Radiation segmentectomy of hepatic metastases with Y-90 glass microspheres.

PURPOSE: To evaluate safety and efficacy of radiation segmentectomy (RS) with 90Y glass microspheres in patients with limited metastatic liver disease not amenable to resection or percutaneous ablation. METHODS: Patients with ≤ 3 tumors treated with RS from 6/2015 to 12/2017 were included. Target tumor radiation dose was > 190 Gy based on medical internal radiation dose (MIRD) dosimetry. Tumor response, local tumor progression (LTP), LTP-free survival (LTPFS) and disease progression rate in the treated segment were defined using Choi and RECIST 1.1 criteria. Toxicities were evaluated using modified SIR criteria. RESULTS: Ten patients with 14 tumors underwent 12 RS. Median tumor size was 3 cm (range 1.4-5.6). Median follow-up was 17.8 months (range 1.6-37.3). Response rates per Choi and RECIST 1.1 criteria were 8/8 (100%) and 4/9 (44%), respectively. Overall LTP rate was 3/14 (21%) during the study period. One-, two- and three-year LTPFS was 83%, 83% and 69%, respectively. Median LTPFS was not reached. Disease progression rate in the treated segment was 6/18 (33%). Median overall survival was 41.5 months (IQR 16.7-41.5). Median delivered tumor radiation dose was 293 Gy (range 163-1303). One major complication was recorded in a patient post-Whipple procedure who suffered anaphylactic reaction to prophylactic cefotetan and liver abscess in RS region 6.5 months post-RS. All patients were alive on last follow-up. CONCLUSION: RS of ≤ 3 hepatic segments can safely provide a 2-year local tumor control rate of 83% in selected patients with limited metastatic liver disease and limited treatment options. Optimal dosimetry methodology requires further investigation.

KRAS mutation effects on the 2-[18F]FDG PET uptake of colorectal adenocarcinoma metastases in the liver.

BACKGROUND: Deriving individual tumor genomic characteristics from patient imaging analysis is desirable. We explore the predictive value of 2-[18F]FDG uptake with regard to the KRAS mutational status of colorectal adenocarcinoma liver metastases (CLM). METHODS: 2-[18F]FDG PET/CT images, surgical pathology and molecular diagnostic reports of 37 patients who underwent PET/CT-guided biopsy of CLM were reviewed under an IRB-approved retrospective research protocol. Sixty CLM in 39 interventional PET scans of the 37 patients were segmented using two different auto-segmentation tools implemented in different commercially available software packages. PET standard uptake values (SUV) were corrected for: (1) partial volume effect (PVE) using cold wall-corrected contrast recovery coefficients derived from phantom spheres with variable diameter and (2) variability of arterial tracer supply and variability of uptake time after injection until start of PET scan derived from the tumor-to-blood standard uptake ratio (SUR) approach. The correlations between the KRAS mutational status and the mean, peak and maximum SUV were investigated using Student's t test, Wilcoxon rank sum test with continuity correction, logistic regression and receiver operation characteristic (ROC) analysis. These correlation analyses were also performed for the ratios of the mean, peak and maximum tumor uptake to the mean blood activity concentration at the time of scan: SURMEAN, SURPEAK and SURMAX, respectively. RESULTS: Fifteen patients harbored KRAS missense mutations (KRAS+), while another 3 harbored KRAS gene amplification. For 31 lesions, the mutational status was derived from the PET/CT-guided biopsy. The Student's t test p values for separating KRAS mutant cases decreased after applying PVE correction to all uptake metrics of each lesion and when applying correction for uptake time variability to the SUR metrics. The observed correlations were strongest when both corrections were applied to SURMAX and when the patients harboring gene amplification were grouped with the wild type: p ≤ 0.001; ROC area under the curve = 0.77 and 0.75 for the two different segmentations, respectively, with a mean specificity of 0.69 and sensitivity of 0.85. CONCLUSION: The correlations observed after applying the described corrections show potential for assigning probabilities for the KRAS missense mutation status in CLM using 2-[18F]FDG PET images.

Image-Guided Thermal Ablation for Colorectal Liver Metastases.

Image-guided percutaneous thermal ablation is a widely acceptable local therapy for patients with colorectal liver metastases who are noneligible for surgery or present with recurrence after hepatectomy. The increasing knowledge of factors that affect oncologic outcomes has allowed selected patients with resectable small volume colorectal liver metastases to be treated by thermal ablation with curative intent. The continuous technological evolutions in imaging and image-guidance and the wide implementation of microwave ablation that overcomes most of the limitations of radiofrequency ablation have contributed to this paradigm shift. The importance of patient selection, ablation margin evaluation, and confirmation of complete tumor ablation (A0) are discussed in this article.

Assessment of automated cone-beam CT vessel identification software during transarterial hepatic embolisation: radiation dose, contrast medium volume, processing time, and operator perspectives compared to digital subtraction angiography.

AIM: To evaluate arterial cone-beam computed tomography (A-CBCT) automated analysis software for identification of vessels supplying tumours during transarterial hepatic embolisation (TAE). MATERIALS AND METHODS: This study was approved by the institutional review board, with waiver of consent. Consecutive TAE procedures using arterial mapping software (AMS), and performed between February 2014 and August 2014, were reviewed. Hepatic arteries were imaged using digital subtraction angiography (DSA) as well as A-CBCT processed with AMS. Interventional radiologists reported1 potential embolisation target vessels computed using AMS versus DSA alone,2 modification of the embolisation plan based on AMS, and3 operator confidence related to technical success. Imaging set-up, processing time, radiation dose, and contrast media volume were recorded. RESULTS: Thirty of 34 consecutive procedures were evaluated retrospectively. At least one additional embolisation target vessel was identified using AMS in 13 procedures (43%, 95% confidence interval [CI]: 26-61%) and embolisation plan modified in 11 (37%, 95% CI: 19-54%). Radiologists reported AMS increased operator confidence and reduced the number of DSA acquisitions in 25 (83%, 95% CI: 70-97%) and 15 cases (50%, 95% CI: 32-68%), respectively. The average A-CBCT acquisition and processing time was 4 minutes 53 seconds and 3 minutes 45 seconds, respectively. A-CBCT contributed to 11% of the radiation dose and 18% of the contrast media volume. CONCLUSION: Physicians report increased tumour supplying vessel detection and intraprocedural confidence using AMS during TAE without substantial impact on radiation dose, contrast media volume, and procedure time.

Microwave Ablation in the Management of Colorectal Cancer Pulmonary Metastases.

PURPOSE: To review outcomes following microwave ablation (MWA) of colorectal cancer pulmonary metastases and assess predictors of oncologic outcomes. METHODS: Technical success, primary and secondary technique efficacy rates were evaluated for 50 patients with 90 colorectal cancer pulmonary metastases at immediate, 4-8 weeks post-MWA and subsequent follow-up CT and/or 18F-FDG PET/CT. Local tumor progression (LTP) rate, LTP-free survival (LTPFS), cancer-specific and overall survivals were assessed. Complications were recorded according to SIR classification. RESULTS: Median follow-up was 25.6 months. Median tumor size was 1 cm (0.3-3.2 cm). Technical success, primary and secondary technique efficacy rates were 99, 90 and 92%, respectively. LTP rate was 10%. One-, 2- and 3-year LTPFS were: 93, 86 and 86%, respectively, with median LTPFS not reached. Median overall survival was 58.6 months, and median cancer-specific survival (CSS) was not reached. One-, 2- and 3-year overall and CSS were 94% and 98, 82 and 90%, 61 and 70%, respectively. On univariate analysis, minimal ablation margin (p < 0.001) and tumor size (p = 0.001) predicted LTPFS, with no LTP for minimal margin ≥ 5 mm and/or tumor size < 1 cm. Pleural-based metastases were associated with increased LTP risk (p = 0.002, SHR = 7.7). Pre-MWA CEA level > 10 ng/ml (p = 0.046) and ≥ 3 prior chemotherapy lines predicted decreased CSS (p = 0.02). There was no 90-day death. Major complications rate was 13%. CONCLUSIONS: MWA with minimal ablation margin ≥ 5 mm is essential for local control of colorectal cancer pulmonary metastases. Pleural-based metastases and larger tumor size were associated with higher risk of LTP. CEA level and pre-MWA chemotherapy impacted CSS.

Comparison of CT Fluoroscopy-Guided Manual and CT-Guided Robotic Positioning System for In Vivo Needle Placements in Swine Liver.

PURPOSE: To compare CT fluoroscopy-guided manual and CT-guided robotic positioning system (RPS)-assisted needle placement by experienced IR physicians to targets in swine liver. MATERIALS AND METHODS: Manual and RPS-assisted needle placement was performed by six experienced IR physicians to four 5 mm fiducial seeds placed in swine liver (n = 6). Placement performance was assessed for placement accuracy, procedure time, number of confirmatory scans, needle manipulations, and procedure radiation dose. Intra-modality difference in performance for each physician was assessed using paired t test. Inter-physician performance variation for each modality was analyzed using Kruskal-Wallis test. RESULTS: Paired comparison of manual and RPS-assisted placements to a target by the same physician indicated accuracy outcomes was not statistically different (manual: 4.53 mm; RPS: 4.66 mm; p = 0.41), but manual placement resulted in higher total radiation dose (manual: 1075.77 mGy/cm; RPS: 636.4 mGy/cm; p = 0.03), required more confirmation scans (manual: 6.6; RPS: 1.6; p < 0.0001) and needle manipulations (manual: 4.6; RPS: 0.4; p < 0.0001). Procedure time for RPS was longer than manual placement (manual: 6.12 min; RPS: 9.7 min; p = 0.0003). Comparison of inter-physician performance during manual placement indicated significant differences in the time taken to complete placements (p = 0.008) and number of repositions (p = 0.04) but not in other study measures (p > 0.05). Comparison of inter-physician performance during RPS-assisted placement suggested statistically significant differences in procedure time (p = 0.02) and not in other study measures (p > 0.05). CONCLUSIONS: CT-guided RPS-assisted needle placement reduced radiation dose, number of confirmatory scans, and needle manipulations when compared to manual needle placement by experienced IR physicians, with equivalent accuracy.

Performance of intra-procedural 18-fluorodeoxyglucose PET/CT-guided biopsies for lesions suspected of malignancy but poorly visualized with other modalities.

PURPOSE: We sought to evaluate the safety and the diagnostic success rate of percutaneous biopsies performed under intra-procedural (18)F-deoxyglucose (FDG) positron-emission tomography/computed tomography (PET/CT) guidance for lesions difficult to see with conventional cross-sectional imaging. METHODS: From 2011 to 2013, consecutive clinically indicated percutaneous PET/CT-guided biopsies of 106 masses (mean size, 3.3 cm; range, 0.7-15.9 cm; SD, 2.9 cm) in bones (n = 33), liver (n = 26), soft tissues (n = 18), lung (n = 15) and abdomen (n = 14) were reviewed. The biopsy procedures were performed following injection of a mean of 255 MBq (SD, 74) FDG. Mean maximal standardized uptake value (SUV) of lesions was 8.8 (SD, 6.3). A systematic review of the histopathological results and outcomes was performed. RESULTS: Biopsies were positive for malignancy in 76 cases (71.7%, 76/106) and for benign tissue in 30 cases (28.3%, 30/106). Immediate results were considered adequate for 100 PET/CT biopsies (94.3%, 100/106) requiring no further exploration, and for the six others (5.7%, 6/106) benign diagnoses were confirmed after surgery (n = 4) or follow-up (n = 2). The consequent overall sensitivity and the diagnostic success of biopsy were therefore 100%. No significant differences in terms of detection of malignancy were observed between the different locations. Lesions > 2 cm or with SUV > 4 were not significantly more likely to be malignant. Complications occurred after four biopsies (3.7%, 4/106). CONCLUSION: Intra-procedural PET/CT guidance appears as a safe and effective method and allows high diagnostic success of percutaneous biopsies for metabolically active lesions.

Extrahepatic visualization in the distribution of falciform artery in posttreatment Bremsstrahlung images after radioembolization with (90)Y microspheres.

We report the case of a 39-year-old female with metastatic colorectal cancer. Pretreatment SPECT/CT imaging revealed extrahepatic tracer accumulation along the falciform artery distribution. Prior to the administration of (90)Y microspheres, hepatic arterial anatomy was evaluated angiographically. It was not possible to identify the hepatic falciform artery so that no coil-embolization was performed. The patient tolerated the treatment well with only mild pain around the umbilicus during the procedure that spontaneously abated. As far as we know, this is the first report of Bremsstrahlung SPECT/CT images that has clearly shown that the microspheres accumulation in the anterior abdominal wall corresponds to hepatic falciform artery distribution on CT.

Radiofrequency ablation in the management of liver metastases from breast cancer.

OBJECTIVE: Systemic chemotherapy remains the standard treatment for patients with breast cancer hepatic metastases. Resection of metastases has survival advantages in a small percentage of selected patients. Radiofrequency ablation has been used in small numbers of selected patients. This small series was undertaken to review our experience with radiofrequency ablation in the management of patients with breast cancer hepatic metastases. CONCLUSION: Radiofrequency ablation of breast cancer hepatic metastases is safe and may be used to control hepatic deposits in patients with stable or no extrahepatic disease.

Rates and patterns of recurrence for percutaneous radiofrequency ablation and open wedge resection for solitary colorectal liver metastasis.

INTRODUCTION: The purpose of this study was to compare rates and patterns of disease progression following percutaneous, image-guided radiofrequency ablation (RFA) and nonanatomic wedge resection for solitary colorectal liver metastases. METHODS: We identified 30 patients who underwent nonanatomic wedge resection for solitary liver metastases and 22 patients who underwent percutaneous RFA because of prior major hepatectomy (50%), major medical comorbidities (41%), or relative unresectability (9%). Serial imaging studies were retrospectively reviewed for evidence of local tumor progression. RESULTS: Patients in the RFA group were more likely to have undergone prior liver resection, to have a disease-free interval greater than 1 year, and to have had an abnormal carcinoembryonic antigen (CEA) level before treatment. Two-year local tumor progression-free survival (PFS) was 88% in the Wedge group and 41% in the RFA group. Two patients in the RFA group underwent re-ablation, and two patients underwent resection to improve the 2-year local tumor disease-free survival to 55%. Approximately 30% of patients in each group presented with distant metastasis as a component of their first recurrence. Median overall survival from the time of resection was 80 months in the Wedge group vs 31 months in the RFA group. However, overall survival from the time of treatment of the colorectal primary was not significantly different between the two groups. CONCLUSIONS: Local tumor progression is common after percutaneous RFA. Surgical resection remains the gold standard treatment for patients who are candidates for resection. For patients who are poor candidates for resection, RFA may help to manage local disease, but close follow-up and retreatment are necessary to achieve optimal results.

Upper urinary tract metastases from adenocarcinoma of the colon.

An unusual presentation of colorectal metastasis to the upper urinary tract is reported. The metastasis manifested as a filling defect seen during antegrade pyelography. Cytologic evaluation of aspirated material demonstrated metastatic colonic adenocarcinoma. A dilated collecting system may be caused by intraluminal material including tumor and blood clots. Whenever fixed filling defects are encountered, urine cytology should be sent even in the absence of renal parenchymal involvement by tumor. The cytological evaluation may allow for prompt diagnosis and treatment.

Congenital vascular malformations in the hand and forearm.

PURPOSE: To review a single-center experience in the management of symptomatic congenital vascular malformations of the hand and forearm with special attention to embolotherapy. METHODS: A retrospective chart review was performed to identify patients with vascular malformations referred for arteriography and possible intervention between 1983 and 1998. Arteriography and venography were performed in all patients to differentiate between true high-flow arteriovenous malformations (AVM) and low-flow primary venous malformations (PVM). The clinical and radiological data, procedural results, and follow-up data were retrieved and reviewed. RESULTS: In a 15-year period, 39 patients (22 men; mean age 22.5 years, range 1-51) had symptomatic vascular lesions diagnosed in the forearm and hand: 21 AVMs, 17 PVMs, and one complex lesion with both AVM and PVM. Thirty-four (87%) lesions were treated with immediate technical success achieved in 31 (91%) cases; 5 (13%) lesions were not amenable to percutaneous treatment. There were no major complications, but 3 embolized AVMs had significant residual flow (81.6% technical success on intention to treat basis). Long-term follow-up ranging to 5 years was available in 26 of the 34 treated patients; the mean symptom-free period was 30 months for the AVM patients and 30.5 months for the PVM group, with an average of 1.5 and 1.2 embolization procedures, respectively. CONCLUSIONS: Vascular malformations of the hand and forearm are extremely rare lesions that demand a multidisciplinary approach for optimal diagnosis and management. Microembolotherapy with or without surgery has offered the highest level of safety and success to date.

Retrospective comparison of the Amplatz thrombectomy device with modified pulse-spray pharmacomechanical thrombolysis in the treatment of thrombosed hemodialysis access grafts.

PURPOSE: To retrospectively evaluate the Amplatz thrombectomy device (ATD) in the treatment of thrombosed hemodialysis grafts and compare it with modified pulse-spray pharmacomechanical thrombolysis (PPT). MATERIALS AND METHODS: During a 4-month period, 79 patients presented with 126 episodes of graft occlusion. Percutaneous recanalization was performed by using the ATD (n = 57) or the modified PPT technique (n = 69). Evaluation included the technical success, complications, and primary patency rates. RESULTS: Technical success was achieved in 93% (53 to 57) of the cases treated with the ATD and in 96% (66 of 69) of the cases treated with modified PPT (P = .70). Complications occurred in 6% (four of 69) of modified PPT procedures and 16% (nine of 57) of ATD procedures. This difference was not statistically significant (P = .08); however, there were significantly more local complications in the ATD group (P = .04). The primary patency rates at 30, 90, and 180 days were 65% and 65%, 36% and 50%, and 26% and 33% for modified PPT and ATD, respectively. Survival curves were found not to differ significantly (P = .49). CONCLUSION: The ATD and modified PPT were similarly successful in the recanalization of thrombosed hemodialysis access grafts and achieved comparable primary patency rates. The higher rate of local complications and technical difficulties encountered with use of the 8-F ATD limit its usefulness for this indication.

Endovascular stent placement for angioplasty-induced venous rupture related to the treatment of hemodialysis grafts.

PURPOSE: To assess the use of endovascular stents for treating rupture after percutaneous transluminal angioplasty (PTA) in the maintenance of hemodialysis grafts. MATERIALS AND METHODS: From February 1, 1994, to August 1, 1997, 683 hemodialysis-related angioplasty procedures were performed on 277 patients to treat thrombosed or poorly functioning polytetrafluoroethylene (PTFE) hemodialysis bridge grafts. In each of these procedures, angioplasty of the venous anastomosis or the outflow vein was performed. This study is a retrospective review to analyze uncovered endovascular stents placed to treat ruptures after PTA. RESULTS: Fourteen ruptures were treated with use of an uncovered metal stent. Stent placement was technically successful in 11 of 14 patients, with clinical success in 11 of 14 cases. The primary patencies at 30, 60, 90, and 120 days were calculated by means of Kaplan-Meier life-table analysis; these were 63%, 54%, 46%, and 46%, respectively. The secondary patencies at 60, 120, and 180 days were 85%, 75%, and 75%, respectively. No complications were attributable to stent placement. The results are comparable to those of stents placed for reasons other than rupture, and support the efficacy of their use for this indication. CONCLUSION: Endovascular stent placement is a safe and effective means of salvaging angioplasty-induced rupture that occurs during the treatment of hemodialysis grafts.

Hemodialysis graft mechanical thrombolysis with use of the Amplatz Thrombectomy Device: histopathologic evaluation of extracted myointimal tissue.

PURPOSE: To histopathologically evaluate material extracted from thrombosed hemodialysis access grafts by the Amplatz Thrombectomy Device (ATD). MATERIALS AND METHODS: Thrombosed hemodialysis access grafts were recanalized with use of crossed catheter technique with introduction of the ATD through 8-F sheaths. After removal of the ATD from the introducer sheath, the tip of the device was visually inspected. Discernible tissue in the impeller/housing mechanism was gently extracted with a hemostat and preserved in formalin. Specimens were evaluated histologically with hematoxylin-eosin and smooth muscle immunoperoxidase stains. RESULTS: The ATD was utilized in 18 patients with acutely thrombosed grafts. Sufficient tissue for pathologic evaluation was extracted from 10 devices. Histopathologic analysis yielded findings of fibrotic myointima in all 10 cases with positive smooth muscle stains. CONCLUSIONS: The unexpected, although consistent, finding of intimal and myointimal tissue fragments in the impeller/housing mechanism of the ATD raises questions with respect to the mechanism of tissue extraction and concerns regarding the use of the device in native vessels. Further studies are indicated to determine whether this apparent intimal injury will have a deleterious effect on vessel patency.

Patency of Wallstents placed across the venous anastomosis of hemodialysis grafts after percutaneous recanalization.

PURPOSE: To determine the patency of Wallstents placed across the venous anastomosis of prosthetic bridge grafts after percutaneous graft recanalization. MATERIALS AND METHODS: Wallstents were placed across 26 lesions at the venous anastomosis of polytetrafluoroethylene (PTFE) grafts in 25 patients (11 men, 14 women; age range, 29-83 years; mean age, 65.4 years) after pulse-spray pharmacomechanical thrombolysis. Indications for stent deployment included acute angioplasty failure, rapid restenosis, and vessel perforation. RESULTS: The initial success rate was 100%. The mean primary graft patency rates (+/- standard error) at 3 and 6 months were 34% +/- 9 and 27% +/- 9, respectively. Secondary patency rates were 77% +/- 8 at 3 months, 72% +/- 9 at 6 months, and 50% +/- 10 at 12 months. Eight of the 26 grafts continued to be used for hemodialysis at the end of follow-up. CONCLUSION: After angioplasty failure or vessel perforation, Wallstent placement at the venous anastomosis of recanalized PTFE grafts can salvage hemodialysis access function. The results of this study indicate that the 1-year secondary patency rate of these grafts is 50%, which approaches the reported rates of patency after balloon dilation as part of percutaneous graft recanalization.

Sonographically guided placement of peripherally inserted central venous catheters: review of 355 procedures.

OBJECTIVE: This paper reviews our experience using sonographic guidance in the insertion of peripherally inserted central venous catheters (PICCs). SUBJECTS AND METHODS: Three hundred fifty-five PICCs were placed in 262 patients, 19-92 years old, over a 24-month period using sonographic guidance for the initial venous cannulation. RESULTS: The average number of punctures was 1.2, with an average procedure time of 21 min. Our overall success rate to achieve the initial venous access was 99%. I.v. contrast material was used in only 2% of the cases, after successful initial venous access with sonographic guidance alone, to allow demonstration of anatomic variations or lesions that interfered with the completion of the procedure. Two immediate minor complications occurred. A high margin of safety was provided by avoiding the use of iodinated contrast medium and by visualizing the artery and its anatomic relation to the vein before and during needle placement. CONCLUSION: Sonographic guidance yielded superior three-dimensional localization of the selected vein and its precise anatomic relationship to the artery. Our experience has led us to conclude that sonographically guided placement of PICCs is a fast, safe, efficient, and inexpensive technique and should be the preferred method for PICC placement, especially in patients with no clinically identifiable peripheral vein.