The value of flow cytometric analysis in patients with gastric cancer

Prognostic value of DNA aneuploidy in gastric cancer: a meta-analysis of 3449 cases

Background

DNA aneuploidy has attracted growing interest in clinical practice. Nevertheless, its prognostic value in gastric cancer patients remains controversial. This meta-analysis aims to explore the impact of DNA ploidy status on the survival of gastric cancer patients.

Methods

We used PubMed and Web of Science databases to retrieve relevant articles. The correlation between DNA aneuploidy and the clinicopathological features of gastric cancer, such as stage, depth of invasion (T), lymph node metastasis (N), distant metastasis (M), differentiation (G), tumor types (Lauren classification) and overall survival (OS) were evaluated. Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were collected carefully from each article OS was presented with HRs. The relationships between DNA aneuploidy and each characteristic were analyzed using risk ratios (RR) and a 95% confidence interval (CI). Significance was established using P < 0.05. Funnel plot was conducted to detect the publication bias.

Results

After careful selection, 25 studies involving 3449 cases were eligible for further analyses. Patients with DNA aneuploidy were considered at risk of more advanced stages (stage III-IV vs. stages I-II, RR = 1.23; 95% CI, 1.07 to 1.42; P = 0.003), lymph node metastasis (N+ vs. N-: RR = 1.43; 95% CI, 1.12 to 1.82, P = 0.004), and intestinal tumor type (intestinal vs. diffuse: RR = 1.45; 95% CI, 1.02 to 2.06; P = 0.04). And an adverse relation was observed between DNA aneuploidy and tumor differentiation. While no association was found between DNA aneuploidy and distant metastasis (P = 0.42) nor depth of tumor invasion (P = 0.86). Regarding overall survival, aneuploid tumors were associated with worse survival in all patients (P < 0.00001).

Conclusions

We found that DNA aneuploidy was an important predictor for gastric cancer patients, and should be used as a potential biomarker for further classification in gastric cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5869-9) contains supplementary material, which is available to authorized users.

Timing of death from tumor recurrence after curative gastrectomy for gastric cancer

In Western literature, there are few studies investigating the predictors of early versus late recurrence after curative gastrectomy for gastric cancer. The current study analyzed (1) patients who died of recurrent gastric cancer and (2) prognostic factors, which can be applied to timing of death from tumor recurrence. Of 492 patients who underwent curative resection (R0) for gastric cancer in the Department of Surgery, Medical Faculty of Istanbul between 1994 and 2000, 142 patients who died of recurrence were included into study. None of the patients had received postoperative adjuvant treatment. The patients were divided into 2 groups: an early recurrence group that included 102 patients who recurred and died within 2 years after surgery, and a late recurrence group, which included 40 patients who died of recurrence more than 2 years after surgery. Clinicopathologic findings were compared between the early and late recurrence groups. Multivariate analysis was performed to investigate the independent factors, which are predictive for early versus late recurrence, and prognostic factors independently associated with the survival period. In multivariate analysis, the early recurrence group, when compared with the late recurrence group, was characterized by lymph node metastasis (N1-3 versus N0; P = 0.002). Overall survival was influenced by nodal status (N1-3 versus N0; P = 0.003), type of operation performed (radical total versus radical subtotal gastrectomy; P = 0.003), Eastern Cooperative Oncology Group performance status (PS 3-4 versus PS 1-2; P = 0.004), and tumor localization (cardia versus corpus and antrum; P = 0.046). In contrast, T stage of the disease was not prognostic for survival, although it was close to statistical significance (P = 0.066). Multivariate analysis showed that poorer performance status at initial presentation (P = 0.001) and lymph node metastasis (P = 0.032) independently correlated with overall survival (P = 0.002). Lymph node status was the most important factor predictive for early versus late recurrence and patients with lymph node metastases were at more risk of death within 2 years after curative operation for gastric cancer. Postoperative chemoradiotherapy should be especially recommended for patients at high risk of recurrence of adenocarcinoma of the stomach or who have undergone curative resection.

DNA aneuploidy and high proliferative activity but not K-ras-2 mutations as independent predictors of clinical outcome in operable gastric carcinoma: results of a 5-year Gruppo Oncologico dell'Italia Meridonale (GDIM) prospective study

BACKGROUND

The prognostic value of DNA ploidy, S-phase fraction (SPF) and K-ras-2 mutations in gastric carcinoma (GC) has not yet been clearly defined. The aim of this study was to clarify the association between biomolecular variables, tumor characteristics, and clinical outcome in GC patients.

METHODS

Resected specimens from a consecutive series of 69 patients with GC who underwent potentially curative surgery were studied prospectively. DNA ploidy and SPF were assessed by flow cytometry on multiple frozen tumor samples, whereas K-ras-2 mutations were detected by polymerase chain reaction followed by single-strand conformation polymorphism. All the patients involved in this study were followed up for a mean of 95 months.

RESULTS

DNA aneuploidy was present in 72% of the cases (50 of 69), whereas 10% of these (5 out of 50) showed multiclonality. Mutations of K-ras-2 were detected in 8% of the tumors (5 of 63). Both DNA ploidy and SPF were associated with TNM stage (American Joint Committee on Cancer [AJCC] staging system) and node status. Moreover, DNA aneuploidy was significantly related to high SPF. K-ras-2 mutations were not associated with clinicopathologic variables or flow cytometric indicators. At univariate analysis, advanced TNM stage, node involvement, diffuse histotype, depth of invasion, DNA aneuploidy, and high SPF proved to be significantly related to quicker tumor relapse and to shorter overall patient survival. With multivariate analysis, DNA aneuploidy, high SPF, and depth of invasion were related to risk of tumor relapse and patient death, whereas diffuse histotype was independently related to patient risk of tumor relapse.

CONCLUSIONS

DNA ploidy and SPF, when associated with clinicopathologic staging, might be useful for the identification of GC patients who have different risks for death or relapse of disease.

p53 abnormalities in adenocarcinoma of the gastric cardia and antrum

AIM

To compare the frequency and type of p53 alterations (gene mutation and/or protein overexpression) in a consecutive series of surgically resected adenocarcinomas arising in the gastric cardia and gastric antrum, and to evaluate associations with clinicopathological findings (age, sex, and tumour histology, grade, and stage).

METHODS

The series comprised 50 patients with adenocarcinoma of the cardia and 20 patients with adenocarcinoma of the antrum. p53 gene mutations (exons 5-8) were detected by denaturing gradient gel analysis and DNA sequencing. Nuclear p53 overexpression was detected by immunohistochemistry with the DO7 antibody.

RESULTS

p53 gene mutations were found in 21 of 50 and five of 20 adenocarcinomas of the cardia and the antrum, respectively. Base transitions occurring at CpG dinucleotides were frequent in both types of tumour. p53 protein overexpression was seen in 32 of 50 and seven of 20 adenocarcinomas of the cardia and of the antrum, respectively. p53 gene mutation and/or protein overexpression were significantly more frequent in adenocarcinomas of the cardia (37 of 50) than in adenocarcinomas of the antrum (seven of 20). There were no differences in the clinicopathological characteristics of the tumours between p53 positive and p53 negative cases in both types of cancer.

CONCLUSIONS

This study shows that p53 alterations are more frequent in adenocarcinoma of the cardia than in adenocarcinoma of the antrum. This feature is consistent with the clinical and epidemiological characteristics of these cancers, which suggest that adenocarcinoma arising in the gastric cardia might be related to oesophageal adenocarcinoma, and unrelated to adenocarcinomas of the gastric body and antrum.

Prognostic value of DNA flow cytometry in stomach cancer: a 5-year prospective study

The role of DNA flow cytometry in the prediction of prognosis for patients with stomach cancer remains to be defined. Thus we studied prospectively the role of DNA flow cytometry as a prognosis indicator in stomach cancer patients in a high-incidence area. Between November 1990 and December 1992, primary stomach cancer tissues were obtained from the surgical specimens from 217 patients (148 male, 69 female). DNA flow cytometric analyses of DNA ploidy and S-phase fraction were performed and the results were correlated with patient survival. The median age of the patients was 55 years (range 24-78). Aneuploid cell population was found in 114 of 217 samples (53%). Tumour S-phase fraction was obtained in 96 of 103 diploid tumours (93%) and 61 of 114 aneuploid tumours (54%). After median follow-up of 66.1 months, the patients with tumours with an S-phase fraction over 17% had significantly worse survival rates than patients with tumours with S-phase fractions of lower than 8% or 8-17% (45% vs 59% and 63% of patients surviving, P = 0.007). Tumour ploidy status did not correlate with patient survival. Multivariate analyses showed that the TNM stage remained the most important prognostic indicator. The tumour S-phase fraction was also an independent prognostic indicator (relative risk 2.300, 95% CI, 1.252-4.223). Tumour S-phase fraction obtained by DNA flow cytometry is an independent prognostic indicator for the survival of the patients with stomach cancer.

Early gastric carcinoma with focal advanced cancer: a particular subtype of gastric carcinoma

Early gastric cancer (EGC) is defined as a carcinoma limited to the mucosa or mucosa and submucosa, irrespective of whether metastasis to lymph nodes has occurred. EGC presents a much more favorable prognosis than advanced gastric carcinoma (AGC), with a 5-year survival rate between 88% and 96% for EGC versus 45% to 50% for AGC. Moreover, some gastric cancers appear as a more or less extended EGC with focal AGC (fAGC). The purpose of this study was to analyze prognostic factors in this intermediate group of tumors. From 1981 to 1992, among the 615 gastrectomy specimens with carcinoma examined at the Institute of Pathology of the University of Lausanne, only 19 tumors corresponded to the criteria of EGC with fAGC. Clinicopathologic features were studied, and a cytophotometric DNA analysis was performed. Our results show a 5-year survival rate for EGC with fAGC of 61% (11 of 18 patients alive), intermediate between that of EGC and AGC. No significant correlations were found between the most known predictive factors and prognosis. Most tumors analyzed (16 of 19) showed a diploid DNA content in the superficial as well as in the invasive areas. Contrary to the findings in the literature, which show a high-ploidy DNA pattern in most AGC, our cases show low-ploidy DNA even in the invasive portion of the tumors. In conclusion, we show that EGC with focal AGC represents a gastric cancer with an intermediate prognosis and, therefore, must be considered as a specific subtype of gastric carcinoma.

Comparison of p53 and DNA content abnormalities in adenocarcinoma of the oesophagus and gastric cardia

This study examined the association between 17p allelic loss, p53 gene mutation, p53 protein expression and DNA aneuploidy in a series of adenocarcinomas arising in the oesophagus and gastric cardia. 17p allelic loss was detected in 79% (15 of 19) of oesophageal and in 83% (29 of 35) of gastric adenocarcinomas. p53 mutations were detected in 70% (14 of 20) and 63% (26 of 41) of oesophageal and of gastric adenocarcinomas respectively. Both tumour types were associated with a predominance of base transitions at CpG dinucleotides. In five cases of oesophageal adenocarcinoma, the same mutation was detected both in tumour and in adjacent dysplastic Barrett's epithelium. Diffuse p53 protein expression was detected in 65% (13 of 20) and 59% (24 of 41) of oesophageal and of gastric tumours, respectively, and was associated with the presence of p53 missense mutation (Chi-squared, P < 0.0001). DNA aneuploidy was detected in 80% (16 of 20) of oesophageal and in 70% (28 of 40) of gastric tumours. No association was found between p53 or DNA content abnormalities and tumour stage or histological subtype. In conclusion, this study detected a similar pattern of p53 alterations in adenocarcinoma of the oesophagus and gastric cardia--molecular data consistent with the observation that these tumours demonstrate similar clinical and epidemiological features.

DNA flow cytometry in gastric carcinoma: implication in patients with potentially curative resection

BACKGROUND AND OBJECTIVES

The relevance of DNA ploidy as a prognostic factor in patients with gastric cancer is controversial. The prognostic significance of DNA ploidy and its relationship to conventional histological grading and staging of the tumor (TNM stage, Lauren, Ming and WHO classification) were evaluated.

METHODS

DNA ploidy of the tumor was determined by flow cytometry on archival material from 76 patients who underwent R0, D2 stomach resection.

RESULTS

DNA aneuploidy was found in 39 cases (51%). No significant association between DNA aneuploidy and either patients' sex, pT, pN, type according to Ming or Borrmann and tumor localization was found. The incidence of DNA aneuploidy was significantly lower in tumors of diffuse type according to Lauren, in signet-ring cell or undifferentiated type (WHO), in grade 3/4 tumors, and in patients younger than 50 years. We found no significant difference in survival of patients with DNA aneuploid when compared to DNA diploid tumors, although the prognosis of the patients with lower DNA index (DI < 1.2) tended to be better than that of higher DNA index (DI > 1.2).

CONCLUSIONS

DNA ploidy appears to be of limited prognostic value after R0, D2 resection of stomach cancer.

DNA aneuploidy in gastric carcinoma. Flow cytometric data related to survival, location, and histopathologic findings

BACKGROUND

The aim of the study was to evaluate the prognostic significance of DNA ploidy of gastric carcinomas.

METHODS

The DNA content was analyzed by flow cytometry on archival paraffin-embedded material from tumors of 97 consecutive patients.

RESULTS

A multivariate analysis showed that the DNA ploidy pattern and lymph node metastasis were the only independent prognostic markers for survival (p = 0.01 and p = 0.02, respectively). The relative risk of death due to gastric cancer was three times greater for patients with DNA hypertetraploid tumors than for patients with DNA diploid tumors and twice as high for patients with lymph node metastasis as for patients without. Well and moderately differentiated carcinomas were more frequently aneuploid than tumors with poor differentiation (p = 0.047). There was no correlation between tumor ploidy pattern and location. In univariate analysis tumor growth through the serosal wall was predictive of poor survival (p = 0.003).

CONCLUSIONS

DNA ploidy is an independent prognostic indicator for cancer-specific survival in gastric cancer.