Flow cytometric analysis of DNA heterogeneity in superficial carcinoma of the esophagus

Heterogeneity of DNA content in laryngeal squamous cell carcinoma in relation to histopathological variables

CONCLUSION

Multivariate analysis showed age, lymph node status, proliferative index in transformation border, and DNA index in the center of laryngeal squamous cell carcinoma to be significant predictors for survival. By accessing distinctive areas of the tumor we were able to reduce the impact of intratumoral heterogeneity on prognostic factors.

OBJECTIVES

Laryngeal carcinomas are characterized by considerable histological variation within the tumor. The possible effects of this morphological heterogeneity on the estimation of tumor DNA content were investigated.

MATERIALS AND METHODS

We analyzed 92 cases of archived, paraffin-embedded laryngeal carcinoma. For each tumor, three different regions, defined microscopically (center of tumor, transformation border, invasive border), were analyzed. DNA content was measured by flow cytometry. Three parameters were evaluated: DNA ploidy, DNA index, and proliferative index.

RESULTS

DNA ploidy, DNA index, and proliferative index were higher in the tumor center than in the respective borders. Intratumoral differences in DNA ploidy were observed in 56 tumors (60.8%); DNA index heterogeneity was observed in 57.6% cases. Proliferative index varied greatly in morphologically different parts of the same carcinoma. DNA ploidy and DNA index of the transformation border correlated with tumor size and lymph node status. Proliferative index of the tumor center and of transformation border correlated with lymph node status, tumor size, and histological grade.

Significance of matrix metalloproteinase 9 and CD34 expressions in esophageal carcinoma: correlation with DNA content

BACKGROUND

Esophageal carcinoma is common in many countries, and it is characterized by poor prognosis and rapid clinical progression with a high frequency of lymph node metastasis and recurrence. The present study was carried out to evaluate the correlation between vascular endothelial cell marker (CD34), matrix metalloproteinase type 9 (MMP9), and DNA content in esophageal carcinoma.

METHODS

A total of 38 patients were classified with histopathologic examination as 8 cases with adenocarcinoma, 24 cases with squamous cell carcinoma, and the last 6 cases with undifferentiated carcinoma. The obtained results of the patient group were compared with the results of 6 cases with proven normal esophageal mucosa as a control group. The samples of patients and controls were subjected to immunohistochemical evaluation of CD34 and MMP9 expression along with DNA index determination using flow cytometry.

RESULTS

There was a significant difference between patients and normal cases in DNA index, CD34, and MMP9 pattern (P = 0.003, <0.001, and 0.002, respectively). DNA index was positively correlated with MMP9 (r = 0.574, P < 0.001) and with CD34 (r = 0.562, P < 0.001). MMP9 was correlated with CD34 (r = 0.55, P < 0.001). A significant difference was found in both microvessel density and MMP9 expression with respect to tumor grade and stage. The microvessel density in patients with highly positive staining for MMP9 was higher than in those with negative and weak staining for MMP9 (P = 0.002).

CONCLUSION

The analysis of DNA content along with detection of CD34 and MMP9 in esophageal cancer can successfully differentiate the different pathologic lesions and hence can be used powerfully in disease prognosis reflecting valuable information about the aggressiveness and activity of those lesions.

Prognostic significance of biologic factors in squamous cell carcinoma of the esophagus

BACKGROUND

Esophageal carcinoma is one of the most lethal tumors. Therefore, it is important to identify prognostic factors for patients with this disease. The objective of this study was to clarify the relation between clinicopathologic and biologic factors in esophageal carcinoma and to determine the prognostic significance of different biologic factors.

METHODS

DNA ploidy pattern, Ki-67 labeling index (LI), and cyclin D1 and p53 protein expression were examined and detailed pathologic examinations were conducted on tumors from 53 patients (46 males and 7 females with a mean age of 66 years [range, 47-85 years]) with surgically resected esophageal squamous cell carcinoma and the prognostic value of these factors was evaluated.

RESULTS

Of the 53 esophagus carcinomas examined, 26 (49%) were classified as DNA diploid. The mean Ki-67 LI was 45 +/- 4. 9% (range, 10.5-86.1%). p53 expression was detected in 38 of the carcinomas (71.7%) and cyclin D1 expression was detected in 35 (66%). Various prognostic factors were examined using the Cox stepwise regression model, four of which were found to correlate with overall survival: tumor size (P = 0.0346), lymph node status (P = 0.0384), Ki-67 LI (P = 0.0161), and p53 expression (P = 0.001). Lower Ki-67 LI and a lower rate of p53 expression were detected in the long term survival group (> 3 years) compared with the short term survival group (P = 0.00045 and P = 0.0023, respectively).

CONCLUSIONS

The biologic factors of Ki-67 LI and p53 expression, as well as clinicopathologic factors, may be used as independent prognostic factors for patients with esophageal carcinoma. However, the results of the current study do not support cyclin D1 expression as a prognostic factor.

Intratumoral heterogeneity of DNA content in renal cell carcinoma and its prognostic significance

BACKGROUND

A multiple sampling study was performed on 124 specimens of renal cell carcinomas to analyze the consistency and reliability of DNA measurements. The authors investigated intratumoral DNA heterogeneity and its role as a adverse prognostic factor for disease progression.

METHODS

DNA content was analyzed by flow cytometry on three different samples of the same tumor. The Cronbach alpha coefficient was used to assess the reliability and a Cox proportional hazards model was used to test the effect of DNA ploidy heterogeneity on time of disease progression.

RESULTS

The agreement among the DNA ploidy samples was high. The number of aneuploid findings increased significantly with the number of samples analyzed. The presence of non-diploid cell populations was a significant adverse predictive value for disease progression. However, the authors were unable to demonstrate that intratumoral heterogeneity DNA content had any influence on the biological behavior of the tumor.

CONCLUSIONS

Determination of DNA ploidy based on single samples may be inaccurate. Spatial variation in DNA ploidy is a feature of renal cell carcinoma; however, its biologic significance remains to be demonstrated.

Representativity of incisional biopsies for the assessment of flow cytometric DNA content in head and neck squamous cell carcinoma

DNA flow cytometry studies of squamous cell carcinoma of the head and neck have shown that patients with diploid tumours have favourable prognoses, whereas the outcomes of those with DNA aneuploid tumours are poor. DNA flow cytometry is therefore increasingly used as an integral part of diagnostic procedures. To evaluate how representative biopsies predict the DNA ploidy of oral carcinomas, incisional biopsies taken pretherapeutically from 256 tumours were compared with the corresponding surgical resection specimens. Sixty-six tumours exclusively displayed cells with flow cytometrically diploid DNA content in both the biopsy and the subsequent resection specimen, while 182 carcinomas expressed DNA aneuploid tumour cell lines in matched samples. There were only 8 tumours (3.1%) with heterogeneity in the DNA ploidy status between the biopsy and the resection specimen. These results emphasise the usefulness of incisional biopsies to reliably prognosticate the DNA ploidy status of oral carcinomas.

Use of flow cytometry in the analysis of stage III squamous cell carcinoma of the oesophagus and its association with MIB-1

AIMS

To examine the prognostic and pathobiological importance of DNA content in oesophageal squamous cell carcinomas in Hong Kong Chinese subjects; to evaluate its association with the immunohistochemical proliferative marker MIB-1.

METHODS

Paraffin wax embedded tumour tissue and adjacent normal tissue (control tissue) samples from 45 resected stage III oesophageal squamous cell carcinomas were studied using flow cytometric analysis. The DNA content and the clinicopathological data of these patients were analysed together with the MIB-1 labelling index.

RESULTS

DNA aneuploidy was present in 14 (31%) of the 45 cases. However, the DNA content did not correlate significantly with the age, sex, or survival of the patients, nor the length, location, differentiation and MIB-1 labelling index of the oesophageal carcinomas. The synthetic (S) phase fraction of diploid tumours bore no relation to the patients' survival or MIB-1 score.

CONCLUSIONS

Flow cytometry was not as useful as the MIB-1 labelling index in predicting the biological characteristics of the tumours and the prognosis of patients with oesophageal squamous cell carcinomas. This study does not support the routine use of DNA flow cytometric analysis in oesophageal cancers.