Radiofrequency ablation in patients with interstitial lung disease and lung neoplasm: a retrospective multicenter study.

PURPOSE: To retrospectively investigate the safety and efficacy of percutaneous radiofrequency ablation (RFA) by analyzing results in patients with lung neoplasm accompanied by interstitial lung disease (ILD) on computed tomography (CT) in a multicenter study. MATERIALS & METHODS: Patients with lung neoplasm accompanied by ILD who underwent RFA between April 2002 and October 2017 at seven institutions were investigated. Technical success rate, and local tumor progression (LTP) of ablated tumors were evaluated. Adverse events including acute exacerbation of ILD were also evaluated. Univariate analyses were performed to identify factors associated with acute exacerbation. RESULTS: Forty-nine patients with 64 lung neoplasm (mean diameter, 22.6 mm; range, 4-58 mm) treated in 66 sessions were included. Usual interstitial pneumonia (UIP) pattern on CT was identified in 23 patients (47%). All patients underwent successful RFA. Acute exacerbations were seen in 5 sessions (8%: 7% with UIP pattern, 8% without) in 5 patients, all occurring on or after 8 days (median, 12 days; range, 8-30 days). Three of those 5 patients died of acute exacerbation. Treatment resulted in mortality after 5% of sessions, representing 6% of patients. Pleural effusion and fever ≥38°C after RFA were identified by univariate analysis (p = 0.0012, p = 0.02, respectively) as significant risk factors for acute exacerbation. The cumulative LTP rate was 43% at 1 year. CONCLUSIONS: RFA appears feasible for patients with lung neoplasm complicated by ILD. Acute exacerbation occurred in 8% of patients with symptoms occurring more than 8 days post-ablation and was associated with a 45% mortality rate.

Ablation of Kidney Tumors in Patients with Substantial Kidney Impairment: Current Status.

PURPOSE OF REVIEW: To review the current status of kidney tumor ablation in patients with substantial kidney impairment. RECENT FINDINGS: Few reports of kidney tumor ablation in such patients have recently been published. The reported prevalence of patients with stage 4 or 5 chronic kidney disease (CKD) among patients undergoing ablation is 2.0%-10%. In patients with stage 4 or 5 CKD, local tumor control rates were 88%-100%. The effect of ablation on CKD stage is unclear, and the observed deteriorations in kidney function are consistent with both the effect of cryoablation and the natural course of advanced CKD. According to guidelines, active surveillance may be selected. The goals of treatment are complete tumor removal and maintenance of kidney function, both of which can be met by ablation. Given the limited treatment options, ablation may play a pivotal role in the management of patients with advanced CKD.

Robotic systems in interventional oncology: a narrative review of the current status.

Interventional oncology offers minimally invasive treatments for malignant tumors for curative and palliative purposes based on the percutaneous insertion of needles or catheters into the target location under image guidance. Robotic systems have been gaining increasing attention as tools that provide potential advantages for image-guided interventions. Among the robotic systems developed for intervention, those relevant to the oncology field are mainly those for guiding or driving the needles in non-vascular interventional procedures such as biopsy and tumor ablation. Needle-guiding robots support planning the needle path and align the needle robotically according to the planned trajectory, which is combined with subsequent manual needle insertion by the physician through the needle guide. Needle-driving robots can advance the needle robotically after determining its orientation. Although a wide variety of robotic systems have been developed, only a limited number of these systems have reached the clinical phase or commercialization thus far. The results of previous studies suggest that such interventional robots have the potential to increase the accuracy of needle placement, facilitate out-of-plane needle insertion, decrease the learning curve, and reduce radiation exposure. On the other hand, increased complexity and costs may be a concern when using robotic systems compared with conventional manual procedures. Further data should be collected to comprehensively assess the value of robotic systems in interventional oncology.

Regression of Necrotic Lesions after Methotrexate Withdrawal in Patients with Methotrexate-Associated Lymphoproliferative Disorders: A Retrospective CT Study.

This retrospective study investigated whether necrotic lesions detected on a computed tomography (CT) scan are more regressive than non-necrotic lesions after methotrexate withdrawal in patients pathologically diagnosed with methotrexate-associated lymphoproliferative disorders (MTX-LPD). In total, 89 lesions extracted from 24 patients on CT scans were included in the analysis. All patients had been evaluated for the presence of necrosis within lesions via CT scan upon first suspicion of MTX-LPD (baseline CT scan). The percentage lesion size reduction between the baseline and initial follow-up CT scan was calculated. The association between necrosis within lesions and size changes was estimated via linear regression analyses using both crude and adjusted models. Necrosis was significantly more common in extranodal lesions (27 out of 30 lesions, 90%) than in nodal lesions (9 out of 59 lesions, 15%, p<0.001). In the crude model, the regression of necrotic lesions was 58.5% greater than that of non-necrotic lesions; the difference was statistically significant (p<0.001). Additionally, the longest diameter of necrotic lesions at the baseline CT scan was significantly greater than that of non-necrotic lesions (p<0.001). Based on the adjusted model, necrotic lesions showed 49.3% greater regression than non-necrotic lesions (p=0.017). Necrosis detected on a CT scan was found to be an independent predictor of regression after MTX withdrawal in patients with MTX-LPD.

Photon-Counting Detector CT: Potential for 75% Reduction in Contrast Medium Amount: A Phantom Study.

This study aimed to evaluate the potential reduction in contrast medium utilization using photon-counting detector computed tomography (PCD-CT). One PCD-CT scan (CT1) and three conventional (non-PCD-CT) CT scans (CT2-CT4) were performed using a multi-energy CT phantom that contained eight rods with different iodine concentrations (0.2, 0.5, 1, 2, 5, 10, 15, and 20 mg/ml). The CT values of the seven groups (CT1 for 40, 50, 60, and 70 keV; and CT2-4) were measured. Noise and contrast-to-noise ratio (CNR) were assessed for the eight rods at various iodine concentrations. CT2 and CT1 (40 keV) respectively required 20 mg/ml and 5 mg/ml of iodine, indicating that a comparable contrast effect could be obtained with approximately one-fourth of the contrast medium amount. The standard deviation values increased at lower energy levels irrespective of the iodine concentration. The CNR exhibited a decreasing trend with lower iodine concentrations, while it remained relatively stable across all iodine levels (40-70 keV). This study demonstrated that virtual monochromatic 40 keV images offer a similar contrast effect with a reduced contrast medium amount when compared to conventional CT systems at 120 kV.

Impact of the neutrophil-to-lymphocyte ratio on patients with locally advanced non-small cell lung cancer who suffer radiation pneumonitis during the course of induction chemoradiotherapy followed by surgery.

PURPOSE: Radiation pneumonitis (RP) is an obstacle for patients after surgery following induction chemoradiotherapy for locally advanced non-small cell lung cancer (LA-NSCLC). We performed a comparative analysis of the association between clinicopathological factors, including the neutrophil-to-lymphocyte ratio (NLR) and prognosis, in LA-NSCLC patients with or without RP during induction chemoradiotherapy followed by surgery. METHODS: The subjects of this analysis were 168 patients undergoing trimodality therapy for LA-NSCLC between January, 1999 and May, 2019. Patients were divided into two groups: the RP group (n = 41) and the non-RP group (n = 127). We compared the clinicopathological factors including the NLR between the groups and analyzed the association between the NLR and prognosis. RESULTS: The RP group had more patients with tumors located in the lower lobe, more bilobar resections, shorter operative times, no implementation of postoperative adjuvant chemotherapy, and a higher postoperative NLR than the non-RP group. There were no significant differences in serious postoperative complications and the prognosis. Patients with a low postoperative NLR had a significantly better prognosis in the non-RP group, and a trend toward a better prognosis even in the RP group. CONCLUSION: Postoperative NLR may be a useful prognostic factor, even for patients who suffer RP after trimodality therapy for LA-NSCLC.

Arterial embolization via retrograde approach using steerable microcatheter and triaxial system.

We report a case of postoperative pseudoaneurysm, successfully treated with selective arterial embolization, using a steerable microcatheter and triaxial system via retrograde approach. A pseudoaneurysm was detected in the dorsal pancreatic artery, a severely narrow and steeply inverted branch of the superior mesenteric artery, making microcatheter insertion via the antegrade approach challenging. However, a steerable microcatheter was advanced beyond the orifice and the tip was reversed, changing the route to retrograde allowing for easy insertion of the microguidewire. Subsequently, a small microcatheter was advanced beyond the pseudoaneurysm into the dorsal pancreatic artery, and arterial embolization was successfully completed without complications.

Is cryoablation a valid option for renal cell carcinomas in direct contact with critical organs?

PURPOSE: This study aimed to assess the outcomes of percutaneous cryoablation (PCA) for renal cell carcinomas (RCCs) contacting critical organs without intervening fat tissue. MATERIAL AND METHODS: Twenty-three patients with 24 RCCs (mean size, 28.8 mm) contacting critical organs on preprocedural images were included. The organ displacement techniques, technical success, efficacy, and adverse events per Clavien-Dindo classification were retrospectively reviewed. RESULTS: The organs contacting the RCCs included the colon (n = 16), pancreas (n = 3), duodenum (n = 3), small intestine (n = 1), and stomach (n = 1). In all procedures, hydrodissection was conducted, and probe traction was additionally utilized in one to displace organs. Two procedures were terminated with an insufficient ice-ball margin (<6 mm) due to recurring proximity of the colon or thermal sink effect by renal hilar vessels, yielding a technical success rate of 91.6% (22/24). No severe adverse events were noted. All patients were alive without any metastases during a median follow-up of 34.4 months. The primary and secondary technical efficacy rates were 91.6% (22/24) and 95.8% (23/24) of tumors, respectively. CONCLUSION: PCA can be a valid option for RCCs contacting critical organs with a good safety profile and sufficient technical efficacy.

Navicular Bone Fracture after Radiofrequency Ablation in a Patient with Osteoid Osteoma.

Osteoid osteoma (OO) is a benign bone tumor that presents with nocturnal pain. Computed tomography (CT)- guided radiofrequency ablation (RFA) has been widely performed for OO, and major adverse events post-RFA are rare. We report a case of OO in the left navicular bone of a 15-year-old male. He underwent RFA for OO, and the pain improved temporarily. At the 1-month follow-up, the patient complained of left foot pain, and a CT examination revealed a fracture of the ablated navicular bone. Fractures are rare but must be taken into account after bone RFA.

Complications of Percutaneous Cryoablation for Renal Tumors and Methods for Avoiding Them.

Percutaneous cryoablation of renal tumors is widely used because of its high efficacy and safety. This high safety can be attributed, at least in part, to the visibility of the ablated area as an "ice ball". This therapy has fewer complications (incidence, 0-7.2%) and is less invasive than surgery. Minor bleeding is inevitable in most kidney-related procedures, and indeed the most common complication of this therapy is bleeding (hematoma and hematuria). However, patients require treatment such as transfusion or transarterial embolization in only 0-4% of bleeding cases. Various other complications such as ureteral or collecting system injury, bowel injury, nerve injury, skin injury, infection, pneumothorax, and tract seeding also occur, but they are usually minor and asymptomatic. However, operators should know and avoid the various complications associated with this therapy. This study aimed to summarize the complications of percutaneous cryoablation for renal tumors and provide some techniques for achieving safe procedures.

A Case of Migration of a Hydrogel Spacer for Radiotherapy into the Pulmonary Artery.

A 67-year-old man was referred to our hospital for the diagnosis and treatment of prostate cancer. Multidisciplinary discussion led to intensity-modulated radiotherapy preceded by hormone therapy. Before radiotherapy, a biodegradable hydrogel spacer (HS) was placed between the prostate and rectum to reduce radiation injury risk. Three weeks postplacement, pelvic magnetic resonance imaging revealed HS migration into the pelvic vein. Subsequent whole-body contrast-enhanced computed tomography (CECT) revealed HS migration into the pulmonary artery. The patient showed no symptoms or clinical signs. Radiotherapy was completed uneventfully. Complete absorption of the migrated HS was confirmed using CECT images 5 months postplacement.

Omental Abscess after Laparoscopic Proximal Gastrectomy Successfully Treated with Percutaneous Drainage.

We report the case details of a 65-year-old Japanese man with an omental abscess that was discovered 43 days after he underwent a laparoscopic proximal gastrectomy for gastric cancer. His chief complaint was mild abdominal pain that had persisted for several days. The abscess was diagnosed as a rare postoperative complication. We hesitated to perform a reoperation given the invasiveness of general anesthesia and surgery, plus the possibility of postoperative adhesions and because the patient's general condition was stable and he had only mild abdominal pain. Percutaneous drainage using a 10.2-F catheter was performed with the patient under conscious sedation and computed tomography-fluoroscopy guidance, with no complications. After the procedure, the size of the abscess cavity was remarkably reduced, and 23 days later the catheter was withdrawn.

Outcomes of solitary postoperative recurrence of esophageal squamous cell carcinoma diagnosed with FDG-PET/CT and treated with definitive radiation therapy.

BACKGROUND: Surgical resection of esophageal cancer is frequently performed to achieve a complete cure. However, the postoperative recurrence rate is 36.8-42.5%, leading to poor prognosis. Radiation therapy has been used to treat recurrences; solitary recurrence has been proposed as a prognostic factor for radiation therapy, though its significance is unclear. 18F-fluorodeoxyglucose positron emission tomography is a highly accurate diagnostic modality for esophageal cancer. This retrospective study aimed to analyze the outcomes of solitary postoperative recurrences of esophageal squamous cell carcinoma diagnosed with 18F-fluorodeoxyglucose positron emission tomography and treated with definitive radiation therapy. METHODS: We examined 27 patients who underwent definitive radiation therapy for single or multiple postoperative recurrences of esophageal squamous cell carcinoma between May 2015 and April 2021. 18F-fluorodeoxyglucose positron emission tomography/computed tomography was performed within 3 months before the commencement of radiation therapy. Kaplan-Meier, univariate, and multivariate analyses were performed to examine the overall survival and identify potential prognostic factors. RESULTS: The 1-, 2-, and 3-year overall survival rates were 85.2%, 62.6%, and 47.3%, respectively, and solitary recurrence was the only significant factor associated with overall survival (P = 0.003). The 1-, 2-, and 3-year overall survival rates in patients with solitary recurrence were 91.7%, 80.2%, and 80.2%, respectively, and in patients with multiple recurrences they were 80.0%, 50.3%, and 25.1%, respectively. Multivariate analysis also showed solitary recurrence as a significant factor for overall survival. CONCLUSIONS: When diagnosed with 18F-fluorodeoxyglucose positron emission tomography/computed tomography, solitary recurrence appears to have a more favorable prognosis than multiple recurrences.

Percutaneous cryoablation combined with prior transcatheter arterial embolization for renal cell carcinomas of 3 cm or larger: a prospective study.

BACKGROUND: We prospectively evaluated the safety and efficacy of percutaneous cryoablation combined with transcatheter renal arterial embolization for the treatment of tumors ≥ 3 cm in diameter. METHODS: We included patients aged ≥ 20 years with histologically proven renal cell carcinoma with a tumor diameter ≥ 3 cm who were inoperable or refused surgery. Prior to ablation, transcatheter arterial embolization was performed using a mixture of absolute ethanol and iodized oil. All cryoablation procedures were performed percutaneously under computed tomography fluoroscopy guidance. The primary endpoint was safety, which was evaluated for adverse events using CTCAE version 4.0. The secondary endpoint was survival; overall survival, progression-free survival, and cancer-specific survival were calculated. RESULTS: From October 2013 to March 2016, 19 patients (mean age, 75 ± 13 years; 5 women, 14 men) were prospectively enrolled. The mean tumor diameter was 3.9 ± 0.7 (range 3.1-5.3) cm. Four grade 3 hematologic adverse events occurred, while no symptomatic grade ≥ 3 events occurred. The median follow-up period was 68 (range 52-84) months. During the follow-up period, two patients developed local tumor progression at 3 and 42 months after the initial ablative procedure; no patient showed distant metastasis. Two patients died from causes other than RCC. Overall survival, progression-free survival, and cause-specific survival were 100%, 95%, and 100% at 3 years, and 95%, 84%, and 100% at 5 years, respectively. CONCLUSION: Percutaneous cryoablation combined with prior TAE for the treatment of tumors ≥ 3 cm in diameter was safe and achieved favorable survival.

A Rare Case of Idiopathic Spinal Cord Herniation Treated by DuraGen® Collagen Matrix Graft.

We report a rare case of idiopathic spinal cord herniation (ISCH) with a history of cerebrospinal fluid (CSF) leakage. ISCH is a protrusion of the spinal cord through a dural defect. Thin constructive interference in steady-state (CISS) images clearly demonstrated the herniated cord in the present case. The myelopathy worsened and the patient underwent surgery for reduction of herniated spinal cord; the dural defect was filled by placing collagen matrix graft (DuraGen®) between the inner and outer dural layers. The patient's symptoms have improved without relapse for 8 months since surgery. This method may be a good surgical option for cases of spinal cord herniation.

In Vivo Microwave Ablation of Normal Swine Lung at High-power, Short-duration Settings.

To evaluate the volume and heat-sink effects of microwave ablation (MWA) in the ablation zone of the normal swine lung. MWA at 100 W was performed for 1, 2, and 3 min in 7, 5, and 5 lung zones, respectively. We assessed the histopathology in the ablation zones and other outcome measures: namely, length of the longest long and short axes, sphericity, ellipsoid area, and ellipsoid volume. The mean long- and short-axis diameters were 22.0 and 14.1 mm in the 1-min ablation zone, 27.6 and 20.2 mm in the 2-min ablation zone; and 29.2 and 21.2 mm in the 3-min ablation zone, respectively. All measures, except sphericity, were significantly less with 1-min ablation than with either 2- or 3-min ablation. There were no significant differences between the 2- and 3-min ablation zones, but all measures except sphericity were larger with 3-min ablation. Although there were no blood vessels that resulted in a heat-sink effect within the ablation zones, the presence of bronchi nearby in 5 lung ablation zones resulted in reduced ablation size. In high-power, short-duration MWA, the lung ablation volume was affected by ablation time. Some ablations showed that a heat-sink effect by a neighboring bronchus might occur.

Sarcopenia is related to poor prognosis in patients after trimodality therapy for locally advanced non-small cell lung cancer.

BACKGROUND: The association between sarcopenia and prognosis in patients with locally advanced non-small cell lung cancer (NSCLC) undergoing trimodality therapy, consisting of preoperative concurrent chemoradiotherapy and surgery, has not been reported. Therefore, we aimed to investigate the association of sarcopenia and fat mass with prognosis after trimodality therapy. METHODS: To assess sarcopenia, the psoas muscle mass was measured. Using computed tomography data, including third lumbar vertebra level images, psoas muscle mass and visceral and subcutaneous fat mass were measured. Additionally, body mass indices, and visceral/subcutaneous fat ratio, obtained by dividing the visceral fat index by the subcutaneous fat index, were calculated. We investigated the relationship between these parameters and overall survival. RESULTS: Ninety-nine eligible patients were included. In the univariate analysis, age, clinical stage, tumor location, psoas muscle index, and visceral/subcutaneous fat ratio were significant prognostic factors for overall survival (P = 0.008, P = 0.04, P = 0.04, P = 0.02, and P = 0.02, respectively). In the multivariate analysis, age and psoas muscle index were significant prognostic factors for overall survival (P = 0.01 and P = 0.03, respectively). The 5-year overall survival rates for the high and low psoas muscle index groups were 79.6% [95% confidence interval (CI), 67.1-94.5%] and 66.2% (95% CI, 54.1-81.1%), respectively; whereas, the 10-year overall survival rates were 61.9% (95% CI, 42.0-91.4%) and 25.3% (95% CI, 8.6-74.2%), respectively. CONCLUSION: Sarcopenia was related to poor overall survival in patients with locally advanced NSCLC undergoing trimodality therapy. Assessment of body composition prior to treatment may provide important information for formulating rational therapeutic strategies.

Oncologic outcomes and safety of percutaneous cryoablation for biopsy-proven renal cell carcinoma up to 4 cm in diameter: a prospective observational study.

BACKGROUND: Percutaneous cryoablation is widely used for the treatment of renal cell carcinoma. We prospectively evaluated the oncologic outcomes and safety of percutaneous cryoablation for the treatment of tumors ≤ 4 cm in diameter. METHODS: We included patients aged ≥ 20 years, who had histologically proven renal cell carcinoma, tumor diameter ≤ 4 cm, a performance status of ≤ 1, acceptable laboratory parameters, were inoperable or refused to undergo surgery, and had signed a written informed consent. The primary endpoint was the cause-specific survival rate. The secondary endpoints were overall and progression-free survival, and adverse event frequency and grade. All procedures were percutaneously performed under computed tomography fluoroscopy guidance. RESULTS: From October 2013 to October 2015, 33 patients (mean age: 68 ± 14 years; sex: six women, 27 men) were enrolled. The mean tumor diameter was 2.1 ± 0.6 (range 1.0-3.4) cm. The median follow-up period was 60.1 (range 18.4-76.6) months. One patient died of non-renal cell carcinoma-related disease 46 months after percutaneous cryoablation. The cause-specific and overall survival rates were 100% and 96.8% at 3 years, and 100% and 96.8% at 5 years, respectively. There was no local tumor progression or distant metastasis. The incidence of severe urological (urinary fistula and perinephric infection) and non-urological adverse events (increased creatine kinase and skin ulceration) was 6% each. CONCLUSION: Percutaneous cryoablation for renal cell carcinoma ≤ 4 cm in diameter achieved good tumor control with a low complication frequency.

Clinical Outcome of Palliative Concurrent Chemoradiotherapy with Cisplatin/Docetaxel for Stage III Non-small Cell Lung Cancer.

Palliative concurrent chemoradiotherapy (CCRT) is often administered to patients with stage III non-small cell lung cancer (NSCLC). We investigated the clinical outcomes of patients receiving palliative CCRT for NSCLC. Data of patients with NSCLC who underwent palliative CCRT (n=16), preoperative CCRT plus surgery (n=97), or definitive CCRT (n=48) were evaluated. In all groups, the concurrent chemotherapy regimens consisted of cisplatin and docetaxel. Rates of local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS), overall survival (OS), and prognosis were compared. The 2-year rates of LC, DMFS, PFS, and OS in 16 patients who underwent palliative CCRT were 44.4%, 12.5%, 12.5%, and 18.8%, respectively. Univariate analysis showed that palliative CCRT was associated with poor LC (p<0.001), DMFS (p<0.001), PFS (p<0.001), and OS (p<0.001) outcomes in patients who completed CCRT as a preoperative treatment and poor LC (p=0.01), DMFS (p=0.003), PFS (p=0.04), and OS (p=0.004) outcomes in patients who were considered for definitive CCRT. Although there were some long-term survivors, the clinical outcomes of palliative CCRT were significantly inferior to those of the ideal treatments. Therefore, careful determination of the appropriate treatment indications and further studies are warranted.

Needle Tract Ablation in Liver Tissue Using a Cryoprobe Combined with an Electrosurgical Device: Influence of ex vivo and in vivo Animal Models.

To assess the feasibility of needle tract ablation in liver tissue in ex vivo and in vivo animal models using a cryo-probe and electrosurgical device. The experimental device is made by inserting a cryoprobe through an intro-ducer sheath for insulation, with 2-cm of probe tip projecting out. A beagle liver was punctured by the device, and electric current was applied at 30-W with the electrosurgical knife touching the non-insulated device base. The discolored area of cut surface along the device was evaluated in 5 application-time groups (5 , 10 , 15 , 20, or 25 seconds). An ex vivo experiment was performed to determine an ablation algorithm with an appropriate application time by comparison with radiofrequency ablation (RFA) results. Thereafter, an in vivo experiment was performed to verify the algorithm's feasibility. In the ex vivo model, the cut surface demonstrated different amounts of discolored area according to the application time. The total discolored area in the 20-seconds group was similar to that by RFA. In the in vivo model, the liver did not bleed, the total discolored area was similar to that ex vivo, and coagulation necrosis was confirmed by photomicrograph. Needle tract ablation can be per-formed using the experimental device and electrosurgical device.