Cancer Res Treat.  2011 Jun;43(2):75-82.

The Role of Stereotactic Ablative Radiotherapy for Early-Stage and Oligometastatic Non-small Cell Lung Cancer: Evidence for Changing Paradigms

• Dahele M
• Senan S

Abstract

A compelling body of non-randomized evidence has established stereotactic ablative lung radiotherapy (SABR) as a standard of care for medically inoperable patients with peripheral early-stage non-small cell lung cancer (NSCLC). This convenient outpatient therapy, which is typically delivered in 3-8 fractions, is also well tolerated by elderly and frail patients, makes efficient use of resources and is feasible using standard commercial equipment. The introduction of lung SABR into large populations has led to an increased utilization of radiotherapy, a reduction in the proportion of untreated patients and an increase in overall survival. In selected patients, the same ablative technology can now achieve durable local control of NSCLC metastases in a variety of common locations including the adrenal glands, bone, brain, and liver. At the same time as this, advances in prognostic molecular markers and targeted systemic therapies mean that there is now a subgroup of patients with stage IV NSCLC and a median survival of around 2 years. This creates opportunities for new trials that incorporate SABR and patient-specific systemic strategies. This selective mini-review focuses on the emerging role of SABR in patients with early-stage and oligometastatic NSCLC.

Keyword

Non-small-cell lung carcinoma; Radiosurgery; Stereotactic body radiotherapy; Clinical trial design

MeSH Terms

Adrenal Glands
Aged
Brain
Carcinoma, Non-Small-Cell Lung
Humans
Liver
Lung
Neoplasm Metastasis
Outpatients
Radiosurgery
Standard of Care

Figure

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  Fig. 1 This peripheral stage I lung tumor (left) was treated using 3 fractions of 18 Gy. The panel on the right side shows the colorwash representing high-dose regions within the planning target volume (red contour).

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  Fig. 2 This patient had initially undergone resection of a T2N0 primary non-small cell lung cancer and single fraction stereotactic radiosurgery for 2 synchronous brain metastases. Eleven mo later, after radiosurgery to 2 more brain metastases, they developed a solitary metastasis in the right adrenal gland measuring 5.3 cm in diameter (left, arrow), which was treated with stereotactic ablative lung radiotherapy to a dose of 60 Gy in 8 fractions. The 60 Gy dose (colored area, middle panel) tightly covers the treatment volume. A computed tomography scan 4 mo later shows a reduction in diameter to 3.3 cm (right, arrow).

• 

  Fig. 3 This patient had previously undergone a single fraction of palliative radiotherapy for a painful vertebral metastasis, and subsequently developed progressive local pain. A magnetic resonance imaging scan (left) revealed progressive vertebral destruction and thecal sac/spinal cord compression. Whilst respecting the tolerance of the spinal cord, stereotactic re-irradiation delivering a minimum dose of 8 Gy per fraction to most of the tumor volume (colorwash) was possible. The patient received 2 fractions, and the maximum point dose in the tumor was 13 Gy per fraction.

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