Stereotactic body radiation therapy for spinal metastases

Oligometastasis and oligo-recurrence: more than a mirage

The standard treatment choice for cancer metastasis has been systemic management, including cytotoxic chemotherapy, hormonal manipulation, and targeted therapy. Emerging evidence has shown an oligometastatic state, an intermediate state between limited primary cancer and polymetastatic cancer, in which local therapy for metastatic lesions results in satisfactory survival comparable to non-metastatic disease. We provide a comprehensive introduction of evidence from experimental and clinical studies in favor of the oligometastatic phenotype, we review the efficacy and safety of surgery and stereotactic body radiotherapy in the treatment of oligometastases, and finally, we discuss the way to differentiate the oligometastatic state from polymetastasis.

Comparison of external radiotherapy and percutaneous vertebroplasty for spinal metastasis

AIM

To compare the efficacy of external radiotherapy (ERT) and percutaneous vertebroplasty (PVP) for spinal metastasis.

METHODS

A total of 137 patients with 174 spinal metastases between June 2006 and April 2009 in our hospital were reviewed. For their spinal metastasis, 52 patients received ERT; 46 patients received PVP; and 39 patients received both ERT and PVP. Pain and neurological deficit response, overall survival, and side effects were evaluated.

RESULTS

ERT combined with PVP achieved pain remission in 84.8% of the patients, which was higher than ERT (72.5%) or PVP (76.3%) alone. It also showed a higher remission rate of neurological deficits (50%) than ERT (18.2%) or PVP (11.1%) alone. Toxicities from the employed treatments were mild. The Karnofsky Performance Score and visceral or brain metastases were the significant influencing factors for overall survival. Patients with spinal metastases derived from breast cancer had a significantly better overall survival than those whose spinal metastases were derived from lung cancer.

CONCLUSION

ERT combined with PVP can be a more effective treatment for spinal metastases; however, prospective randomized trials are needed to draw any definitive conclusion.

Stereotactic ablative radiotherapy delivered by image-guided helical tomotherapy for extracranial oligometastases

PURPOSE

To investigate the outcomes and risk factors of patients treated with stereotactic ablative radiotherapy (SABR) delivered by image-guided helical tomotherapy (HT) for extracranial oligometastases.

METHODS

From August 2006 through July 2011, 42 consecutive patients (median age 69 years [range 16-87]) with oligometastases (≤3) received HT to all known cancer sites (lung, n = 28; liver, n = 12; adrenal, n = 2). Prognostic factors were assessed by Cox's proportional hazards regression analysis.

RESULTS

A total of 60 lesions were treated with hypofractionated HT (median dose 39 Gy [range 36-72.5]; median dose per fraction 12 Gy [range 5-20]). Complete or partial response was observed in 40 (54 %) patients. With a median follow-up period of 15 months, 1- and 2-year overall survival (OS) was 84 and 63 %, respectively; and 1- and 2-year local control (LC) was 92 and 86 %, respectively. Four patients had pneumonitis Grade ≥2 and two patients had lower gastrointestinal toxicity Grade ≥2. Only the lack of complete/partial response was associated with higher risk of mortality on univariate (HR = 3.8, P = 0.04) and multivariate (HR = 6.6, P = 0.01) analyses.

CONCLUSIONS

SABR delivered by image-guided HT is well tolerated and offers adequate LC with low acute morbidity in patients with extracranial oligometastatic disease. We found that the response to HT was the only predictor for OS.