Disparities in time to treatment initiation for rectal cancer patients: an analysis of demographic and socioeconomic factors.

Background: This study investigated demographic and socioeconomic factors contributing to disparities in the time to treatment for rectal cancer. Subgroup analysis based on age < 50 and ≥ 50 was performed to identify differences in time to treatment among young adults (age < 50) compared to older adults with rectal cancer. Methods: An analysis was performed using data from the National Cancer Database, spanning from 2004 to 2019. The study encompassed 281,849 patients diagnosed with rectal cancer. We compared time intervals from diagnosis to surgery, radiation, and chemotherapy, considering age, sex, race, and socioeconomic variables. Analyses were performed for the entire cohort and for two subgroups based on age (< 50 and ≥ 50). Results: Overall, Hispanic patients experienced longer times to surgery, radiation, and chemotherapy compared to non-Hispanic patients (surgery: 94.2 vs. 79.1 days, radiation: 65.0 vs. 55.6 days, chemotherapy: 56.4 vs. 47.8 days, all p < 0.001). Patients with private insurance had shorter times to any treatment (32.5 days) compared to those with government insurance or no insurance (30.6 and 32.5 days, respectively, p < 0.001). Black patients experienced longer wait times for both radiation (63.4 days) and chemotherapy (55.2 days) compared to White patients (54.9 days for radiation and 47.3 days for chemotherapy, both p < 0.001). Interestingly, patients treated at academic facilities had longer times to treatment in surgery, radiation, and chemotherapy compared to those treated at comprehensive and community facilities. When analyzed by age, many of the overall differences persisted despite the age stratification, suggesting that these disparities were driven more by demographic and socioeconomic variables rather than by age. Conclusion: Significant differences in the time to treatment for rectal cancer have been identified. Hispanic patients, individuals lacking private insurance, Black patients, and patients receiving care at academic facilities had the longest times to treatment. However, these differences were largely unaffected by the age (< 50 and ≥ 50) subgroup analysis. Further investigation into the causes of these disparities is warranted to develop effective strategies for reducing treatment gaps and enhancing overall care for rectal cancer patients.

Early Stage Breast Cancer: Does Histologic Subtype (Ductal vs. Lobular) Impact 5 Year Overall Survival?

Histology is an important predictor of the behavior of breast cancer. We aim to study the impact of histology on the overall survival (OS) of breast cancer patients. We studied 11,085 breast cancer patients diagnosed with T1-T2 tumors, clinically node-negative and non-metastatic, from 2004 to 2019 included in the National Cancer Database. Kaplan-Meier curves, log-rank tests and Cox regression models were used to study the impact of histology and other variables on OS. In our patient population, 8678 (78.28%) had ductal cancer (IDC), while 2407 (21.71%) had lobular cancer (ILC). ILC patients were significantly more likely to be older, Caucasian, have a lower grade at diagnosis and be hormone receptor-positive compared to IDC patients. There was no statistically significant difference in the 5-year OS of early stage ductal (16.8%) and lobular cancer patients (16.7%) (p = 0.200). Patients of Hispanic and African American origin had worse OS rates compared to non-Hispanic and Caucasian patients, respectively. For node-positive disease, HER2+ tumors and triple-negative tumors, chemotherapy had a positive influence on OS (HR 0.85, 95% CI 0.77-0.93, p = 0.0012). Histology did not have a significant impact on the 5-year OS of early stage breast cancer patients.

Time to treatment disparities in gastric cancer patients in the United States of America: a comprehensive retrospective analysis.

Introduction: Gastric cancer ranks as the 5th most prevalent cancer and the 4th leading cause of cancer-related deaths worldwide. Various treatment modalities, including surgical resection, chemotherapy, and radiotherapy, are available for gastric cancer patients. However, disparities related to age, sex, race, socioeconomic factors, insurance status, and demographic factors often lead to delayed time to treatment. Methods: In this retrospective study, conducted between 2004 and 2019, we utilized data from the National Cancer Database (NCDB) to investigate the factors contributing to disparities in the time to first treatment, surgery, chemotherapy, and radiotherapy among gastric cancer patients. Our analysis incorporated several variables, and statistical analysis was conducted to provide valuable insights into these disparities. Results: We observed notable disparities in the timing of treatment for various demographic groups, including age, sex, race, insurance status, geographic location, and facility type. These disparities include longer time to treatment in males (32.67 vs 30.75), Native Americans (35.10 vs 31.09 in Asians), low-income patients (32 vs 31.15), patients getting treatment in an academic setting (36.11 vs 29.61 in community setting), significantly longer time to chemotherapy in 70+ age group (51.13 vs 40.38 in <40 y age group), black race (55.81 vs 47.05 in whites), low income people (49.64 vs 46.74), significantly longer time to radiotherapy in females (101.61 vs 79.75), blacks and Asians (109.68 and 113.96 respectively vs 92.68 in Native Americans) etc. There are various other disparities in time to surgery, chemotherapy, and radiotherapy. Conclusions: Understanding these disparities is crucial in developing targeted strategies to improve timely access to appropriate treatments and enhance outcomes for gastric cancer patients. Future research with updated data and prospective study designs can provide a more comprehensive understanding of the factors influencing patient outcomes in gastric cancer.

Estado nutricional y riesgo cardiovascular en el personal que labora dentro de un campus universitario / Nutritional status and cardiovascular risk in staff who work within a university campus

Introducción: El personal que labora en las universidadespodría constituir un grupo vulnerable de padecer enfermeda-des cardiovasculares, debido a los cambios constantes en elestilo de vida, como las rutinas de trabajo acelerado, largasjornadas sentados frente a un computador e inadecuados há-bitos alimentarios. Objetivo: Evaluar el estado nutricional y riesgo cardiovascu-lar del personal que labora dentro de un campus universitario. Materiales y Métodos: Estudio transversal, descriptivo yobservacional. Se recogió información sobre el estilo de vidacomo la ingesta de alcohol, consumo de cigarrillos y prácticade actividad física. Para identificar los hábitos alimentarios seaplicó una encuesta validada de frecuencia de consumo dealimentos. El riesgo cardiovascular se lo pudo establecer me-diante los puntos de corte de la circunferencia cintura, índicecintura/altura e índice cintura/cadera.Resultados: La muestra de investigación estuvo consti-tuida por 112 varones y 217 mujeres que representaron el34% y 66% respectivamente. El mayor porcentaje de investi-gados expresaron no ingerir alcohol (55,0%), no consumir ci-garrillos (90,0%) y, no realizar ningún tipo de actividad físicadiaria (52,6%). Se encontró una ingesta insuficiente en todoslos grupos de alimentos. El riesgo cardiovascular medido através de la circunferencia cintura arrojó un riesgo alto(25,8%) y muy alto (41,6%). Por otra, mediante el uso del ín-dice cintura/altura, se evidenció que el 99,1% de los investi-gados presenta riesgo cardiovascular. Finalmente, a través delíndice cintura/cadera se encontró un riesgo elevado (34,3) ymuy elevado (27,7%). Conclusiones: El riesgo cardiovascular determinado a tra-vés de perímetros e índices antropométricos en la poblaciónuniversitaria investigada fue alta.(AU)

Introduction: Staff working in universities could constitutea vulnerable group for suffering from cardiovascular diseases,due to constant changes in lifestyle, such as accelerated workroutines, long days sitting in front of a computer and inadequateeating habits.Objective: To evaluate the nutritional status and cardio -vascular risk of personnel who work within a university campus.Materials and methods:Cross-sectional, descriptive andobservational study. Information was collected on lifestylesuch as alcohol intake, cigarette consumption, and physical activity. To identify eating habits, a validated food consumptionfrequency survey was applied. Cardiovascular risk could beestablished using the cut-off points of waist circumference,waist/height ratio and waist/hip ratio.Results: The research sample consisted of 112 men and217 women, representing 34% and 66% respectively. Thehighest percentage of those investigated expressed notdrinking alcohol (55.0%), not consuming cigarettes(90.0%) and not doing any type of daily physical activity(52.6%). Insufficient intake was found in all food groups.Cardiovascular risk measured through waist circumferenceshowed a high risk (25.8%) and a very high risk (41.6%).On the other hand, through the use of the waist/heightratio, it was shown that 99.1% of those investigatedpresent cardiovascular risk. Finally, through the waist/hipratio, a high (34.3) and very high (27.7%) risk was found.Conclusions:The cardiovascular risk determined throughperimeters and anthropometric indices in the universitypopulation investigated was high. It is recommended toimplement health promotion strategies to prevent theappearance of these pathologies in the long term and, in turn,treat the disease in people who suffer from it, allowing themto improve their quality of life.(AU)

Ibero-Panamerican Federation of Periodontology Delphi study on the trends of periodontology and periodontics by the year 2030. A Latin American consensus.

BACKGROUND AND OBJECTIVE: As elsewhere in the world, the prevalence of periodontitis in stages I-II is high in the Latin American population, this scenario emphasizes the need for identification of urgent needs for allocating adequate resources to provide diagnosis, prevention, and treatment of these diseases. The aim of this Delphi study was to predict the trends in periodontology/periodontics in the Latin American region by the year 2030. METHODS: A steering committee and an advisory group of experts in periodontology/periodontics were selected from 16 countries. An open questionnaire of 60 questions was validated and used following the Delphi methodology. RESULTS: Two hundred and twenty-five experts from Latin America answered the two rounds of the questionnaire. Moderate to strong consensus was reached on 45 questions (75%). The prediction was that the prevalence of gingivitis and periodontitis in stages I and II will be maintained, the importance of the link with systemic diseases will increase, and the impact of prevention and periodontal treatment will also increase, mainly in the private sector. There was a strong consensus that plastic and regenerative surgical procedures will increase, as well as the demand for training in the specialty of periodontology. CONCLUSIONS: The present study has provided relevant and useful information on predictions in periodontology/periodontics in Latin America, with important level of consensus among experts. It has been predicted that periodontitis will still be a highly prevalent disease, and its links with other medical conditions should demand more attention by health authorities to develop adequate prevention and management policies and strategies.

Inequities in Time to Treat Thyroid Cancer.

BACKGROUND/AIM: The purpose of this study was to determine socioeconomic and demographic factors which may contribute to inequities in time to treat thyroid cancer. PATIENTS AND METHODS: We used data from the National Cancer Database, 2004-2019, to conduct an analysis of thyroid cancer patients. All (434,083) patients with thyroid cancer, including papillary (395,598), follicular (23,494), medullary (7,638), and anaplastic (7,353) types were included. We compared the wait time from diagnosis to first treatment, surgery, radiotherapy, and chemotherapy for patients based on age, race, sex, location, and socioeconomic status (SES). RESULTS: A total of 434,083 patients with thyroid cancer were included. Hispanic patients had significantly longer wait times to all treatments compared to non-Hispanic patients (first treatment 33.44 vs. 20.45 days, surgery 40.06 vs. 26.49 days, radiotherapy 114.68 vs. 96.42 days, chemotherapy 92.70 vs. 58.71 days). Uninsured patients, patients at academic facilities, and patients in metropolitan areas also had the longest wait times to treatment. CONCLUSION: This study identified multiple disparities related to SES and demographics that correspond to delays in time to treatment. It is crucial that this topic is investigated further to help mitigate these incongruities in thyroid cancer care in the future.

Sociodemographic Barriers to the Timely Treatment of Pancreatic Cancer.

BACKGROUND/AIM: Pancreatic cancer has a high mortality rate and timely treatment is imperative for favorable patient outcomes. This retrospective study aimed to identify disparities in time to treatment for pancreatic cancer based on sociodemographic factors. PATIENTS AND METHODS: The study used the National Cancer Database from 2004 to 2019. A total of 423,482 patients with pancreatic cancer were included in the study. Time to first treatment, surgery, radiation, and chemotherapy were analyzed in the context of age, sex, race, Hispanic origin, insurance status, income, facility type, geographic setting, grade, stage, and Charlson-Deyo Comorbidity score (CDC). RESULTS: All sociodemographic factors included were found to be significantly associated with disparities for time to treatment in at least one of the categories studied. Minorities, treatment at academic facilities, and patients with a high CDC score had consistently longer times to all treatment classifications. CONCLUSION: The analyzed sociodemographic factors affected time to pancreatic cancer treatment. Disparities in time to treatment for pancreatic cancer must be studied and understood to ameliorate the impact this cancer has on society and assure the best possible care for all communities.

Disparities in Time to Treatment for Skin Cancer.

BACKGROUND/AIM: Skin cancer is the most common cancer worldwide. This study aimed to identify factors contributing to the disparities in skin cancer treatment. PATIENTS AND METHODS: Data from The National Cancer Database (NCDB) spanning 2004 to 2019 were utilized. Variables including age, sex, race, Hispanic origin, Charlson-Deyo Comorbidity (CDC) score, geographic location, insurance status, income, grade and stage of cancer, and type of treatment facility impacting the time to treatment, surgery, radiation, and chemotherapy were analyzed. RESULTS: Trends of longer time to treatment were seen with older age, non-Hispanic white, uninsured, those with a higher CDC score, and treated at academic facilities. Additionally, annual income and clinicopathology of cancer were also significantly associated with time to treatment. CONCLUSION: Our findings contribute to the expanding body of evidence pointing to the influence of socioeconomic and demographic factors in treatment disparities across diverse patient populations.

Autoimmune Hemolytic Anemia Caused by Cold Agglutinin Antibodies in Systemic Lupus erythematosus-a Rare Association: Case Report.

Autoimmune hemolytic anemias (AIHAs) are rare and heterogeneous disorders characterized by the destruction of red blood cells by warm or cold antibodies. Hemolytic anemia associated with warm antibodies is the most common, whereas cold antibodies are rare and infrequent in cases published in the scientific literature. Herein, we present the case of a young patient with systemic lupus erythematosus (SLE) and autoimmune hemolytic anemia caused by cold antibodies. Initially, infectious etiology and hematological malignancy were considered, which were ruled out. She required management in the intensive care unit due to severe hematological involvement and responded well to immunomodulatory therapy. This case illustrates the importance of a strong clinical suspicion of AIHA due to cold agglutinins associated with SLE when faced with similar clinical symptoms in order to achieve a timely diagnosis and provide optimal therapy.

Impact of vaccination against COVID-19 on patients with cancer in ACHOC-C19 study: Real world evidence from one Latin American country.

Introduction: During the pandemic, it has been recommended that vaccination against COVID-19 be a priority for patients with cancer; however, these patients were not included in the initial studies evaluating the available vaccines. Objective: To define the impact of vaccination against COVID-19 in preventing the risk of complications associated with the infection in a cohort of patients with cancer in Colombia. Methods: An analytical observational cohort study, based on national registry of patients with cancer and COVID 19 infection ACHOC-C19, was done. The data was collected from June 2021, until October 2021. Inclusion criteria were: Patients older than 18 years with cancer diagnosis and confirmed COVID-19 infection. Data from the unvaccinated and vaccinated cohorts were compared. Outcomes evaluated included all-cause mortality within 30 days of COVID-19 diagnosis, hospitalization, and need for mechanical ventilation. The estimation of the effect was made through the relative risk (RR), the absolute risk reduction (ARR) and the number needed to treat (NNT). Multivariate analysis was performed using generalized linear models. Results: 896 patients were included, of whom 470 were older than 60 years (52.4%) and 59% were women (n=530). 172 patients were recruited in the vaccinated cohort and 724 in the non-vaccinated cohort (ratio: 1 to 4.2). The cumulative incidence of clinical outcomes among the unvaccinated vs vaccinated patients were: for hospitalization 42% (95% CI: 38.7%-46.1%) vs 29%; (95% CI: 22.4%-36.5%); for invasive mechanical ventilation requirement 8.4% (n=61) vs 4.6% (n=8) and for mortality from all causes 17% (n=123) vs 4.65% (n=8). Conclusion: In our population, unvaccinated patients with cancer have an increased risk of complications for COVID -19 infection, as hospitalization, mechanical ventilation, and mortality. It is highly recommended to actively promote the vaccination among this population.

Clinical Outcomes and Prognostic Factors of Patients With Early Malignant Melanoma in One Latin American Country: Results of the Epidemiological Registry of Malignant Melanoma in Colombia Study.

To describe the population with early malignant melanoma, we performed a cohort study on the basis of the Epidemiological Registry of Malignant Melanoma in Colombia-Asociacion Colombiana de Hematologia y Oncologia. From January 2011 until December 2021, 759 patients were included; the average age was 66 years, 57% were women, acral lentiginous histology was found in 27.8% of patients, and the median follow-up was 36.5 months. The prognostic factors for overall survival in our population are Eastern Cooperative Oncology Group 3-4 (hazard ratio [HR], 13.8), stage III (HR, 5.07), received radiotherapy (HR, 3.38), ulceration on histology (HR, 2.68), chronic sun exposure (HR, 2.3), low income (HR, 2.04), previous local surgery (HR, 0.27), and have received adjuvant treatment (HR, 0.41).

Association Between Hyponatremia and Maintenance Intravenous Solutions in Critically Ill Children: A Retrospective Observational Study.

Objetive: We sought to determine the association between maintenance intravenous solutions and the presence of hyponatremia in children in pediatric intensive care (PICU). Materials and Methods: An analytical observational study in children hospitalized in the PICU between January 2015 and December 2018. Patients who received maintenance fluids within the first 48 h after admission and who had at least two serum sodium levels drawn during this time were included. Measurements and Main Results: A total of 1,668 patients were admitted to the PICU during the study period, 503 of whom met the inclusion criteria. The median age was 24 months (IQR 8-96) and 50.9% were female. Altogether, 24.1% of the children developed hyponatremia; it was more frequent in those who received hypotonic solutions (63 vs. 37%; OR 1.41 95% CI 0.92, 2.15 p = 0.106), who also had a longer hospital stay (20 vs. 14 days, difference in means 8 days, 95% CI 2.67, 13.3, p = 0.001). Children who received loop diuretics and those who were post-operative had a greater risk of developing hyponatremia if they received hypotonic solutions (aOR 2.1 95% CI 1.41, 3.0, p = 0.000). Those with balanced isotonic solutions had a lower risk of developing hyponatremia (aOR 0.59 95% CI 0.35, 0.99, p = 0.004) and hyperchloremia (aOR 0.51 95% CI 0.34, 0.77, p = 0.000), adjusted for disease severity. A greater risk of death was found in the group with severe hyponatremia <130 mEq/L (aOR 9.75 95% CI 1.64-58.15; p = 0.01). Conclusions: Hyponatremia associated with the use of hypotonic maintenance solutions occurs in one out of four children in intensive care. The use of these solutions is associated with a longer hospital stay, and the main risk groups are post-operative patients and those who receive loop diuretics. Clinical studies are needed to determine which maintenance solutions have the greatest efficacy and safety in critically ill children.

Impact of COVID-19 Infection on Patients with Cancer: Experience in a Latin American Country: The ACHOCC-19 Study.

INTRODUCTION: The ACHOCC-19 study was performed to characterize COVID-19 infection in a Colombian oncological population. METHODOLOGY: Analytical cohort study of patients with cancer and COVID-19 infection in Colombia. From April 1 to October 31, 2020. Demographic and clinical variables related to cancer and COVID-19 infection were collected. The primary outcome was 30-day mortality from all causes. The association between the outcome and the prognostic variables was analyzed using logistic regression models and survival analysis with Cox regression. RESULTS: The study included 742 patients; 72% were >51 years. The most prevalent neoplasms were breast (132, 17.77%), colorectal (92, 12.34%), and prostate (81, 10.9%). Two hundred twenty (29.6%) patients were asymptomatic and 96 (26.3%) died. In the bivariate descriptive analysis, higher mortality occurred in patients who were >70 years, patients with lung cancer, ≥2 comorbidities, former smokers, receiving antibiotics, corticosteroids, and anticoagulants, residents of rural areas, low socioeconomic status, and increased acute-phase reactants. In the logistic regression analysis, higher mortality was associated with Eastern Cooperative Oncology Group performance status (ECOG PS) 3 (odds ratio [OR] 28.67; 95% confidence interval [CI], 8.2-99.6); ECOG PS 4 (OR 20.89; 95% CI, 3.36-129.7); two complications from COVID-19 (OR 5.3; 95% CI, 1.50-18.1); and cancer in progression (OR 2.08; 95% CI, 1.01-4.27). In the Cox regression analysis, the statistically significant hazard ratios (HR) were metastatic disease (HR 1.58; 95% CI, 1.16-2.16), cancer in progression (HR 1.08; 95% CI, 1.24-2.61) cancer in partial response (HR 0.31; 95% CI, 0.11-0.88), use of steroids (HR 1.44; 95% CI, 1.01-2.06), and use of antibiotics (HR 2.11; 95% CI, 1.47-2.95). CONCLUSION: In our study, patients with cancer have higher mortality due to COVID-19 infection if they have active cancer, metastatic or progressive cancer, ECOG PS >2, and low socioeconomic status. IMPLICATIONS FOR PRACTICE: This study's findings raise the need to carefully evaluate patients with metastatic cancer, in progression, and with impaired Eastern Cooperative Oncology Group status to define the relevance of cancer treatment during the pandemic, consider the risk/benefit of the interventions, and establish clear and complete communication with the patients and their families about the risk of complications. There is also the importance of offering additional support to patients with low income and residence in rural areas so that they can have more support during cancer treatment.

Delphi Project on the trends in Implant Dentistry in the COVID-19 era: Perspectives from Latin America.

AIM: To establish trends in Implant Dentistry in Latin America in the COVID-19 pandemic. MATERIAL AND METHODS: A steering committee and an advisory group of experts in Implant Dentistry were selected among eighteen countries. An open-ended questionnaire by Delphi methodology was validated including 64 questions, divided in 7 topics, concerning the various trends in dental implantology. The survey was conducted in two rounds, which provided the participants in the second round with the results of the first. The questionnaires were completed on August 2020, and the online meeting conference was held on September 2020. The final prediction was developed through consensus by a selected group of experts. RESULTS: A total of 197 experts from Latin America answered the first and second questionnaire. In the first round, the established threshold for consensus (65%) was achieved in 30 questions (46.87%). In the second round, performed on average 45 days later, this level was achieved in 47 questions (73.43%). Consensus was completely reached on the item "Diagnostic" (100%), the field with the lowest consensus was "Demand for treatment with dental implants" (37.5%). CONCLUSIONS: The present study in Latin America has provided relevant and useful information on the predictions in the education and practice of Implant Dentistry in the COVID-19 era. The consensus points toward a great confidence of clinicians in the biosecurity protocols used to minimize the risk of SARS-CoV-2 transmission. It is foreseen as an important change in education, with introduction of virtual reality and other simulation technologies in implant training.

Chronic whipworm infection exacerbates Schistosoma mansoni egg-induced hepatopathology in non-human primates.

BACKGROUND: Schistosomiasis continues to inflict significant morbidity and mortality in the tropical and subtropical regions of the world. The disease endemicity overlaps with the transmission of other parasitic diseases. Despite the ubiquity of polyparasitism in tropical regions, particularly in rural communities, little is known about the impact of multiple helminth infections on disease progression. In this pilot study, we describe the influence of chronic Trichuris trichiura infection on Schistosoma mansoni egg-induced hepatopathology in infected baboons. METHODS: Baboons with or without underlying whipworm infection were challenged with S. mansoni cercariae to establish schistosomiasis. Adult S. mansoni worms were recovered by perfusion and enumerated, hepatic granulomas were quantified via light microscopy, and transcriptional profiling of tissues were completed using RNA sequencing technologies. RESULTS: Co-infection with both S. mansoni and T. trichiura resulted in higher female schistosome worm burden and significantly larger liver granuloma sizes. Systems biology analyses of peripheral blood mononuclear cells (PBMC) revealed pathways associated with increased liver damage in co-infected baboons. CONCLUSIONS: Underlying chronic whipworm infection intensified schistosome egg-induced liver pathology in infected baboons. RNA-Seq analysis provided insight into pathways associated with increased liver damage, corroborating histological findings.

Treatment for Malignant Pheochromocytomas and Paragangliomas: 5 Years of Progress.

PURPOSE OF REVIEW: The purpose of this manuscript is to review the progress in the field of therapeutics for malignant pheochromocytomas and sympathetic paraganglioma (MPPG) over the past 5 years. RECENT FINDINGS: The manuscript will describe the clinical predictors of survivorship and their influence on the first TNM staging classification for pheochromocytomas and sympathetic paragangliomas, the treatment of hormonal complications, and the rationale that supports the resection of the primary tumor and metastases in patients with otherwise incurable disease. Therapeutic options for patients with bone metastasis to the spine will be presented. The manuscript will also review chemotherapy and propose a maintenance regimen with dacarbazine for patients initially treated with cyclophosphamide, vincristine, and dacarbazine. Finally, the manuscript will review preliminary results of several phase 2 clinical trials of novel radiopharmaceutical agents and tyrosine kinase inhibitors. MPPGs are very rare neuroendocrine tumors. MPPGs are usually characterized by a large tumor burden, excessive secretion of catecholamines, and decreased overall survival. Recent discoveries have enhanced our knowledge of the pathogenesis and phenotypes of MPPG. This knowledge is leading to a better understanding of the indications and limitations of the currently available localized and systemic therapies as well as the development of phase 2 clinical trials for novel medications.

Current and future treatments for malignant pheochromocytoma and sympathetic paraganglioma.

Pheochromocytomas (PHs) and sympathetic paragangliomas (SPGs) are rare neuroendocrine tumors. Approximately 17 % of these tumors are malignant, but because no molecular or histologic markers for malignancy exist, patients are often diagnosed with malignant PHs or SPGs after unresectable disease has formed. Patients with progressive metastatic tumors and overwhelming symptoms are currently treated with systemic chemotherapy and radiopharmaceutical agents such as metaiodobenzylguanidine. These therapies lead to partial radiographic response, disease stabilization, and symptomatic improvement in approximately 40 % of patients, and systemic chemotherapy is associated with a modest improvement in overall survival duration. However, over the past decade, substantial progress has been made in clinical, biochemical, and radiographic diagnosis of PHs and SPGs. Approximately 50 % of patients with malignant PHs and SPGs have been found to carry hereditary germline mutations in the succinate dehydrogenase subunit B gene (SDHB), and anti-angiogenic agents such as sunitinib have been found to potentially play a role in the treatment of malignant disease, especially in patients with SDHB mutations. In some patients, treatment with sunitinib has been associated with partial radiographic response, disease stabilization, decreased fluorodeoxyglucose uptake on positron emission tomography, and improved blood pressure control. These findings have led to the development of prospective clinical trials of new targeted therapies for metastatic disease. Here, we provide an updated review of the clinical and genetic predictors of malignant disease, radiographic diagnosis of malignant disease, and information from the most relevant studies of systemic therapies, as well as proposed treatment guidelines for patients with metastatic or potentially malignant PHs and SPGs.

Limnology in El Dorado: some surprising aspects of the regulation of phytoplankton productive capacity in a high-altitude Andean lake (Laguna de Guatavita, Colombia).

High-altitude mountain lakes remain understudied, mostly because of their relative inaccessibility. Laguna de Guatavita, a small, equatorial, high-altitude crater lake in the Eastern Range of the Colombian Andes, was once of high cultural importance to pre-Columban inhabitants, the original location of the legendary El Dorado. We investigated the factors regulating the primary production in Laguna de Guatavita (4degrees58'50" N - 73degrees46'43" W, alt. 2 935m.a.s.l., area: 0.11km2, maximum depth: 30m), during a series of three intensive field campaigns, which were conducted over a year-long period in 2003-2004. In each, standard profiles of temperature, oxygen concentration and light intensity were determined on each of 16-18 consecutive days. Samples were collected and analysed for chlorophyll and for biologically-significant solutes in GF/F-filtered water (NH4+, NO3(-), NO2(-); soluble reactive phosphorus). Primary production was also determined, by oxygen generation, on each day of the campaign. Our results showed that the productive potential of the lake was typically modest (campaign averages of 45-90mg C/m2.h) but that many of the regulating factors were not those anticipated intuitively. The lake is demonstrably meromictic, reminiscent ofkarstic dolines in higher latitudes, its stratification being maintained by solute- concentration gradients. Light penetration is poor, attributable to the turbidity owing to fine calcite and other particulates in suspension. Net primary production in the mixolimnion of Laguna de Guavita is sensitive to day-to-day variations in solar irradiance at the surface. However, deficiencies in nutrient availability, especially nitrogen, also constrain the capacity of the lake to support a phytoplankton. We deduced that Laguna de Guatavita is something of a limnological enigma, atypical of the common anticipation of a "mountain lake". While doubtlessly not unique, comparable descriptions of similar sites elsewhere are sufficiently rare to justify the presentation of the data from Laguna de Guatavita that our studies have revealed so far.

Limnology in El Dorado: some surprising aspects of the regulation of phytoplankton productive capacity in a high-altitude Andean lake (Laguna de Guatavita, Colombia)

High-altitude mountain lakes remain understudied, mostly because of their relative inaccessibility. Laguna de Guatavita, a small, equatorial, high-altitude crater lake in the Eastern Range of the Colombian Andes, was once of high cultural importance to pre-Columban inhabitants, the original location of the legendary El Dorado. We investigated the factors regulating the primary production in Laguna de Guatavita (4°58’50” N - 73°46’43” W, alt. 2 935m.a.s.l., area: 0.11km², maximum depth: 30m), during a series of three intensive field campaigns, which were conducted over a year-long period in 2003-2004. In each, standard profiles of temperature, oxygen concentration and light intensity were determined on each of 16-18 consecutive days. Samples were collected and analysed for chlorophyll and for biologically-significant solutes in GF/F-filtered water (NH4+, NO3- , NO2-; soluble reactive phosphorus). Primary production was also determined, by oxygen generation, on each day of the campaign. Our results showed that the productive potential of the lake was typically modest (campaign averages of 45-90mg C/m².h) but that many of the regulating factors were not those anticipated intuitively. The lake is demonstrably meromictic, reminiscent of karstic dolines in higher latitudes, its stratification being maintained by solute- concentration gradients. Light penetration is poor, attributable to the turbidity owing to fine calcite and other particulates in suspension. Net primary production in the mixolimnion of Laguna de Guavita is sensitive to day-to-day variations in solar irradiance at the surface. However, deficiencies in nutrient availability, especially nitrogen, also constrain the capacity of the lake to support a phytoplankton. We deduced that Laguna de Guatavita is something of a limnological enigma, atypical of the common anticipation of a “mountain lake”. While doubtlessly not unique, comparable descriptions of similar sites elsewhere are sufficiently rare to justify the presentation of the data from Laguna de Guatavita that our studies have revealed so far.

Los factores que regulan la producción primaria en un lago remoto, pequeño, ecuatorial y de elevada altitud en la región Oriental de los Andes Colombianos (4°58’50” N - 73°46’43” W, altura 2 935m.s.n.m., área 0.11km² y profundidad máxima 30m), que también tuvo importancia cultural para los indígenas precolombinos y los orígenes de la leyenda de El Dorado, fueron investigados. La relativa lejanía del lugar requirió una serie de tres campañas intensivas de estudio, en un periodo de un año (2003-2004). Durante cada campaña se realizaron perfiles temperatura, concentración de oxígeno e intensidad de luz. Se recolectaron muestras para medir la concentración de clorofila y de solutos de significado biológico en agua filtrada GF/F. Cada día de la campaña se llevaron a cabo mediciones de la producción primaria, como se indica por la producción de oxígeno. Estas demostraron que el potencial productivo es particularmente modesto (promedio de campañas de 45-90mgC/m².h, pero casi todos los aspectos de su regulación fueron sorprendentes y contrarios al sentido común. El lago es meromíctico, reminiscencia de dolinas kársticas de latitudes más altas y la estratificación se mantiene por los solutos. La penetración de luz es pobre, atribuible a la alta turbidez debida a la calcita fina y a otras partículas en suspensión. La producción primaria neta del mixolimnion de la Laguna de Guatavita es sensible a las variaciones del día a día de la radiación superficial. Deficiencias en la disponibilidad de nutrientes, sobre todo, del nitrógeno, también limitaron la capacidad productiva del fitoplancton. La laguna de Guatavita es una especie de enigma limnológico: aunque sin duda, no es el único, las descripciones de sitios similares en otras partes son lo suficientemente raras para justificar la presentación de los datos revelados hasta hoy en nuestro estudio.

[Proximal composition, lipid and cholesterol content of meat from pigs fed peach-palm meal (Bactris gasipaes Kunth) and synthetic lysine]. / Composición proximal y contenido de lípidos y colesterol de la carne de cerdos alimentados con harina de pijiguao (Bactris gasipaes Kunth) y lisina sintética.

Two experiments were conducted to evaluate the proximal composition, lipids and cholesterol content of meat from pigs fed diets with peach-palm meal (PPM), with or without addition of synthetic lysine (LYS). In experiment 1, 24 pigs were randomly allotted into six treatments with three levels of PPM (0.16 and 32%) and two levels of LYS (0 and 0.27%). In experiment II, 16 finishing pigs were fed with two levels of PPM (0 and 17.50%) and two levels of LYS (0 and 0.27%). At the end of each experiment (42 and 35 d, respectively), pigs were slaughtered and loin samples were obtained to determine crude protein, dry matter, moisture, ash, total lipids, and cholesterol content. In experiment I, pork loin from 16% PPM had more dry matter (26.45 g/100 g) and less moisture (73.49 g/100g) than pork loin from 32% PPM (25.11 y 75.03 g/100g, respectively). Meat samples from pigs without LYS had higher (p < 0.05) content of lipids (2.11 g/100 g) than meat from pigs that consumed LYS (1.72 g/100 g). In experiment II, the proximal, lipids and cholesterol content were similar among treatments. The PPM addition to pig diets did not affect the proximal composition of pork, while LYS addition indicated a reduction of total lipids, which could result as an alternative to obtain leaner meat.