Chronic advanced gastric cancer: clinicopathologic analysis of survival data

Prognostic Implication of M2 Macrophages Are Determined by the Proportional Balance of Tumor Associated Macrophages and Tumor Infiltrating Lymphocytes in Microsatellite-Unstable Gastric Carcinoma

Tumor associated macrophages are major inflammatory cells that play an important role in the tumor microenvironment. In this study, we investigated the prognostic significance of tumor associated macrophages (TAMs) in MSI-high gastric cancers using immunohistochemistry. CD68 and CD163 were used as markers for total infiltrating macrophages and M2-polarized macrophages, respectively. The density of CD68+ or CD163+ TAMs in four different areas (epithelial and stromal compartments of both the tumor center and invasive front) were analyzed in 143 cases of MSI-high advanced gastric cancers using a computerized image analysis system. Gastric cancers were scored as "0" or "1" in each area when the density of CD68+ and CD163+ TAMs was below or above the median value. Low density of CD68+ or CD163+ macrophages in four combined areas was closely associated with more frequent low-grade histology and the intestinal type tumor of the Lauren classification. In survival analysis, the low density of CD163+ TAMs was significantly associated with poor disease-free survival. In multivariate survival analysis, CD163+ TAMs in four combined areas, stromal and epithelial compartments of both tumor center and invasive front were independent prognostic indicator in MSI-high gastric cancers. In addition, the density of CD163+ TAMs correlated with tumor infiltrating lymphocytes (TILs). Our results indicate that the high density of CD163+ TAMs is an independent prognostic marker heralding prolonged disease-free survival and that the prognostic implication of CD163+ TAMs might be determined by the proportional balance of TAMs and TILs in MSI-high gastric cancers.

Requirement for a standardised definition of advanced gastric cancer

Each year, ~988,000 new cases of stomach cancer are reported worldwide. Uniformity for the definition of advanced gastric cancer (AGC) is required to ensure the improved management of patients. Various classifications do actually exist for gastric cancer, but the classification determined by lesion depth is extremely important, as it has been shown to correlate with patient prognosis; for example, early gastric cancer (EGC) has a favourable prognosis when compared with AGC. In the literature, the definition of EGC is clear, however, there is heterogeneity in the definition of AGC. In the current study, all parameters of the TNM classification for AGC reported in each previous study were individually analysed. It was necessary to perform a comprehensive systematic literature search of all previous studies that have reported a definition of ACG to guarantee homogeneity in the assessment of surgical outcome. It must be understood that the term ‘advanced gastric cancer’ may implicate a number of stages of disease, and studies must highlight the exact clinical TNM stages used for evaluation of the study.

Higher intratumoral expression of CD1a, tryptase, and CD68 in a follicular variant of papillary thyroid carcinoma compared to adenomas: correlation with clinical and pathological parameters

BACKGROUND

In a number of human malignancies, the presence of lymphocytic infiltration in or around tumor tissue is commonly considered to be part of the host tumor immune response. An association between thyroid carcinoma and chronic inflammation has been described. This relationship is not fully understood, so we performed a systematic study on a follicular variant of papillary thyroid carcinoma (FVPTC), to evaluate the type and distribution of certain immunological cells and their relationship with prognostic factors.

METHODS

We selected 91 consecutive cases of FVPTC, in which we evaluated the presence of three different immunological cells: dendritic cells (DC), immature CD1a+ and mature DC-Lamp+; mast cells (MC), tryptase+; and macrophages (M), CD68+, in the intratumoral, peritumoral, and extratumoral areas. As a control we analyzed 44 cases of thyroid adenomas (A).

RESULTS

In the intratumoral and peritumoral areas, the expression of CD1a, tryptase, and CD68 was significantly higher in FVPTC than in adenomas. Expression of CD1a and tryptase was comparable in the extratumoral compartment, whereas CD68 expression in the extratumoral area was significantly higher in FVPTC than in adenoma (p=0.0015). DC-Lamp expression was not significantly different among the intra-tumor, peri-tumor, and extra-tumor areas of FVPTC or adenoma. It was also very interesting that nonencapsulated FVPTC were more positive to tryptase.

CONCLUSION

We highlight a higher presence of immunological cells in carcinomas than in adenomas. On this basis, it is possible to speculate that these inflammatory elements could be involved in tumor progression and invasion, as appears to be the case for MC and M.

Double contrast-enhanced ultrasonography evaluation of preoperative Lauren classification of advanced gastric carcinoma

INTRODUCTION

The clinical value of double contrast-enhanced ultrasonography (DCUS) in determining the Lauren classification of advanced gastric carcinoma needed investigation.

MATERIAL AND METHODS

Fifty-eight patients with gastric cancer proved by endoscopic biopsy underwent preoperative DCUS examination in which an oral contrast agent was combined with an intravenous agent, and the findings were compared with the postoperative pathological findings using haematoxylin-eosin and Alcian Blue-Periodic Acid Schiff (AB-PAS) staining.

RESULTS

Of 58 patients, 34 (59%) were the intestinal type and 24 (41%) the diffuse type on pathological examination of resected specimens. Among intestinal type patients, 30 (88%) showed homogeneous vascular enhancement and 4 (12%) heterogeneous enhancement with the "sandwich" pattern in 2 patients (50%) and "barrier" pattern in 2 patients (50%). In the diffuse type, 22 of 24 patients (92%) enhanced heterogeneously, with stippled and peripheral enhancement in 9 (41%), the "sandwich" pattern in 8 (36%) and "barrier" pattern in 5 (23%). Two of 24 patients (8%) with the diffuse type enhanced homogeneously. The proportion of heterogeneous enhancement was significantly different between the 2 subtypes of tumour (p = 0.0001). The sensitivity and specificity of heterogeneous enhancement in diagnosing the diffuse type of advanced gastric cancer were 92% and 88%, respectively. Youden's index was 0.8.

CONCLUSIONS

Double contrast-enhanced ultrasonography is a new and useful method to determine Lauren classification in patients with gastric carcinoma.

The enigma of Helicobacter pylori infection and gastric cancer

Although H. pylori has been recognized as a class I carcinogen, incongruence between infection prevalence and cancer incidence has been reported. Holcombe called attention to the high prevalence of infection in the face of low cancer rates, which he called "The African Enigma". Similar observations have now been made in other geographic areas. Gastric carcinoma should be considered an infectious disease, for which the classical epidemiologic model of causality applies. The model proposes that tissue injury inflicted by the infectious agent is modulated by its interactions with host and environmental factors. Although approximately half of the world's population is infected, only a small proportion of people develop cancer. The African enigma is a striking example of the major contrasts in cancer risk among populations with similarly high prevalence of infection. The mechanisms involved in reducing the risk of cancer in infected individuals are explored in this article, which may lead to the design of effective prevention strategies.

Incidence and survival of stomach cancer in a high-risk population of Chile

AIM: To study the incidence and survival rate of stomach cancer (SC) and its associated factors in a high risk population in Chile.

METHODS: The population-based cancer registry of Valdivia, included in the International Agency for Research on Cancer system, covers 356 396 residents of Valdivia Province, Southern Chile. We studied all SC cases entered in this Registry during 1998-2002 (529 cases). Population data came from the Chilean census (2002). Standardized incidence rates per 100 000 inhabitants (SIR) using the world population, cumulative risk of developing cancer before age 75, and rate ratios by sex, age, ethnicity and social factors were estimated. Relative survival (Ederer II method) and age-standardized estimates (Brenner method) were calculated. Specific survival rates (Kaplan-Meier) were measured at 3 and 5 years and survival curves were analyzed with the Logrank and Breslow tests. Survival was studied in relation to demographics, clinical presentation, laboratory results and medical management of the cases. Those variables significantly associated with survival were later included in a Cox multivariate model.

RESULTS: Between 1998 and 2002, 529 primary gastric cancers occurred in Valdivia (crude incidence rate 29.2 per 100 000 inhabitants). Most cases were male (69.0%), residents of urban areas (57.5%) and Hispanic (83.2%), with a low education level (84.5% < 8 school years). SC SIR was higher in men than women (40.8 and 14.8 respectively, P < 0.001), risk factors were low education RR 4.4 (95% CI: 2.9-6.8) and 1.6, (95% CI: 1.1-2.1) for women and men respectively and Mapuche ethnicity only significant for women (RR 2.2, 95% CI: 1.2-3.7). Of all cases, 76.4% were histologically confirmed, 11.5% had a death certificate only (DCO), 56.1% were TNM stage IV; 445 cases (84.1%) were eligible for survival analysis, all completed five years follow-up; 42 remained alive, 392 died of SC and 11 died from other causes. Specific 5-year survival, excluding cases with DCO, was 10.6% (95% CI: 7.7-13.5); 5-year relative survival rate was 12.3% (95% CI: 9.1-16.1), men 10.9% (95% CI: 7.4-15.2) and women 16.1% (95% CI: 9.5-24.5). Five-year specific survival was higher for patients aged < 55 years (17.3%), with intestinal type of cancer (14.6%), without metastasis (22.2%), tumor size < 4 cm (60.0%), without lymphatic invasion (77.1%), only involvement of the mucous membrane (100%). Statistically significant independent prognostic factors were: TNM staging, diffuse type, metastasis, supraclavicular adenopathy, palpable tumor, and hepatitis or ascites.

CONCLUSION: Social determinants are the main risk factors for SC, but not for survival. An advanced clinical stage at consultation is the main cause of poor SC survival.