PurposeTo evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS).Materials and MethodsFrom June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21.ResultsThe median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression.ConclusionThe results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

289 Background: Gallbladder cancer (GBC) is a relatively uncommon malignancy with high recurrence rate and poor prognosis, even after curative resection. Although postoperative radiotherapy (RT) has been tried to improve the poor results of surgery alone, the benefit of postoperative RT for GBC is still a matter of debate. The present study aimed to evaluate the effect of postoperative RT on locoregional control (LRC), disease-free survival (DFS), and overall survival (OS) in patients with GBC. Methods: Between March 1998 and July 2009, 228 patients with GBC (T2-3 N0-2) underwent surgical resection with potentially curative aim (R0 or R1) at Asan Medical Center. Among the 228 patients, 86 received postoperative RT (RT group) with or without concurrent chemotherapy, and 142 did surgery alone (no-RT group). All patients with postoperative RT received three-dimensional conformal radiotherapy, and the median radiation dose was 50 Gy (range, 45-60 Gy) at 1.8 or 2.0 Gy/fraction daily. Among them, 57 patients (66.3%) had concurrent chemotherapy based on 5-fluorouracil. Results: The median follow-up time was 90 months (range, 35-96 months) for the surviving patients. Although RT group had significantly more advanced disease in overall stage (p = 0.005), T stage (p = 0.002), N stage (p = 0.010), and higher rate of R1 resection (p = 0.027), the 3-year LRC was 78% for RT group and 66% for no-RT group (p = 0.088). Also, there was no significant difference in the 3-year DFS and OS: 51% vs. 52% (p = 0.994) and 53% vs. 56% (p = 0.541), respectively. In multivariate analysis, postoperative RT was a significant predictive factor of improved LRC (p = 0.011), DFS (p = 0.016) and OS (p = 0.036). Conclusions: Although RT group had more adverse risk factors, the treatment outcomes of RT group were similar to those of no-RT group. Moreover, postoperative RT was a significant predictor of improved LRC, DFS and OS after adjusting these factors. These results suggest that postoperative RT might be effective in locoregional control and survival for patients with GBC.

BackgroundUtility weight, a measure of health-related quality of life, is used in disease burden measurements and economic evaluations. In this study, we used the visual analogue scale (VAS) and standard gamble (SG) method to determine the utility weights of lung cancer health states in South Korea from a societal perspective.MethodsSix hypothetical health states for lung cancer or a related health state reflective of disease severity were developed: 1) Stage I, 2) Stage II, 3) Stage IIIa, 4) Stage IIIB, 5) Stage IV, and 6) Pulmonary nodule. The description of each health state description was divided into four parts: diagnosis, symptoms, treatment, and progression and prognosis. A total of 515 representative adult Korean participants used a VAS and SG to evaluate these six health states via face-to-face computer-assisted interviews. The means, standard deviations, and median utility weights of the six health states were estimated by valuation method.ResultsThe two valuation methods of the scenarios yielded the same mean utility rankings. Pulmonary nodule received the highest rank (VAS, 0.66 and SG, 0.83), whereas Stage 4 was assigned the lowest rank (VAS, 0.09 and SG, 0.31). For all health states, the mean utility weights calculated using the SG were greater than those calculated using the VAS. The differences between the utility weights obtained using the two valuation methods ranged from 0.14 (Stage I) to 0.22 (Stage IV). The two approaches tended to yield larger differences for more severe stages.ConclusionsThis study determined utilities for squamous cell lung cancer that will be useful for estimating the burden of lung cancer and for conducting economic evaluations of lung cancer interventions.Electronic supplementary materialThe online version of this article (10.1186/s12885-018-4960-y) contains supplementary material, which is available to authorized users.