Photodynamic Therapy for the Treatment of Vertebral Metastases

An estimated 10 percent of primary breast, prostate, lung, thyroid and renal cell tumors metastasize to the spine. The majority of these tumors are detected before surgical intervention is required and most patients receive radiation therapy for symptomatic relief. Complete pain control, duration of pain control, high recurrence rates and soft tissue complications make radiation a less than ideal treatment. Also, pre-operative radiation therapy is a significant negative predictor for surgical outcomes. To improve the treatment options for patients with advanced cancer with spinal lesions the research team investigated a new minimally invasive therapy known as photodynamic therapy (PDT) that targets metastatic spine lesions with limited side effects. PDT involves the use of a photo-activated chemotherapeutic agent, given intravenously that when stimulated by non-thermal wavelength-specific light allows for selective ablation of tumor tissue. The light is delivered to the spine through small fiber optic cables using a diode laser. By combining canine and porcine studies the investigators have strong evidence to support that PDT is both safe and effective for the treatment of metastatic tumors in the spine. PDT is targeted, repeatable, minimally invasive and has limited local and systemic side effects. Its use would enhance the treatment options for patients with advanced stage cancer. The goal of the present study is to demonstrate that PDT can be safely and effectively given to treat spinal metastases in patients with advanced stage cancer who have multiple lesions or who have failed radiation or surgical intervention. The effectiveness of this treatment will be determined through clinical and radiographic endpoints along with recurrence and survival. The investigators intend to demonstrate that PDT is a minimally invasive method with low morbidity and mortality by which spinal tumors can be ablated and later stabilized through vertebroplasty, optimizing quality of l