Preliminary clinical outcomes of image-guided 3-dimensional conformal radiotherapy for limited brain metastases instead of stereotactic irradiation referral.

To determine the preliminary clinical outcomes of image-guided 3-dimensional conformal radiotherapy (IG-3DCRT) for limited but variably-sized brain metastases (BM). Sixty-two lesions in 24 patients were retrospectively evaluated; out of these patients 75% were ≥ 65 years of age, and 37.5% were categorized into recursive partitioning analysis (RPA) class 3. The median value for the maximum diameter of the lesions was 19 mm (range=4-72 mm). The median sole treatment dose was 36 Gy in 10 fractions. The median survival durations after IG-3DCRT were 12.0 months and 3.2 months for patients categorized into RPA classes ≤ 2 and 3, respectively. Local recurrences occurred in two lesions with a 6-month local control probability of 93.0%. Major toxicities included radiation necrosis in two patients. IG-3DCRT is feasible even for patients with limited BM who are categorized into RPA class 3, and confers clinical outcomes comparable to those of stereotactic radiosurgery, including excellent local control and minimal toxicity even for large tumors. Copyright