Prognostic factors and survival in stomach cancer - analysis of 15 years of data from a referral hospital in iran and evaluation of international variation

Prognostic Significance of Preoperative and Postoperative Plasma Levels of Ghrelin in Gastric Cancer: 3-Year Survival Study

OBJECTIVES:

We aimed to investigate prognostic effects of plasma levels of ghrelin before and after gastrectomy in gastric cancer (GC).

METHODS:

We followed 81 GC patients up to 3 years in this study. They were candidates for curative gastrectomy with or without neoadjuvant chemotherapy. Plasma levels of total and active ghrelins before and after the operation were assessed. Association of plasma levels of ghrelin with survival were assessed and adjusted for other potential prognostic factors using Cox regression analyses.

RESULTS:

Both total and active ghrelins dropped after gastrectomy (P<0.001 for both). Multiple Cox models revealed worse survival for patients with postoperative total ghrelins below median (hazards ratio (HR)=2.33, 95% confidence interval (CI): 1.01–5.41) or 25th percentile (HR=4.29, 95% CI: 1.48–12.44) compared with patients with higher ghrelin levels. In case of preoperative total ghrelin, patients with either second or third quartiles of plasma ghrelin showed worse survival compared with patients with the lowest quartile (HR=2.67, 95% CI: 1.11–6.38 for second quartile, and HR=2.32, 95% CI: 1.01–5.35 for third quartile vs. the lowest quartile). However, there was no difference between patients with the highest and lowest quartiles (HR=0.78, 95% CI: 0.22–2.73). Similar pattern was observed for preoperative active ghrelin (HR=4.92, 95% CI: 1.80–13.54 for second quartile, and HR=2.87, 95% CI: 1.11–7.38 for third quartile vs. the lowest quartile). Advanced TNM stage (HR=4.88, 95% CI: 1.10–21.77), cachexia (HR=2.99, 95% CI: 1.35–6.63), and receiving no neoadjuvant chemotherapy (HR=2.02, 95% CI: 1.04–3.92) were other poor prognostic factors.

CONCLUSIONS:

Preoperative and postoperative plasma levels of ghrelin could predict survival of GC patients with different patterns. This prognostic effect was independent of stage and cachexia. Measurement of plasma ghrelin in GC patients could complement conventional staging for more precise risk-stratification of the patients. Extrinsic admirations of ghrelin after total gastrectomy has potentials to improve survival of GC patients.

Retinoid receptors in gastric cancer: expression and influence on prognosis

BACKGROUND

Gastric cancer is frequently lethal despite aggressive multimodal therapies, and new treatment approaches are therefore needed. Retinoids are potential candidate drugs: they prevent cell differentiation, proliferation and malignant transformation in gastric cancer cell lines. They interact with nuclear retinoid receptors (the retinoic acid receptors [RARs] and retinoid X receptors [RXRs]), which function as transcription factors, each with three subclasses, α, β and γ. At present, little is known about retinoid expression and influence on prognosis in gastric cancers.

PATIENTS AND METHODS

We retrospectively analyzed the expression of the subtypes RARα, RARβ, RARγ, RXRα, RXRβ, RXRγ by immunohistochemistry in 147 gastric cancers and 51 normal gastric epithelium tissues for whom clinical follow-up data were available and correlated the results with clinical characteristics. In addition, we quantified the expression of retinoid receptor mRNA using real- time PCR (RT-PCR) in another 6 gastric adenocarcinoma and 3 normal gastric tissues. From 2008 to 2010, 80 patients with gastric cancers were enrolled onto therapy with all-trans-retinoic acid (ATRA).

RESULTS

RARα, RARβ, RARγ and RXRγ positively correlated with each other (p<0.001) and demonstrated significantly lower levels in the carcinoma tissue sections (p<0.01), with lower RARβ, RARγ and RXRα expression significantly related to advanced stages (p<=0.01). Tumors with poor histopathologic grade had lower levels of RARα and RARβ in different histological types of gastric carcinoma (p<0.01). Patients whose tumors exhibited low levels of RARa expression had significantly lower overall survival compared with patients who had higher expression levels of this receptor (p<0.001, HR=0.42, 95.0% CI 0.24-0.73), and patients undergoing ATRA treatment had significantly longer median survival times (p=0.007, HR=0.41, 95.0% CI 0.21-0.80).

CONCLUSIONS

Retinoic acid receptors are frequently expressed in epithelial gastric cancer with a decreased tendency of expression and RARa may be an indicator of a positive prognosis. This study provides a molecular basis for the therapeutic use of retinoids against gastric cancer.