(Press-News.org) (10 a.m. EDT, June 2, 2021--Denver) - New research published in the Journal of Thoracic Oncology (JTO) suggests the method used to calculate how obesity is measured may affect whether it is considered a risk factor for lung cancer. The JTO is an official journal of the International Association for the Study of Lung Cancer.
Although the association between measures of obesity and both cancer incidence and outcome are clear in some solid tumor types such as breast, esophageal, and colon cancer, the relationship between obesity and lung cancer is more nuanced.
Now, a group of researchers led by Sai Yendamuri, M,D, from Rosewell Comprehensive Cancer Cancer in Buffalo, N.Y., suggests that using traditional methods of measuring obesity, including the body mass index, might be one of the reasons why obesity is not considered a risk factor for lung cancer.
The researchers conducted an examination of patients with lung cancer before they underwent surgery and calculated their excess body weight using visceral fat index measured by CT scans.
"While BMI is easy to measure, its use has been criticized due to its inability to discriminate between fat and lean body mass," Dr. Yendamuri said. "BMI also fails to account for body fat distribution. It is becoming increasingly recognized that 'visceral' or 'central obesity' is the primary driver behind the health outcomes linked to high body fat."
A previous study demonstrated a close correlation between visceral obesity as determined by analysis of a single slice of abdominal CT and a volumetric analysis of visceral fat. This finding demonstrated the feasibility of using such image-based measurements in a large cohort of patients.
"Based on the established knowledge described above, we sought to measure central obesity in a cohort of [patients with] stage I NSCLC [who were] undergoing lobectomy at our institution and examine its association with oncologic outcomes," Joseph Barbi, PhD, first author of the manuscript, reported. Because patients with early stage disease are typically treated with surgery alone, without other treatments that may complicate analysis, the researchers believed they provide a context where the relationship between central obesity and tumor progression can be studied without additional therapy-associated confounders.
Dr. Barbi and colleagues examined 554 patients with stage I and II NSCLC undergoing lobectomy. Of these, reliable fat area measurements were obtained in 513 patients: 499 (97.3 %) at L3, 5 (0.9%) at L2, and 9 (1.8%) at L1. Similarly, 159 patients with advanced-stage NSCLC with molecular testing had reliable fat area measurements: 146 (91.8%) at L3, 10 at L2 (6.3%) and 3 at L1(1.9%). Interobserver correlation of VFI measurements were good (n = 53; R2 = 0.95). Correlation of measurements between L2 and L3 levels (n = 29; R2 = 0.92; Slope = 1.05) and between L1 and L3 levels (n = 28; R2 = 0.85; Slope = 1.05) were also good (Supplementary Figure S1). Therefore, in the few cases where measurements at L3 were not available, measurements at L2 or L1 were used. Importantly, CT scans of these patients could be used to clearly identify individuals with distinctly predominant visceral or subcutaneous adipose tissue distributions.
"These findings clarify the truly negative relationship that exists between central obesity and lung cancer outcomes, and they present a viable alternative to the use of BMI in retrospective studies of obesity rooted in biology with clear relevance to cancer outcomes," Barbi reported.
Taken together, the clinical and preclinical findings suggest a common potential mechanism for the accelerating effect of obesity on the development of tumor burden in the obese -- namely, an apparently multifaceted immune dysfunction prevalent in the tumors of obese mice and patients, the authors report.
"Our study provides much needed clarity to the relationship between adiposity and NSCLC patient survival, providing firm scientific justification for the targeting of obesity's pro-tumor effects, which include decidedly adverse effects on the antitumor immune response," Dr. Yendamuri wrote.
"Our findings also reaffirm the utility and relevance of available mouse models to study further the mechanisms of obesity's lung cancer promoting effects. Importantly, they also validate a refined approached for studying obesity in retrospective data sets [of patients with cancer]," he said.
"Visceral obesity is associated with poor overall and recurrence free survival in patients with early NSCLC, and these findings may inform continued efforts to better predict lung cancer outcomes and management, as well as apply treatments and develop novel therapeutic approaches to prevent or control early-stage lung cancers across a patient pool that is increasingly overweight and obese," according to the study.
INFORMATION:
About the IASLC:
The International Association for the Study of Lung Cancer (IASLC) is the only global organization dedicated solely to the study of lung cancer and other thoracic malignancies. Founded in 1974, the association's membership includes nearly 7,500 lung cancer specialists across all disciplines in over 100 countries, forming a global network working together to conquer lung and thoracic cancers worldwide. The association also publishes the Journal of Thoracic Oncology, the primary educational and informational publication for topics relevant to the prevention, detection, diagnosis, and treatment of all thoracic malignancies. Visit http://www.iaslc.org for more information.
About the JTO:
Journal of Thoracic Oncology (JTO), the official journal of the International Association for the Study of Lung Cancer, is the primary educational and informational publication for topics relevant to the prevention, detection, diagnosis, and treatment of all thoracic malignancies. JTO emphasizes a multidisciplinary approach and includes original research reviews and opinion pieces. The audience includes epidemiologists, medical oncologists, radiation oncologists, thoracic surgeons, pulmonologists, radiologists, pathologists, nuclear medicine physicians, and research scientists with a special interest in thoracic oncology.
Fluorinated compounds are an important group of compounds that are widely used in pharmaceuticals, agricultural chemicals, functional resins, and organic electronic materials. In particular, perfluorinated compounds with multiple carbon-fluorine bonds are attracting attention because of their high thermal and chemical stability and various excellent properties such as water and oil repellency and chemical resistance.
"C-F bonds are extremely strong; hence, their transformation under mild conditions is difficult, and the selective activation of a specific C-F bond from among multiple C-F bonds in perfluorinated compounds has not been achieved," explains Prof. Makoto Yasuda, corresponding author of the study.
The research team led by Prof. Makoto Yasuda has discovered ...
What makes cheetah the fastest land mammal? Why aren't other animals, such as horses, as fast? While we haven't yet figured out why, we have some idea about how--cheetahs, as it turns out, make use of a "galloping" gait at their fastest speeds, involving two different types of "flight": one with the forelimbs and hind limbs beneath their body following a forelimb liftoff, called "gathered flight," while another with the forelimbs and hind limbs stretched out after a hind limb liftoff, called "extended flight" (see Figure 1). Of these, the extended flight is what enables cheetahs to accelerate to high ...
Developing vaccines against bacteria is in many cases much more difficult than vaccines against viruses. Like virtually all pathogens, bacteria are able to sidestep a vaccine's effectiveness by modifying their genes. For many pathogens, such genetic adaptations under selective pressure from vaccination will cause their virulence or fitness to decrease. This lets the pathogens escape the effects of vaccination, but at the price of becoming less transmissible or causing less damage. Some pathogens, however, including many bacteria, are extremely good at changing in ways that allow them to escape the effects of vaccination while remaining highly ...
The white-tailed sea eagle is known for reacting sensitively to human disturbances. Forestry and agricultural activities are therefore restricted in the immediate vicinity of the nests. However, these seasonal protection periods are too short in the German federal States of Brandenburg (until August 31) and Mecklenburg-Western Pomerania (until July 31), as a new scientific analysis by a team of scientists from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) suggests. Using detailed movement data of 24 juvenile white-tailed sea eagles with GPS transmitters, they were able to track when they fledge and when they leave the parental territory: on average, a good 10 and ...
Materials have a variety of properties that can be used to solve computational problems, according to studies in substrate-based computing. BZ computers, slime mould computers, plant computers, and collision-based liquid marbles computers are just a few examples of prototypes produced for future and emergent computing devices. Modelling the computational processes that exist in such systems, however, is a difficult task in general, and determining which part of the embodied system is doing the computation is still somewhat ill-defined.
Claiming that fungi are the most intelligent living organisms in the world sounds like an exaggeration. However, a recent study by Mohammad Mahdi Dehshibi, a UOC researcher who is contributing to a growing body of knowledge on the use of fungal materials, ...
Eating at least two serves of fruit daily has been linked with 36 percent lower odds of developing type 2 diabetes, a new Edith Cowan University (ECU) study has found.
The study, published today in the Journal of Clinical Endocrinology and Metabolism, revealed that people who ate at least two serves of fruit per day had higher measures of insulin sensitivity than those who ate less than half a serve.
Type 2 diabetes is a growing public health concern with an estimated 451 million people worldwide living with the condition. A further 374 million people are at increased risk of developing type 2 diabetes.
The study's lead author, Dr Nicola ...
Researchers at Linköping University in Sweden have developed an app to help women achieve a healthy weight gain and lifestyle during a pregnancy. The results from an evaluation of the app have now been published in two scientific articles. Using the app contributed to a better diet. Pregnant women with overweight or obesity who received the app also gained less weight during pregnancy.
"Pregnancy is a phase in life when many people try to do what is best for themselves and their baby. We think it's important to be able to offer a tool that has ...
Good acoustics in the workspace improve work efficiency and productivity, which is one of the reasons why acoustic materials matter. The acoustic insulation market is already expected to hit 15 billion USD by 2022 as construction firms and industry pay more attention to sound environments. Researchers at Aalto University, in collaboration with Finnish acoustics company Lumir, have now studied how these common elements around us could become more eco-friendly, with the help of cellulose fibres.
'Models for acoustic absorption are based on tests done with synthetic fibres, and ...
An international research team determined that ancestors of modern domestic horses and the Przewalski horse moved from the territory of Eurasia (Russian Urals, Siberia, Chukotka, and eastern China) to North America (Yukon, Alaska, continental USA) from one continent on another at least twice. It happened during the Late Pleistocene (2.5 million years ago - 11.7 thousand years ago). The analysis results are published in the journal. The findings and description of horse genomes are published in the journal Molecular Ecology.
"We found out that the Beringian Land Bridge, or the area known as Beringia, influenced genetic ...
All the cells of an organism share the same DNA sequence, but their functions, shapes or even lifespans vary greatly. This happens because each cell "reads" different chapters of the genome, thus producing alternative sets of proteins and embarking on different paths. Epigenetic regulation--DNA methylation is one of the most common mechanisms--is responsible for the activation or inactivation of a given gene in a specific cell, defining a secondary cell-specific genetic code.
Researchers led by Dr. Modesto Orozco, head of the Molecular Modelling and Bioinformatics lab at IRB Barcelona, have described how methylation has a protein-independent regulatory role by increasing the stiffness of DNA, which affects the 3D structure ...
