The histological appearance of oesophageal adenocarcinoma—an analysis based on 215 resection specimens

Recent advances in proximal gastric carcinoma

The American Joint Committee on Cancer (AJCC) staging scheme requires staging proximal gastric carcinoma (PGC) as esophageal adenocarcinoma (EAC), which has been shown to be controversial by recent research results. To update the current research findings on PGC, we systematically reviewed and analyzed the scientific evidence on key arguments related to PGC. The data of high-quality research articles showed that PGC arised in the cardiac mucosa in the proximal stomach within 3 cm below the gastroesophageal junction. Its incidence is rising in East Asian countries, but decreasing in the West, and plateaued at a low level in the United States. PGC is a slowly progressive cancer with unknown independent risk factors and the mechanisms of pathogenesis. This carcinoma exhibits a wide histopathological spectrum and heterogeneous post-resection patient survival characteristics, and cannot be adequately staged for prognotic stratification by the current AJCC staging classification. The results on PGC genomics reveal unique genetic profiles, especially in East Asian populations. In conclusion, mounting evidence defies a simple placement of PGC in a single category of EAC for disease classification; further investigations on the mechanisms of PGC pathogenesis are urgently needed.

EBV-infection in cardiac and non-cardiac gastric adenocarcinomas is associated with promoter methylation of p16, p14 and APC, but not hMLH1

BACKGROUND

Epstein-Barr virus (EBV)-associated gastric carcinomas (GC) constitute a distinct clinicopathological entity of gastric cancer. In order to determine underlying distinct aberrant promoter methylation we tested cardiac and non-cardiac GC with regard to the presence of EBV.

METHODS

One hundred GC were tested by RNA-in situ hybridization for the presence of EBV by EBV-encoded small RNA (EBER). Aberrant promoter methylation was investigated by methylation-specific real-time PCR for p16, p14, APC and hMLH1. P16 protein expression was assessed by immunohistochemistry.

RESULTS

In our selected study cohort, EBER-transcripts were detected in 19.6% (18/92) of GC. EBV-positive GC revealed significantly more often gene hypermethylation of p16, p14 and APC (p<0.0001, p<0.0001 and p=0.02, respectively) than EBV-negative GC. The majority of GC with p16 hypermethylation showed a p16 protein loss (22/28). In contrast, no correlation between the presence of EBV and hMLH1 hypermethylation was found (p=0.7). EBV-positive GC showed a trend towards non-cardiac location (p=0.06) and lower stages (I/II) according to the WHO (p=0.05).

CONCLUSIONS

Hypermethylation of tumor suppressor genes is significantly more frequent in EBV-associated GC compared to EBV-negative GC. Our data add new insights to the role of EBV in gastric carcinogenesis and underline that EBV-associated GC comprise a distinct molecular-pathologic as well as a distinct clinicopathological entity of GC.

Esophageal cancer--the five year survivors

BACKGROUND

Esophageal cancer in the United States carries a poor prognosis with overall 5 year survival rate of approximately 10%. Due to this dismal outcome, data analyzing factors predictive of survival for greater than 5 years are not available.

METHODS

Single institution retrospective review of esophageal resection for curative intent from 1984 to 2004. We identified 50 actual 5 year survivors (long term survivors, LTS) out of 266 patients (19%) with invasive esophageal cancer and, using multivariate logistic regression, compared characteristics between the LTS, and short-term (<5 year) survivors (STS).

RESULTS

There was no significant difference in clinical T stage or N stage by EUS (P = 0.81) or in the utilization of neoadjuvant therapy in the LTS versus STS (58% vs. 62%, respectively, P = 0.36). The LTS group was significantly more likely to have pathologic complete response (69% vs. 41%, P < 0.001), lower pathologic T stage, i.e., pT0, pTis, or pT1 (83% vs. 45%, P < 0.001), pN0 stage (97% vs. 68%, P < 0.001), favorable tumor differentiation (well or well to moderate, 39% vs. 13%, P < 0.001), and absence of angiolymphatic (88% vs. 69%, P < 0.01) or perineural invasion (95% vs. 83%, P = 0.04). In comparing the factors predictive of outcome in LTS versus the STS with increasing relative risk, absence of perineural invasion (RR 0.41 (0.27, 0.61)), negative margins (RR 0.41 (0.29, 0.57)), absence of angiolymphatic invasion (RR 0.39 (0.30, 0.51)), pN0 stage (RR 1.37 (1.23, 1.52)), pT0 or pT1 (RR 1.85 (1.64, 2.07)), pathologic complete response (RR 2.02 (1.76, 2.31)), and favorable tumor grade (RR 3.00 (2.49, 3.61)) were associated with improved survival.

CONCLUSION

Tumor biological factors including favorable tumor grade may be the most important influence on 5 year actual survival in esophageal cancer.

Differentiation between pancreaticobiliary and upper gastrointestinal adenocarcinomas: is analysis of cytokeratin 17 expression helpful?

Metastatic adenocarcinoma of unknown primary site, eg, to lymph nodes, liver, or lung, may originate from many organs. Microscopic differentiation of adenocarcinomas from the pancreaticobiliary and upper gastrointestinal tracts may be difficult because of shared histologic and immunohistologic features. A high prevalence of cytokeratin (CK)17 expression in pancreaticobiliary adenocarcinoma was reported, and preliminary data indicate infrequent or missing expression in gastric adenocarcinoma. The prevalence of CK17 expression in gastric cardiac and esophageal adenocarcinomas has not been studied. We studied CK17 expression in tissue microarrays of 67 distal gastric, 71 gastric cardiac, and 46 esophageal adenocarcinomas and compared it with expression in 55 pancreatic, 23 extrahepatic bile duct, and 49 colorectal adenocarcinomas. CK17 expression was as follows: pancreatic, 88%; bile duct, 59%; esophageal, 30%; distal gastric, 28%; gastric cardiac, 27%; and colorectal adenocarcinoma, 6%. These differences were statistically significant for all tumor types except in comparisons of esophageal, cardiac, and distal gastric adenocarcinoma. The prevalence of CK17 expression in pancreatic and extrahepatic bile duct adenocarcinomas is substantially higher than in upper gastrointestinal tract and colorectal adenocarcinomas. However, in individual cases of adenocarcinoma of unknown primary site, CK17 results alone are insufficient to differentiate the analyzed tumor entities.