Spinal Metastasis Surgery and Stereotactic Radiosurgery: Wound Healing and Complications
Meeting Highlight from the 31st Annual Meeting of the Section on Disorders of the Spine and Peripheral Nerves—Spine Summit 2015
Vijay Yanamadala, MD, a neurosurgeon at Massachusetts General Hospital in Boston presented, Morbidity of Repeat Surgery for Recurrent Spinal Metastases Following Combined Separation Surgery and Stereotactic Radiosurgery during the 31st Annual Meeting of the Section on Disorders of the Spine and Peripheral Nerves—Spine Summit 2015 in Phoenix, AZ.
Stereotactic radiosurgery (SRS) for postoperative spinal tumor control was the focus of Dr. Yanamadala’s study. “SRS is really a powerful tool for the treatment of spinal metastases. Local control rates in numerous retrospective studies are approximately 90% or more; this means that there is approximately a 10% failure rate,” stated Dr. Yanamadala. Failure may lead to disease progression and/or epidural compression requiring more surgery. In addition, with ever-improving systemic therapy, patients are living longer. Furthermore, SRS has demonstrated durability of local control irrespective of the type of tumor.
According to Dr. Yanamadala, there are two primary indications for SRS:
- Postoperative adjuvant as an alternative to conventional radiation
- Salvage therapy for previously irradiated sites in patients who demonstrate progression of local disease
“The concept of separation surgery followed by SRS is well-established as an effective multimodal treatment option. In numerous studies, it’s really become a treatment paradigm,” Dr. Yanamadala explained. However, there is limited data regarding the complications and outcomes when additional surgery is necessary after separation surgery and SRS.
About the Study
Thirty-seven (37) patients, who underwent separation surgery followed by stereotactic radiosurgery (18Gy, 1 fraction) at the authors’ institution between 2012 and 2014, were identified and retrospectively reviewed. Tumor histologies included breast, lung, renal cell, hepatocellular, and esophageal. The patients were ambulatory but mechanical pain limited function.
Five (5) patients required additional surgery for decompression due to local tumor recurrence (ages 54-77; 4 male, 1 female; 3 thoracic, 2 lumbar). Four (4) patients had evidence of spinal cord or cauda equina compression, and 1 had symptomatic pathological fracture. “In all of these cases, we did repeat decompressive surgery and thoracic vertebrectomy with cage reconstruction and extension of the previous fusion construct,” indicated Dr. Yanamadala.
Of the 5 patients, 3 had previously undergone conventional radiation at 13, 39, and 48 months. The 4 patients with local progression to compression presented 6 to 23 months after SRS (mean 12.5 months). The patient with the vertebral fracture presented 12 months following SRS.
Mean follow up of 5.8 months was limited by patient mortality: 3 of the 5 patients died during this time period, with a range of survivals from 3 months to 1 year. Four of the 5 patients experienced complications:
- Three (3) patients experienced problems related to wound healing: 2.6 months to full wound closure
- One (1) patient required 3 surgeries, plastic surgery with flap reconstruction
- One (1) patient developed an epidural hematoma requiring immediate surgery
Dr. Yanamadala summarized, “Similar to conventional radiation, wound complications are the main issue with surgery after stereotactic radiosurgery.” Clearly, patient survival is poor and multiple factors—progression of underlying systemic disease, total radiation dose, concurrent chemotherapy and/or immunotherapy—contribute to wound complications. “But, importantly, all of these patients had improvement in their functional status; all of these patients had neurological improvement, including leg strength and ambulation. So what’s clear is there’s a balance here between a surgery, which is clearly morbid in a patient substrata that’s clearly having a lot of comorbidities, but there is a clear improvement in quality of life for these patients as well,” concluded Dr. Yanamadala.