Exploring the Impact of the Obesity Paradox on Lung Cancer and Other Malignancies

Sex differences in the obesity paradox of body compositions in non-small cell lung cancer

OBJECTIVES

This study investigated the correlation between body mass index (BMI), bioelectrical impedance analysis (BIA)-derived specific body compositions, and the obesity paradox, with a focus on sex differences in non-smallcell lung cancer (NSCLC).

METHODS

This study is a multicenter prospective cohort. Association with survival was determined using Cox proportional hazard regression analysis. The mediating effect of systemic inflammation on the association between body composition and survival rate was determined using mediation analysis.

RESULTS

Fat mass had a strong positive correlation with BMI, but a weak positive correlation with other BIA-derived body compositions. Obese, overweight, and normal weight patients had significantly longer median survival than patients with BMI <18.5 ([23.2 versus 18.5 versus 17.5 versus 15.8] months, P < 0.001). Increased BMI and BIA-derived body composition indicators were associated with decreased all-cause mortality. Multivariable-adjusted analysis demonstrated that BMI, fat mass (FM), fat-free mass, muscle mass, bone mass, protein mass, total body water, extracellular water, and intracellular water were independent protective factors affecting the prognosis of patients with NSCLC. A difference in body compositions performance in the prognostic assessment of the different sexes was observed. Fat-related body compositions exhibited a significant obesity paradox in females compared to in males. Systemic inflammation played a crucial role in the relationship between body compositions and disease prognosis, with a mediating effect on body fat in males (31%) and females (19.7%).

CONCLUSIONS

The obesity paradox exists among patients with NSCLC and is not influenced by specific body compositions. In addition, this paradox is notably more common in female patients.

TRIAL REGISTRATION

Registration number: ChiCTR1800020329.

Lifestyle, Environmental, Occupational, and Dietary Risk Factors in Small-Cell vs. Non-Small-Cell Advanced Lung Cancer Patients: Is There a Connection?

OBJECTIVES

(i) To evaluate the possible exposure of newly diagnosed lung cancer patients to selected lifestyle, environmental, occupational, and dietary risk factors and (ii) to assess the differences in exposures of small-cell (SCLC) and non-small-cell (NSCLC) lung cancer patients to those risk factors.

METHODS

In this study, 205 newly diagnosed patients with IIIB/IV stage of either SCLC or NSCLC (111 men vs. 94 women) from Vojvodina, Serbia, were surveyed for selected demographic characteristics, dietary and lifestyle habits, and environmental factors.

RESULTS

Most patients were long-term heavy smokers. The body mass index values of SCLC patients were higher than those of NSCLC patients. Women reported higher stress levels compared to men. Women diagnosed with lung adenocarcinoma were more often exposed to traffic pollution compared to men. Individual indoor coal combustion systems were more often used by SCLC patients of both sexes compared to other cancer types. Men were more frequent consumers of canned foods, which are potential sources of endocrine disruptors. Occupational exposure to lung cancer risk factors, in addition to tobacco smoking, may be crucial in lung cancer development with specific occupations.

CONCLUSIONS

Further research on environmental and occupational risk factors for lung cancer is urgent in order to unveil the etiopathogenesis of specific lung cancer types.

Psoas muscle index as a novel measure of frailty and predictor of post-operative outcome in octogenarians with non-small cell lung cancer

Background

High body mass index (BMI) is a prevalent risk factor in a growing octogenarian population undergoing curative surgery for non-small cell lung cancer (NSCLC). Whilst BMI is paradoxically protective, its correlation with clinical frailty or objective fitness is unclear, due to the discrepancy of the ratio between muscle and adipose tissue. We aim to assess the relationship between sarcopenia and post operative survival and complications.

Methods

Demographic and clinical outcome data from octogenarians undergoing resections for primary NSCLC (January 2016-December 2021) was analysed retrospectively. Routine pre-operative positron emission tomography-computed tomography (PET-CT) scan was used to derive psoas muscle index (PMI) (bilateral measurement of cross-sectional psoas muscle area at the level of L3, divided by height-squared) as a measure of sarcopenia.

Results

A total of 189 patients were recruited with a mean age 82 years. Median overall survival (OS) was 2.7 vs. 3.0 years in males and females, respectively (P<0.001). Chronic obstructive pulmonary disease (COPD) (P=0.02) and pathological stage >Ia (P=0.02) reduced OS. In males, OS at 5 years increased with PMI (58.3% for ≥9.0 vs. 0% at <4.9 cm2/m2) (P=0.04) and BMI (38.3% at 30-39.9 kg/m2 vs. 0% at <18.5 kg/m2) (P<0.001). In females, 5-year OS increased with BMI (100% at >30 kg/m2) (P=0.05) but not with PMI. Median disease-free survival (DFS) was 2.8 vs. 2.7 years in males and females, respectively (P<0.001). The 5-year DFS was not affected by PMI or BMI in males nor females; 11.1% of patients had major postoperative complications, predicted by squamous cell carcinoma (P=0.03) and stage >Ia (P<0.01). Lower BMI ranges had proportionally more major complications in males (P<0.001), however the opposite was true for females. Mean hospital stay was 4 days longer in males, and doubled with higher BMI [12 days (range, 8-12 days); P=0.76]. BMI and PMI correlated positively in both males (r=0.36, P<0.001), and females (r=0.32, P=0.002).

Conclusions

Radiologically derived PMI is an easily replicable marker which may be a useful adjunct to BMI in identifying high-risk octogenarians in whom prehabilitation may achieve superior outcomes post-surgery for NSCLC. Additionally, the method we describe avoids additional imaging to derive these measurements and can be safely incorporated into pre-operative imaging protocols.

Weight loss as a predictor of reduced survival in patients with lung cancer: a systematic review with meta-analysis

BACKGROUND

The impact of weight loss on survival outcomes remains challenging in patients with lung cancer. The objective of this systematic review with meta-analysis was to assess the association of weight loss with survival outcomes in these patients.

METHODS

Two authors conducted a comprehensive literature search of PubMed, Web of Science, and Embase databases up to January 15, 2024. Observational studies that assessed the weight loss as a prognostic factor of overall survival and progression-free survival in patients with lung cancer were included this analysis. Weight loss defined by at least 5% loss of total body weight over 2 months.

RESULTS

Fifteen studies involving 14,540 patients with lung cancer were included. Pooled adjusted hazard ratios (HR) indicated that weight loss was associated with reduced overall survival (HR 1.65; 95% confidence intervals [CI] 1.43-1.91) and progression-free survival (HR 1.40; 95% CI 1.15-1.71). Subgroup analysis showed that weight loss significantly predicted overall survival, regardless of study design, lung cancer subtypes, clinical stage of cancer, weight loss definition, or length of follow-up.

CONCLUSIONS

Weight loss is a significant predictor of overall survival and progression-free survival in patients with lung cancer. Weight monitoring has potential to improve prognostication of survival outcomes for these patients.

Adherence to higher Life's Essential 8 scores is linearly associated with reduced all-cause and cardiovascular mortality among US adults with metabolic syndrome: Results from NHANES 2005-2018

BACKGROUND

Life's Essential 8 (LE8) is the American Heart Association (AHA)'s recently updated assessment of cardiovascular health (CVH). Metabolic syndrome (MetS) is one of the most common chronic noncommunicable diseases associated with CVH impairment and an increased risk of mortality. However, the association of LE8 with all-cause and disease-specific mortality in the MetS population remains unknown. We aimed to explore these associations in a national prospective cohort study from NHANES 2005-2018.

METHODS

The LE8 was calculated according to the assessment criteria proposed by the AHA, which includes health behavior and health factor domains. LE8 scores were categorized as low CVH (0-49), moderate CVH (50-79), and high CVH (80-100). MetS was assessed according to NCEP-ATP III criteria, and mortality data were obtained through prospective linkage to the National Death Index database.

RESULTS

7839 participants with MetS were included and only 3.5% were in high CVH. In the fully adjusted models, LE8 was negatively associated with both all-cause and cardiovascular disease (CVD) mortality (hazard ratios [HR] and 95% confidence intervals [CI] of 0.978 (0.971,0.984) and 0.972 (0.961,0.984), respectively, both p < 0.0001). Both moderate/high CVH were associated with significantly lower mortality compared to low CVH (both p for trend <0.0001). Health behaviors had a more dominant effect compared to health factors. All-cause and CVD mortality gradually decreased with increasing ideal LE8 metrics. LE8 was not significantly associated with cancer mortality. LE8 and health behaviors were linearly associated with all-cause and CVD mortality, whereas health factors were nonlinearly associated (plateaued after ≥50). Education and chronic kidney disease influenced the association of LE8 with all-cause and CVD mortality, respectively.

CONCLUSIONS

LE8 scores were negatively associated with all-cause and CVD mortality in the MetS population, while health behaviors had a dominant role. Adherence to higher CVH contributes to the prevention of excessive all-cause and CVD mortality in the MetS population.

Vascular Biomarkers for Pulmonary Nodule Malignancy: Arteries vs. Veins

OBJECTIVE

This study aims to investigate the association between the arteries and veins surrounding a pulmonary nodule and its malignancy.

METHODS

A dataset of 146 subjects from a LDCT lung cancer screening program was used in this study. AI algorithms were used to automatically segment and quantify nodules and their surrounding macro-vasculature. The macro-vasculature was differentiated into arteries and veins. Vessel branch count, volume, and tortuosity were quantified for arteries and veins at different distances from the nodule surface. Univariate and multivariate logistic regression (LR) analyses were performed, with a special emphasis on the nodules with diameters ranging from 8 to 20 mm. ROC-AUC was used to assess the performance based on the k-fold cross-validation method. Average feature importance was evaluated in several machine learning models.

RESULTS

The LR models using macro-vasculature features achieved an AUC of 0.78 (95% CI: 0.71-0.86) for all nodules and an AUC of 0.67 (95% CI: 0.54-0.80) for nodules between 8-20 mm. Models including macro-vasculature features, demographics, and CT-derived nodule features yielded an AUC of 0.91 (95% CI: 0.87-0.96) for all nodules and an AUC of 0.82 (95% CI: 0.71-0.92) for nodules between 8-20 mm. In terms of feature importance, arteries within 5.0 mm from the nodule surface were the highest-ranked among macro-vasculature features and retained their significance even with the inclusion of demographics and CT-derived nodule features.

CONCLUSIONS

Arteries within 5.0 mm from the nodule surface emerged as a potential biomarker for effectively discriminating between malignant and benign nodules.

Sarcopenic obesity predicts short- and long-term outcomes after neoadjuvant chemotherapy and surgery for gastric cancer

BACKGROUND

Sarcopenic obesity (SO) affects outcomes in various malignancies. However, its clinical significance in patients undergoing neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer (LAGC) remains unclear. This study investigated the impact of pre- and post-NAC SO on postoperative morbidity and survival.

METHODS

Data from 207 patients with LAGC, who underwent NAC followed by radical gastrectomy between January 2010 and October 2019, were reviewed. Skeletal muscle mass and visceral fat area were measured pre- and post-NAC using computed tomography to define sarcopenia and obesity, the coexistence of which was defined as SO.

RESULTS

Among the patients, 52 (25.1%) and 38 (18.4%) developed SO before and after NAC, respectively. Both pre- (34.6%) and post- (47.4%) NAC SO were associated with the highest postoperative morbidity rates; however, only post-NAC SO was an independent risk factor for postoperative morbidity [hazard ratio (HR) = 9.550, 95% confidence interval (CI) = 2.818-32.369; P < .001]. Pre-NAC SO was independently associated with poorer 3-year overall [46.2% vs. 61.3%; HR = 1.258 (95% CI = 1.023-1.547); P = .049] and recurrence-free [39.3% vs. 55.4%; HR 1.285 (95% CI 1.045-1.579); P = .017] survival.

CONCLUSIONS

Pre-NAC SO was an independent prognostic factor in patients with LAGC undergoing NAC; post-NAC SO independently predicted postoperative morbidity.

Association between non-alcoholic fatty liver disease and the risk of pulmonary nodules in patients with intestinal polyps

Background

Associations between metabolic risk factors and lung cancer remain elusive, and evidence on the linkage between non-alcoholic fatty liver disease (NAFLD) and pulmonary nodules is limited. This study sought to examine the independent association between NAFLD and the risk of pulmonary nodules.

Methods

Cross-sectional analyses of 1,119 patients with intestinal polyps hospitalized at the Department of Gastroenterology, Minhang District Central Hospital of Shanghai, China, were conducted. NAFLD was diagnosed based on hepatic ultrasonography or computed tomography (CT) findings of hepatic steatosis, with exclusion criteria ensuring patients had no history of significant alcohol consumption, viral infections, or hepatic autoimmune diseases. The currently accepted definition of a pulmonary nodule is a solid or sub-solid shadow ≤3 cm in diameter that appears as a solid or semi-solid pattern on a chest CT scan (our specific treatment is pulmonary nodule size: 5 mm to 3 cm). Adjusted 95% confidence intervals (CIs) and odds ratios (ORs) for NAFLD and the clinical features connected with pulmonary nodule risk were determined using a multivariable logistic regression analysis.

Results

Among the 979 intestinal polyp patients, the prevalence rates of NAFLD and pulmonary nodules were 25.9% and 32.8%, respectively. Patients with pulmonary nodules exhibited higher rates of NAFLD (31.5% vs. 23.3%, P=0.006) and obesity (41.4% vs. 32.5%, P=0.006) compared to those without pulmonary nodules. After removing all the possible confounding variables, the adjusted ORs for NAFLD, an older age, smoking, and obesity were 1.370 (95% CI: 1.006-1.867, P=0.04), 1.022 (95% CI: 1.010-1.033), 1.599 (95% CI: 1.033-2.475), and 1.410 (95% CI: 1.057-1.880), respectively (all P values <0.05). NAFLD showed a significant association with an increased risk of pulmonary nodules.

Conclusions

NAFLD was independently linked to an increased incidence of pulmonary nodules in intestinal polyp patients, which emphasizes the importance of screening and managing these conditions in lung cancer prevention.

Influence of Biomarkers on Mortality among Patients with Hepatic Metastasis of Colorectal Cancer Treated with FOLFOX/CAPOX and FOLFIRI/CAPIRI, Including Anti-EGFR and Anti-VEGF Therapies

Background and objectives: Colorectal cancer is a major global health concern, with a significant increase in morbidity and mortality rates associated with metastatic stages. This study investigates the prognostic significance of various clinical and laboratory parameters in patients with metastatic CRC. Materials and Methods: A retrospective cohort of 188 CRC patients with hepatic metastasis from the OncoHelp Association in Timisoara was analyzed from January 2016 to March 2023. Data on demographics, clinical characteristics, and biomarkers, such as lymphocyte counts, as well as various inflammation indices, were examined. Statistical analyses included univariate and multivariate logistic regression, Kaplan-Meier survival analysis, and ROC curve assessments. Results: Our findings indicate significant associations between survival outcomes and several biomarkers. Higher BMI and lymphocyte counts were linked with better survival rates, while higher values of Neutrophil-Hemoglobin-Lymphocyte (NHL) score, Neutrophil-Lymphocyte Ratio (NLR), Platelet-Lymphocyte Ratio (PLR), and Systemic Immune-Inflammation Index (SII) were predictors of poorer outcomes. Notably, the presence of hepatic metastasis at diagnosis was a critical factor, significantly reducing overall survival. Conclusions: The study has expanded the current understanding of prognostic factors in CRC, advocating for a multi-dimensional approach to prognostic evaluations. This approach should consider not only the traditional metrics such as tumor stage and histological grading but also incorporate a broader spectrum of biomarkers. Future studies should aim to validate these findings and explore the integration of these biomarkers into routine clinical practice, enhancing the precision of prognostic assessments and ultimately guiding more personalized treatment strategies for CRC patients.

Neoadjuvant therapy in non-small cell lung cancer: basis, promise, and challenges

Introduction

Survival rates for early-stage non-small cell lung cancer (NSCLC) remain poor despite the decade-long established standard of surgical resection and systemic adjuvant therapy. Realizing this, researchers are exploring novel therapeutic targets and deploying neoadjuvant therapies to predict and improve clinical and pathological outcomes in lung cancer patients. Neoadjuvant therapy is also increasingly being used to downstage disease to allow for resection with a curative intent. In this review, we aim to summarize the current and developing landscape of using neoadjuvant therapy in the management of NSCLC.

Methods

The PubMed.gov and the ClinicalTrials.gov databases were searched on 15 January 2023, to identify published research studies and trials relevant to this review. One hundred and seven published articles and seventeen ongoing clinical trials were selected, and relevant findings and information was reviewed.

Results & Discussion

Neoadjuvant therapy, proven through clinical trials and meta-analyses, exhibits safety and efficacy comparable to or sometimes surpassing adjuvant therapy. By attacking micro-metastases early and reducing tumor burden, it allows for effective downstaging of disease, allowing for curative surgical resection attempts. Research into neoadjuvant therapy has necessitated the development of surrogate endpoints such as major pathologic response (MPR) and pathologic complete response (pCR) allowing for shorter duration clinical trials. Novel chemotherapy, immunotherapy, and targeted therapy agents are being tested at a furious rate, paving the way for a future of personalized systemic therapy in NSCLC. However, challenges remain that prevent further mainstream adoption of preoperative (Neoadjuvant) therapy. These include the risk of delaying curative surgical resection in scenarios of adverse events or treatment resistance. Also, the predictive value of surrogate markers of disease cure still needs robust verification. Finally, the body of published data is still limited compared to adjuvant therapy. Addressing these concerns with more large scale randomized controlled trials is needed.

Seven preoperative factors have strong predictive value for postoperative pneumonia in patients undergoing thoracoscopic lung cancer surgery

Background

Postoperative pneumonia (POP) is a hospital acquired pneumonia that occurs >48 hours after tracheal intubation. The diagnosis of POP should be based on clinical and radiological findings within 30 days after surgery. It is a common complication after thoracoscopic surgery for lung cancer patients. However, the specific impact of preoperative comorbidities on the incidence of POP remains unclear. This study aimed to analyze the preoperative data of patients with lung cancer to help surgeons predict the risk of incidence of POP after thoracoscopic lung resection.

Methods

This study is a prospective study that included patients with lung cancer who were scheduled for thoracoscopic surgery in 1 year. All cases came from two medical centers. Preoperative demographic information, tumor information, preoperative comorbidities, quality of life scores, and incidence of POP were collected. Variables were screened by univariate analysis and multivariate regression. Finally, a prediction model was constructed. A total of 53 preoperative factors were included as candidate predictors. The binary outcome variable was defined as the presence or absence of POP. The incidence of POP was the primary outcome variable. The predictive performance of the model was verified internally through 1,000 iterations of bootstrap resampling.

Results

A total of 1,229 patients with lung cancer who underwent thoracoscopic surgery were enrolled. In addition, 196 cases (15.95%) had POP; 1,025 (83.40%) patients had comorbid conditions. The total number of comorbidity diagnosed in all samples was 2,929. The prediction model suggested that patients with advanced age, high body mass index (BMI), smoking, poor physical condition, respiratory diseases, diabetes, and neurological diseases were more likely to develop POP. The area under the curve (AUC) and Brier scores were 0.851 and 0.091, respectively. The expected and observed results were in strong agreement, according to the likelihood of POP calibration curve.

Conclusions

The constructed model is capable of evaluating the probability of POP occurrence in patients with lung cancer. Seven preoperative factors in patients with lung cancer were found to be associated with increased probability of having pneumonia after thoracoscopic lung resection. This model can help predict the incidence of POP after surgery.

Obesity Paradox in Lung Diseases: What Explains It?

BACKGROUND

Obesity is a globally increasing health problem that impacts multiple organ systems and a potentially modifiable risk factor for many diseases. Obesity has a significant impact on lung function and is strongly linked to the pathophysiology that contributes to lung diseases. On the other hand, reports have emerged that obesity is associated with a better prognosis than for normal weight individuals in some lung diseases, including pneumonia, acute lung injury/acute respiratory distress syndrome, chronic obstructive pulmonary disease, and lung cancer. The lesser mortality and better prognosis in patients with obesity is known as obesity paradox. While obesity paradox is both recognized and disputed in epidemiological studies, recent research has suggested possible mechanisms.

SUMMARY

In this review, we attempted to explain and summarize these factors and mechanisms, including immune response, pulmonary fibrosis, lung function, microbiota, fat and muscle reserves, which are significantly altered by obesity and may contribute to the obesity paradox in lung diseases. We also discuss contrary literature that attributes the "obesity paradox" to confounding.

KEY MESSAGES

The review will illustrate the possible role of obesity in the prognosis or course of lung diseases, leading to a better understanding of the obesity paradox and provide hints for further basic and clinical research in lung diseases.

Obesity and the risk of cardiometabolic diseases

The prevalence of obesity has reached pandemic proportions, and now approximately 25% of adults in Westernized countries have obesity. Recognized as a major health concern, obesity is associated with multiple comorbidities, particularly cardiometabolic disorders. In this Review, we present obesity as an evolutionarily novel condition, summarize the epidemiological evidence on its detrimental cardiometabolic consequences and discuss the major mechanisms involved in the association between obesity and the risk of cardiometabolic diseases. We also examine the role of potential moderators of this association, with evidence for and against the so-called 'metabolically healthy obesity phenotype', the 'fatness but fitness' paradox or the 'obesity paradox'. Although maintenance of optimal cardiometabolic status should be a primary goal in individuals with obesity, losing body weight and, particularly, excess visceral adiposity seems to be necessary to minimize the risk of cardiometabolic diseases.

The effect of perioperative immunonutritional support on nutritional and inflammatory status in patients undergoing lung cancer surgery: a prospective, randomized controlled study

PURPOSE

Nutritional status is affected in patients who undergo lung cancer surgery (LCS). This study is aimed at investigating the effects of the use of immunonutritional support in the perioperative period on nutritional and inflammatory status in patients undergoing LCS.

METHODS

A single-center, prospective, randomized controlled clinical trial was conducted with seventy patients planning to have LCS and randomized into treatment (TG) and control groups (CG). Immunonutritional support was given orally twice a day for ten days before the operation and five days after the operation in the treatment group. The nutritional status of the patients was screened with the Patient-Generated Subjective Global Assessment (PG-SGA); the Prognostic Nutrition Index (PNI) and the Systemic Inflammation Index (SII) were calculated. The physical activity status was assessed with the Eastern Cooperative Oncology Group Performance Status (ECOG-PS).

RESULTS

Post-op nutritional status of the TG patients was better than the CG group (p = 0.009). Post-operative PG-SGA score was higher than preoperative PG-SGA score in both groups (p < 0.001). In the post-operative period, nutritional status (in terms of PG-SGA score category) in the patients in the TG was better than the CG (p = 0.046). In both groups, post-op ECOG score was higher than the pre-op ECOG score (p < 0.001). Post-op physical performance status was found to be better in the TG compared to the CG (p = 0.001). PNI level decreased statistically and significantly in the post-op period compared to the pre-op period, SII levels increased.

CONCLUSION

Patients who will undergo LCS should be supported in terms of immunonutrition starting from the preoperative period.

Predictive scoring of high-grade histology among early-stage lung cancer patients: The MOSS score

BACKGROUND

Poor prognosis associated with adenocarcinoma of International Association for the Study of Lung Cancer (IASLC) grade 3 has been recognized. In this study we aimed to develop a scoring system for predicting IASLC grade 3 based before surgery.

METHODS

Two retrospective datasets with significant heterogeneity were used to develop and evaluate a scoring system. The development set was comprised of patients with pathological stage I nonmucinous adenocarcinoma and they were randomly divided into training (n = 375) and validation (n = 125) datasets. Using multivariate logistic regression, a scoring system was developed and internally validated. Later, this new score was further tested in the testing set which was comprised of patients with clinical stage 0-I non-small cell lung cancer (NSCLC) (n = 281).

RESULTS

Four factors that were related to IASLC grade 3 were used to develop the new scoring system the MOSS score; male (M, point 1), overweight (O, point 1), size>10 mm (S, point 1), and solid lesions (S, point 3). Predictability of IASLC grade 3 increased from 0.4% to 75.2% with scores from 0 to 6. The area under the curve (AUC) of the MOSS was 0.889 and 0.765 for the training and validation datasets, respectively. The MOSS score exhibited similar predictability in the testing set (AUC: 0.820).

CONCLUSION

The MOSS score, which combines preoperative variables, can be used to identify high-risk early-stage NSCLC patients with aggressive histological features. It can support clinicians in determining a treatment plan and surgical extent. Further refinement of this scoring system with prospective validation is needed.

Obesity, the Adipose Organ and Cancer in Humans: Association or Causation?

Epidemiological observations, experimental studies and clinical data show that obesity is associated with a higher risk of developing different types of cancer; however, proof of a cause-effect relationship that meets the causality criteria is still lacking. Several data suggest that the adipose organ could be the protagonist in this crosstalk. In particular, the adipose tissue (AT) alterations occurring in obesity parallel some tumour behaviours, such as their theoretically unlimited expandability, infiltration capacity, angiogenesis regulation, local and systemic inflammation and changes to the immunometabolism and secretome. Moreover, AT and cancer share similar morpho-functional units which regulate tissue expansion: the adiponiche and tumour-niche, respectively. Through direct and indirect interactions involving different cellular types and molecular mechanisms, the obesity-altered adiponiche contributes to cancer development, progression, metastasis and chemoresistance. Moreover, modifications to the gut microbiome and circadian rhythm disruption also play important roles. Clinical studies clearly demonstrate that weight loss is associated with a decreased risk of developing obesity-related cancers, matching the reverse-causality criteria and providing a causality correlation between the two variables. Here, we provide an overview of the methodological, epidemiological and pathophysiological aspects, with a special focus on clinical implications for cancer risk and prognosis and potential therapeutic interventions.

Inappropriate dietary habits in tobacco smokers as a potential risk factor for lung cancer: Pomeranian cohort study

OBJECTIVE

Little is known whether diet quality modulates lung cancer risk in smokers. The aim of the study was to assess the dietary habits of a large group of volunteers participating in the lung cancer screening program.

METHODS

The 62-item food frequency questionaire was completed by 5997 participants, 127 of whom (2.1%) were later diagnosed with lung cancer. Two approaches were applied to identify dietary habits. The non-healthy diet index was calculated, and a direct analysis of the frequency of consumption was used. A logistic regression analysis was performed to estimate the association between food product intake and the risk of lung cancer.

RESULTS

The study population did not follow the Polish nutritional recommendations. They consumed fruits and vegetables too rarely and far too often ate non-recommended foods, such as processed meat, refined products, sugar, sweets, and salty snacks. Participants diagnosed with lung cancer more often consumed low-quality processed meat, red meat, fats, and refined bread and less often whole-grain products, tropical fruits, milk, fermented unsweetened milk drinks, nuts, honey, and wine. The non-healthy diet index score was significantly higher in those with cancer diagnosis compared with those without lung cancer (11.9 ± 5.2 versus 10.9 ± 5.3; P < 0.001).

CONCLUSIONS

The surveyed population of smokers did not follow dietary recommendations; there was a particularly high index of an unhealthy diet in by people diagnosed with lung cancer. Prevention programs should be based on encouraging smoking cessation, lifestyle modification, and methods of early detection of lung cancer. Lifestyle modification should include changing eating habits based on a healthy diet, which may be an additional factor in reducing the risk of developing cancer.

Muscle distribution in relation to all-cause and cause-specific mortality in young and middle-aged adults

BACKGROUND

The relationship between muscle and prognosis, especially that between muscle distribution across different body parts, and the related prognosis is not well established.

OBJECTIVE

To investigate the relationship between muscle distribution and all-cause and cause-specific mortality and their potential modifiers.

DESIGN

Longitudinal cohort study. C-index, IDI, and NRI were used to determine the best indicator of prognosis. COX regression analysis was performed to explore the relationship between variables and outcomes. Interaction and subgroup analyses were applied to identify the potential modifiers.

PARTICIPANTS

A total of 5052 participants (weighted: 124,841,420) extracted from the NHANES 2003-2006 of median age 45 years and constituting 50.3% men were assessed. For validation, we included 3040 patients from the INSCOC cohort in China.

MAIN MEASURES

Muscle mass and distribution. KEY RESULTS: COX regression analysis revealed that upper limbs (HR = 0.41, 95% CI 0.33-0.51), lower limbs (HR = 0.54, 95% CI 0.47-0.64), trunk (HR = 0.71, 95% CI, 0.59-0.85), gynoid (HR = 0.47, 95% CI 0.38-0.58), and total lean mass (HR = 0.55, 95% CI 0.45-0.66) were all associated with the better survival of participants (P trend < 0.001). The changes in the lean mass ratio of the upper and lower limbs and the lean mass ratio of the android and gynoid attenuated the protective effect of lean mass. Age and sex acted as potential modifiers, and the relationship between lean mass and the prognosis was more significant in men and middle-aged participants when compared to that in other age groups. Sensitive analyses depicted that despite lean mass having a long-term impact on prognosis (15 years), it has a more substantial effect on near-term survival (5 years).

CONCLUSION

Muscle mass and its distribution affect the prognosis with a more significant impact on the near-term than that on the long-term prognosis. Age and sex acted as vital modifiers.

Abdominal Fat Characteristics and Mortality in Rectal Cancer: A Retrospective Study

The aim of this study was to evaluate the association of adipose tissue characteristics with survival in rectal cancer patients. All consecutive patients, diagnosed with stage II-IV rectal cancer between 2010-2016 using baseline unenhanced Computed Tomography (CT), were included. Baseline total, subcutaneous and visceral adipose tissue areas (TAT, SAT, VAT) and densities (TATd, SATd, VATd) at third lumbar vertebra (L3) were retrospectively measured. The association of these tissues with cancer-specific and progression-free survival (CCS, PFS) was assessed by using competitive risk models adjusted by age, sex and stage. Among the 274 included patients (median age 70 years, 41.2% females), the protective effect of increasing adipose tissue area on survival could be due to random fluctuations (e.g., sub-distribution hazard ratio-SHR for one cm² increase in SAT = 0.997; 95%confidence interval-CI = 0.994-1.000; p = 0.057, for CSS), while increasing density was associated with poorer survival (e.g., SHR for one Hounsfield Unit-HU increase in SATd = 1.03, 95% CI = 1.01-1.05, p = 0.002, for CSS). In models considering each adipose tissue area and respective density, the association with CSS tended to disappear for areas, while it did not change for TATd and SATd. No association was found with PFS. In conclusion, adipose tissue density influenced survival in rectal cancer patients, raising awareness on a routinely measurable variable that requires more research efforts.

Visceral Obesity in Non-Small Cell Lung Cancer

While obesity measured by body mass index (BMI) has been paradoxically associated with reduced risk and better outcome for lung cancer, recent studies suggest that the harm of obesity becomes apparent when measured as visceral adiposity. However, the prevalence of visceral obesity and its associations with demographic and tumor features are not established. We therefore conducted an observational study of visceral obesity in 994 non-small cell lung cancer (NSCLC) patients treated during 2008-2020 at our institution. Routine computerized tomography (CT) images of the patients, obtained within a year of tumor resection or biopsy, were used to measure cross-sectional abdominal fat areas. Important aspects of the measurement approach such as inter-observer variability and time stability were examined. Visceral obesity was semi-quantified as visceral fat index (VFI), the fraction of fat area that was visceral. VFI was found to be higher in males compared to females, and in former compared to current or never smokers. There was no association of VFI with tumor histology or stage. A gene expression-based measure of tumor immunogenicity was negatively associated with VFI but had no bearing with BMI. Visceral obesity is appraisable in routine CT and can be an important correlate in lung cancer studies.