Reproducibility and efficiency of liver volumetry using manual method and liver analysis software.

BACKGROUND: For liver volumetry, manual tracing on computed tomography (CT) images is time-consuming and operator dependent. To overcome these disadvantages, several three-dimensional simulation software programs have been developed; however, their efficacy has not fully been evaluated. METHODS: Three physicians performed liver volumetry on preoperative CT images on 30 patients who underwent formal right hepatectomy, using manual tracing volumetry and two simulation software programs, SYNAPSE and syngo.via. The future liver remnant (FLR) was calculated using each method of volumetry. The primary endpoint was reproducibility and secondary outcomes were calculation time and learning curve. RESULTS: The mean FLR was significantly lower for manual volumetry than for SYNAPSE or syngo.via; there was no significant difference in mean FLR between the two software-based methods. Reproducibility was lower for the manual method than for the software-based methods. Mean calculation time was shortest for SYNAPSE. For the two physicians unfamiliar with the software, no obvious learning curve was observed for using SYNAPSE, whereas learning curves were observed for using syngo.via. CONCLUSIONS: Liver volumetry was more reproducible and faster with three-dimensional simulation software, especially SYNAPSE software, than with the conventional manual tracing method. Software can help even inexperienced physicians learn quickly how to perform liver volumetry.

Evaluating the benefit of surgical resection for hepatocellular carcinoma with multifocality or intrahepatic vascular invasion.

BACKGROUND: The role of hepatectomy for hepatocellular carcinoma (HCC) with multifocality or intrahepatic vascular involvement remains ill-defined. Our objective was to evaluate benefits of surgical resection for patients with these high-risk features. METHODS: The National Cancer Database was used to identify HCC patients with vascular involvement and/or multifocality (T2/T3, N-/M-) from 2011 to 2015. Propensity score matching (k-nearest neighbors, no replacement, 1:1) grouped patients by treatment: surgical resection versus non-surgical modalities. Groups were matched using patient, clinical, and liver-specific characteristics. Median overall survival (OS) was calculated using Kaplan-Meier, and adjusted analyses were performed using shared frailty models. RESULTS: 14,557 patients met inclusion criteria, including 1892 (9.4%) treated with surgical resection. Median cohort OS was 20.5 months. After adjustment, surgical resection was associated with survival advantage compared to non-surgical treatment (37.8 versus 15.7 months, log-rank P < .001; adjusted hazard ratio 0.49, 95% confidence interval, 0.45-0.54). Patients with minimal comorbidity, unifocal disease, and age <54 had highest probability of survival one year post-surgery. CONCLUSIONS: Surgical resection is associated with a survival advantage in HCC with multifocality and/or intrahepatic vascular involvement. The presence of these features should not contraindicate consideration of hepatectomy in suitable surgical candidates.

Impact of cumulative operative time on postoperative complication risk in simultaneous resections of colorectal liver metastases and primary tumors.

BACKGROUND: Simultaneous resection of colorectal liver metastases (CLM) and primary colorectal cancers (CRC) is nuanced without firm rules for selection. This study aimed to identify factors associated with morbidity after simultaneous resection. METHODS: Using a prospective database, patients undergoing simultaneous CLM-CRC resection from 1/1/2017-7/1/2020 were analyzed. Regression modeling estimated impact of colorectal resection type, Kawaguchi-Gayet (KG) hepatectomy complexity, and perioperative factors on 90-day complications. RESULTS: Overall, 120 patients underwent simultaneous CLM-CRC resection. Grade≥2 complications occurred in 38.3% (n = 46); these patients experienced longer length of stay (median LOS 7.5 vs. 4, p < 0.001) and increased readmission (39% vs. 1.4%, p < 0.001) compared to patients with zero or Grade 1 complications. Median OR time was 298 min. Patients within highest operative time quartile (>506 min) had higher grade≥2 complications (57%vs. 23%, p = 0.04) and greater than 4-fold increased odds of grade≥2 morbidity (OR 4.3, 95% CI (Confidence Interval) 1.41-13.1, p = 0.01). After adjusting for Pringle time, KG complexity and colorectal resection type, increasing operative time was associated with grade≥2 complications, especially for resections in highest quartile of operative time (OR 7.28, 95% CI 1.73-30.6, p = 0.007). CONCLUSION: In patients undergoing simultaneous CLM-CRC resection, prolonged operative time is independently associated with grade≥2 complications. Awareness of cumulative operative time may inform intraoperative decision-making by surgical teams.

Overall Body Composition and Sarcopenia Are Associated with Poor Liver Hypertrophy Following Portal Vein Embolization.

PURPOSE: To explore whether body composition and/or sarcopenia are associated with liver hypertrophy following portal vein embolization (PVE) in patients with colorectal liver metastases (CLM). METHODS: Patients with CLM who underwent right PVE prior to a planned right hepatectomy were identified from the institutional liver database from 2004 to 2014. Patients were excluded due to previous liver-directed therapy/hepatectomy, right PVE + segment IV embolization, or planned 2-stage hepatectomy. Advanced imaging software was used to measure body compartment volumes (cm2), which were standardized to height (m2) to create an index: skeletal muscle index (SMI), subcutaneous adipose index (SAI), and visceral adipose index (VAI). SMI, gender, and body mass index (BMI) were used to define sarcopenia. The main outcome of interest was hypertrophy of the future liver remnant (FLR) following PVE, which was reported as degree of hypertrophy (DH) and kinetic growth rate (KGR). RESULTS: Patients were evenly divided into three KGR groups: lower third (KGR:0.7-2.0%), middle third (KGR:2.0-4.1%), and upper third (KGR:4.2-12.3%). Patients in the lower third KGR group had a lower VAI (31.0 vs 53.0 vs 54.5 cm2/m2, p = 0.042) and were more commonly sarcopenic (60%) compared to the upper third (20%, p = 0.025). Eighteen patients (40%) met criteria for sarcopenia. Sarcopenic patients had a lower VAI (29.1 vs 57.4 cm2/m2, p = 0.004), lesser degree of hypertrophy (8.3% vs 15.2%, p = 0.009), and lower KGR (2.0% vs 4.0%, p = 0.012). CONCLUSION: Sarcopenia and associated body composition indices are strongly associated with clinically relevant impaired liver regeneration, which may result in increased liver-specific complications following hepatectomy for CLM.

Characteristics of atypical large well-differentiated hepatocellular carcinoma: a specific subtype of hepatocellular carcinoma?

BACKGROUND: Hepatocellular carcinoma (HCC) de-differentiation is thought to correlate with size, therefore well-differentiated HCC ≥3 cm are considered rare and not fully understood. METHODS: Patients who underwent hepatectomy for HCC between 1998-2016 were retrospectively analyzed. Patient's characteristics and recurrence-free (RFS) and overall (OS) survival were compared between those with atypical- (well-differentiated-HCC ≥3 cm) and typical-HCC (moderate-to-poorly-differentiated HCC ≥3 cm). RESULTS: Of 176 patients included in this study, 37 (21%) had atypical-HCC. Patients with atypical-HCC were less likely to be Asian ethnicity (3% vs. 17%, p = 0.062), have lower rate of viral infection (14% vs. 43%, p = 0.003), cirrhosis (8% vs. 27%, p = 0.015). The tumors were less likely to demonstrate vascular invasion (30% vs. 59%, p = 0.002), and were associated with a lower alpha-fetoprotein level (3.5 ng/ml vs. 33.2 ng/ml, p < 0.001). Patients with atypical-HCC had a longer RFS (5-y RFS: 58.3% vs. 35.7%, p = 0.016) and OS (5-y OS: 79.1% vs 53.3%, p = 0.029) as compared to those with typical-HCC following univariate analysis, however this did not appear following multivariate analysis. CONCLUSION: Patients with atypical-HCC have different characteristic in terms of epidemiology, etiology, cirrhosis and vascular invasion as compared to typical-HCC. The etiology of atypical-HCC may be non-alcoholic fatty liver disease-related and/or malignant transformation of hepatocellular adenoma.

Incidental versus non-incidental gallbladder cancer: index cholecystectomy before oncologic re-resection negatively impacts survival in T2b tumors.

BACKGROUND: Conflicting data exists whether non-oncologic index cholecystectomy (IC) leading to discovery of incidental gallbladder cancer (IGBC) negatively impacts survival. This study aimed to determine whether a subgroup of patients derives a disadvantage from IC. METHODS: Patients with IGBC and non-IGBC treated at an academic USA and Chilean center during 1999-2016 were compared. Patients with T1, T4 tumor or preoperative jaundice were excluded. T2 disease was classified into T2a (peritoneal-side tumor) and T2b (hepatic-side tumor). Disease-specific survival (DSS) and its predictors were analyzed. RESULTS: Of the 196 patients included, 151 (77%) had IGBC. One hundred thirty-six (90%) patients of whom 118 (87%) had IGBC had T2 disease. Three-year DSS rates were similar between IGBC and non-IGBC for all patients. However, for T2b patients, 3-year survival rate was worse for IGBC (31% vs 85%; p = 0.019). In multivariate analysis of T2 patients, predictors of poor DSS were hepatic-side tumor hazard ratio [HR], 2.9; 95% CI, 1.6-5.4; p = 0.001) and N1 status (HR, 2.4; 95% CI, 1.6-3.6; p < 0.001). CONCLUSIONS: Patients with T2b gallbladder cancer specifically benefit from a single operation. These patients should be identified preoperatively and referred to hepatobiliary center.

Remnant Liver Ischemia as a Prognostic Factor for Cancer-Specific Survival After Resection of Colorectal Liver Metastases.

IMPORTANCE: Ischemia-reperfusion injury during hepatic resection has been shown to accelerate progression of liver cancer. However, the prognostic relevance of remnant liver ischemia (RLI) after resection of colorectal liver metastases (CLMs) is unknown to date. OBJECTIVES: To assess the prognostic influence of RLI after resection of CLMs and to identify correlates of greater extent of RLI. DESIGN, SETTING, AND PARTICIPANTS: This study was a retrospective analysis at The University of Texas MD Anderson Cancer Center based on prospectively collected data. The study identified 202 patients who underwent curative resection of CLMs between January 1, 2008, and December 31, 2014, and had enhanced computed tomographic images obtained within 30 days after surgery. MAIN OUTCOMES AND MEASURES: Remnant liver ischemia was defined as reduced or absent contrast enhancement during the portal phase. Postoperative RLI was classified as grade 0 (none), 1 (marginal), 2 (partial), 3 (segmental), or 4 (necrotic) as previously defined. Experienced members of the surgical team retrospectively performed imaging assessments. Team members were masked to the postoperative outcomes. Survival after resection was stratified by RLI grade. Predictors of RLI grade 2 or higher and survival were identified. RESULTS: Among 202 patients (median [range] age, 56 [27-87] years; 84 female), the RLI grades were as follows: grade 0 (105 patients), grade 1 (47 patients), grade 2 (45 patients), grade 3 (5 patients), and grade 4 (0 patients). Recurrence-free survival (RFS) and cancer-specific survival (CSS) rates after hepatic resection were worse in patients with RLI grade 2 or higher vs grade 1 or lower (RFS at 3 years, 6.4% [3 of 50] vs 39.2% [60 of 152]; P < .001 and CSS at 5 years, 20.7% [10 of 50] vs 63.7% [97 of 152]; P < .001). A largest metastasis at least 3 cm (OR, 2.74; 95% CI, 1.35-5.70; P = .005), multiple CLMs (OR, 2.51; 95% CI, 1.25-5.24; P = .009), and nonanatomic resection (odds ratio [OR], 3.29; 95% CI, 1.52-7.63; P = .002) were associated with RLI grade 2 or higher. A largest metastasis at least 3 cm (hazard ratio [HR], 1.70; 95% CI, 1.01-2.88; P = .045), mutant RAS (HR, 2.15; 95% CI, 1.27-3.64; P = .005), and RLI grade 2 or higher (HR, 2.90; 95% CI, 1.69-4.84; P < .001) were associated with worse CSS. CONCLUSIONS AND RELEVANCE: In this study, remnant liver ischemia grade 2 or higher was associated with worse CSS after resection of CLMs. High-quality anatomic surgery to minimize RLI after resection is essential.

Comparative effectiveness of first-line radiofrequency ablation versus surgical resection and transplantation for patients with early hepatocellular carcinoma.

BACKGROUND: Significant controversy exists as to which treatment modality is most effective for small, solitary hepatocellular carcinomas (HCCs): radiofrequency ablation (RFA), surgical resection (RXN), or transplantation (TXP). Size cutoff values ranging from 20 to 50 mm have been proposed to achieve complete ablation. The current study compares outcomes between RFA, RXN, and TXP as first-line therapy for patients with HCC tumors measuring as large as 50 mm. METHODS: The Surveillance, Epidemiology, and End Results database was queried for patients with HCC tumors measuring up to 50 mm who were treated with RFA, RXN, or TXP between 2004 and 2013. Overall survival (OS) and disease-specific survival (DSS) were examined in patients with tumors measuring ≤20 mm, 21 to 30 mm, or 31 to 50 mm. The impact of an increase in tumor size of only 5 mm beyond 30 mm was evaluated by also examining outcomes in patients with tumors measuring 31 to 35 mm. RESULTS: Of 1894 cases, patients with HCC tumors measuring ≤20 mm and 21 to 30 mm demonstrated no difference in OS or DSS regardless of whether RFA and RXN was used. RFA was associated with a worse OS and DSS than TXP, whereas there was no difference in OS observed between RXN and TXP. In patients with tumors measuring 31 to 50 mm, OS and DSS were worse with RFA compared with RXN or TXP. Most important, the inferior DSS and OS noted with RFA were observed with only a 5-mm increase in tumors measuring >30 mm. CONCLUSIONS: Although RFA frequently is used as first-line treatment of HCC tumors measuring as large as 50 mm, it is associated with worse results than RXN or TXP for tumors measuring >30 mm. To the best of the authors' knowledge, the results of the current study are the first to demonstrate that although RFA is an appropriate option for patients with HCC tumors measuring ≤30 mm, its use for tumors even slightly larger than 30 mm is associated with inferior outcomes. Cancer 2017;123:1817-1827. © 2017 American Cancer Society.

RAS Mutation Is Associated with Decreased Survival in Patients Undergoing Repeat Hepatectomy for Colorectal Liver Metastases.

BACKGROUND: The relationship between RAS mutation status and outcome for patients undergoing repeat hepatectomy (RH) for recurrent colorectal liver metastases (CLM) has not been defined. OBJECTIVE: The objective of this study was to evaluate the relationship between RAS mutation status and outcome in patients undergoing RH for CLM. METHODS: All patients who underwent RH for CLM with known RAS mutation status between January 2005 and November 2014 were identified, and the outcomes of patients with and without RAS mutations were compared. RESULTS: Ninety-eight patients underwent RH, of whom 34 (35 %) harbored a RAS mutation. Wild-type (WT) and mutant RAS groups had similar clinicopathologic characteristics. Median recurrence-free survival (RFS) for patients with WT and mutant RAS was 12.2 and 6.1 months, respectively (p = 0.03). Median overall survival (OS) for the WT and mutant RAS patients were 42.5 and 26.6 months, respectively (p < 0.01). On multivariate analysis, RAS mutations [hazard ratio (HR) = 1.69, p = 0.04] were associated with worse RFS, while multiple tumors (HR = 1.92, p = 0.045) and RAS mutations (HR = 2.11, p = 0.02) predicted worse OS. CONCLUSION: Patients with recurrent CLM that harbor RAS mutations have worse RFS and OS than patients with WT RAS, and RAS mutations are independently associated with worse RFS and OS. RAS mutation status should be determined prior to RH, as it may impact treatment decisions.

Is hepatectomy justified for patients with RAS mutant colorectal liver metastases? An analysis of 524 patients undergoing curative liver resection.

BACKGROUND: RAS mutations are associated with limited overall survival after resection of colorectal liver metastases. Our aim was to determine criteria for considering hepatectomy for patients with RAS mutant colorectal liver metastases. METHODS: Of 1,163 patients who underwent liver resection for colorectal liver metastases during 2005-2014, all patients operated on with curative intent who had known RAS mutation status were included. Factors associated with overall survival were determined using multivariate analysis. RESULTS: A total of 524 patients met the inclusion criteria; 212 (40%) had mutated RAS. Mutations were located on codon 12 in 128 patients (60%) and codon 13 in 29 (14%). At median follow-up of 38 months, median overall survival was 72.6 months for wild-type RAS and 50.9 months for mutated RAS (P < .001). Median overall survival for patients with codon 12 and 13 mutations was 51.9 and 50.9 months, respectively (P = .839), significantly worse than for patients with wild-type RAS (P = .005, and P = .038 for codon 12 and 13, respectively). For patients with RAS mutation, factors associated independently with worse overall survival were node-positive primary tumor, tumor >3 cm, and >7 cycles of preoperative chemotherapy. Major and 2-stage hepatectomy were not associated independently with overall survival. Median overall survival was 57, 41, and 21.5 months for patients with 1, 2, and 3 risk factors, respectively. There were no 4-year survivors in the highest-risk group. CONCLUSION: Patients with multiple risk factors had poor overall survival after curative resection of RAS mutant colorectal liver metastases. For such patients, hepatectomy may be ill advised, and alternative therapies or further systemic therapy should be considered.

Association of Common Genetic Polymorphisms with Melanoma Patient IL-12p40 Blood Levels, Risk, and Outcomes.

Recent investigation has identified association of IL-12p40 blood levels with melanoma recurrence and patient survival. No studies have investigated associations of single-nucleotide polymorphisms (SNPs) with melanoma patient IL-12p40 blood levels or their potential contributions to melanoma susceptibility or patient outcome. In the current study, 818,237 SNPs were available for 1,804 melanoma cases and 1,026 controls. IL-12p40 blood levels were assessed among 573 cases (discovery), 249 cases (case validation), and 299 controls (control validation). SNPs were evaluated for association with log[IL-12p40] levels in the discovery data set and replicated in two validation data sets, and significant SNPs were assessed for association with melanoma susceptibility and patient outcomes. The most significant SNP associated with log[IL-12p40] was in the IL-12B gene region (rs6897260, combined P=9.26 × 10(-38)); this single variant explained 13.1% of variability in log[IL-12p40]. The most significant SNP in EBF1 was rs6895454 (combined P=2.24 × 10(-9)). A marker in IL12B was associated with melanoma susceptibility (rs3213119, multivariate P=0.0499; OR=1.50, 95% CI 1.00-2.24), whereas a marker in EBF1 was associated with melanoma-specific survival in advanced-stage patients (rs10515789, multivariate P=0.02; HR=1.93, 95% CI 1.11-3.35). Both EBF1 and IL12B strongly regulate IL-12p40 blood levels, and IL-12p40 polymorphisms may contribute to melanoma susceptibility and influence patient outcome.

Locoregional surgical and interventional therapies for advanced colorectal cancer liver metastases: expert consensus statements.

Selection of the optimal surgical and interventional therapies for advanced colorectal cancer liver metastases (CRLM) requires multidisciplinary discussion of treatment strategies early in the trajectory of the individual patient's care. This paper reports on expert consensus on locoregional and interventional therapies for the treatment of advanced CRLM. Resection remains the reference treatment for patients with bilateral CRLM and synchronous presentation of primary and metastatic cancer. Patients with oligonodular bilateral CRLM may be candidates for one-stage multiple segmentectomies; two-stage resection with or without portal vein embolization may allow complete resection in patients with more advanced disease. After downsizing with preoperative systemic and/or regional therapy, curative-intent hepatectomy requires resection of all initial and currently known sites of disease; debulking procedures are not recommended. Many patients with synchronous primary disease and CRLM can safely undergo simultaneous resection of all disease. Staged resections should be considered for patients in whom the volume of the future liver remnant is anticipated to be marginal or inadequate, who have significant medical comorbid condition(s), or in whom extensive resections are required for the primary cancer and/or CRLM. Priority for liver-first or primary-first resection should depend on primary tumour-related symptoms or concern for the progression of marginally resectable CRLM during treatment of the primary disease. Chemotherapy delivered by hepatic arterial infusion represents a valid option in patients with liver-only disease, although it is best delivered in experienced centres. Ablation strategies are not recommended as first-line treatments for resectable CRLM alone or in combination with resection because of high local failure rates and limitations related to tumour size, multiplicity and intrahepatic location.

Two-surgeon technique of parenchymal transection contributes to reduced transfusion rate in patients undergoing major hepatectomy: analysis of 1,557 consecutive liver resections.

BACKGROUND: Blood transfusions are an independent risk factor for adverse outcomes after hepatectomy. In-hospital transfusions are still reported in one third of patients in major series. Data on factors affecting blood transfusions in large series of liver resection are limited. The aim of this study was to evaluate factors predictive of blood transfusion in hepatectomies performed at a tertiary referral center. METHODS: Records of 1,477 patients who underwent 1,557 liver resections between 1998 and 2007 were reviewed. Multivariate analysis of risk factors for red cell transfusion was performed. RESULTS: Median intra-operative blood loss was 250 cc, and 30-day peri-operative red cell transfusion rate was 27%. On multivariate analysis, factors that significantly predicted increased red cell transfusion rates were female sex, pre-operative hematocrit<30%, platelet count<100,000/mm3, simultaneous resection of other organs, major hepatic resection, use of the Pringle maneuver, and tumors>10 cm. Parenchymal transection technique was an independent risk factor for perioperative red cell transfusion; the usage of the 2-surgeon technique (combined saline-linked cautery and ultrasonic dissection) was associated with a lower transfusion rate than other techniques, including ultrasonic dissection alone, finger fracture, and stapling (P<.001). CONCLUSION: Although most factors that affect the red cell transfusion rate for liver resection are patient- or tumor-related, the parenchymal transection technique is under the surgeon's control. The decrease in transfusion rate associated with the use of the 2-surgeon technique emphasizes the important role of the hepatobiliary surgeon in determining outcomes after liver resection.

Major hepatic resection for hepatocellular carcinoma with or without portal vein embolization: Perioperative outcome and survival.

BACKGROUND: Preoperative portal vein embolization (PVE) is performed to minimize perioperative risks of major hepatic resection for hepatocellular carcinoma (HCC), but its effects on tumor growth are ill defined. Perioperative outcome and survival after major hepatic resection for HCC, with and without PVE, were investigated. METHODS: Patients that underwent major hepatic resection (> or =3 segments) for HCC between January 1998 and May 2007 were analyzed retrospectively. Preoperative PVE was performed when the remnant liver volume was predicted to be insufficient. RESULTS: A total of 54 patients underwent major hepatic resection for HCC: 21 patients with PVE before resection (PVE group) and 33 patients without PVE (non-PVE group). PVE and non-PVE groups had similar rates of fibrosis or cirrhosis, hepatitis C virus, hepatitis B virus, American Joint Committee on Cancer stage, preoperative transarterial chemoembolization, overall postoperative complications, and positive margin (P = nonsignificant for all rates). There were no perioperative deaths in the PVE group and 6 (18%) deaths in the non-PVE group (P = .038). Median follow-up was 21 months. Excluding perioperative deaths, overall survival rates at 1, 3, and 5 years were 94%, 82%, and 72%, respectively, in the PVE group and 93%, 63%, and 54%, respectively, in the non-PVE group (P = .35). Similarly, disease-free survival (DFS) rates were not significantly different between the groups, with 1-, 3-, and 5-year DFS rates of 84%, 56%, and 56%, respectively, in the PVE group and 66%, 49%, and 49%, respectively, in the non-PVE group (P = .38). CONCLUSION: PVE before major hepatic resection for HCC is associated with improved perioperative outcome. Excluding perioperative mortality, overall survival and DFS rates were similar between patients with and without preoperative PVE.

Pediatric inflammatory myofibroblastic tumor: anaplastic lymphoma kinase (ALK) expression and prognosis.

BACKGROUND: Pediatric inflammatory myofibroblastic tumor (IMT) is rare, with unpredictable clinical behavior. Recently, it has been associated with anaplastic lymphoma kinase (ALK) expression. METHODS: Patients under age 16, treated for IMT between 1976 and 2000 were reviewed. Mean follow-up was 8 years (range 1 month-22 years). RESULTS: Eight children had IMT, with a mean age of 6 years (range, 11 months-14 years) and female to male ratio of 3:1. Tumor location was lung (four patients), abdomen (two patients), lung and abdomen (one patient), and abdomen, head, and neck (one patient). Presenting symptoms included anemia (seven patients), fever (six patients), and dyspnea (four patients). Laboratory results included thrombocytosis (six patients), hypergammaglobulinemia (four patients), elevated sedimentation rate (four patients), and leukocytosis (three patients). Immunohistochemistry revealed ALK expression in four of eight tumors. Four children had complete resection and are alive. Two of these children had ALK-positive tumors. Four patients had incomplete resection, and two had recurrences treated successfully with resection and radiotherapy; the other two died of disease. For the incomplete resection patients, those that were ALK-positive lived, and those that were ALK-negative did not. CONCLUSIONS: Eight children were treated for IMT over a 15-year period. ALK expression was found in half the tumors. Prognosis was improved with ALK expression and complete surgical resection.