Risk factors for local tumor progression after RFA of pulmonary metastases: a matched case-control study.

OBJECTIVES: Curative treatment of oligometastatic pulmonary disease aims at eradication of all metastases. Radiofrequency ablation (RFA) has been shown to be an efficient method and the frequency of local tumor progression (LTP) should be minimized. The objective of this study was to determine the morphological and treatment-related risk factors for LTP after RFA of pulmonary metastases. MATERIALS AND METHODS: All patients treated with RFA for pulmonary metastases from 2002 to 2014 were reviewed. All LTPs from 2011 to 2014 were individually matched on the basis of tumor size, number, and histology. In total, 48 LTPs and 112 controls were blindly analyzed for morphological factors including vicinity of bronchus and vessels as well as treatment-related factors such as the size of the ablation zone and ablation margins. RESULTS: In the simple regression analysis, the significant predictive variables were ≤ 5-mm distance to a large bronchus (OR = 4.94; p = 0.0095) or large vessel (OR = 7.09; p < 0.001), minimal ablation margin (≤ 5 mm (OR = 42.67; p < 0.001), and a central-peripheral ablation offset/ablation zone size > 0.36 (OR = 13.83; p = 0.013). In the multiple regression model, only a minimal ablation margin ≤ 5 mm remained a significant risk factor for LTP. CONCLUSION: Only the minimal ablation margin remains significant in the multiple regression analysis; the other factors are presumably surrogates of an insufficient ablation margin. Improvement of lung RFA outcomes can probably be obtained by immediate post RFA evaluation of ablation margins to ensure a minimal ablation margin of at least 5 mm. KEY POINTS: • A distance < 5 mm to a bronchus or vessel of over 3 mm diameter is associated with insufficient ablation margin and thus risk factors for local tumor progression after pulmonary radiofrequency ablation. • A minimal ablation margin of > 5 mm after pulmonary RFA is associated with significantly less local tumor progression and should be looked for at the end of treatment session before needle removal in order to decrease local tumor progression. • Tumor location, pleural contact, occurrence of intra-alveolar hemorrhage, pulmonary atelectasis, and pneumothorax are not associated with an increased risk of local tumor progression.

High subcutaneous adipose tissue predicts the prognosis in metastatic castration-resistant prostate cancer patients in post chemotherapy setting.

BACKGROUND: Cancer studies have shown that body mass index (BMI), skeletal muscle mass (SMM) and adipose tissue indexes are linked to overall survival (OS) and progression-free survival (PFS). New treatments (abiraterone acetate, enzalutamide cabazitaxel, radium-223, sipuleucel-T) have improved patient outcomes in metastatic castration-resistant prostate cancer (mCRPC). Our objective was to analyse whether body composition parameters exert a prognostic role in mCRPC patients treated with next generation of androgen receptor (AR) axis inhibitors (abiraterone and enzalutamide). METHODS: All mCRPC patients from our institution who were enrolled in two prospective trials, assessing the efficacy of abiraterone acetate and the efficacy of enzalutamide, were selected. SMM, visceral and subcutaneous adipose tissue (SAT) indexes were assessed with computed tomography imaging by measuring cross-sectional areas of the tissues. RESULTS: In the 120 patients with available data, median OS and PFS were respectively: 16 months (95% confidence interval [CI] = 12-19) and 4 months (95% [CI] = 3-6). OS was associated with the SAT index: median survival was 15 months (95% [CI] 9-18) for patients with a SAT index < median value and 18 months (95% [CI] 13-30) for patients with a SAT index above (P = 0.008). In multivariate analyses, only the occurrence of visceral metastasis (P = 0.004), pain (P = 0.015) and SAT index (P = 0.036) were statistically significant predictors of OS. From baseline to 3 months, the SMM index loss was 2.49 ± 0.44 cm(2)/m(2) (P < 0.001) corresponding to nearly 3.4 kg of muscle loss. CONCLUSIONS: High volume of SAT is independently associated with overall survival in mCRPC patients treated with next generation AR axis inhibitors.