Smoking Significantly Impacts Persistence Rates in Embolized Pulmonary Arteriovenous Malformations in Patients with Hereditary Hemorrhagic Telangiectasia.

Background Embolization is the standard of care for treatment of pulmonary arteriovenous malformations (PAVMs). Persistence of PAVMs after embolization occurs for undefined reasons but may include inflammation related to smoking in dysregulated angiogenesis. Purpose To determine whether patients with hereditary hemorrhagic telangiectasia (HHT) who smoke tobacco are more prone to PAVM persistence after embolization. Materials and Methods Patients with HHT treated for PAVMs between January 2000 and August 2017 were retrospectively identified. Only PAVMs with no previous treatment and patients with both clinical and imaging follow-up were included. Age, sex, PAVM characteristics (size, complexity, and location), embolization material used, microcatheter type, smoking history, active tobacco use, and other risk factors for arterial disease were analyzed by using a multivariate Cox proportional hazards model to determine risk factors for persistence. Results Five-year persistence-free survival rates in nonsmokers, smokers of 1-20 pack-years, and smokers of more than 20 pack-years were 12.2%, 21.9%, and 37.4% respectively. Smokers with more than 20 pack-years relative to nonsmokers had greater risk of persistence after adjusting for arterial feeder size (hazard ratio, 3.8; 95% confidence interval [CI]: 1.5, 10.0; P = .007). Patients who reported active tobacco use at the time of PAVM embolization had a 5-year cumulative incidence of persistence of 26.3% compared with 13.5% in inactive smokers. After adjusting for arterial feeder size, the risk of persistence was greater in tobacco users versus inactive smokers at the time of treatment (hazard ratio, 2.4; 95% CI: 1.2, 4.7; P = .01). Conclusion Smoking is associated with pulmonary arteriovenous malformation persistence after embolization in patients with hereditary hemorrhagic telangiectasia. Online supplemental material is available for this article. See also the editorial by Trerotola and Pyeritz in this issue.

Percutaneous Cryoablation of Solitary, Sporadic Renal Cell Carcinoma: Outcome Analysis Based on Clear-Cell versus Papillary Subtypes.

PURPOSE: To evaluate treatment outcomes with percutaneous cryoablation (PCA) based on renal cell carcinoma (RCC) histology. METHODS AND MATERIALS: Patients treated with PCA for a solitary, sporadic stage T1a RCC from 2003 to 2016 were identified from a single institution's renal ablation registry. Patients with multiple tumors, history of RCC, or genetic syndromes associated with RCC (n = 60); no specific RCC subtype determined from core biopsy (n = 66); RCC subtype other than clear-cell or papillary (n = 7); or less than 3 mo of follow-up imaging (n = 5) were excluded. In total, 173 patients met study inclusion criteria. Oncologic outcomes, clinical outcomes, and complications were evaluated based on tumor subtype. RESULTS: Of the 173 patients who underwent PCA for a stage T1a RCC, 130 (75%) had clear-cell RCC (ccRCC) and 43 (25%) had papillary RCC (pRCC). Median tumor size was 2.9 cm (range, 1.3-4.0 cm). Technically successful cryoablation was achieved in all 173 patients. Local tumor recurrence developed in 6 patients with ccRCC (4.6%), new renal tumors developed in 1 patient (0.8%), and metastatic RCC developed in 1 patient (0.8%) who also had local tumor recurrence. No patients with pRCC showed local tumor recurrence, new renal tumors, or metastatic disease. The 5-year disease-free survival rate in patients with ccRCC was 88%, compared with 100% in patients with pRCC (P = .48). Nine patients (5.2%), all with ccRCC, experienced major complications (P = .11). CONCLUSIONS: Percutaneous ablation is a viable treatment option for patients with clinical stage T1a pRCC and ccRCC. Percutaneous ablation may be a very favorable treatment strategy particularly for pRCC.

Outcomes After Cryoablation Versus Partial Nephrectomy for Sporadic Renal Tumors in a Solitary Kidney: A Propensity Score Analysis.

BACKGROUND: While partial nephrectomy (PN) is considered the standard approach for a tumor in a solitary kidney, percutaneous cryoablation (PCA) is emerging as an alternative nephron-sparing option. OBJECTIVE: To compare outcomes between PCA and PN for tumors in a solitary kidney. DESIGN, SETTING, AND PARTICIPANTS: Patients who underwent PCA or PN between 2005 and 2015 for a single primary renal tumor in a solitary kidney were identified using Mayo Clinic Registries. Exclusion criteria were inherited tumor syndromes and salvage procedures. INTERVENTION: PCA and PN. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: To achieve balance in baseline characteristics, we used inverse probability of treatment weighting (IPTW) based on propensity to receive treatment. The risk of having a post-treatment complication and percent drop in estimated glomerular filtration rate (eGFR), as well as the risks of local/ipsilateral recurrence, distant metastasis, and cancer-specific mortality, were compared between groups using logistic, linear, and Fine-and-Gray competing risk regression models. RESULTS AND LIMITATIONS: The cohort included 118 patients (PCA: 54; PN: 64) with a median follow-up of 47 mo (interquartile range 18, 74). In unadjusted analyses, PCA was associated with a lower risk of complications (15% vs 31%; odds ratio [OR]=0.38; 95% confidence interval [CI] 0.15, 0.96; p=0.04). However, upon accounting for baseline differences with IPTW adjustment, there was no longer a significant difference in the risk of complications (28% vs 29%; OR=0.95; 95% CI 0.53, 1.69; p=0.9). There were no significant differences between PCA and PN in percentage drop in eGFR at discharge (mean: 11% vs 16%; ß=-5%; 95% CI -13, 3; p=0.2) or at 3 mo (12% vs 9%; ß=3%; 95% CI -3, 10; p=0.3). Likewise, no significant differences were noted in local recurrence (HR=0.87; 95% CI 0.38, 1.98; p=0.7), distant metastases (HR=0.60; 95% CI 0.30, 1.20; p=0.2), or cancer-specific mortality (HR=1.13; 95% CI 0.32, 3.98; p=0.8). Limitations include the sample size, given the relative rarity of renal masses in solitary kidneys. CONCLUSIONS: Our study found no significant difference in complications, renal function outcomes, and oncologic outcomes between PN and PCA for patients with a tumor in a solitary kidney. Validation in a larger multi-institutional analysis may be warranted. PATIENT SUMMARY: Partial nephrectomy (surgery) and percutaneous cryoablation are both options for treating a kidney tumor while preserving the normal portion of the kidney. In patients with a tumor in their only kidney, we found no difference in the risk of complications, kidney function outcomes, or cancer control outcomes between these two approaches.

Comprehensive assessment of renal tumour complexity in a large percutaneous cryoablation cohort.

OBJECTIVE: To evaluate the association between renal tumour complexity and outcomes in a large cohort of patients undergoing percutaneous cryoablation (PCA). PATIENTS AND METHODS: Patients with renal tumours treated with PCA were identified using our prospectively maintained ablation registry (2003-2015). Salvage procedures and inherited tumour syndromes were excluded. The associations between R.E.N.A.L. nephrometry score (NS) and risk of complications, renal function impairment, local failure and cancer-specific mortality (CSM) were evaluated using univariate and multivariable logistic, linear and Cox regression models. RESULTS: The cohort included 618 tumours treated during 580 procedures in 565 patients. The median (interquartile range [IQR]) follow-up was 34 (14.66) months. Complications (any grade) during a procedure (n[total] = 87, 15%) were more frequent with higher NS (NS 4-6: 10%; NS 7-9: 14%; NS 10-12: 36%; P < 0.001). Higher NS was independently associated with risk of complications (odds ratio [OR; per 1 point] = 1.3; 95% confidence interval [CI] 1.2-1.5; P < 0.001). Of all the NS components, tumour size was the most strongly associated with complication risk (OR 3.4; 95% CI 2.2-5.2; P < 0.001). The median (IQR) decline in glomerular filtration rate (GFR) from baseline was 9% (0, 22) at last follow-up. Each additional point in NS was associated with a 1.3% (95% CI 0.4-2.1; P = 0.005) greater GFR decline from baseline. NS was not significantly associated with local failure (n [total] = 14, 2%; NS 4-6: 2%; NS 7-9: 3%; NS 10-12: 5%; P = 0.32) or CSM (n [total] = 8, 2%; NS 4-6: 2%; NS 7-9: 3%; NS 10-12: 2%; P = 0.88). CONCLUSION: In high-complexity tumours PCA was associated with a tumour size-driven increased risk of post-procedural complications. Higher NS was associated with a small, clinically minor additional decline in renal function. Risks for local failure and CSM were low, regardless of tumour complexity.

Stereotactic body radiation therapy of liver tumors: post-treatment appearances and evaluation of treatment response: a pictorial review.

Stereotactic body radiation therapy (SBRT) is a noninvasive treatment technique for selected patients with primary liver tumors and liver-confined oligometastatic disease. Recently, SBRT has emerged as an alternative treatment option in non-surgical candidates and in whom percutaneous treatment methods are not possible or contraindicated. The experience with SBRT continues to grow. There are currently no imaging guidelines for assessment of tumor response and follow-up schedule following SBRT. SBRT produces characteristic radiation-induced changes in the treated tumor and surrounding liver parenchyma. Knowledge of these changes is essential in the interpretation of follow-up imaging and assessment of treatment response. In this review, we will describe the CT, MRI, and PET imaging findings following SBRT of both the targeted liver tumor and surrounding hepatic parenchyma.