Features of cancer management in obese patients

Sarcopenia and obesity among patients with soft tissue sarcoma - Association with clinicopathologic characteristics, complications and oncologic outcome: A systematic review and meta-analysis

BACKGROUND AND AIMS

Sarcopenia and obesity may be associated with negative outcomes in many cancers, but their prevalence and impact in modern regimens for soft-tissue sarcoma (STS) have not been systematically studied. This study summarises and critically evaluates the current evidence-based literature on body mass index (BMI) and body composition among patients with STS, with respect to clinical and pathologic characteristics, treatment-associated morbidity and oncologic outcome.

METHODS

A systematic literature search of the PubMed, Embase and Cochrane databases was performed. Meta-analysis of the relationship between BMI, body composition and pathologic characteristics, operative morbidity and oncologic outcome was undertaken using RevMan v.5.4 using fixed or random effects methods as appropriate.

RESULTS

14 studies including 3598 patients met inclusion criteria. Ten studies reported on BMI, two on CT and two on PET-CT assessment of body composition. BMI ranged from 14.6 to 63.7 kg/m², with obesity in 18%-39% of patients. Although some studies demonstrated larger tumours among patients with obesity, this was not significant on meta-analysis (P = 0.31, I² = 99%). There was no significant difference in tumour grade or histologic type according to BMI. Postoperatively, obesity was associated with increased risk of overall morbidity (odds ratio (OR) 2.03 [95% CI 1.41-2.92], P = 0.0001, I² = 22%), and wound morbidity (OR 1.32 [95% CI 1.02-1.71], P = 0.03, I² = 0%). Similar effects were observed in studies of visceral adiposity. No differences in functional outcomes were observed. There was a trend towards reduced local recurrence among patients with obesity (HR 0.64 [95% CI 0.38-1.08], P = 0.10, I² = 0%), but no difference in distant metastasis (HR 1.00 [95% CI 0.76-1.30], P = 0.98, I² = 0%) or overall survival (HR 0.98 [95% CI 0.43-2.22], P = 0.95, I² = 64%). Various measures of sarcopenia were associated with poorer survival outcomes.

CONCLUSION

While obesity is associated with increased postoperative morbidity, it had no significant association with long-term oncologic outcomes. Sarcopenia may be associated with a poorer long-term prognosis. A greater understanding of the impact of nutritional status on disease characteristics and treatment outcomes is essential to facilitate improvements in clinical care for patients with STS.

The Effect of an Asymmetric Energy Window on Bone Scintigraphy Image Quality

Bone scintigraphy is one of the most common nuclear medicine tests. Previous work investigated the effectiveness of an asymmetric window (ASW) for planar bone scintigraphy using simulation and phantom data. Phantom studies concluded that the ASW improved both the resolution and the contrast-to-noise ratio when imaging objects with high scatter. The aim of this study was to confirm this improvement increased image quality in patients. This study also investigated whether the differences between a symmetric window (SW) and an ASW depended on body mass index. Methods: Fifty-eight patients had 2 scans: a standard scan using an SW of 140 keV ± 10% and a scan using an ASW of 140 keV + 10% and - 7.5%. Three readers independently compared the 2 image sets and scored them using a 5-score scale (ranging from 1 = ASW better [clinically important] to 5 = SW better [clinically important]). Scores from all radiologists were pooled and analyzed statistically. A P value of less than 0.05 was considered statistically significant. Results: In 93 cases (53%), the readers scored the ASW images better than the SW images. In 5 cases (3%), the ASW images were preferred, with the difference considered clinically important; there were no cases in which the SW was similarly preferred. For the sign test, we determined whether the total of 93 scores of 1 or 2 (ASW preferred) was significantly different from the 15 scores of 4 or 5 (SW preferred). The P value was less than 0.00001, demonstrating that the difference was significant. Conclusion: In patients undergoing bone scintigraphy, ASW provided an improvement in image quality that in some cases was judged clinically important.

Obesity is associated with larger soft-tissue sarcomas, more surgical complications, and more complex wound closures (obesity leads to larger soft-tissue sarcomas)

BACKGROUND AND OBJECTIVES

Does a link exist between obesity and soft-tissue sarcoma outcomes? We hypothesized that soft-tissue sarcomas in patients with obesity may lead to larger tumors at detection, with an increased risk for a more complex surgical excision, wound healing-related complications, higher stage at presentation, and decreased survival.

METHODS

One hundred thirty-nine and patients with soft-tissue sarcoma were retrospectively evaluated over 10 years. Patients were divided into 2 cohorts based on the World Health Organization body mass index (BMI) obesity grouping. A BMI ≥ 30 kg/m² was classified as obese and a BMI < 30 kg/m² was classified as nonobese.

RESULTS

Eighty-five nonobese and 54 obese individuals were evaluated. The median tumor diameter was 50% larger (P = .024) and the overall complication rate was 1.7-fold higher in patients with obesity (P = .0032). Patients with obesity also had a statistically significantly higher rate of complex wound closures. In multivariable logistic regression, obesity remained a highly significant factor favoring complications after the surgical treatment of soft-tissue sarcoma (odds ratio = 3.66, 95% confidence interval = 1.54-8.71; P = .0033). No statistically significant differences were noted on comparing groups for the incidence of metastatic spread or survival.

CONCLUSIONS

These findings suggest that obesity is associated with larger tumors, a higher incidence of wound complications, and greater use of complex wound-closure methods.