Researchers have found that stereotactic body radiotherapy (SBRT) may be an effective treatment for patients with early-stage lung neuroendocrine tumors, according to a new study published by Oliver et al in the International Journal of Radiation Oncology • Biology • Physics.
Background
Primary lung neuroendocrine tumors represent about 1% to 2% of all lung cancer cases. Only 2,000 to 4,500 patients in the United States are diagnosed with the disease each year. The common treatment for early-stage lung neuroendocrine tumors is surgery—but this may not be an option for all patients.
Treatment with SBRT is designed to deliver high doses of radiation to precise areas of a tumor, minimizing damage to surrounding normal cells. Patients receiving SBRT often have less toxicity and side effects compared to conventional radiotherapy.
“SBRT is commonly used as a treatment for early-stage non–small cell lung cancer, and our results show strong tumor control. This suggests that SBRT may also be effective for lung neuroendocrine tumors,” explained first study author Daniel Oliver, MD, Assistant Member of the Section of Neuro-Oncology and Supportive Care in the Department of Radiation Oncology at the Moffitt Cancer Center. “In fact, SBRT is increasingly being used to treat early-stage lung neuroendocrine tumors in clinical practice—despite the lack of consensus recommendations for this approach and very limited data on its effectiveness and toxicity in [these patients].”
Study Methods and Results
In the new study, the researchers performed a retrospective analysis of 48 lung neuroendocrine tumors from 46 patients who were treated with SBRT to assess its efficacy and long-term outcomes. They discovered that SBRT provided local control rates of 97% at 3 years, as well as 91% at 6 and 9 years—and only one regional recurrence occurred. The treatment was also well tolerated, with only one case of low-grade SBRT-related toxicities reported.
Since lung neuroendocrine tumors are so rare, it may be difficult to initiate clinical trials for these patients. Therefore, the researchers noted that a randomized trial will likely never be conducted to compare SBRT to surgery. Despite this, the results of the study were comparable to historical populations of patients with lung neuroendocrine tumors who were treated with surgery—which is particularly notable given that many patients treated with SBRT typically have additional health conditions that can make treatment difficult and result in poorer outcomes.
Conclusions
“The current study is the largest and first multi-institutional series evaluating local control, toxicity, and dosimetric outcomes with SBRT for early-stage lung neuroendocrine tumors. Our results suggest that while surgery provides excellent outcomes, SBRT should be considered [as] another treatment option for this patient population,” concluded senior study author Stephen Rosenberg, MD, Assistant Member of the Section of Thoracic Oncology and Director of Magnetic Resonance Imaging–Guided Radiotherapy in the Department of Radiation Oncology at the Moffitt Cancer Center.
Disclosure: For full disclosures of the study authors, visit redjournal.org.
