Bevacizumab for metastatic colon cancer: does patient BMI influence survival?

Post-diagnosis adiposity and colorectal cancer prognosis: A Global Cancer Update Programme (CUP Global) systematic literature review and meta-analysis

The adiposity influence on colorectal cancer prognosis remains poorly characterised. We performed a systematic review and meta-analysis on post-diagnosis adiposity measures (body mass index [BMI], waist circumference, waist-to-hip ratio, weight) or their changes and colorectal cancer outcomes. PubMed and Embase were searched through 28 February 2022. Random-effects meta-analyses were conducted when at least three studies had sufficient information. The quality of evidence was interpreted and graded by the Global Cancer Update Programme (CUP Global) independent Expert Committee on Cancer Survivorship and Expert Panel. We reviewed 124 observational studies (85 publications). Meta-analyses were possible for BMI and all-cause mortality, colorectal cancer-specific mortality, and cancer recurrence/disease-free survival. Non-linear meta-analysis indicated a reverse J-shaped association between BMI and colorectal cancer outcomes (nadir at BMI 28 kg/m2). The highest risk, relative to the nadir, was observed at both ends of the BMI distribution (18 and 38 kg/m2), namely 60% and 23% higher risk for all-cause mortality; 95% and 26% for colorectal cancer-specific mortality; and 37% and 24% for cancer recurrence/disease-free survival, respectively. The higher risk with low BMI was attenuated in secondary analyses of RCTs (compared to cohort studies), among studies with longer follow-up, and in women suggesting potential methodological limitations and/or altered physiological state. Descriptively synthesised studies on other adiposity-outcome associations of interest were limited in number and methodological quality. All the associations were graded as limited (likelihood of causality: no conclusion) due to potential methodological limitations (reverse causation, confounding, selection bias). Additional well-designed observational studies and interventional trials are needed to provide further clarification.

Effect of body mass index on survival in patients with metastatic colorectal cancer receiving chemotherapy plus bevacizumab: a systematic review and meta-analysis

Aim

This systematic review and meta-analysis was to evaluate the relationship between body mass index (BMI) and the clinical outcomes in patients with metastatic colorectal cancer (mCRC) undergoing treatment with bevacizumab plus chemotherapy.

Methods

The search for relevant literature was conducted across PubMed, Embase, Cochrane Library, and Web of Science, with the final search date being October 4, 2023. We utilized the weighted mean differences (WMDs), risk ratios (RRs), or Hazard ratios (HRs) as the metric for effect sizes, which were accompanied by 95% confidence intervals (CIs).

Results

A total of 9 studies were included for analysis. The results indicated that non-obese patients with mCRC undergoing treatment with bevacizumab experienced a reduced overall survival (OS) at the six-month compared to their obese counterparts (RR: 0.97, 95% CI: 0.94 to 1.00, p = 0.047). Furthermore, no significant differences in one-year, two-year, and five-year OS, as well as PFS and median OS, were observed between obese and non-obese mCRC patients undergoing treatment with bevacizumab plus chemotherapy.

Conclusion

These findings suggest that obesity may play a role in the short-term OS of patients with mCRC undergoing bevacizumab treatment. The clinical implications of these findings underscore the importance of considering patients' BMI in the context of mCRC care. This study may also help guide personalized treatment strategies and further research into the interplay between obesity, treatment efficacy, and patient survival in mCRC. However, further investigation is warranted to substantiate the findings of this study.

Expected and paradoxical effects of obesity on cancer treatment response

Obesity, whose prevalence is pandemic and continuing to increase, is a major preventable and modifiable risk factor for diabetes and cardiovascular diseases, as well as for cancer. Furthermore, epidemiological studies have shown that obesity is a negative independent prognostic factor for several oncological outcomes, including overall and cancer-specific survival, for several site-specific cancers as well as for all cancers combined. Yet, a recently growing body of evidence suggests that sometimes overweight and obesity may associate with better outcomes, and that immunotherapy may show improved response among obese patients compared with patients with a normal weight. The so-called 'obesity paradox' has been reported in several advanced cancer as well as in other diseases, albeit the mechanisms behind this unexpected relationship are still not clear. Aim of this review is to explore the expected as well as the paradoxical relationship between obesity and cancer prognosis, with a particular emphasis on the effects of cancer therapies in obese people.

Clinical Factors Affecting Bevacizumab Efficacy With and Without Conventional Chemotherapy in Metastatic Colon Cancer

PURPOSE

Bevacizumab (BZ) combined with first line chemotherapy (CC) has shown good clinical outcomes in metastatic colorectal cancer (mCRC). Overall survival (OS) and/or progression free survival in mCRC patients receiving BZ with or without 5FU-based CC is thought to be affected by clinical and morphological factor(s).

PATIENTS AND METHODS

We reviewed retrospective medical records of all consecutive mCRC patients treated with BZ with or without CC at tertiary care center between 2003 and 2009 out of which149 patients (m = 77, f = 72) were eligible.

RESULTS

Our study population had a mean age at diagnosis of 63.5 years (SD = 11) with median follow-up period of 19.4 months. On initial radiological evaluation following BZ therapy, 56 patients (m = 31, f = 25) had complete or partial response categorized as "early responders." Remaining patients (m = 46, f = 47) who were either stable or showed progressive disease were categorized as "non-responders." Fifty percent among early responders and 60% among non-responders [relative risk (RR) 0.67 (95% confidence interval (CI), 0.43-1.06)] demonstrated disease progression on follow up. There was a slightly better OS among early responders compared to non-responders (median 21.5 months days versus 16.8 months, P = 0.07). Cox regression analysis suggested male sex (RR 0.65, 95% CI, 0.43-0.98), hematochezia (RR 0.63, 95% CI, 0.4-0.98), resectable primary tumor (RR 0.42, 95% CI, 0.24-0.72) and resectable metastatic mass (RR 0.32, 95% CI, 0.14-0.74) were found to be associated with longer OS. Abdominal pain (RR 1.76, 95% CI, 1.1-2.8), accompanying diabetes (RR 1.76, 95% CI, 1.09-2.85), and unexplained weight loss (RR 2.73, 95% CI, 1.73-4.29) were associated with poor OS.

CONCLUSIONS

Better OS among mCRC patients with resectable primary and metastatic tumors was seen. This is the first study to demonstrate slightly better outcome in males and negative influence of diabetes on outcome in mCRC treated with BZ.

Association of Obesity With Survival Outcomes in Patients With Cancer: A Systematic Review and Meta-analysis

Importance

Obesity, defined as a body mass index (BMI) greater than 30, is associated with a significant increase in the risk of many cancers and in overall mortality. However, various studies have suggested that patients with cancer and no obesity (ie, BMI 20-25) have worse outcomes than patients with obesity.

Objective

To assess the association between obesity and outcomes after a diagnosis of cancer.

Data Sources

PubMed, the Cochrane Library, and EMBASE were searched from inception to January 2020.

Study Selection

Studies reporting prognosis of patients with obesity using standard BMI categories and cancer were included. Studies that used nonstandard BMI categories, that were limited to children, or that were limited to patients with hematological malignant neoplasms were excluded. Screening was performed independently by multiple reviewers. Among 1892 retrieved studies, 203 (17%) met inclusion criteria for initial evaluation.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were reporting guideline was followed. Data were extracted by multiple independent reviewers. Risk of death, cancer-specific mortality, and recurrence were pooled to provide an adjusted hazard ratio (HR) with a 95% CI . A random-effects model was used for the retrospective nature of studies.

Main Outcomes and Measures

The primary outcome of the study was overall survival (OS) in patients with cancer, with and without obesity. Secondary end points were cancer-specific survival (CSS) and progression-free survival (PFS) or disease-free survival (DFS). The risk of events was reported as HRs with 95% CIs, with an HR greater than 1 associated with a worse outcome among patients with obesity vs those without.

Results

A total of 203 studies with 6 320 365 participants evaluated the association of OS, CSS, and/or PFS or DFS with obesity in patients with cancer. Overall, obesity was associated with a reduced OS (HR, 1.14; 95% CI, 1.09-1.19; P < .001) and CSS (HR, 1.17; 95% CI, 1.12-1.23; P < .001). Patients were also at increased risk of recurrence (HR, 1.13; 95% CI, 1.07-1.19; P < .001). Conversely, patients with obesity and lung cancer, renal cell carcinoma, or melanoma had better survival outcomes compared with patients without obesity and the same cancer (lung: HR, 0.86; 95% CI, 0.76-0.98; P = .02; renal cell: HR, 0.74; 95% CI, 0.53-0.89; P = .02; melanoma: HR, 0.74; 95% CI, 0.57-0.96; P < .001).

Conclusions and Relevance

In this study, obesity was associated with greater mortality overall in patients with cancer. However, patients with obesity and lung cancer, renal cell carcinoma, and melanoma had a lower risk of death than patients with the same cancers without obesity. Weight-reducing strategies may represent effective measures for reducing mortality in these patients.

Diabetes mellitus and colorectal carcinoma outcomes: a meta-analysis

OBJECTIVES

The impact of diabetes mellitus (DM) on colorectal cancer (CRC) outcomes remains unknown. We studied this by conducting a meta-analysis to evaluate (1) CRC outcomes with and without DM and (2) treatment patterns.

METHODS

We searched PubMed, EMBASE, Google Scholar, and CINAHL for full-text English studies from 1970 to 12/31/2017. We searched keywords, subject headings, and MESH terms to locate studies of CRC outcomes/treatment and DM. Studies were evaluated by two oncologists. Of 14,332, 48 met inclusion criteria. In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses method, we extracted study location, design, DM definition, covariates, comparison groups, outcomes, and relative risks and/or hazard ratios. We utilized a random-effects model to pool adjusted risk estimates. Primary outcomes were all-cause mortality (ACM), disease-free survival (DFS), relapse-free survival (RFS), and cancer-specific survival (CSS). The secondary outcome was treatment patterns.

RESULTS

Forty-eight studies were included, 42 in the meta-analysis, and 6 in the descriptive analysis, totaling > 240,000 patients. ACM was 21% worse (OR 1.21, 95% CI 1.15-1.28) and DFS was 75% worse (OR 1.75, 95% CI: 1.33-2.31) in patients with DM. No differences were detected in CSS (OR 1.10, 95% CI 0.98-1.23) or RFS (OR 1.12, 95% CI 0.91-1.38). Descriptive analysis of treatment patterns in CRC and DM suggested potentially less adjuvant therapy use in cases with DM and CRC.

CONCLUSIONS

Our meta-analysis suggests that patients with CRC and DM have worse ACM and DFS than patients without DM, suggesting that non-cancer causes of death in may account for worse outcomes.

Bevacuzimab May Be Less Effective in Obese Metastatic Colorectal Cancer Patients

PURPOSE

The purpose of this study was to investigate whether obesity affects survival in metastatic colorectal cancer (mCRC) patients treated with bevacizumab combined with chemotherapy.

METHODS

A total of 563 patients with mCRC who had received first-line chemotherapy in combination with bevacizumab were studied. Patients were grouped as obese (BMI levels > 30) or non-obese (BMI levels < 30). Progression-free survival (PFS) and overall survival (OS) were analyzed. Primary tumor location was also investigated in terms of PFS and OS.

RESULTS

The median age of the patients was 59 years. The non-obese group had longer PFS than the obese group (P = 0.030). The 2-year survival rate of the non-obese group was also significantly higher (P = 0.036). The median PFS of non-obese patients was significantly longer in Kras wild-type patients (10.1 vs. 8.1 months, P = 0.010). Among patients with left-sided primary tumor location, median PFS and OS were significantly higher in the non-obese group (PFS non-obese, 11.5 months; obese, 8.8 months; P = 0.002) (OS non-obese, 29.4 months; obese, 21.4 months; P = 0.026).

CONCLUSIONS

Efficacy of bevacizumab may be lower in obese patients. Among patients with Kras wild-type left-sided tumors treated with bevacizumab-based regimens, the prognosis could be worse for obese patients than that for non-obese patients. There is a need for prospectively designed studies of obese patients to prove the efficacy and dosages of bevacizumab in treatment of mCRC.

3'-hydroxy-4'-methoxy-β-methyl-β-nitrostyrene inhibits tumorigenesis in colorectal cancer cells through ROS-mediated DNA damage and mitochondrial dysfunction

The β-nitrostyrene family has been shown to suppress cell proliferation and induce apoptosis in types of various cancers. However, the mechanisms underlying the anticancer effects of β-nitrostyrenes in colorectal cancer remain poorly understood. In this study, we synthesized a β-nitrostyrene derivative, CYT-Rx20 (3'-hydroxy-4'-methoxy-β-methyl-β-nitrostyrene), and investigated its anticancer activities in human colorectal cancer cells both in vitro and in vivo. Our findings showed that treatment with CYT-Rx20 reduced cell viability and induced DNA damage in colorectal cancer cells. In addition, CYT-Rx20 induced cell cycle arrest of colorectal cancer cells at the G2/M phase and upregulated the protein expression of phospho-ERK, cyclin B1, phospho-cdc2 (Tyr15), aurora A, and aurora B, while it downregulated the expression of cdc25A and cdc25C. Furthermore, we found that CYT-Rx20 caused accumulation of intracellular reactive oxygen species (ROS) and reduction of mitochondrial membrane potential. The effects of CYT-Rx20 on cell viability, DNA damage, and mitochondrial membrane potential were reversed by pretreatment with the thiol antioxidant N-acetyl-L-cysteine (NAC), suggesting that ROS-mediated DNA damage and mitochondrial dysregulation play a critical role in these events. Finally, the nude mice xenograft study showed that CYT-Rx20 significantly reduced tumor growth of implanted colorectal cancer cells accompanied by elevated protein expression of aurora A, aurora B, γH2AX, phosphor-ERK, and MDA in the tumor tissues. Taken together, these results suggest that CYT-Rx20 may potentially be developed as a novel β-nitrostyrene-based anticancer agent for colorectal cancer.

Incidence and risk of hypertension with bevacizumab in non-small-cell lung cancer patients: a meta-analysis of randomized controlled trials

Aim

A study was conducted to determine the overall risk and incidence of hypertension with bevacizumab in non-small-cell lung cancer (NSCLC) patients.

Materials and methods

Electronic databases such as the Embase, PubMed, and Cochrane Library were searched for related trials. Statistical analyses were conducted to calculate the overall incidence rates, odds ratios (ORs), and 95% confidence intervals (CIs) by using either random-effect or fixed-effect models depending on the heterogeneity.

Results

A total of 3,155 subjects from nine studies were included. The overall incidences of all-grade and high-grade hypertension in NSCLC patients were 19.55% (95% CI 10.17%–34.3%) and 6.95% (95% CI 5.81%–8.30%). Bevacizumab use was associated with a significantly increased risk in all-grade hypertension (OR 8.07, 95% CI 3.87–16.85; P=0.0002) and high-grade hypertension (OR 5.93, 95% CI 3.41–10.32; P<0.0001). No evidence of publication bias was determined for the ORs of hypertension in our meta-analysis.

Conclusion

Bevacizumab is associated with a significantly increased risk of hypertension development in NSCLC patients. Early monitoring and effective management of hypertension might be important steps for the safe use of this drug.

Association of BMI with overall survival in patients with mCRC who received chemotherapy versus EGFR and VEGF-targeted therapies

Although a raised body mass index (BMI) is associated with increased risk of colorectal cancer (CRC) and recurrence after adjuvant treatment, data in the metastatic setting is limited. We compared overall survival (OS) across BMI groups for metastatic CRC, and specifically examined the effect of BMI within the group of patients treated with targeted therapies (TT). Retrospective data were obtained from the South Australian Registry for mCRC from February 2006 to October 2012. The BMI at first treatment was grouped as underweight <18.5 kg/m², Normal = 18.5 to <25 kg/m², Overweight = 25 to <30 kg/m², Obese I = 30 to <35 kg/m², Obese II ≥35 kg/m². Of 1174 patients, 42 were underweight, 462 overweight, 175 Obese I, and 77 Obese II. The OS was shorter for patients who were underweight and overweight compared to normal (OS 13.7 and 22.3 vs. 24.1 months, respectively, hazard ratio [HR] 2.21 and 1.23). The adjusted median OS was longer for normal versus overweight or obese I patients receiving chemotherapy + targeted therapy (35.7 vs 25.1 or 22.8 months, HR 1.59 and 1.63, respectively) with no difference in OS for chemotherapy alone. On breakdown by type of targeted therapy, overweight and obese I patients had a poorer outcome with Bevacizumab. The BMI is predictive of a poorer outcome for underweight and overweight patients in the whole population. Of those receiving chemotherapy and targeted therapy, BMI is an independent predictor for OS for overweight and obese I patients, specifically for those treated with Bevacizumab. Patients who are overweight or obese (group I) may be a target group for lifestyle and nutrition advice to improve OS with TT.