Correlation of DNA ploidy and clinical outcome in Borrmann type 4 gastric carcinoma

Early gastric cancer in the young: clinicopathological study

BACKGROUND

Thirty-four cases of early gastric carcinoma in patients under 50 years of age treated in the period from 1985 to 1995 were reviewed.

METHODS

These constituted 3.7% of 923 cases of gastric cancer in patients of all ages that were treated at Sendai National Hospital during the same 10-year period. Data were compared with those of 194 patients 50 years of age or older.

RESULTS

The incidence of gastric cancer in men and women was almost the same in both groups. Tumours tended to be located distally in the stomach. Macroscopically, depressed lesions were more common in younger patients. Significant differences were observed in depth of invasion, histological type and histological growth patterns.

CONCLUSIONS

The distinctive histological features of early gastric cancer in younger patients were a diffuse type of cancer with infiltrative tumours in the mucosal layer. The prognosis of younger patients was similar to that of older patients.

E-cadherin and urokinase-type plasminogen activator tissue status in gastric carcinoma

BACKGROUND

E-cadherin (ECD) is known to be an invasion suppressor gene, and urokinase-type plasminogen activator (uPA) plays a central role in infiltration of solid cancers.

METHODS

To elucidate the relationship between expression of these factors and metastasis in patients with gastric cancer, the authors examined immunohistochemically a combination analysis of uPA and E-cadherin expression in 98 primary tumors, and the results were correlated with several parameters related to metastasis.

RESULTS

Among 125 tumors, 42 (34%) were evaluated as having E-cadherin expression (E-cadherin-positive), and the other 83 (66%) were defined as having reduced E-cadherin expression (E-cadherin-negative). uPA immunoreactivity was observed in 82 tumors (66%). There were four subtypes of patterns of uPA and E-cadherin expression: 22 uPA-negative/E-cadherin-positive, 17 uPA-negative/E-cadherin-negative, 21 uPA-positive/E-cadherin-positive, and 65 uPA-positive/E-cadherin-negative, uPA overexpression and reduced E-cadherin expression were associated with lymph node metastasis, vessel invasion, serosal involvement, and poor prognosis. In addition, uPA-positive/E-cadherin-negative tumors were associated significantly with large tumors, positive serosal invasion, lymph node involvement, and poor prognosis. Patients with uPA-positive/E-cadherin-negative expression had the poorest prognoses, compared with the three other groups of patients uPA-positive/E-cadherin-negative tumors had a fourfold relative risk of death when compared with uPA-negative/E-cadherin-positive tumors. A Cox proportional hazard model projected lymph node status as the strongest of the prognostic variables followed by DNA ploidy patterns and uPA/E-cadherin tissue status.

CONCLUSIONS

These results indicate that immunohistochemical combination analysis of uPA and E-cadherin expression may be a powerful aid in evaluating metastatic potential or the prognosis of patients with gastric cancer.

Cytophotometric study of nuclear DNA content in scirrhous gastric carcinoma

We made a cytophotometric DNA analysis using 21 scirrhous gastric carcinomas (SGC), and compared the results with those of 12 undifferentiated type early gastric carcinomas (EGC) located in the gastric body. Nuclear DNA content of tumor cells was measured in the mucosa of SGC (SGCm), serosa of SGC (SGCs) and mucosa of EGC (EGCm). DNA distribution pattern was high ploid in 18 SGCm (86%), 16 SGCs (71%) and 4 EGCm (33%). Mean DNA content was 4.02c in SGCm, 3.91c in SGCs and 3.26c in EGCm. Percentage of tumor cells with a DNA content over 3c was 77.4% in SGCm, 69.1% in SGCs and 49.5% in EGCm. Statistically significant differences in these 3 factors were present between SGCm and EGCm, but absent between SGCm and SGCs. Furthermore, DNA distribution pattern was not different between the mucosa and serosa in 19 SGC (90%). The results suggest that most scirrhous gastric carcinomas are high ploid in origin and do not change their biologic behaviour throughout the tumor progression.

Understanding the biology of cancer: has this any impact on treatment?

Rapid advances in laboratory techniques in the last two decades and, what is more important, in the last 5-7 years have significantly increased our knowledge and understanding on many fronts. We have learned much about (a) the basic biological processes of growth control and its aberrations, (b) the possible mechanisms involved in genetic initiation, progression and suppression, (c) the complexity of the multistep carcinogenesis induced by viruses, chemicals, hormones and other iatrogenic factors, (d) the secrets of immunological defence mechanisms and a host of other fundamental processes, (e) the application of molecular biology techniques to clinical problems, etc. The list is unending and often leads the uninitiated clinician to believe that the resolution of the mystery of the cancer cell and its successful control and cure are almost at hand. He or she often comes to believe that conventional principles in cancer treatment have radically changed from the 1960 and 1970 and that a new era in cancer treatment, based on our recent biological understanding, has already arrived. There is little doubt that the treatment scenario has changed significantly and that there is more hope for a cancer patient today than ever before-especially in certain types of paediatric and lymphoproliferative disorders; however, the unfortunate fact is that this cautiously optimistic therapeutic scenario has come about not because of any great understanding of the biological processes, which continue to confound us, but because of the intense interaction of various therapeutic disciplines and sophisticated technology now available for early diagnosis and more efficient therapeutic procedures in radiotherapy, chemotherapy and surgery. The author presents evidence and data here to show that, while treatment results have improved, we have a long way to go in understanding the biological processes before our knowledge can have a significant impact on the overall treatment methods in current use. The principles of cancer treatment, though modified have not changed. In fact, in the light of our current knowledge, they have been re-emphasized.

Resection margin in patients with gastric cancer associated with esophageal invasion: clinicopathological study

We investigated the correlations between resection margin involvement by carcinoma and a number of clinicopathological features in patients with gastric cancer and esophageal invasion. From January 1968 to December 1988, 1,040 patients with carcinoma of the stomach underwent gastric resection. Thirty-nine patients had tumor infiltration of the esophagus on histological examination of the resected specimens. The patients were divided into two groups on microscopic examination: those in whom the resection margin was less than 5 mm wide, and those in whom it exceeded 5 mm microscopically. There were 6 and 33 patients in the narrow and wide margin groups, respectively. There were statistically significant differences in tumor size, depth of cancer invasion, and macroscopic appearance between the two groups. The risk of resection margin involvement was high in tumors with the following features: large Borrmann type 4 tumor (macroscopic appearance and size) and infiltrative carcinoma (depth of invasion).

Heterogeneity in gastric carcinoma with special reference to DNA content and mitotic activity: histopathologic differentiation

DNA ploidy and mitotic activity were microspectrophotometrically investigated in 46 patients with gastric carcinoma. Measurements of DNA content and mitotic index (M.I.) were examined in the mucosal, submucosal, muscularis propria, and serosal layers of tumors, respectively. The frequency of cells with values exceeding hexaploid chromosome (6c) and mitotic counting analysis revealed a significant higher value in serosa, compared with findings in the mucosa. This tendency was not evident in cases of a differentiated type adenocarcinoma but was noted in those with the undifferentiated type. There were 37 tumors (80.0%) with the same DNA distribution patterns in every layer of the stomach (homogeneous DNA ploidy). Heterogeneity of DNA ploidy was observed in nine tumors (20.0%). Carcinoma with a heterogeneous DNA ploidy manifested a significantly higher incidence of metastasis to the lymph nodes than did those with homogeneous type. Characteristically, there was venous permeation preponderance in the differentiated type and peritoneal dissemination preponderance in the undifferentiated type. This evidence of DNA heterogeneity in gastric carcinoma tissues suggests a possible correlation with the metastatic behavior.

DNA ploidy and cell-cycle analysis: tools for assessment of cancer prognosis

DNA ploidy and cell cycle analysis as measured by flow cytometry (FC) and image analysis (IA) have moved out of the realm of the research laboratory to become valid clinical tests used in the assessment of prognosis of the cancer patient. Although much information on the relationship of DNA ploidy/%S-phase analysis to patient prognosis is available in the literature, the data are not presented in such a way as to be helpful in clinical decision making. Because predictive values and confidence intervals, which measure the likelihood that a given clinical test will rule in or rule out a clinical outcome, were not calculated in previous reviews, conclusions about the clinical utility of these analyses were not possible. Using the available raw data on DNA ploidy and %S-phase analysis from previously published papers, predictive values and confidence limits were calculated for specific clinical presentations. In several such clinical situations (tumor type, stage, etc.), predictive value of greater than 90% was derived. We conclude that in these situations DNA ploidy and %S-phase analysis can be used to predict clinical outcome, to design treatment, and to guide patient management. The evaluation of the clinical utility of these tests must ultimately rest on prospective trials which show that randomized arms respond to treatment regimens dependent upon the DNA ploidy and %S-phase status.