Survival of Patients with Colorectal Liver Metastases after Transarterial Chemoembolization Using Irinotecan-Eluting Microspheres: A Single-Center Retrospective Analysis Comparing RECIST 1.1 and Choi Criteria.

PURPOSE: To evaluate the factors that affected overall survival and hepatic progression-free survival using the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and Choi criteria in patients with colorectal liver metastases treated with transarterial chemoembolization (TACE) using irinotecan-eluting microspheres (IEMs) who failed at least 1 line of systemic chemotherapy. MATERIALS AND METHODS: A single-institution retrospective analysis was performed including patients with unresectable liver metastases from a colorectal primary malignancy and treated with IEM-TACE. Radiologic hepatic progression-free survival was measured using the RECIST 1.1 and Choi criteria. RESULTS: The median patient age was 61.5 years, with 80 (67%) men. A total of 328 IEM-TACE procedures were performed during the study period. One hundred eighteen patients who failed at least 1 line of systemic chemotherapy before TACE demonstrated a median overall survival of 12.7 months. Overall survival was higher in patients who had previous primary resection (P < .05), prior ablation (P < .05), or completed the scheduled TACE treatments (P < .05) but was adversely affected by the presence of extrahepatic disease (P < .05) and larger preprocedural tumor burden (P < .01). Prior systemic chemotherapy lines (P = .98) and microsphere size (P = .34) did not affect survival. Partial radiologic response to treatment using the Choi criteria (n = 28, P < .01) correlated significantly with survival, a correlation not seen with the RECIST 1.1 measurements (n = 5, P = .13). CONCLUSIONS: A partial response to treatment of unresectable colorectal liver metastases treated by TACE with IEMs measured using the Choi criteria correlated significantly with improved survival, while RECIST 1.1 measurements did not.

Transhepatic Approach for Retrograde D2 Duodenal Stent Placement: New Technique and Case Series.

Transhepatic duodenal stent placement may be a solution when endoscopy fails or when duodenal and biliary stents are needed simultaneously. This approach is usually not considered as an option when the duodenal stent must be deployed across the ampulla of Vater. The authors present a series of 10 patients who underwent a novel transhepatic technique to place a duodenal stent across the ampulla of Vater by establishing a wire scaffold from the liver toward the jejunum and then curving back on itself retrogradely through the duodenal tumor and out the mouth. Technical success was 90% with no associated mortality.

Portal Vein Embolization: Correlation of Future Liver Remnant Hypertrophy to Type of Embolic Agent Used.

PURPOSE: The purpose of this study was to compare the effectiveness of portal vein embolization (PVE) with different embolic agents used at our centre. Specifically, the effectiveness of N-butyl cyanoacrylate (NBCA) glue is compared with that of polyvinyl alcohol (PVA) particles. METHODS: We performed a retrospective chart review of all patients (N = 77) who underwent PVE at our institution over a 5-year period. Pre- and postprocedural computed tomography or magnetic resonance imaging, when available, were used to measure the volume of total liver volume and future liver remnant (FLR). The absolute values obtained were used to calculate percentage of FLR. The growth in FLR was determined 4-6 weeks after PVE. Technical details of the procedure including the type and amount of embolic agent used were obtained from the chart reviews, electronic patient records, and radiology reports. Statistical analysis was performed using Kruskal-Wallis test, Wilcoxon rank sum test, and the Spearman correlation coefficient with post hoc analysis. Results are expressed as mean ± SD (P < .05 considered statistically significant). RESULTS: NBCA (n = 29) produced a mean change in FLR of 14.8% compared with 9.3% for PVA particles (n = 24; P = .007). Mean change in FLR was 10.1% in the group where a combination of NBCA and PVA particles was used (n = 24). The effect of glue volume and glue-to-lipiodol ratio on the outcome was not found to be statistically significant (P = .5 and .7, respectively). CONCLUSIONS: We conclude that NBCA glue is a better embolic agent than PVA particles in inducing liver hypertrophy.

Consensus Recommendations for the Diagnosis and Management of Pancreatic Neuroendocrine Tumors: Guidelines from a Canadian National Expert Group.

Pancreatic neuroendocrine tumors (pNETs) are rare heterogeneous tumors that have been steadily increasing in both incidence and prevalence during the past few decades. Pancreatic NETs are categorized as functional (F) or nonfunctional (NF) based on their ability to secrete hormones that elicit clinically relevant symptoms. Specialized diagnostic tests are required for diagnosis. Treatment options are diverse and include surgical resection, intraarterial hepatic therapy, and peptide receptor radionuclide therapy (PRRT). Systemic therapy options include targeted agents as well as chemotherapy when indicated. Diagnosis and management should occur through a collaborative team of health care practitioners well-experienced in managing pNETs. Recent advances in pNET treatment options have led to the development of the Canadian consensus document described in this report. The discussion includes the epidemiology, classification, pathology, clinical presentation and prognosis, imaging and laboratory testing, medical and surgical management, and recommended treatment algorithms for pancreatic neuroendocrine cancers.

Quantitative assessment of pulmonary artery occlusion using lung dynamic perfusion CT.

Quantitative measurement of lung perfusion is a promising tool to evaluate lung pathophysiology as well as to assess disease severity and monitor treatment. However, this novel technique has not been adopted clinically due to various technical and physiological challenges; and it is still in the early developmental phase where the correlation between lung pathophysiology and perfusion maps is being explored. The purpose of this research work is to quantify the impact of pulmonary artery occlusion on lung perfusion indices using lung dynamic perfusion CT (DPCT). We performed Lung DPCT in ten anesthetized, mechanically ventilated juvenile pigs (18.6-20.2 kg) with a range of reversible pulmonary artery occlusions (0%, 40-59%, 60-79%, 80-99%, and 100%) created with a balloon catheter. For each arterial occlusion, DPCT data was analyzed using first-pass kinetics to derive blood flow (BF), blood volume (BV) and mean transit time (MTT) perfusion maps. Two radiologists qualitatively assessed perfusion maps for the presence or absence of perfusion defects. Perfusion maps were also analyzed quantitatively using a linear segmented mixed model to determine the thresholds of arterial occlusion associated with perfusion derangement. Inter-observer agreement was assessed using Kappa statistics. Correlation between arterial occlusion and perfusion indices was evaluated using the Spearman-rank correlation coefficient. Our results determined that perfusion defects were detected qualitatively in BF, BV and MTT perfusion maps for occlusions larger than 55%, 80% and 55% respectively. Inter-observer agreement was very good with Kappa scores > 0.92. Quantitative analysis of the perfusion maps determined the arterial occlusion threshold for perfusion defects was 50%, 76% and 44% for BF, BV and MTT respectively. Spearman-rank correlation coefficients between arterial occlusion and normalized perfusion values were strong (- 0.92, - 0.72, and 0.78 for BF, BV and MTT, respectively) and were statically significant (p < 0.01). These findings demonstrate that lung DPCT enables quantification and stratification of pulmonary artery occlusion into three categories: mild, moderate and severe. Severe (occlusion ≥ 80%) alters all perfusion indices; mild (occlusion < 55%) has no detectable effect. Moderate (occlusion 55-80%) impacts BF and MTT but BV is preserved.

Arterial input function placement effect on computed tomography lung perfusion maps.

BACKGROUND: A critical source of variability in dynamic perfusion computed tomography (DPCT) is the arterial input function (AIF). However, the impact of the AIF location in lung DPCT has not been investigated yet. The purpose of this study is to determine whether the location of the AIF within the central pulmonary arteries influences the accuracy of lung DPCT maps. METHODS: A total of 54 lung DPCT scans were performed in three pigs using different rates and volumes of iodinated contrast media. Pulmonary blood flow (PBF) perfusion maps were generated using first-pass kinetics in three different AIF locations: the main pulmonary trunk (PT), the right main (RM) and the left main (LM) pulmonary arteries. A total of 162 time density curves (TDCs) and corresponding PBF perfusion maps were generated. Linear regression and Spearman's rank correlation coefficient were used to compare the TDCs. PBF perfusion maps were compared quantitatively by taking twenty six regions of interest throughout the lung parenchyma. Analysis of variance (ANOVA) was used to compare the mean PBF values among the three AIF locations. Two chest radiologists performed qualitative assessment of the perfusion maps using a 3-point scale to determine regions of perfusion mismatch. RESULTS: The linear regression of the TDCs from the RM and LM compared to the PT had a median (range) of 1.01 (0.98-1.03). The Spearman rank correlation between the TDCs was 0.88 (P<0.05). ANOVA analysis of the perfusion maps demonstrated no statistical difference (P>0.05). Qualitative comparison of the perfusion maps resulted in scores of 1 and 2, demonstrating either identical or comparable maps with no significant difference in perfusion defects between the different AIF locations. CONCLUSIONS: Accurate PBF perfusion maps can be generated with the AIF located either at the PT, RM or LM pulmonary arteries.

Diagnosis and management of gastrointestinal neuroendocrine tumors: An evidence-based Canadian consensus.

The majority of neuroendocrine tumors originate in the digestive system and incidence is increasing within Canada and globally. Due to rapidly evolving evidence related to diagnosis and clinical management, updated guidance on the diagnosis and treatment of gastrointestinal neuroendocrine tumors (GI-NETs) are of clinical importance. Well-differentiated GI-NETs may exhibit indolent clinical behavior and are often metastatic at diagnosis. Some NET patients will develop secretory disease requiring symptom control to optimize quality of life and clinical outcomes. Optimal management of GI-NETs is in a multidisciplinary environment and is multimodal, requiring collaboration between medical, surgical, imaging and pathology specialties. Clinical application of advances in pathological classification and diagnostic technologies, along with evolving surgical, radiotherapeutic and medical therapies are critical to the advancement of patient care. We performed a systematic literature search to update our last set of published guidelines (2010) and identified new level 1 evidence for novel therapies, including telotristat etiprate (TELESTAR), lanreotide (CLARINET), everolimus (RADIANT-2; RADIANT-4) and peptide receptor radionuclide therapy (PRRT; NETTER-1). Integrating these data with the clinical knowledge of 16 multi-disciplinary experts, we devised consensus recommendations to guide state of the art clinical management of GI-NETs.