Image-guided core biopsy of 2-cm or smaller renal tumors.

PURPOSE: The purpose of this study was to retrospectively evaluate diagnostic yield, risk factors for diagnostic failure, and safety of image-guided core biopsy of renal tumors≤2cm. MATERIALS AND METHODS: Eighty-four biopsies of 84 renal tumors (mean size, 1.5±0.4[SD] cm; range, 0.6-2.0cm) from 84 patients (53 men, 31 women; mean age, 61.7±12.7 [SD] years; age range, 34-87 years) were included. All adverse events (AEs) were evaluated based on the CIRSE classification. The 84 procedures were classified as diagnostic or nondiagnostic. Multiple variables related to the patients, tumors, and procedures were assessed to identify variables associated with diagnostic failure. RESULTS: All 84 biopsies (100%) were technically successful, defined as penetration of the target and acquisition of some specimens. Eighty (80/84; 95.2%) biopsy procedures were diagnostic and four (4/84; 4.8%) procedures were nondiagnostic. Among 80 diagnosed renal tumors, 71/80 (88.8%) tumors were malignant (49 clear cell renal cell carcinomas [RCCs], 14 papillary RCCs, 3 chromophobe RCCs, 3 metastatic renal cancers, 1 lymphoma, and 1 unclassified RCC) and 9/80 (11.2%) lesions were benign (5 angiomyolipomas, 3 oncocytomas, and 1 inflammatory lesion). No significant differences existed in any variables between the two groups. A total of 57 (57/84; 67.9%) procedures resulted in 56 Grade 1, 2 Grade 2, and 1 Grade 3 AEs. CONCLUSION: Image-guided biopsy of renal tumors≤2cm is safe and has a high diagnostic yield.

Embolization using hydrogel-coated coils for pulmonary arteriovenous malformations.

PURPOSE: To prospectively evaluate the efficacy and safety of embolization using hydrogel-coated coils for the treatment of pulmonary arteriovenous malformations (PAVMs). MATERIALS AND METHODS: The outcomes of 21 PAVMs in 19 patients (3 men and 16 women; mean age, 58.8±15.2 [SD] years; age range 14-78 years) treated by venous sac embolization (VSE) with additional feeding artery embolization were prospectively evaluated. For VSE, using one or more 0.018-inch hydrogel-coated coils was mandatory. Recanalization and/or reperfusion were evaluated by pulmonary arteriography 1 year after embolization. RESULTS: The mean feeding artery and venous sac sizes were 4.0mm and 8.5mm, respectively. Embolization was successfully completed in 20/21 PAVMs, yielding a technical success rate of 95%. The feeding artery was also embolized in 17/20 successful PAVMs (85%). A technical failure occurred in one PAVM, where embolization was abandoned because of migration of one bare coil to the left ventricle. The mean numbers of hydrogel-coated coils and bare platinum detachable coils used for VSE were 3.3±2.1 (SD) (range, 1-8) and 4.4±3.9 (SD) (range, 1-17), respectively. The mean percentages of hydrogel-coated coils in number, length, and estimated volume were 42.9%, 33.3%, and 72.7% respectively. One patient with one PAVM was lost to follow-up after 3 months. Neither recanalization nor reperfusion was noted in the remaining 19 PAVMs (success rate, 19/19 [100%]). One grade 4 (coil migration) adverse event occurred, and it was treated without any sequelae. CONCLUSION: VSE using hydrogel-coated coils with additional feeding artery embolization is a safe and effective treatment for PAVM.

Percutaneous thermal ablation for renal cell carcinoma in patients with Birt-Hogg-Dubé syndrome.

PURPOSE: The purpose of this study was to analyze the outcome of patients with Birt-Hogg-Dubé (BHD) syndrome who underwent percutaneous thermal ablation of renal cell carcinoma (RCC). MATERIALS AND METHODS: Six patients with genetically proven BHD syndrome who underwent one or more sessions of percutaneous thermal ablation for the treatment of RCC were included. There were 4 men and 2 women, with a mean age of 57.3±7.5 [SD] years (range: 44-67years). A total of 29 RCCs (1-16 tumors per patient) were treated during 20 thermal ablation sessions (7 with radiofrequency ablation and 13 with cryoablation). Outcomes of thermal ablation therapy were assessed, including technical success, adverse events, local tumor progression, development of metastases, survival after thermal ablation, and changes in renal function. RESULTS: Technical success was achieved in all ablation sessions (success rate, 100%). No grade 4 or 5 adverse events were observed. All patients were alive with no distant metastasis during a median follow-up period of 54months (range: 6-173months). No local tumor progression was found. The mean decrease in estimated glomerular filtration rate during follow-up was 10.7mL/min/1.73m2. No patients required dialysis or renal transplantation. CONCLUSION: Radiofrequency ablation and cryoablation show promising results for the treatment of RCCs associated with BHD syndrome. Percutaneous thermal ablation may be a useful treatment option for this rare hereditary condition.

Short hookwire placement under imaging guidance before thoracic surgery: A review.

During video-assisted thoracic surgery (VATS), localization is sometimes needed to detect a target lesion that is too small and/or too far from the pleura. In 1995, Kanazawa et al. developed short hookwire and suture system. Since then, this system has been placed often for selected targets before VATS in Japan. This short hookwire and suture system is a representative preoperative localization method and the placement procedure is well-established. Its placement success rates are very high (range: 97.6%-99.6%), and dislodgement of this short hookwire rarely occurs with an incidence of 0.4%-2.5%. The most common complication of short hookwire placement is pneumothorax (incidence: 32.1%-68.1%), followed by pulmonary hemorrhage (incidence: 8.9%-41.6%). Complications are frequent; however, most complications are minor and asymptomatic.

CT fluoroscopy-guided core needle biopsy of anterior mediastinal masses.

OBJECTIVE: To retrospectively evaluate the safety, diagnostic yield, and risk factors of diagnostic failure of computed tomography (CT) fluoroscopy-guided biopsies of anterior mediastinal masses. MATERIALS AND METHODS: Biopsy procedures and results of anterior mediastinal masses in 71 patients (32 women/39 men; mean [±standard deviation] age, 53.8±20.0years; range, 14-88years) were analyzed. Final diagnoses were based on surgical outcomes, imaging findings, or clinical follow-up findings. The biopsy results were compared with the final diagnosis, and the biopsy procedures grouped by pathologic findings into diagnostic success and failure groups. Multiple putative risk factors for diagnostic failure were then assessed. RESULTS: Seventy-one biopsies (71 masses; mean size, 67.5±27.3mm; range 8.6-128.2mm) were analyzed. We identified 17 grade 1 and one grade 2 adverse events (25.4% overall) according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Sixty-nine biopsies (97.2%) provided samples fit for pathologic analysis. Diagnostic failure was found for eight (11.3%) masses; the 63 masses diagnosed successfully included thymic carcinoma (n=17), lung cancer (n=14), thymoma (n=12), malignant lymphoma (n=11), germ cell tumor (n=3), and others (n=6). Using a thinner needle (i.e., a 20-gauge needle) was the sole significant risk factor for diagnostic failure (P=0.039). CONCLUSION: CT fluoroscopy-guided biopsy of anterior mediastinal masses was safe and had a high diagnostic yield; however, using a thinner biopsy needle significantly increased the risk of a failed diagnosis.

Radiofrequency ablation of pulmonary tumors near the diaphragm.

PURPOSE: To retrospectively evaluate the feasibility, safety, and efficacy of radiofrequency ablation (RFA) of lung tumors located near the diaphragm. MATERIALS AND METHODS: A total of 26 patients (15 men, 11 women; mean age, 61.5 years±13.0 [SD]) with a total of 29 lung tumors near the diaphragm (i.e., distance<10mm) were included. Mean tumor diameter was 11.0mm±5.3 (SD) (range, 2-23mm). Efficacy of RFA, number of adverse events and number of adverse events with a grade≥3, based on the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0, were compared between patients with lung tumors near the diaphragm and a control group of patients with more distally located lung tumors (i.e., distance≥10mm). RESULTS: RFA was technically feasible for all tumors near the diaphragm. Four grade 3 adverse events (1 pneumothorax requiring pleurodesis and 3 phrenic nerve injuries) were observed. No grade≥4 adverse events were reported. The median follow-up period for tumors near the diaphragm was 18.3 months. Local progression was observed 3.3 months after RFA in 1 tumor. The technique efficacy rates were 96.2% at 1 year and 96.2% at 2 years and were not different, from those observed in control subjects (186 tumors; P=0.839). Shoulder pain (P<0.001) and grade 1 pleural effusion (P<0.001) were more frequently observed in patients with lung tumor near the diaphragm. The rates of grade≥3 adverse events did not significantly differ between tumors near the diaphragm (4/26 sessions) and the controls (7/133 sessions) (P=0.083). CONCLUSION: RFA is a feasible and effective therapeutic option for lung tumors located near the diaphragm. However, it conveys a higher rate of shoulder pain and asymptomatic pleural effusion by comparison with more distant lung tumors.

Simultaneous biopsy and radiofrequency ablation of T1a renal cell carcinoma.

OBJECTIVE: The goal of this study was to retrospectively evaluate the outcome, including feasibility, safety, diagnostic yield, and factors affecting the success of computed tomography fluoroscopy-guided biopsy when performed during the same procedure than radiofrequency ablation (RFA) in renal tumors strongly suspected of being T1a renal cell carcinoma (RCC). MATERIALS AND METHODS: Nineteen patients (13 men, 6 women; mean age, 66.7 years) with a total of 19 suspected renal tumors (mean diameter, 1.8cm) underwent computed tomography fluoroscopy-guided biopsy during (n=6) or immediately after (n=13) RFA. All patients were strongly suspected of having RCC on the basis of patient's medical histories and/or the results of imaging investigations. All procedures were divided into diagnostic and non-diagnostic biopsies. Various variables were compared between the 2 groups using univariate analysis. RESULTS: In all tumors, biopsy procedures were technically feasible. No major complications were observed, except for 8 minor post-procedural bleedings. All but one tumor was completely ablated. Local recurrence in the ablation zone as well as tumor seeding in retroperitoneal fat occurred in 1 patient 8.5months after the procedure and were successfully treated with further percutaneous cryoablation. Thirteen tumors were diagnosed as RCC, whereas 6 were ultimately found to contain normal renal tissue (n=5) or connective tissue (n=1). Univariate analysis revealed that none of the variables were significantly different between the diagnostic and non-diagnostic biopsies. CONCLUSION: The performance of renal tumor biopsy and RFA in the same session is feasible and safe. Although pre-treatment pathological diagnosis would be generally desirable, simultaneous biopsy with RFA can be an option for the patients who are not amenable to pre-treatment biopsy.