The relevance of flow-cytometric DNA content in the evaluation of lung cancer

Randomised study of adjuvant chemotherapy for completely resected p-stage I-IIIA non-small cell lung cancer

We evaluated the therapeutic usefulness of adjuvant chemotherapy in patients with completely resected non-small cell lung cancer (NSCLC). We also examined the relation between DNA ploidy pattern and the response to chemotherapy. A total of 267 patients with NSCLC (pathologically documented stage I, II, or IIIA) underwent complete resection, and DNA ploidy pattern was analysed. Patients with stage I disease (n=172) were randomly assigned to receive surgery alone (group A) or surgery followed by adjuvant chemotherapy (UFT (oral anti-cancer drug, a combination of Uracil and Tegaful) 400 mg day-1 for 1 year after surgery; group B). Stage II or IIIA disease patients (n=95) were randomly assigned to surgery alone (group C) or surgery followed by chemotherapy (two 28-day courses of cisplatin 80 mg m-2 on day 1 plus vindesine 3 mg m-2 on days 1 and 8, followed by UFT 400 mg day-1 for at least 1 year; group D). Eight-year overall survival rate in patients with stage I disease was 74.2% (95% confidence interval (CI): 64.4-84.0%) in group B and 57.6% (95% CI: 46.4-68.8%) in group A (P=0.045 by log-rank test). In patients with stage II and IIIA disease, no difference was found between groups C and D. Analysis according to DNA ploidy pattern revealed no difference between the groups. Postoperative chemotherapy with UFT was suggested to be useful in patients with completely resected stage I NSCLC. No difference was seen in relation to DNA pattern in any treatment group.

FISH cytogenetics and prognosis in breast and non-small cell lung cancers

BACKGROUND

Interphase cytogenetics by fluorescence in situ hybridization (FISH) has been demonstrated to be a valuable diagnostic tool in effusions from patients with solid tumors. As the next step, we investigated whether certain patterns of numeric aberrations in malignant effusion cells supply prognostic information.

METHODS

From a large series of effusions from patients with solid tumors, 55 effusions from breast cancer and 39 effusions from non-small cell lung cancer (NSCLC) were classified as malignant by cytology or FISH. Tumor cells were classified as FISH aneuploid for chromosome 11 and/or 17 or as not aneuploid. Predominant cytogenetic anomalies and patterns of intratumor cytogenetic heterogeneity were brought in relation to overall survival rate.

RESULTS

There was no difference with respect to overall survival rate when effusions with or without aneuploidy for chromosomes 11 and 17 were compared. Likewise, in effusions with aneuploidy, there was no difference in overall survival rate among patients with different modal chromosome copy numbers (e.g., trisomy vs. tetrasomy 11) or among patients with a low or high grade of intratumor complexity (defined by the intratumor heterogeneity of FISH aneuploidy). In breast cancer, aneuploidy with gain of chromosome 11 was associated with a significantly superior survival rate, suggesting that amplification of chromosome 11 DNA is associated with a less aggressive phenotype.

CONCLUSIONS

Simple chromosomal changes as determined by FISH, such as gain of chromosome 11 copy numbers in breast cancer, may be prognostic. Prospective studies in primary tumors that classify distinct prognostic groups by FISH cytogenetics are warranted.

The potential role of flow cytometry in the diagnosis of small cell carcinoma

CONTEXT

Virtually no information exists in the medical literature on the immunophenotyping of small cell carcinoma by flow cytometry. CD56, or neural cell adhesion molecule, is widely expressed by small cell carcinoma and easily measured by flow cytometry.

OBJECTIVE

To determine the potential usefulness of flow cytometry in the diagnosis of small cell carcinoma.

DESIGN AND SETTING

Retrospective data and archival material on 27 patients were obtained from community hospitals. Specimens (needle aspirations and tissue biopsies) from all patients demonstrated cytomorphologic and flow cytometric features consistent with small cell carcinoma. All measurements were performed at a large reference laboratory. Routine 3- and 4-color flow cytometry using a lymphoma antibody panel, including anti-CD56, was performed. Anti-cytokeratin antibody was also used in the last 12 cases. Immunohistochemical staining with a panel of conventional markers for neuroendocrine neoplasms was performed on available tissue for purposes of confirmation of small cell carcinoma.

PATIENTS

Twenty-seven patients whose tissue specimens showed a clearly defined population of CD45-CD56+ cells by flow cytometry and cytomorphologic features consistent with small cell carcinoma.

INTERVENTIONS

Needle aspiration (n = 3) and tissue biopsy (n = 24) from a variety of sites.

RESULTS

CD56 positivity by flow cytometry was 100 to 1000 times that of the matched isotype control in 25 cases and 10 to 100 times that of the control in 2 cases. Cytokeratin positivity by flow cytometry was found in 12 of 12 cases. Immunohistochemical staining showed positivity for at least 1 cytokeratin and 1 or more neuroendocrine markers in 26 of 27 cases and confirmed the diagnosis of small cell carcinoma.

CONCLUSIONS

Routine flow cytometry can identify a neuroendocrine phenotype that shows a strong correlation with confirmatory immunohistochemical markers in cases exhibiting cytomorphologic features of small cell carcinoma. Flow cytometry appears to complement and may possibly be a satisfactory alternative to immunohistochemical staining when small cell carcinoma is suspected.

Aneuploidy and prognosis of non-small-cell lung cancer: a meta-analysis of published data

In lung cancer, DNA content abnormalities have been described as a heterogeneous spectrum of impaired tumour cell DNA histogram patterns. They are merged into the common term of aneuploidy and probably reflect a high genotypic instability. In non-small-cell lung cancer, the negative effect of aneuploidy has been a subject of controversy inasmuch as studies aimed at determining the survival-DNA content relationship have reported conflicting results. We made a meta-analysis of published studies aimed at determining the prognostic effect of aneuploidy in surgically resected non-small-cell lung cancer. 35 trials have been identified in the literature. A comprehensive collection of data has been constructed taking into account the following parameters: quality of specimen, DNA content assessment method, aneuploidy definition, histology and stage grouping, quality of surgical resection and demographic characteristics of the analysed population. Among the 4033 assessable patients, 2626 suffered from non-small-cell lung cancer with aneuploid DNA content (overall frequency of aneuploidy: 0.65; 95% CI: (0.64-0.67)). The DerSimonian and Laird method was used to estimate the size effects and the Peto and Yusuf method was used in order to generate the odds ratios (OR) of reduction in risk of death for patients affected by a nearly diploid (non-aneuploid) non-small-cell lung cancer. Survivals following surgical resection, from 1 to 5 years, were chosen as the end-points of our meta-analysis. Patients suffering from a nearly diploid tumour benefited from a significant reduction in risk of death at 1, 2, 3 and 4 years with respective OR: 0.51, 0.51, 0.45 and 0.67 (P< 10(-4)for each end-point). 5 years after resection, the reduction of death was of lesser magnitude: OR: 0.87 (P = 0.08). The test for overall statistical heterogeneity was conventionally significant (P< 0.01) for all 5 end-points, however. None of the recorded characteristics of the studies could explain this phenomenon precluding a subset analysis. Therefore, the DerSimonian and Laird method was applied inasmuch as this method allows a correction for heterogeneity. This method demonstrated an increase in survival at 1, 2, 3, 4 and 5 years for patients with diploid tumours with respective size effects of 0.11, 0.15, 0.20, 0.20 and 0.21 (value taking into account the correction for heterogeneity;P< 10(-4)for each end-point). Patients who benefit from a surgical resection for non-small-cell lung cancer with aneuploid DNA content prove to have a higher risk of death. This negative prognostic factor decreases the probability of survival by 11% at one year, a negative effect deteriorating up to 21% at 5 years following surgery.

Prognostic significance of DNA ploidy in squamous cell lung carcinoma: is it really worth it?

BACKGROUND

Many previous studies attempted to associate DNA quantification with prognosis for lung cancer, but there is a divergence of opinion about its value. The purpose of the study was to evaluate the frequency of abnormal DNA content in squamous cell cancer (SCC) and analyze its correlation with late survival rates after surgical treatment.

METHODS

A group of 110 patients surgically treated because of SCC was analyzed. Paraffin-embedded pathologic material underwent cytometric analysis. Postoperative follow-up was performed with standard follow-up visits. The statistical analysis was carried out using Mann-Whitney's U and chi2 tests to compare various variables in both groups. The survival curves were drawn using the Kaplan-Meier method. Clinical staging, regional metastasis, and ploidy, were analyzed with multivariate analysis for having a great impact on survival rates.

RESULTS

Fifty (45%) tumors were DNA aneuploid. The survival rate in patients with aneuploid cancers was worse than in those with diploid tumors and the most frequent cause of death was local recurrence (p < 0.05).

CONCLUSIONS

DNA content abnormalities were found to be an important prognostic factor in patients with SCC. The DNA quantification can select a group of high risk of recurrence even after a radical procedure and set new guidelines for adjuvant therapy.

The prognostic value of DNA content analysis in patients with squamous cell lung cancer treated surgically

The aims of the study were to assess the degree of ploidy and determine whether it had any influence on the remission time and survival of surgically treated patients with squamous cell lung cancer. The results were then related to the clinical staging, grading, size and location of the tumor. Tissue samples of squamous cell lung carcinoma (n=80) resected between 1995 and 1996 in the Department of Thoracic Surgery at University of Medical Sciences in Poznan were prepared using the modified Hedley's method. The measurements were made by means of a Cytoron Absolute flow cytometer. Abnormal (aneuploid) DNA was found in 45% of the tumors. In the 2-year observation period significantly more patients with aneuploid tumors died (75%) than those with diploid tumors (43.2%), P<0.05. No significant correlation was found between the ploidy and frequency of metastasis to regional lymph nodes, tumor size, location or grading. Estimation of the DNA content in cancer cells appears to be a significant prognostic factor. Furthermore measurement of the DNA content can be useful after surgery to estimate the risk of recurrence.

Selection, establishment and characterization of cell lines derived from a chemically-induced rat mammary heterogeneous tumor, by flow cytometry, transmission electron microscopy, and immunohistochemistry

In order to isolate, characterize, and establish culture cell lines with different diagnostic and prognostic significance, derived from multiclonal neoplasms, a ductal infiltrating mammary tumor was induced in rats by 7,12-dimethylbenz[a]anthracene. Clones with different DNA/protein content, being the DI of 1.16, 1.30, and 1.60, respectively, were observed in the primary tumor. Biparametric flow cytometry suggested that the clone at 1.30 is made up of two subpopulations with different protein and slightly different DNA contents. The culture, after a few passages, exhibited the presence of aneuploid cells and the absence of diploid components, demonstrating that only tumor cells survived. The limiting dilution method gave rise to four lines with DI of 1.16, 1.25, 1.30, and 1.50; a mean chromosome number of 45, 46, 47, and 88, respectively; and different morphological and ultrastructural features. These characteristics were stable during the experimental procedure, that is, for about 20 passages. Conversely, the detection of cytoskeletal proteins indicated that the tumor epithelial cells underwent early dedifferentiation into sarcoma-like cells showing markers of stromal cell type and thus exhibiting phenotypic instability in vitro, a feature reported in many advanced human breast cancers in vivo. In conclusion, this cellular model represents the in vivo situation and appears suitable for in vitro studies of tumor cell characteristics and might be used to predict clinical behavior.

Analysis of hyperplastic foci in livers with hepatocellular carcinomas by flow cytometry and AgNOR staining

The phase S ratio in cell cycles were analyzed in livers with hyperplastic foci (HPF) and in livers without HPF by nuclear DNA determinations using flow cytometry, and by staining with argyrophilic proteins of the nucleolar organizer region (AgNOR). Flow cytometric analysis was done on 50 fresh frozen specimens of livers resected from 50 patients with hepatocellular carcinoma (HCC). Paraffin sections from the same patients were analyzed using AgNOR staining. There were 25 cases each with and without HPF. We examined the stage of fibrosis and the grade of inflammatory activity according to the modified Scheuer and Desmet scale. The incidence of HCC recurrence among these patients was also studied. The average phase S ratio of the livers of the patients with HPF was 6.5 +/- 3.2%, and that of the livers of the patients without HPF was 4.0 +/- 2.5%. The ratio differed significantly between the two groups (P < 0.01). The average AgNOR score for HPF lesions of the HPF-positive cases was 1.60 +/- 0.34, that for non-HPF lesions in the HPF-positive cases was 1.29 +/- 0.12, and that for the HPF-negative cases was 1.19 +/- 0.14. Significant differences were found between the average AgNOR scores for HPF lesions of the HPF-positive cases and the non-HPF lesions of the HPF-positive cases (P < 0.01), as well as between the non-HPF lesions in the HPF-positive cases and the HPF-negative cases (P < 0.05). Severe fibrosis (stage 3) and cirrhosis (stage 4) were found in 76% of HPF-positive cases and 48% of HPF-negative cases. The livers of HPF-positive patients were significantly more cirrhotic than those of HPF-negative patients (P < 0.05). The association between HPF and the inflammatory grade was not significant (P > 0.05). The incidence of HCC recurrence among HPF-positive cases was significantly higher than that among the HPF-negative cases (P < 0.05). The average phase S ratio of the recurrent HPF-positive patients was 7.48 +/- 3.48%, significantly higher than that of HPF negative cases (5.57 +/- 3.06%, P < 0.05). Hyperplastic foci of the liver was shown to be a highly proliferative lesion. The proliferative activity of the non-HPF lesions in the HPF-positive patients was also higher than that of the HPF-negative patients. Hyperplastic foci tended to be present in cirrhotic livers, but it was not associated with the grade of inflammatory activity of the liver. Hyperplastic foci may represent an important predictor of recurrence after hepatic resection.

Flow cytometric analysis of tumor DNA profile related to response to treatment and survival in small-cell lung cancer

Flow cytometric (FCM) analysis of tumor DNA ploidy and S-phase fraction (SPF) has been widely used to predict prognosis and treatment response in many malignant tumors, but rarely in small-cell lung cancer (SCLC). In the present study, tumor DNA ploidy and SPF were measured from paraffin-embedded tumor biopsy samples of 36 small-cell lung cancer patients treated with combination chemotherapy and radiotherapy. Aneuploidy was detected in 69% of the tumors. There was a statistically non-significant trend towards more aneuploidy among extensive disease (ED) patients as compared to patients with limited disease (LD): 80% versus 65%, respectively (p = 0.69). The mean SPF was 21.3% (+/-7.6) in patients with LD and 29.0% (+/-5.3) in patients with ED, the difference (7.6%) being statistically significant (p = 0.008, 95% CI for the difference 2.2-13.1). No significant differences was detected in the survival of aneuploid and diploid patients or patients with low (< or = 24.9%) and high (> 24.9%) SPF. Similarly, no significant difference was observed between aneuploid and diploid cases in relation to response to treatment or response duration. It is concluded that the difference detected in the SPF with LD and ED of SCLC may indicate the biological aggressiveness of extensive SCLC.

Cell kinetics analysis of surgically resected non-small cell carcinoma of the lung using the AgNOR silver stain

Cell kinetics analysis of lung carcinoma using DNA flow cytometry has shown a significant correlation with the biological behavior of these neoplasms. Ploidy has shown a more significant association with aggressive behavior. The method may however not be available in all centers. Two counts of the AgNOR silver stain have been correlated with ploidy and proliferative activity (PA). The first count, which is the mean number of AgNOR granules (mAgNOR), correlates with ploidy. The second count is the percentage of cells with > 5 AgNORs/nucleus (pAgNOR), reflects PA. We performed the AgNOR silver stain using the two above-mentioned counts in 41 cases of surgically resected nonâsmall cell carcinoma of the lung. The cases included 14 adenocarcinomas, 24 squamous cell carcinomas, and three undifferentiated nonâsmall cell carcinomas. Follow-up data were available on 36 of the patients, ranging from 10 to 31 months (median 18 months). Thirteen of these patients (36%) developed progressive disease. Adenocarcinomas showed mAgNOR counts suggestive of aneuploidy (> 2.4) in nine of the 14 patients (64%) and 16 of the 24 squamous carcinomas (66%). The adenocarcinomas showed high pAgNOR counts (> 8%) in eight of the 14 cases (57%), in contrast to 15 of the 24 squamous carcinomas (62%). The AgNOR counts did not show any statistically significant correlation with tumor type, grade or stage of disease. The mAgNOR counts were aneuploid in all 13 progressive cases and in only 10 of the 23 stable cases (43%)(P=0.001). The pAgNOR counts were high in 12 of the 13 cases that progressed (92%), in contrast to 10 of the 23 stable cases (43%)(P=0.01). There is no significant evidence that squamous carcinoma of the lung may have a higher incidence of aneuploidy and high PA than adenocarcinoma. Our data also confirm previous data showing that aneuploid lung carcinomas have more aggressive behavior than diploid ones. This study also indicates that, despite the short-term follow-up data, the use of the AgNOR silver stain for cell kinetics analysis of nonâsmall cell carcinoma of the lung may potentially provide useful predictive information on the biologic behavior of lung carcinoma. Long-term follow-up may provide more significant information.