Correlation between metastatic site, histological type, and serum tumor markers of gastric carcinoma

Consensus on the pathological definition and classification of poorly cohesive gastric carcinoma

BACKGROUND AND AIMS

Clinicopathological characteristics of gastric cancer (GC) are changing, especially in the West with a decreasing incidence of distal, intestinal-type tumours and the corresponding increasing proportion of tumours with Laurén diffuse or WHO poorly cohesive (PC) including signet ring cell (SRC) histology. To accurately assess the behaviour and the prognosis of these GC subtypes, the standardization of pathological definitions is needed.

METHODS

A multidisciplinary expert team belonging to the European Chapter of International Gastric Cancer Association (IGCA) identified 11 topics on pathological classifications used for PC and SRC GC. The topics were debated during a dedicated Workshop held in Verona in March 2017. Then, through a Delphi method, consensus statements for each topic were elaborated.

RESULTS

A consensus was reached on the need to classify gastric carcinoma according to the most recent edition of the WHO classification which is currently WHO 2010. Moreover, to standardize the definition of SRC carcinomas, the proposal that only WHO PC carcinomas with more than 90% poorly cohesive cells having signet ring cell morphology have to be classified as SRC carcinomas was made. All other PC non-SRC types have to be further subdivided into PC carcinomas with SRC component (< 90% but > 10% SRCs) and PC carcinomas not otherwise specified (< 10% SRCs).

CONCLUSION

The reported statements clarify some debated topics on pathological classifications used for PC and SRC GC. As such, this consensus classification would allow the generation of evidence on biological and prognostic differences between these GC subtypes.

Clinical Assessment and Prognostic Evaluation of Tumor Markers in Patients with Gastric Cancer

Aim

To investigate the relationship between the serum levels of CEA, CA19-9, CA24-2, CA72-4, and AFP in patients with gastric cancer (GC) and their clinicopathological characteristics; to analyze the efficacy of these tumor markers in evaluating the prognosis of GC.

Methods

Overall, 389 patients with GC either located in the gastric cardia (132), the pyloric antrum (112) or the body of the stomach (145) were included in the study. Serum levels of CEA, CA19-9, CA72-4, and AFP were detected with the ECLIA method, while CA24-2 was measured with ELISA.

Results

First, the serum level of CEA in GC patients with a cardia-located cancer was significantly higher than in patients with pyloric antrum-located cancer (p=0.050). CA72-4 level in patients with GC located in the gastric body was significantly higher than in patients with cardia and pyloric antrum-located cancers (p=0.042 and p=0.039, respectively). Secondly, serum CA19-9 and CA24-2 levels in females with cardia-located GC were significantly higher than those in males with the same type of tumor (p=0.037 and p=0.033, respectively). Additionally, for females with gastric body-located GC the levels of CEA and CA72-4 were significantly higher than those in male patients with the same type of tumor (p=0.047 and p=0.048, respectively). Conversely, in female GC patients with pyloric antrum-located cancer the serum levels of CA19-9 and CA24-2 were significantly lower than those in male patients with the same type of cancer (p=0.013 and p=0.007, respectively). Moreover, CEA, CA19-9, CA24-2, and CA72-4 levels were strongly related to TNM grade and histological anatomy stage, whereas CEA and CA72-4 levels were strongly related to lymph node stage (p=0.000 and p=0.042, respectively). Patients with vascular embolism had higher serum levels of CEA, CA19-9, CA24-2, and CA72-4 compared with patients without vascular embolism (p=0.005, p=0.031, p=0.007, and p=0.014, respectively). In patients with distant metastases and ascites the levels of CEA, CA19-9, and CA24-2 were higher than in patients without these conditions (p=0.003, p=0.001, p=0.001, p=0.016, p= 0.011, and p=0.030, respectively). Serum CEA, CA19-9, and CA24-2 levels showed correlations with tumor invasive depth and growth types (p=0.001, p=0.040, and p=0.035, respectively). Patients with lump and catheter tumor growth types had significantly higher AFP levels than patients with invasion and anabrosis growth types (p=0.034 and p=0.005, respectively). Tumor size was correlated with the preoperative serum levels of CEA, AFP, and CA72-4 (p=0.007, p=0.020, and p=0.008, respectively). Additionally multiple linear regression analysis showed that preoperative levels of CEA and CA72-4 were correlated to TNM stages, CA19-9 and CA24-2 levels were correlated to both gender and distant metastasis, and AFP was correlated only to ascites. During follow-up there were 115 deaths. Median survival time for GC patients with negative preoperative CEA was 18.07 months, and was 10.97 months for patients with preoperative CEA positive levels (p=0.0005). Similarly, the median survival time for GC patients with negative preoperative CA72-4 was 33.60, and was 16.03 months for patients with preoperative CA72-4 positive levels (p=0.0041).

Conclusions

The preoperative levels of CEA, CA19-9, CA24-2, CA72-4, and AFP were closely related to TNM grade, gender, distant metastasis and ascites. These makers seem to play important roles in predicting recurrence and metastasis, and in evaluating prognosis.

Human epididymis protein 4 immunostaining of malignant ascites differentiates cancer of Müllerian origin from gastrointestinal cancer

BACKGROUND

An accurate diagnosis of cancer of Müllerian origin is required before the initiation of treatment. An overlap in clinical presentation and cytological, histological, or imaging studies with other nongynecological tumors does occur. Therefore, immunocytochemistry markers are used to determine tumor origin. Human epididymis protein 4 (HE4) is overexpressed in tissue of epithelial ovarian cancer (EOC). It has shown to be a sensitive and specific serum marker for EOC and to be of value for the differentiation between EOC and ovarian metastases of gastrointestinal origin. The objective of the current study was to evaluate HE4 immunocytochemistry in malignant ascites for differentiation between cancer of Müllerian origin, including EOC, and adenocarcinomas of the gastrointestinal tract.

METHODS

Cytological specimens of 115 different adenocarcinomas (45 EOCs, 46 cases of gastric cancer, and 24 cases of colorectal cancer) were stained for HE4, paired box 8 (PAX8), and other specific markers.

RESULTS

91% of the ascites samples from patients with EOC stained for both HE4 and PAX8. The 4 samples without HE4 staining were a clear cell carcinoma, a low-grade serous adenocarcinoma, an undifferentiated adenocarcinoma, and a neuroendocrine carcinoma. All high-grade serous adenocarcinomas (n = 37, 100%) stained with HE4, compared with 94% that stained positively for PAX8. In cases of gastric or colorectal cancer, 25% and 21% of cases, respectively, stained positive for HE4. No PAX8 staining was observed in colorectal or gastric adenocarcinomas.

CONCLUSIONS

HE4 staining in ascites is feasible and appears to have a high sensitivity for high-grade serous ovarian cancer. HE4 is a useful addition to the current panel of immunocytochemistry markers for the diagnosis of EOC and for differentiation with gastrointestinal adenocarcinomas. Cancer Cytopathol 2017;125:197-204. © 2016 American Cancer Society.

The characteristics of the serum carcinoembryonic antigen and carbohydrate antigen 19-9 levels in gastric cancer cases

PURPOSE

Although carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 are the most commonly used tumor markers in gastric cancer, the differences in the characteristics of these two markers remain unclear, because most previous studies have included many patients who were positive for both markers.

METHODS

We analyzed the available data on 1050 patients with gastric cancer who underwent R0 resection. The background characteristics and recurrence-free survivals (RFS) were compared between the single-positive patients for CEA or CA 19-9 and double-negative patients.

RESULTS

Among these 1050 patients, 86 patients (8.2 %) were positive for CEA only, 77 patients (7.3 %) were positive for CA 19-9 only, and 867 patients (82.6 %) were double negative for both markers. Patients who were elderly, male and had a differentiated histology were more commonly observed in the CEA-positive group than in the double-negative group (P = 0.004, P = 0.009, and P = 0.001). The patients who were positive for either CEA or CA 19-9 had a significantly worse RFS than the patients who were negative for both (P < 0.001 and P < 0.001). The most frequent site of recurrence was the liver (9.3 %) in the CEA-positive group and the peritoneum (11.7 %) in the CA 19-9-positive group.

CONCLUSION

Age, sex, and histological type were thus found to be associated with CEA positivity. CEA is, therefore, considered to be a sensitive marker for liver recurrence, while CA 19-9 is a sensitive marker for peritoneal recurrence.

The presence of metastases in regional lymph nodes is associated with tumor size and depth of invasion in sporadic gastric adenocarcinoma

BACKGROUND

Gastric adenocarcinoma is more often found in men over 50 years in the form of an antral lesion. The tumor has heterogeneous histopathologic features and a poor prognosis (median survival of 15% in five years).

AIM

To estimate the relationship between the presence of nodal metastasis and other prognostic factors in sporadic gastric adenocarcinoma.

METHOD

Were evaluated 164 consecutive cases of gastric adenocarcinoma previously undergone gastrectomy (partial or total), without clinical evidence of distant metastasis, and determined the following variables: topography of the lesion, tumor size, Borrmann macroscopic configuration, histological grade, early or advanced lesions, Lauren histological subtype, presence of signet ring cell, degree of invasion, perigastric lymph node status, angiolymphatic/perineural invasion, and staging.

RESULTS

Were found 21 early lesions (12.8%) and 143 advanced lesions (87.2%), with a predominance of lesions classified as T3 (n=99/60, 4%) and N1 (n=62/37, 8%). The nodal status was associated with depth of invasion (p<0.001) and tumor size (p<0.001). The staging was related to age (p=0.048), histological grade (p=0.003), and presence of signet ring cells (p = 0.007), angiolymphatic invasion (p = 0.001), and perineural invasion (p=0.003).

CONCLUSION

In gastric cancer, lymph node involvement, tumor size and depth of invasion are histopathological data associated with the pattern of growth/tumor spread, suggesting that a wide dissection of perigastric lymph nodes is a fundamental step in the surgical treatment of these patients.

TNFAIP8 overexpression is associated with lymph node metastasis and poor prognosis in intestinal-type gastric adenocarcinoma

AIMS

Tumour necrosis factor alpha-induced protein 8 (TNFAIP8) is implicated in the progression of several human malignancies, but its role in gastric adenocarcinoma is unknown. TNFAIP8 expression and its correlation with clinical significance in gastric adenocarcinoma are evaluated in this study.

METHODS AND RESULTS

The expression of TNFAIP8 was determined in primary gastric adenocarcinoma tissues using immunohistochemistry (IHC) and Western blotting analysis. TNFAIP8 expression was higher in gastric adenocarcinoma tissues. Elevated expression of TNFAIP8 in gastric adenocarcinoma was associated significantly with depth of invasion (P = 0.024), lymph node metastasis (P = 0.038) and Lauren classification (P = 0.048). Patients with tumours showing high TNFAIP8 expression had a significantly poorer overall survival (OS) and disease-free survival (DFS) than those with low TNFAIP8 expression in intestinal-type gastric adenocarcinoma (IGA) (P = 0.001 for both). In the multivariate Cox analysis, TNFAIP8 expression was an independent prognostic marker for OS and DFS in IGA with P-values of 0.006 and 0.007, respectively.

CONCLUSIONS

Our data suggest that TNFAIP8 overexpression may contribute to lymph node metastasis and poor prognosis in IGA.

Preoperative serum tumor marker levels in gastric cancer

OBJECTIVE

Tumor markers have shown little benefit as a method for screening. However, they can be used clinically for the monitoring of tumor recurrence and used as prognostic factors because higher levels have been observed in advanced disease. This study aimed to investigate the relationship between the preoperative tumor marker levels and different clinical aspects of gastric cancer.

METHODS

One hundred and six consecutive patients with confirmed diagnosis of gastric cancer and 106 subjects (age and sex matched) with no malignancy as control group were included prospectively in this study in 3 years. The relationships between tumor markers CEA, CA 19-9 and stage of disease, tumor differentiation, presence of ringlet cell type, presence of peritoneal carcinomatozis were investigated.

RESULTS

The serum CEA and CA 125 levels were found to be significantly elevated in gastric cancer patients than in controls. The serum level of CEA had showed a significant elevation with the presence of distant metastasis. The CA 19-9 and CA 125 levels had showed significant elevations with the presence of peritoneal carcinomatozis. Conclusions : This study showed that there is a limited clinical benefit of preoperative tumor marker measurements in gastric cancer such as estimation of peritoneal dissemination.

Expression and prognostic significance of gastric-specific annexin A10 in diffuse- and intestinal-type gastric carcinoma

BACKGROUND AND AIMS

Annexin A10 (ANXA10) and its liver-specific short isoform (ANXA10S) had tissue-restricted expression. The downregulation of ANXA10S is correlated with tumor progression and poor prognosis in hepatocellular carcinoma. The aim of the present study was to validate the tissue distribution and explore the role of the ANXA10 protein expression in gastric carcinoma.

METHODS

We examined the ANXA10 protein expression in human and animal tissues and 356 resected primary gastric carcinomas, using specific mouse and rabbit polyclonal antibodies, by immunohistochemical staining.

RESULTS

The ANXA10 protein is a nuclear protein specifically expressed in fetal and adult gastric mucosa and Brunner's gland across species, including humans, minipigs, woodchucks, and mice, and is commonly lost in gastric mucosa with intestinal metaplasia. The ANXA10 protein was expressed in 43.5% (155 cases) of gastric carcinomas; 74.2% (98/132) in the diffuse-type gastric carcinoma (DGC), 73.7% (28/38) in the mixed-type gastric carcinoma, and significantly lower in the intestinal-type gastric carcinoma (IGC) and indeterminate groups, 16.8% (28/167) and 5.3% (1/19), respectively (P<1×10(-8)). IGC with ANXA10 expression was correlated with a higher stage (P=0.049), particularly higher in stage IIIA/IIIB/IV IGC than lower-stage (IA/IB/II) tumors (P=0.005), but was not correlated with age, sex, and nodal status. In contrast, DGC with ANXA10 expression was associated with younger age, female patients, and importantly, lower tumor stage and lymph node metastasis (P=0.007, P=0.065, P=0.024, and P=0.0014, respectively). Moreover, DGC with ANXA10 expression had a better 5-year patient survival (P=0.0048), whereas IGC with ANXA10 expression had a lower 5-year survival (P=0.034).

CONCLUSIONS

The ANXA10 protein expression is a novel marker of gastric differentiation, and is differentially expressed in IGC and DGC, with opposite prognostic significance.

Role of serum tumor markers in monitoring for recurrence of gastric cancer following radical gastrectomy

It has been suggested that the serum tumor markers AFP, CEA, and CA19-9 may serve as prognostic factors or indicators for recurrence after radical gastrectomy for gastric cancer. We compared the value of these markers in a group with (n=52) and a group without recurrent gastric cancer (n=52) according to the site of recurrence. Serum levels of tumor markers were measured at the time of preoperative diagnosis and at follow-up. At least one tumor marker was positive preoperatively in 20 with recurrence vs. 7 controls (p=0.007). The peritoneum was the most common recurrent site. The positive predictive value of AFP was high at the time of diagnosis and CA19-9 positivity was high at the time of recurrence. Positive CEA suggested recurrence to the liver. In summary, an elevated tumor marker at diagnosis or during follow up may identify patients at higher risk for a recurrence. CA19-9 may be especially useful as a marker for peritoneal recurrence of the gastric cancer, and CEA for recurrence to liver.

Expression of carbonic anhydrase IX (CA IX), a hypoxia-related protein, rather than vascular-endothelial growth factor (VEGF), a pro-angiogenic factor, correlates with an extremely poor prognosis in esophageal and gastric adenocarcinomas

OBJECTIVE

To evaluate the expression of carbonic anhydrase IX (CA IX) and vascular-endothelial growth factor (VEGF) in esophageal and gastric adenocarcinomas and in turn with the histologic subtype.

SUMMARY BACKGROUND DATA

Tumor hypoxia is an important factor in therapy resistance. A low oxygen concentration in tumors stimulates a.o. the expression of CA IX, a marker of hypoxia, and VEGF, a pro-angiogenic factor.

METHODS

We evaluated the immunohistochemical expression of CA IX and VEGF on paraffin-embedded material of 154 resection specimens: 39 esophageal, 73 cardiac, and 42 distal gastric adenocarcinomas (UICC classification). The adenocarcinomas were subtyped according to the Lauren classification (intestinal- and diffuse-type).

STATISTICAL ANALYSIS

chi test, Kaplan-Meier survival analysis, log-rank test, and Cox proportional hazards model.

RESULTS

CA IX and VEGF expression were independent of the localization of the tumor. However, intestinal-type adenocarcinomas showed a significantly higher expression of CA IX as well as VEGF than diffuse-type tumors. VEGF expression was associated with a high microvessel density. Although survival analysis showed that CA IX expression (P = 0.008) as well as the coexpression of CA IX and VEGF (P = 0.008) correlate with a poor outcome, only CA IX expression is an independent prognostic factor for overall survival and metastasis-free survival.

CONCLUSION

The difference in expression of CA IX and VEGF between intestinal- and diffuse-type adenocarcinomas may possibly explain the different clinical behavior of these tumors. CA IX expression, rather than VEGF positivity in tumors, enables the identification of a subpopulation, characterized by a more aggressive behavior and a poorer prognosis.

Risk factors for liver metastases after curative surgical procedures for gastric cancer: a prospective study of 208 patients treated with surgical resection

BACKGROUND

The aim of this study was to evaluate the risk of liver metastases after radical surgical treatment for gastric cancer, the potential risk factors involved, and the sensitivity of serum tumor markers during followup.

STUDY DESIGN

A total of 208 patients who had undergone curative resection for primary gastric cancer and a prospective followup protocol were studied. The association between clinicopathologic variables and hepatic recurrence was investigated using standard univariate methods and multivariate Cox regression analysis.

RESULTS

Mean followup time (+/- SD) for the entire patient population was 51 +/- 38 months (median 52 months) and was 88 +/- 24 months (median 81 months) for disease-free patients. Recurrence of gastric cancer was documented in 109 of 208 patients (52.4%). Liver metastases were found in 28 of 208 patients (13.5%); in most of these patients (82.1%) diagnosis was made within 2 years after surgical treatment. The estimated cumulative risk of liver metastases after 5 years was 16.4%. Cox regression analysis identified lymph node involvement (adjusted relative risk [RR] = 6.28, 95% confidence interval [CI] = 2.11 to 18.70, p = 0.001), preoperative positivity for CEA, CA 19-9, or CA 72-4 (RR = 5.18, 95% CI = 1.75 to 15.37, p = 0.003), and intestinal histotype (RR = 3.08, 95% CI = 1.06 to 8.96, p = 0.039) as independent predictors of hepatic recurrence. In 27 of 28 cases hepatic recurrence was associated with an increase in CEA, CA 19-9, or CA 72-4 serum levels above the cutoff, either before or at the time of the clinical diagnosis (sensitivity 96.4%).

CONCLUSIONS

Preoperative positivity for serum tumor markers, lymph node involvement, and intestinal histotype are risk factors for liver metastases after radical surgical treatment for gastric cancer. Postoperative measurement of serum tumor markers may be useful for an early diagnosis of hepatic recurrence during followup.

Prospective study of peritoneal recurrence after curative surgery for gastric cancer

BACKGROUND

Peritoneal carcinomatosis is a common cause of failure after surgery for gastric cancer. The present longitudinal study was designed to evaluate the incidence and potential predictors of peritoneal recurrence after curative resection for gastric cancer.

METHODS

Four hundred and forty-one patients who underwent potentially curative resections for gastric cancer in three surgical centres between 1988 and 1996 were evaluated. All patients were followed using a standard protocol following discharge from hospital. The correlation between tumour recurrence and clinicopathological variables was studied by univariate and multivariate analyses.

RESULTS

Gastric cancer recurred in 215 (49 per cent) of 441 patients. Peritoneal recurrence was observed in 77 patients (17 per cent), locoregional recurrence in 96 patients and haematogenous recurrence in 75. Multivariate logistic regression analysis of factors associated with peritoneal recurrence identified diffuse-mixed histological type (relative risk (RR) 4.31, P < 0.001), infiltration of the serosa (RR 3.36, P = 0.001), lymph node involvement (RR 2.67, P = 0.023) and tumour size (RR 1.11, P = 0.050) as significant independent variables. In the diffuse-mixed histological subtype, the 5-year cumulative risk of peritoneal recurrence was 12 per cent in the absence of serosal invasion, and 69 per cent in patients with infiltration of the serosa; in the intestinal subtype, the cumulative risk in patients with serosa-negative and -positive tumours was 4 and 21 per cent respectively.

CONCLUSION

Radical surgery offers a low probability of cure in patients with diffuse-mixed type of gastric cancer and involvement of the serosa, due to a high risk of peritoneal recurrence. These patients might benefit from adjuvant therapies to prevent peritoneal carcinomatosis.

The prognostic significance of preoperative serum CA 19-9 in patients with resectable gastric carcinoma: comparison with CEA

BACKGROUND AND OBJECTIVES

In this study, the prognostic value of pre-operative serum levels of tumor markers CA 19-9 and carcinoembryonic antigen (CEA) in gastric carcinoma which has been a controversial matter was investigated.

METHODS

Preoperative serum CA 19-9 (cut-off value 37 U/ml) and CEA (cut-off value 5 ng/ml) levels were measured in 168 patients with resectable gastric carcinoma. The correlation between tumor marker levels and clinicopathological features and overall survival was studied.

RESULTS

CA 19-9 and CEA positivity rates were 31.5 and 17.8% respectively. In CA 19-9 positive patients, the ratio of males, tumors exceeding subserosa and advanced stage tumors (stages III and IV) was significantly higher (P = 0.052, P = 0.0005 and P= 0.029, respectively). A weak correlation was found with CA 19-9 positivity and tumor location; however, no correlation existed between CA 19-9 positivity and age, tumor size, histologic type, lymph node, hepatic and peritoneal metastasis. The proportion of tumors extending beyond subserosa and with lymph node metastasis was significantly higher in CEA positive patients (P = 0.011 and P = 0.045, respectively). No correlation was found between CEA positivity and gender, age, tumor location, tumor size, and hepatic and peritoneal metastasis; however, a weak correlation existed between CEA positivity and histologic type and tumor stage. Overall survival was significantly poorer in CA 19-9 and CEA positive patients (log-rank test, P = 0.014, P = 0.003, respectively). However, the Cox proportional hazards regression analysis did not show independent prognostic value for both tumor markers.

CONCLUSIONS

In resectable gastric carcinoma, preoperative serum CA 19-9 and CEA levels may indicate stage of the disease, but neither has an independent prognostic value.

Clinical importance of preoperative carcinoembryonic antigen and carbohydrate antigen 19-9 levels in gastric cancer

Although serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 are commonly measured before surgery for gastric carcinoma, this clinical significance is not fully understood. We evaluated a total of 549 patients with gastric cancer who underwent gastrectomy. Levels of CEA and CA19-9 were measured preoperatively in all patients. We retrospectively analyzed correlations between CEA or CA19-9 and clinicopathologic features, and estimated the prognostic utility of the tumor markers by analyzing clinicopathologic characteristics of the carcinoma as a function of seropositivity or negativity of the antigens in combination or by raising the levels. The positivity rates of CEA (> or =5 ng/mL) and CA19-9 (> or =37 U/mL) were 19.5% and 18%, respectively. Serum CEA and CA19-9 positivity significantly correlated with depth of invasion, hepatic metastasis, and curativity. Forty-nine patients positive for both CEA and CA19-9 had significantly higher frequencies of lymph node metastasis, deeper invasion by the tumor, lower rates of curative resection (p < 0.01), and higher rates of hepatic metastasis (p < 0.05) than 377 patients with normal levels of CEA and CA19-9. Surgical outcomes of patients who were CEA- and CA19-9-positive were poorer than those of patients with normal CEA and CA19-9 levels (p < 0.01). Significant correlation was found between serum CEA and CA19-9 level (p < 0.001, r = 0.24). Doubling the threshold level of serum positivity to 10 ng/mL (CEA) and 74 U/mL (CA19-9) improved the prognostic value of these factors. However, multivariate analysis using Cox's hazards model revealed that only CEA positivity using the doubled threshold value (10 ng/mL) (p = 0.04, hazard ratio = 1.7), nodal involvement (p = 0.01, hazard ratio = 1.9), and depth of invasion (p = 0.02 hazard ratio = 1.5) significantly predicted prognosis. Carcinoembryonic antigen positivity using the doubled threshold level (10 ng/mL) was an important prognostic factor in patients with gastric cancer.

Clinicopathologic significance of sialyl Le(x) expression in advanced gastric carcinoma

Sialyl Lewis(x)antigen (SLX) is a carbohydrate antigen that serves as a ligand for selectin, an adhesion molecule expressed on vascular endothelial cells. The expression of SLX in 245 patients with advanced gastric carcinoma was examined immunohistochemically, and its clinicopathologic significance was analysed. We classified the patients with advanced gastric carcinoma into 91 with differentiated type and 154 with undifferentiated type. SLX expressed in 135 of 245 patients (55%), comprising 68 (75%) patients with differentiated carcinoma and 67 (44%) with undifferentiated carcinoma. The positive rate for SLX expression was significantly higher among patients with differentiated carcinoma than among those in undifferentiated carcinoma (P<0.0001). With differentiated carcinoma, the incidence of lymph node metastasis, advanced tumour stage (stage III and IV) and liver recurrence was significantly higher in SLX-positive patients than in SLX-negative ones (P<0.0001, P = 0.0065 and P = 0. 028, respectively). Moreover, the prognoses were better in patients with SLX-negative tumours than in those with SLX-positive tumours (P = 0.019). With undifferentiated carcinoma, there were no significant correlations between SLX expression and any clinicopathological features or prognoses. The clinicopathologic significance of SLX expression in gastric carcinoma patients depends on histologic type. SLX expression may be of great relevance in predicting liver metastases in patients with differentiated carcinoma.

Genetic pattern, histological structure, and cellular phenotype in early and advanced gastric cancers: evidence for structure-related genetic subsets and for loss of glandular structure during progression of some tumors

Gastric cancer shows remarkable heterogeneity in histological pattern, cellular phenotype, and genotype. Tumor subsets identified by varying procedures have shown limited reciprocal correlation and have failed to provide a sound rationale for the characterization and classification of all tumors. Based on a case series of 130 gastric cancers that covered both early (70 cases) and advanced (60 cases) stages and that represented most histological types and structural patterns, this study investigated (1) microsatellite instability and p53 gene mutation by means of PCR-based molecular techniques and (2) p53 protein accumulation or tumor cell immunophenotype by means of immunoperoxidase procedures. It was found that microsatellite instability and p53 gene mutation involve two distinct subsets of both early and advanced-stage glandular (intestinal) cancer, and that, contrastingly, they leave purely diffuse cancers unaffected. Mixed cancers, namely, those in which glandular admixed with diffuse growths, showed scarce microsatellite instability at all stages, whereas prominent p53 gene mutation and p53 protein accumulation was limited to the advanced stage alone. No significant correlation was found between tumor cell immunophenotype and either genotype or histotype, although some correlation with particular structural patterns was detected. Comparison of intramucosal with invasive growths within any given tumor suggested that invasive cancers with diffuse-type growth arise in part from mucosal cancers of glandular or mixed structure through progressive loss of intercellular junctional systems. It is concluded that at least two genetically distinct subsets of glandular cancer, one with microsatellite instability and the other with p53 lesions, should be separated both from purely diffuse cancer and, at least in the advanced stage, from mixed cancer. Available evidence suggests distinct clinicopathologic profiles for such tumor entities.

Distinct clinicopathologic characteristics of diffuse- and intestinal-type gastric cancer in Taiwan

The clinicopathologic features of 221 patients with intestinal-type (IT) gastric cancer were compared retrospectively with those of 290 diffuse type (DT). Intestinal type was characterized by an older mean age (65.0 +/- 10.8 years vs. 56.2 +/- 13 years), a higher male-female ratio (2.56 vs. 1.06), predominance of blood group O (46.2% vs. 31.1%), and frequent habitual smoking (50.7% vs. 31.4%) and drinking (28.5% vs. 17.6%) than did DT. In contrast, DT had a higher frequency of positive history of parent or sibling with gastric cancer (9.3% vs. 4.1%) and blood group A (40.3% vs. 27.6%) than did IT. The distinguishing histologic features of DT included more Borrmann type IV (13.1% vs. 1.3%) but less Borrmann type I (1% vs. 7.2%), more frequent involvement of middle third (26.9% vs. 15.9%) and whole stomach (4.1% vs. 0%), and more peritoneal seeding (15.5% vs. 9%), lymph node metastasis (67.2% vs. 51%), and nerve permeation (34.1% vs. 24.4%), but less Helicobacter pylori infection (55.9% vs. 69.2%) when compared with those of IT. There was no difference in depth of tumor invasion, venous permeation, duodenal involvement, and postoperative survival between IT and DT. These distinct clinicopathologic features between IT and DT in Taiwan suggest the presence of a different pathogenic process for these two histologic subtypes of gastric cancer.

Reduced expression of the CXC chemokine hIRH/SDF-1alpha mRNA in hepatoma and digestive tract cancer

We isolated human intercrine reduced in hepatomas (hIRH) as a mRNA whose expression was reduced in differential displays from human hepatocellular carcinoma. hIRH is equivalent to the alpha-chemokine SDF-1alpha/PBSF. We have previously demonstrated on Northern blot analysis that although hIRH mRNA expression is common in human normal tissues, it is absent from pre-malignant colonic adenomas and from 27 human malignant cell lines. However, there are no reports on the mRNA status of hIRH in other human cancers. The present study was designed to investigate semi-quantitatively the expression of hIRH/SDF-1alpha mRNA in hepatocellular carcinoma and digestive tract cancers by reverse transcription-polymerase chain reaction (RT-PCR). The expression of hIRH/SDF-1alpha in the majority of cancer tissues analyzed was markedly reduced compared with that in adjacent non-cancer tissue. RT-PCR was more sensitive than Northern blots in the detection of hIRH mRNA. The average (mean +/- SE) tumor/normal (T/N) ratio determined by RT-PCR was 0.40 +/- 0.07 in 10 pairs of hepatoma, 0.38 +/- 0.09 in 14 pairs of colon cancers, 0.43 +/- 0.07 in 10 pairs of esophageal cancers and 0.70 +/- 0.09 in 26 pairs of gastric cancers. As a control, the mean G3PDH T/N ratio was 1.16 +/- 0.06. The distribution of T/N ratios was significantly different between gastric cancer and the other cancers, but there was no correlation between hIRH/SDF-1alpha expression and clinicopathological characteristics in gastric cancer. Our findings demonstrate that hIRH/SDF-1alpha expression is reduced in the majority of gastrointestinal tumors.

Matrix metalloproteinase-7 expression in gastric carcinoma

BACKGROUND/AIMS

Matrix metalloproteinase-7 (MMP-7) belongs to the same family as matrix degrading metalloproteinase (MMPs) that may play an important part in cancer cell invasion and metastasis. This study reports on the MMP-7 mRNA expression level both in human gastric carcinomas and the normal gastric mucosa.

METHODS

From fresh specimens of 47 surgical pairs of primary gastric carcinomas and corresponding normal tissue specimens, cDNA was obtained by reverse transcription (RT) and thereafter MMP-7 mRNAs were detected by means of a polymerase chain reaction. The tumour/normal (T/N) ratio of MMP-7 expression was calculated after correcting for glyceraldehyde-3-phosphate dehydrogenase as an internal control.

RESULTS

The expression corrected levels of MMP-7 mRNA of the tumour was greater than that of the normal mucosa in 41 of 47 cases (87%). The 13 cases whose T/N ratio was more than 2.1 showed a deeper invasion of the gastric wall, and more frequent lymphatic or vascular permeations than the 34 cases whose T/N ratio was less than 2.0. An immunohistochemical study showed that MMP-7 was predominantly expressed in the cancer cells, weakly expressed in normal epithelial cells, and not expressed in the surrounding stromal cells.

CONCLUSIONS

These findings suggest that the overexpression of MMP-7 may thus play an important part in tumour invasion in gastric carcinomas while, in addition, MMP-7 may also prove to be a useful marker for determining the biological aggressiveness of gastric carcinoma.

Expression of ornithine decarboxylase mRNA in gastric carcinoma

BACKGROUND

Ornithine decarboxylase (ODC) is a key rate-limiting enzyme in polyamine biosynthesis. Several studies using an enzyme assay revealed that the ODC activity was higher in tumor tissue than in normal tissue. However, there is little information on the mRNA status of ODC in surgical specimens. ODC is a transcriptional target gene of c-myc.

METHODS

cDNA was obtained by reverse transcription (RT) from fresh specimens of 56 surgical pairs of primary gastric carcinomas and corresponding normal tissue specimens. The ODC and c-myc mRNAs were subsequently detected by means of the polymerase chain reaction. The tumor/normal (T/N) ratio of ODC expression was calculated after correcting for glyceraldehyde-3-phosphate dehydrogenase as an internal control. The T/N ratio of ODC was plotted against that of c-myc.

RESULTS

The corrected expression levels of ODC mRNA in the tumor were greater than those of the normal mucosa in 36 of 56 cases (64%). The cases of tumor with vascular vessel invasion showed a higher T/N ratio than those without vascular invasion (P < 0.01). Similarly, female patients showed a higher T/N ratio than male patients (P < 0.01). There was a significant correlation between the expressions of both ODC and c-myc genes (P < 0.05).

CONCLUSIONS

The findings imply that (1) overexpression of ODC mRNA in tumor tissue may correlate with aggressive biologic behavior, such as vascular vessel invasion, and (2) there is an intimate correlation between ODC and c-myc genes.