bloc resection for patients diagnosed with solitary functional secretory spinal metastasis.

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. We aim to systematically review the literature for clinical outcomes following operative interventions and prognostic factors for the treatment of breast metastases to the spine. Specifically, we 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 help recognize which patients will perform better or worse following surgery. Methods 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 studies, 4 cement augmentation studies, and 6 nonsurgical prognostic variable studies met the preset inclusion criteria. All but three studies (two surgical and one cement augmentation) were retrospective in nature, and all studies were of level of evidence IV. Median postoperative survival for metastatic breast cancer was 21.7 months (8.2–36 months), mean rate of pain improvement was 92.9% (76–100%), mean rate of neurological improvement was 63.8% (53–100%), mean rate neurological decline was 4.1% (0–8%), and mean rate LTC 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. Conclusion With respect to clinical outcomes, studies consistently found that surgery resulted in neurological improvement for a majority of patients, with a minimal risk of worsening, and kyphoplasty studies reported a high rate of pain control. Increased postoperative survival 2002 onwards was likely due to FDA approval of new chemotherapies. However, specific factors associated with shorter survival following surgery involve hormone and HER2 receptor status and disease-free interval.