Population dynamics of mites in slow-release sachets used in biological control: a new study methodology.

Predatory mite species (Acari: Phytoseiidae) are essential tools in the biological control of greenhouses pests. The natural enemies can be released directly into a crop. A better, partly preventive system is to place slow-release sachets on the plants. Inside such sachets is a factitious prey's food substrate-which also acts as refuge-and the predator. The objective of this study was to develop a new methodology to evaluate the population dynamics of this sachet system, based on the factitious prey Carpoglyphus lactis and the predatory mite Amblyseius swirskii. Through two tests carried out under laboratory conditions, the sachets were first compared to the traditional extraction method that uses Berlese-Tullgren funnels and an extraction method using flotation in hexane. The latter method proved more effective at sampling the motile states (larvae, nymphs, and adults), both for the predatory species and for the factitious prey, extracting up to 3.7 × more mites than the Berlese-Tullgren funnel. Second, the population dynamics of both mite species was studied in a laboratory test, both inside and outside the sachets. In this way, a positive correlation was demonstrated between the number of predatory mites and the number of prey mites inside the sachets. Conversely, no correlation was found between the interior population of predatory mites and the number that venture outside. We can conclude that hexane extraction is very useful both in quality control of predatory mites and in studying how the sachets behave when faced with various factors.

Radiation therapy strategies for skull-base malignancies.

INTRODUCTION: The management of skull base malignancies continues to evolve with improvements in surgical technique, advances in radiation delivery and novel systemic agents. METHODS: In this review, we aim to discuss in detail the management of common skull base pathologies which typically require multimodality therapy, focusing on the radiotherapeutic aspects of care. RESULTS: Technological advances in the administration of radiation therapy have led to a wide variety of different treatment strategies for the treatment of skull base malignances, with outcomes summarized herein. CONCLUSION: Radiation treatment plays a key and critical role in the management of patients with skull base tumors. Recent advancements continue to improve the risk/benefit ratio for radiotherapy in this setting.

Does the Antitumor Necrosis Factor-α Therapy Decrease the Vertebral Fractures Occurrence in Inflammatory Bowel Disease?

BACKGROUND/OBJECTIVE: Osteoporosis and osteoporotic fracture risk are extraintestinal manifestations of the inflammatory bowel disease, whose etiopathogenic mechanisms have not been determined yet. Anti-tumor necrosis factor (TNF)-α are used in treatment of inflammatory bowel disease (IBD), but it is unknown if they play a role in osteoporotic fracture prevention. The objective of this study was to know if anti-TNF decreases fracture risk or modifies bone mineral density. To determine the possible risk factors associated with fractures, and assess the incidence of vertebral fractures in IBD patients. METHODS: Longitudinal prospective cohort study (7 yr of follow-up); which included 71 IBD patients, 23 received anti-TNF-α; the remaining 48 received conventional treatment, constituted the control group. Patients participated in a questionnaire which gathered risk factors associated with the development of osteoporosis and fractures. Radiographs of the dorsolumbar-spine were performed and also a bone density measurement. Their biochemical and bone remodeling parameters were determined. RESULTS: Although patients who did not receive anti-TNF-α, suffered more fractures but biologic therapy did not reduce the risk of new vertebral fractures. The increase of bone mass was significantly higher the group treated with anti-TNF-α. The increase in the lumbar spine was of 8% and in the femoral neck was of 6.7%. The only determinant factor for the incidence of vertebral fractures was a history of previous fractures (odds ratio of 12.8; confidence interval 95% 2.37-69.9; p = 0.003). The incidence of vertebral fractures in IBD patients was considerably high: 26.7/700 patient-yr. CONCLUSIONS: Anti-TNF-α, although increased bone mass in these patients, did not reduce the risk of new vertebral fractures. In this study, patients with IBD have a considerably high incidence of fractures. Only the existence of previous vertebral fractures was a predictive factor for consistent fractures.

Randomized control trial to assess the efficacy of metacognitive training compared with a psycho-educational group in people with a recent-onset psychosis.

BACKGROUND: Aims were to assess the efficacy of metacognitive training (MCT) in people with a recent onset of psychosis in terms of symptoms as a primary outcome and metacognitive variables as a secondary outcome. METHOD: A multicenter, randomized, controlled clinical trial was performed. A total of 126 patients were randomized to an MCT or a psycho-educational intervention with cognitive-behavioral elements. The sample was composed of people with a recent onset of psychosis, recruited from nine public centers in Spain. The treatment consisted of eight weekly sessions for both groups. Patients were assessed at three time-points: baseline, post-treatment, and at 6 months follow-up. The evaluator was blinded to the condition of the patient. Symptoms were assessed with the PANSS and metacognition was assessed with a battery of questionnaires of cognitive biases and social cognition. RESULTS: Both MCT and psycho-educational groups had improved symptoms post-treatment and at follow-up, with greater improvements in the MCT group. The MCT group was superior to the psycho-educational group on the Beck Cognitive Insight Scale (BCIS) total (p = 0.026) and self-certainty (p = 0.035) and dependence self-subscale of irrational beliefs, comparing baseline and post-treatment. Moreover, comparing baseline and follow-up, the MCT group was better than the psycho-educational group in self-reflectiveness on the BCIS (p = 0.047), total BCIS (p = 0.045), and intolerance to frustration (p = 0.014). Jumping to Conclusions (JTC) improved more in the MCT group than the psycho-educational group (p = 0.021). Regarding the comparison within each group, Theory of Mind (ToM), Personalizing Bias, and other subscales of irrational beliefs improved in the MCT group but not the psycho-educational group (p < 0.001-0.032). CONCLUSIONS: MCT could be an effective psychological intervention for people with recent onset of psychosis in order to improve cognitive insight, JTC, and tolerance to frustration. It seems that MCT could be useful to improve symptoms, ToM, and personalizing bias.

Ecological monitoring in a discrete-time prey-predator model.

The paper is aimed at the methodological development of ecological monitoring in discrete-time dynamic models. In earlier papers, in the framework of continuous-time models, we have shown how a systems-theoretical methodology can be applied to the monitoring of the state process of a system of interacting populations, also estimating certain abiotic environmental changes such as pollution, climatic or seasonal changes. In practice, however, there may be good reasons to use discrete-time models. (For instance, there may be discrete cycles in the development of the populations, or observations can be made only at discrete time steps.) Therefore the present paper is devoted to the development of the monitoring methodology in the framework of discrete-time models of population ecology. By monitoring we mean that, observing only certain component(s) of the system, we reconstruct the whole state process. This may be necessary, e.g., when in a complex ecosystem the observation of the densities of certain species is impossible, or too expensive. For the first presentation of the offered methodology, we have chosen a discrete-time version of the classical Lotka-Volterra prey-predator model. This is a minimal but not trivial system where the methodology can still be presented. We also show how this methodology can be applied to estimate the effect of an abiotic environmental change, using a component of the population system as an environmental indicator. Although this approach is illustrated in a simplest possible case, it can be easily extended to larger ecosystems with several interacting populations and different types of abiotic environmental effects.

Systematic Implementation of Effective Quality Assurance Processes for the Assessment of Radiation Target Volumes in Head and Neck Cancer.

PURPOSE: Significant heterogeneity exists in clinical quality assurance (QA) practices within radiation oncology departments, with most chart rounds lacking prospective peer-reviewed contour evaluation. This has the potential to significantly affect patient outcomes, particularly for head and neck cancers (HNC) given the large variance in target volume delineation. With this understanding, we incorporated a prospective systematic peer contour-review process into our workflow for all patients with HNC. This study aims to assess the effectiveness of implementing prospective peer review into practice for our National Cancer Institute Designated Cancer Center and to report factors associated with contour modifications. METHODS AND MATERIALS: Starting in November 2020, our department adopted a systematic QA process with real-time metrics, in which contours for all patients with HNC treated with radiation therapy were prospectively peer reviewed and graded. Contours were graded with green (unnecessary), yellow (minor), or red (major) colors based on the degree of peer-recommended modifications. Contours from November 2020 through September 2021 were included for analysis. RESULTS: Three hundred sixty contours were included. Contour grades were made up of 89.7% green, 8.9% yellow, and 1.4% red grades. Physicians with >12 months of clinical experience were less likely to have contour changes requested than those with <12 months (8.3% vs 40.9%; P < .001). Contour grades were significantly associated with physician case load, with physicians presenting more than the median number of 50 cases having significantly less modifications requested than those presenting <50 (6.7% vs 13.3%; P = .013). Physicians working with a resident or fellow were less likely to have contour changes requested than those without a trainee (5.2% vs 12.6%; P = .039). Frequency of major modification requests significantly decreased over time after adoption of prospective peer contour review, with no red grades occurring >6 months after adoption. CONCLUSIONS: This study highlights the importance of prospective peer contour-review implementation into systematic clinical QA processes for HNC. Physician experience proved to be the highest predictor of approved contours. A growth curve was demonstrated, with major modifications declining after prospective contour review implementation. Even within a high-volume academic practice with subspecialist attendings, >10% of patients had contour changes made as a direct result of prospective peer review.

Preservation of the native spleen in multivisceral transplantation.

The native spleen is usually removed in patients undergoing MTV. The consequential asplenic state is associated with a high risk of sepsis, especially in immunosuppressed children. In contrast, the inclusion of an allogeneic spleen in multivisceral grafts has been associated with a high incidence of GVHD. We propose an alternative technique for patients undergoing MTV, consisting of the preservation of the native spleen. This approach avoids the additional risk of infection that characterizes the asplenic state without the detrimental side effects of the allogeneic spleen.

Embryonal sarcoma of the liver.

PURPOSE: Embryonal sarcoma accounts for 6 % of liver tumors. This study reviews its features and the results of treatment in a referral center. METHODS: We retrospectively reviewed liver tumors treated between 1995 and 2011. PRETEXT staging and biopsy were used to tailor chemotherapy according to SIOP protocols. Radical surgery was performed when possible. Complications and cumulative survival were the outcome endpoints. RESULTS: Six out of 156 primary liver tumors (four males and two females) were sarcomas. The mean age at diagnosis was 81 ± 8.5 months. The most frequent finding was abdominal mass. Alfa-fetoprotein was normal. Imaging depicted heterogeneous tumors with septa, necrosis, and hemorrhagic areas. The diagnosis was ascertained by biopsy. Three tumors were located in the right lobe (PRETEXT II): two were bilobar (PRETEXT III) and one was in the left lobe (PRETEXT I). Two children had metastases at diagnosis and high-risk chemotherapy (vincristine, carboplatin, epirubicin) was administered with poor response. They died without operation 4 and 10 months later. Four patients with local disease underwent typical liver resections after chemotherapy (iphosphamide, vincristine, actinomycin D, and doxorrubicin). Overall actuarial survival at 70 months was 66.6 %. CONCLUSIONS: Extended and metastatic embryonal sarcoma do poorly whereas localized tumors amenable to complete surgical removal after chemotherapy can cure.

[Do men and women have the same risk factors for hip fractures?]. / ¿Se fracturan la cadera los hombres y las mujeres ante los mismos factores de riesgo?

BACKGROUND AND AIMS: Osteoporosis has been traditionally considered as a disease in women. However, it is now known that this condition is also important in men. It is a multifactor condition whose main independent risk factor to suffer fractures, in general, and those of the hip, specifically, is bone mass. Nonetheless, there are other independent risk factors of importance. This study has aimed to study if men and women suffer hip fractures with the same bone mass and if they have the same risk factors associated to this condition. PATIENTS AND METHODS: We studied 105 patients with non-traumatic hip fracture and 68 healthy controls. The different risk factors were analyzed, including clinical data, lifestyle, analytic data, data related to bone metabolism and sex hormones as well as a complete bone evaluation. RESULTS AND CONCLUSIONS: Hip bone mass density (BMD) values are the main risk factor for osteoporotic fractures in both genders. These values are comparable when expressed in terms of volumetric density. In women, risk factors that determine the appearance of fractures are previous non-traumatic fractures when they are older than 50 years, total hip BMD, serum calcium levels and thiazide intake while in men only total hip BMD reaches statistical significance.

Application of change-point problem to the detection of plant patches.

In ecology, if the considered area or space is large, the spatial distribution of individuals of a given plant species is never homogeneous; plants form different patches. The homogeneity change in space or in time (in particular, the related change-point problem) is an important research subject in mathematical statistics. In the paper, for a given data system along a straight line, two areas are considered, where the data of each area come from different discrete distributions, with unknown parameters. In the paper a method is presented for the estimation of the distribution change-point between both areas and an estimate is given for the distributions separated by the obtained change-point. The solution of this problem will be based on the maximum likelihood method. Furthermore, based on an adaptation of the well-known bootstrap resampling, a method for the estimation of the so-called change-interval is also given. The latter approach is very general, since it not only applies in the case of the maximum-likelihood estimation of the change-point, but it can be also used starting from any other change-point estimation known in the ecological literature. The proposed model is validated against typical ecological situations, providing at the same time a verification of the applied algorithms.

[Need of hepatic bipartition or split in the transplant in children]. / Necesidad de la bipartición hepática o split en el trasplante en niños.

AIM: To analyze the benefits of Split (for adult and for child) in liver transplantation. PATIENT/METHODS: 1) Analysis of the waiting list mortality estimated on 228 inclusions for transplant since January 2004 to December 2008.2) Impact of the variant techniques (living-related donor and split) on the waiting list mortality in our patients. 3) Analysis of the outcome of 33 split livers which allowed to perform 66 transplants (1994-2008). RESULTS: Estimated as number of patients by 1,000 candidates by year of exposure, the waiting list mortality was 110 in children older than 5 year old, 180 in children from 2 to 5 year-old, 90 in children between 1 and 2 year-old and 510 in younger than 1 year (p<0.05 for the last group). 36/66 split grafts were implanted by our group. Five grafts were lost, 3 due to retransplantation and 2 due to death. Overall patient/graft survival alter 10 years of follow-up was 94.5% and 85.1%, respectively. The rest of the grafts (n=30), were used in other hospitals, and 4 were lost in the early postoperative period. Since the beginning of the study, 85.4% of children between 1 and 2 years, received a living-donor or a split graft, as only 59.9% in the younger than 1 year-old group. CONCLUSION: Our results absolutely justify the ethics of split liver transplantation for an adult and a child. Despite other factors, the benefits of the variant techniques in the 1-2 year-old group are obvious. Up to 60% optimization with these techniques in children younger than 1 year would not be yet enough in order to decrease the mortality waiting list down to that of the rest of the groups.

[Intestinal transplant: in what phase are we?]. / Trasplante intestinal: ¿en qué fase estamos?

OBJECTIVE: To analyze the evolution of Small Bowel Transplantation program since the beginning of the program. MATERIAL AND METHODS: [corrected] All children who underwent intestinal transplantation between 1997 and 2009 were retrospectively reviewed: epidemiological data, status before transplant, surgical technique, immunosupression, results, survival and long.term quality of life were analysed. RESULTS: Fifty-two intestinal transplants were performed in 46 children (20 isolated bowel, 20 combined liver and intestine, and 12 multivisceral); median age was 32m (range 7m-19a); weight 12,3 kg (range 3,9-60); 31 had short gut syndrome, 8 dismotility, 5 intractable diarrhea, and two were miscellaneous. Intestinal adaptation was initially attempted in 26 patients, without success, 20 were directly listed for transplant. The modality of transplant was modified in 17 while listed. Baseline immunosupression consisted of tacrolimus and steroids, although 5 required conversion to Sirolimus later. Six died during the first month, due to sepsis/multiorganic failure (poor status at transplant); 13 died during the long-term follow-up. Acute rejection was seen in 20, chronic rejection in 3, PTLD in 8 (6 died) and GVHD in 5 patients (3 died). Overall survival after 5 years of follow-up is 65,2 % (51,7% for the graft). From 2006 to 2008, overall patient/graft survival at 6 m, 1 and 3 years after transplant is 88,7/84,1, 81,2/81,2 and 81,2/71,1%, respectively. After a median follw-up of 39 +/- 29 months, 27 patients are alive (59%), off TPN, (70% had their ostomy taken down), go to school, are scarcely hospitalized and enjoy a good quality of life. CONCLUSIONS: Intestinal transplantation has consolided itself as a good choice for irreversible intestinal failure, being feasible to achieve a normal life. Although overall survival diminishes over time, the center experience has improved the results. These patients need a very close follow-up, once transplant is over, in order to get an early diagnose of immunological complications.

A predictive survival model for patients with head and neck squamous cell carcinoma treated with immune check point inhibitors.

BACKGROUND: ICIs have expanded treatment options for HNSCC. A minority of the patients respond to these expensive treatments. PATIENTS AND METHODS: This is a single institutional retrospective review on 121 unresectable or metastatic HNSCC patients treated with ICIs. We predicted that inflammatory markers available through routine blood work, in addition to clinical characteristics may divide patients into groups more or less likely to respond to these agents. Here we develop and internally validate our nomogram to predict survival in patients treated with ICIs.

Incidence, morbidity and mortality of hip fractures over a period of 20 years in a health area of Southern Spain.

OBJECTIVE: To evaluate the incidence of osteoporotic hip fracture in the Macarena Health Area (Seville). SETTING AND PARTICIPANTS: This was a prospective observational study that collected all osteoporotic hip fractures that occurred between March 2013 and February 2014 at the Clinical Unit of Traumatology and Orthopaedics. All cases collected during the first 6 months of the study were followed for 1 year after the occurrence of the event. OUTCOME MEASURES: We evaluated the incidence of osteoporotic hip fractures in the Macarena Health Area (Seville) from 1 March 2013 to 28 February 2014, and we compared the incidence with that in 2 previous studies carried out with the same methodology in 1994 and 2006. Furthermore, we calculated the morbidity and degree of disability 1 year after the fracture occurred and determined mortality and the associated factors. RESULTS: The overall incidence was 228 per 100 000 individuals/year (95% CI 204.5 to 251.6), and the incidence was higher in women than in men. In women, the incidence rate decreased in all age groups over time, while in men, the incidence rate increased. The mortality rate 1 year after the episode was 27.2%. The factors associated with overall mortality were a body mass index below 25 kg/m2, renal failure and low plasma proteins. CONCLUSIONS: Our results show a high incidence of osteoporotic hip fracture that is increasing in men, and in men it is associated with a higher mortality than in women. There is room to improve the modifiable factors associated with mortality and the available rehabilitation interventions to reduce the disability associated with these fractures.

[Liver transplant from living donor]. / Trasplante hepático de donante vivo.

AIM: Even though Spain has the highest donation rate in the world, our needs cannot be satisfied, specially in younger children. Living-related donor transplant is an alternative in those cases. PATIENTS AND METHOD: We performed a retrospective study of 57 living-related donor transplants performed in our hospital between June 1993 and December 2007. Median age and weight were 1.2 years old (0.5-14.8) and 8.5 kg (5-62). Indications for transplant were as follow: biliary atresia in 42 cases (73.7%), hepatic tumor in 8 (14%) and others in 7 patients. Type of graft was: monosegment (n=1), left lateral segment (n=45), extended left lateral segment (n=5), left liver (n=4), right liver (n=2). We studied the following factors: graft and patient survival (Kaplan Meier), perioperative conditions, complications, causes of graft lost, donor complications and technique difficulties. RESULTS: Patient survival at 3 months, 1 year, 5 years and 10 years was 98.2%, 98.2%, 95% and 95% respectively. Three grafts werelost due to arterial thrombosis, two due to rejection, one due to portal thrombosis and three due to other causes. Complications were as follow: biliary fistula in the cut surface (6), biliary anastomosis complications (6), cut surface abcess (1), portal stenosis (2), suprahepatic stenosis (1) and intestinal perforation (2). Most common complication in donors was biliary leak (4). Among the technique difficulties, 8 patients needed major reconstruction of suprahepatic vein; 4 needed complex portal reconstruction, 6 patients had double biliary tract and 4 patients needed multiple arterial anastomosis. Wall closure was delayed (Goretex) in 35% of cases (20). CONCLUSIONS: Despite technical complications, results after living-related donor transplantation are excellent. It is particularly favourable for children with low weight, since Spanish policy for organ allocation does not make easy to find an adecuate donor in short periods of time. Without living-related donor transplantations, mortality pretransplant would be much higher.

Monitoring environmental change in an ecosystem.

The monitoring and analysis of the processes taking place in an ecosystem is a key issue for a sustainable human activity. A system of populations, as the biotic component of a complex ecosystem is usually affected by the variation of its abiotic environment. Even in nearly natural ecosystems an abiotic effect like climatic implications of global warming may cause important changes in the dynamics of the population system. In ecosystems involving field cultivation or any industrial activity; the abiotic parameter in question may be the concentration of a substance, changing, e.g. as a result of pollution, application of a pesticide, or a fertilizer, etc. In many cases the observation of the densities of each population may be technically complicated or expensive, therefore the question arises whether from the observation of the densities of certain (indicator) populations, the whole state process of the population system can be uniquely recovered. The paper is aimed at a methodological development of the state monitoring, under the conditions of a changing environment. It is shown, how the technique of mathematical systems theory can be applied not only for the approximate calculation of the state process on the basis of the observed data, even under the effect of an exogene abiotic change with known dynamics; but in certain cases, also for the estimation of the unknown biological effect of the change of an abiotic parameter. The proposed methodology is applied to simple illustrative examples concerning a three-species predator-prey system.

Variant techniques for liver transplantation in pediatric programs.

INTRODUCTION: Several variant techniques have been developed as alternatives to whole liver transplantation to improve size matching, timing, or simply to increase the pool of donors. The aim of this study was to assess the requirements of these techniques and their outcomes in a pediatric transplant program. PATIENTS AND METHOD: A retrospective analysis of children on the waiting list in the last 4 years was carried out. Data of patients who died while on the waiting list (WL) were recorded. Transplanted patients were divided according to the type of graft: whole liver, split, living donor and reduced liver. The analyzed outcome variables were: age, weight, UNOS status, cause of liver failure, complications and graft and patient survival. Comparisons between types of graft were performed by using Kaplan-Meier, log-rank, chi (2) and Kruskal-Wallis tests. RESULTS: During the period studied, 116 children were listed for liver transplantation. Of these 116 children, nine (7.7 %) died after a mean period of 40.5 (5-175) days waiting for a suitable graft. Their median age at inclusion was 214 (35-1607) days, and median weight was 7.2 (12.3-3.6) kg. The cause of liver failure in this group was: 1 hemochromatosis, 1 hepatoblastoma, 2 biliary atresia, 2 acute liver failure, 2 primary non-function (PNF) and 1 chronic rejection. Liver transplantation was performed in 103 children: 25 (24 %) whole livers, 17 (16.5 %) split, 29 (28 %) living donor, 32 (31 %) reduced and 4 remain on the waiting list. Recipient age and weight were significantly lower in those receiving split and living donor than in those who given whole livers. Patient and graft survival were similar in all groups although there was a trend to lower graft survival in patients receiving whole livers. More than 50 % of patients with UNOS status I received a split graft and 5/6 children with hepatoblastoma underwent living donor transplantation. There were no differences in the rate of acute vascular complications, but long-term biliary complications were more frequent in split and living donor grafts. CONCLUSIONS: As long as the goal of zero mortality for children on the waiting list is not achieved, variant techniques will be necessary in pediatric liver transplantation programs. Split and living donor were employed mostly to treat younger children and particularly those with a higher UNOS status. Children with tumors were treated mainly with living donor grafts. Variant techniques, which are absolutely necessary in a pediatric program, need to be improved in order to avoid long-term biliary complications.

Monitoring in a Lotka-Volterra model.

The problem of monitoring arises when in an ecosystem, in particular in a system of several populations, observing some components, we want to recover the state of the whole system as a function of time. Due to the difficulty to construct exactly this state process, we look for an auxiliary system called an observer. This system reproduces this process with a certain approximation. This means that the solution of the observer tends to that of the original system. An important concept for this work is observability. This means that from the observation it is possible to recover uniquely the state process, however, without determining a constructive method to obtain it. If observability holds for the original system, it guarantees the existence of an auxiliary matrix that makes it possible to construct an observer of the system. The considered system of populations is described by the classical Lotka-Volterra model with one predator and two preys and the construction of its observer is illustrated with a numerical example. Finally, it is shown how the observer can be used for the estimation of the level of an abiotic effect on the population system.

Surgery of liver tumors in children in the last 15 years.

AIM: Aim of the study was to review our experience in the management of liver tumors in children over the last 15 years. PATIENTS AND METHODS: A cohort of 78 children with liver tumors managed in our institution between 1991 and 2006 was retrospectively reviewed. There were 45 males and 33 females with a mean age of 32 +/- 41 months at diagnosis. Most tumors were malignant (n = 57); the most frequently occurring tumor was hepatoblastoma (n = 47), followed by hepatocarcinoma (n = 5), sarcoma (n = 4), and lymphoma (n = 1). Vascular tumors (n = 12) predominated among the benign tumors followed by mesenchymal hamartoma (n = 4), focal nodular hyperplasia (n = 3), adenoma (n = 1), and inflammatory pseudotumor (n = 1). We reviewed the epidemiologic features, clinical presentation, diagnosis, treatment and outcomes. We employed MRI and angio-CT for SIOPEL PRETEXT staging and selected the management accordingly for malignant tumors. We analyzed the long-term survival using Kaplan-Meier curves. RESULTS: Benign tumors had an excellent outcome with both medical or surgical management. Of the malignant tumors 4 were PRETEXT I and were treated by left lateral segmentectomy with 100 % survival; 20 were PRETEXT II (12 left and 8 right lobe) and were treated by lobectomy of the corresponding side, except for 1 case which required OLT (90 % survival); 9 children had PRETEXT III tumors requiring trisegmentectomy or extended lobectomies with OLT in 1 case (77.7 % survival). Fourteen children had PRETEXT IV tumors: 10 received OLT and 9 of them are still alive (64.2 % survival). Overall survival was 80.8 %, and actuarial survival at 6 years was 82.2 %. Other malignant tumors had variable results. CONCLUSIONS: Outcomes have improved much in the last years. Surgical removal is necessary in most cases. Transplantation is a very useful adjunct. Treatment of these tumors should be concentrated in centers with expertise.

[Liver transplatation for malignant tumors in children]. / Trasplante hepático en tumores malignos en el niño.

OBJECTIVE: To analyse our results on liver transplantation (LTX) in primitive malignant unresectable liver tumours in children and discussing its controversial indications in order to our experience. METHODS/PATIENTS: We report 12 patients with ages ranging from 6 months to 14 years old. They had hepatoblastoma (11) and fibrolamellar hepatocelullar carcinoma (1) without cirrhosis. LTX was considered as primary treatment in 10 patients (PRETEXT IV or any grade if extension to retrohepatic cava vein, 3 hepatic veins or porta vein were assessed) and as rescue therapy after recurrence (1) or persistence of unresectable macroscopic rests (2). One of the patients who underwent a LTX as primary therapy had lung metastases previously resolved with chemotherapy. We used entire liver (5), left lateral segment from cadaveric donor (3), live related donor (3, 2 segments II-III and 1 right liver) and left lateral segment from split (1). All children received chemotherapy prior and post-transplantation following SIOPEL protocol. OUTCOMES ANALYSED: Procedure tolerance, survival, recurrence rate, disease-free period and risk factors for adverse evolution. RESULTS: All patients overcame the LTX and no early loss of the graft was assessed. 2 patients died because of tumoral relapse, 1 after primary LTX and 1 after rescue LTX (survival rate of both groups 90% vs 50%). Graft and patients 1-year, 3-year, 5-year and 14-year survival were 91%, 91%, 82% and 82% respectively. The boy who presented lung metastases developed new ones one year after LTX that were removed and he actually is free of disease. The disease-free period has a probability for 1, 3 and 5 years of 91%, 75% and 75%. Tumoral tissue persistence is the only risk factor for an adverse evolution in our series. CONCLUSIONS: LTX is possible therapeutic approach for unresectable malignant liver tumours. It provides better results as a primary treatment than as a rescue one, being these outcomes comparable to those from resectable tumours. A right staging and referring patients to an expertise centre contribute to optimize results. LTX for patients presenting with lung metastases could be a controversial option. Live-related donor transplantation is an excellent alternative to avoid disease progression during cadaveric waiting list.