Prognostic significance of flow cytometry in lung cancer. A 5-year study

Predicting In Vitro Cancer Cell Survival Based on Measurable Cell Characteristics

Variation in cellular characteristics may determine tumor response and, consequently, patient survival in radiation therapy. However, patient-specific prediction of cellular radiation response is currently unavailable for treatment planning. Thus, the importance of developing a novel approach based on clinically accessible parameters prior to treatment (e.g., by biopsy) is high. The goal of this study was to predict in vitro cancer cell survival through the p53mutation status and the number of chromosomes (NoC). To predict cell survival, we modified a mechanistic radiation response model incorporating DNA repair and cell death, originally designed for normal human cells. Cell-specific parameters of 24 cell lines originating from two laboratories (OncoRay, Dresden, Germany and HIMAC, Chiba, Japan) were considered for modeling. In a first step, we obtained estimates of the only unknown model input parameter genome size (GS) by fitting cell survival simulations onto experimental data. We then analyzed measured and published input model parameters (NoC, p53-mutation status and cell-cycle distribution) to assess their impact on measured and simulated parameters (modeled GS, and measured α, β, SF₂ and γ-H2AX). The resulting data suggested a linear correlation between NoC and modeled GS (R² > 0.93) allowing for estimating GS based on NoC. Applying the estimated GS resulted in predicted cell survival that matched measured data mostly within the experimental uncertainty. The measured radiobiological value β increased quadratically with the cell's modeled GS irrespective of other cell-specific parameters. The measured α and SF₂ split into two groups, depending on the cells' p53-mutation status, both linearly increasing and decreasing, respectively, with modeled GS. Model predictions of foci numbers were, on average, in agreement with published γ-H2AX measurement data. In conclusion, knowledge of clinically accessible parameters (p53-mutation status and NoC) may support patient stratification in radiotherapy based on cell-specific survival prediction testable in prospective clinical trials.

Ploidy and Proliferation Evaluated by Flow Cytometry. An Overview of Techniques and Impact in Oncology

Flow cytometric methods for the assessment of nuclear and chromosomal DNA content and of cell proliferation (including methods based on pulse-chase of bromodeoxyuridine and on monoclonal antibodies against nuclear oncoproteins and proliferation-associated antigens) are illustrated by examples and analyzed critically. The impact of most of these techniques for the study of human solid tumors, with exception of nuclear DNA content evaluation, appears still limited. In particular, new studies of cell lines and clinical material from human tumors using new proliferation markers and multiparameter flow cytometry are necessary to solve a considerable number of methodologic and scientific problems.

Biological correlates of FDG uptake in non-small cell lung cancer

PURPOSE

Each pathological stage of non-small cell lung cancer (NSCLC) consists of a heterogeneous population containing patients at much higher risk than others. Noninvasive functional imaging modalities, such as 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), could play a role in further characterization of NSCLCs. As many factors can influence the extent of FDG uptake, the underlying mechanisms for FDG accumulation in tumors, are still a matter of debate. The aim of the present study was to investigate these possible mechanisms in the primary site of early stage preoperatively untreated NSCLC.

METHODS

19 patients with early stage NSCLC, who had undergone both preoperative FDG-PET imaging and curative surgery, were enrolled in this study. Standardized uptake values (SUVs) were used for evaluation of primary tumor FDG uptake. Final diagnosis, tumor type, tumor cell differentiation and size of the primary tumors were confirmed histopathologically in resected specimens. Histologic sections were analyzed for amount of inflammation and necrosis. Expression of the glucose membrane transporters (GLUT-1 and GLUT-3); the isoforms of the glycolytic enzyme hexokinase (HK-I, HK-II and HK-III); and the cysteine protease caspase-3, was evaluated immunohistochemically.

RESULTS

FDG uptake was significantly higher in squamous cell carcinomas (mean SUV 13.4+/-4.9, n=8) compared to adenocarcinomas (7.1+/-3.3, n=8, p=0.007), or large cell carcinomas (5.9+/-1.9, n=3, p=0.02). The degree of FDG accumulation seemed to depend especially on GLUT-1, GLUT-3 and tumor cell differentiation. The summed standardized values of these three parameters correlated significantly with the SUV (r=0.47, p=0.05).

CONCLUSION

The present study supports the hypothesis that tumor cell differentiation in combination with overexpression of GLUT-1 and GLUT-3 determine the extent of FDG accumulation and that squamous cell carcinomas accumulate more FDG than adenocarcinomas or large cell carcinomas.

Expression of P53 Protein and Dna Flow Cytometry in Gastric Adenocarcinoma: Implications in Patients Treated with Adjuvant Etoposide, Adriamycin and Cisplatin

Aims and background

We evaluated the prognostic value of p53 protein, DNA content and S-phase fraction in patients with adenocarcinoma of the stomach or the gastroesophageal junction treated with adjuvant etoposide, doxorubicin and cisplatin.

Methods and study design

Thirty-five consecutive patients with stage II or III gastric or gastroesophagial junction adenocarcinoma treated with at least two cycles of adjuvant etoposide, doxorubicin and cisplatin after curative gastric resection were included. The expression of p53 protein was determined by immunohistochemistry and DNA content by flow cytometry. The presence of p53 expression and DNA content was compared with clinicopathological features.

Results

Median age was 54 years (range, 31–71). P53 expression was detected in 42.9% (15 of 35) of gastric cancer tissues of the patients. Aneuploidy was observed in 31.4% of patients, and S-phase fraction was more than 10% in 22.9%. P53 immunoreactivity (33.3% vs 47.8%) was more common in advanced disease. There was no association among p53 immunoreactivity, DNA content and S-phase fraction. We also found no significant relationship between p53 immunoreactivity, DNA content, S-phase fraction or other clinicopathological parameters. In univariate analysis, the involvement of lymph nodes was a significant predictor of a poor outcome (P = 0.001). Also, p53-positive patients had a poor survival close to the level of significance (P = 0.051). Likewise, p53 immunoreactivity (P = 0.0071), in addition to lymph node involvement (P = 0.0016), were the independent prognostic factors in multivariate analysis.

Conclusions

This trial supports the results of previous reports that p53 immunoreactivity is a prognostic factor for patients with adenocarcinoma of stomach or gastroesophageal junction treated with adjuvant chemotherapy.

Cytofluorimetric Evaluation of DNA Ploidy in Lung Cancer: A Bronchoscopic Study

The study of the biological characteristics of lung cancer is gaining more and more interest both because of their potential role as prognostic indicators and for therapeutic reasons. The DNA content estimated by flow cytometry in surgical samples of non-small cell lung cancer (NSCLC) has already been demonstrated to be correlated with survival in these patients. From July 1990 to February 1992 we analyzed the DNA distribution of bronchoscopic biopsies from 88 patients with lung cancer (18 small cell lung cancer, SCLC, and 68 NSCLC, two unspecified histology). Twenty-eight tumors (34.6%) had a diploid DNA distribution, while 53 were aneuploid (65.4%). A correlation was found between DNA ploidy and survival. Evaluation of the DNA content in bronchoscopic samples in a large series of patients could determine the role of this analysis prior to surgery in NSCLC and its value as a marker with respect to prognosis and response to therapy in SCLC.

Preoperative F-18 fluorodeoxyglucose-positron emission tomography maximal standardized uptake value predicts survival after lung cancer resection

PURPOSE

A retrospective review of surgically treated lung cancer patients imaged preoperatively by F-18 fluorodeoxyglucose-positron emission tomography ([(18)F]FDG-PET) to determine if the primary tumor standardized uptake value (SUV) predicts survival.

PATIENTS AND METHODS

Non-small-cell lung cancer or carcinoid pT1-4, N0-2, M0 patients treated by R0 surgical resection alone were imaged with computed tomography scan and PET within 90 days before surgery. Prognostic variables were assessed by log-rank test; survival was assessed by the method of Kaplan and Meier.

RESULTS

One hundred consecutive patients (48 men, 52 women) were retrospectively reviewed. Median follow-up for surviving patients was 28 months (range, 16 to 81 months). Median maximal SUV (SUV(MAX)) was 9. The 2-year survival for patients with SUV(MAX) more than 9 was 68% and for those with SUV(MAX) less than 9, it was 96% (P <.01, log-rank test). In a multivariate analysis including pathologic tumor size, involved nodes, histology, and SUV(MAX), only tumor size (T) more than 3 cm and SUV(MAX) more than 9 and their interaction were significant predictors of survival (P =.01, 0.02, and < 0.01, respectively). The 3-year survivals for patients with both T less than 3 cm and SUV(MAX) less than 9 was 97%; for those with T less than 3 cm and SUV(MAX) more than 9, it was 94%; for those with T more than 3 cm and SUV(MAX) less than 9, it was 93%; and for those with T more than 3 cm and SUV(MAX) more than 9, it was 47% (P <.01).

CONCLUSION

In surgically managed lung cancer patients, SUV is a predictor of overall survival after resection. The addition of SUV(MAX) to pathologic tumor size identifies a subgroup of patients at highest risk for death as a result of recurrent disease after resection.

Ability of bivariate cytokeratin and deoxyribonucleic acid flow cytometry to determine the biologic aggressiveness of resectable non-small cell lung cancer

OBJECTIVE

The purpose of this study was to clarify the significance of bivariate cytokeratin and DNA flow cytometry for analysis of the biologic aggressiveness of resectable non-small cell lung cancer.

METHODS

In 92 patients who underwent curative operations, the DNA ploidy status and S-phase fractions of the cancer cell populations inside the tumors were analyzed by a cytokeratin gating technique with paraffin-embedded specimens and were correlated with the surgical results.

RESULTS

Ninety tumors yielded assessable DNA histograms. DNA diploidy was detected in 25 tumors with a mean S-phase fraction of 14.3% +/- 4.7%, and DNA aneuploidy was detected in 65 tumors with a mean S-phase fraction of 15.1% +/- 7.1%. The 5-year overall and recurrence-free survivals were 73.3% and 70.3%, respectively. Multivariate analysis showed that only TNM staging was a prognostic factor after surgery. There was a negative correlation between the logarithms of S-phase fraction and the disease-free interval for 22 patients with proven recurrence (P =.006). The tumors with high S-phase fractions recurred more rapidly than did those with low S-phase fractions.

CONCLUSION

In a bivariate analysis of cytokeratin and DNA flow cytometry in resectable non-small cell lung cancer, the S-phase fraction appeared to be correlated with the disease-free interval. However, DNA ploidy and S-phase fraction were not predictive of either recurrence or survival after operation. Thus DNA flow cytometry may be of limited use for the analysis of the biologic aggressiveness of lung cancer.

The Ki-67 index and survival in non-small cell lung cancer: a review and relevance to positron emission tomography

PURPOSE

We reviewed the current literature to discover the range of studies covering tissue-based and noninvasive methods for determining tumor stage and the prognostic value of staging in non-small cell lung cancer.

DESIGN

Despite refinements in staging of non-small cell lung cancer, each stage remains heterogeneous because each stage contains patients who are at higher risk for recurrence than other patients within the same stage. Tissue-based and noninvasive methods have been investigated to complement tumor stage in assessing non-small cell lung cancer prognosis. The prognostic significance of tumor proliferation assessed by Ki-67 protein expression has been demonstrated in non-small cell lung cancer.

RESULT

Recent positron emission tomography studies have also shown both prognostic value in non-small cell lung cancer uptake of [F-18] fluorodeoxyglucose (FDG) and correlation between non-small cell lung cancer FDG uptake and tumor proliferation.

DISCUSSION

We reviewed the prognostic significance of Ki-67 expression in non-small cell lung cancer and related it to positron emission tomography.

Tl-201 chloride and Tc-99m MIBI accumulation in lung adenocarcinoma in patients with and without distant metastases

PURPOSE

The relation between Tl-201 chloride accumulation by the tumor and its distant metastatic potential were evaluated in patients with lung adenocarcinoma and compared with the same parameters achieved using Tc-99m MIBI.

METHODS

Fifty-six patients with primary lung adenocarcinoma were examined before therapy was begun. They were classified according to the radiologic findings and pathologic diagnosis into two groups: distant metastases and no distant metastases. All patients underwent dual-isotope imaging with Tl-201 chloride and Tc-99m MIBI. Regions of interest were placed over the tumor uptake (T) and contralateral normal lung tissue (N) areas on one transverse view with clearly defined lesions, and the T:N ratio and retention index were calculated.

RESULTS

The early and delayed T:N ratios and retention index using Tl-201 chloride SPECT in the distant-metastases group were significantly greater (P < 0.001 to P < 0.05) than were those in the no-distant-metastases group. There was no significant correlation between the T:N ratio and retention index and distant metastatic potential using Tc-99m MIBI SPECT.

CONCLUSION

Tl-201 chloride SPECT may be more effective than Tc-99m MIBI SPECT for evaluating the distant metastatic potential of primary lung adenocarcinoma.

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.

DNA aneuploidy, S-phase fraction and nuclear p53 positivity in non-small cell lung carcinoma

OBJECTIVES

Surgical resection currently offers the best option for managing non-small cell lung carcinoma (NSCLC) but its efficiency is limited by subsequent tumor recurrence. We evaluated whether flow cytometric study and the p53 gene staining pattern may be useful in this respect.

DESIGN AND METHODS

We took biopsy samples of 40 patients with operable NSCLC to study the frequency of aneuploidy, proliferative activity, and alterations in the p53 tumor suppressor gene and compared them with clinicopathological parameters such as age, gender, smoking, histological type, tumor size, and degree of differentiation. To study DNA content, the nuclei were analyzed by flow cytometry using a FACS flow cytometer (Becton-Dickinson) equipped with an argon ion laser, with a propidium iodide excitation of 488 nm. We used the immunohistochemical technique for p53 analysis in samples of paraffin-embedded tissue corresponding to the same patients from whom fresh tissue was taken.

RESULTS

Nuclear p53 staining was detected in 66.7% of the samples; 69.4% of the cases revealed aneuploid DNA histograms and 59% presented with an S phase fraction of more than 12%. Comparison with clinicopathological parameters showed that p53 protein was associated significantly with histological classification (p = 0.04), gender (p = 0.01), and smoking (p = 0.04).

CONCLUSIONS

Immunodetection of p53 overexpression and DNA ploidy in the bronchial epithelium may be a useful tool in any future multifactorial analysis in such tumors for identifying previous lesions that may progress to malignancy.

Histopathologic prognostic factors in resected adenocarcinomas: is nuclear DNA content prognostic?

BACKGROUND

The pathobiological characteristics of lung adenocarcinoma are still unclear. To identify the factors that may affect the survival of patients undergoing pulmonary resections for adenocarcinoma of the lung, univariate and multivariate analyses were performed for 17 variables of the host, histopathology, nuclear DNA content (NDC), and morphometry of nucleus (nuclear area [NA]) of tumor cells.

METHODS

Seventy-two consecutive patients who underwent resection at the National Cancer Center in Tokyo were studied. They consisted of 45 men and 27 women with an average age of 61.7 years (range, 27 to 83 years). For these patients, NDC and NA were prospectively measured by cytofluorometry and morphometry, respectively. For univariate analysis, 17 factors were studied, including age, sex, TNM stage, diameter of the tumor, pleural involvement, degree of differentiation, scar grade, nuclear atypia, mitotic index, histogram pattern of NDC, mean NDC, number of aneuploid stem cell lines, and mean and SD of NA. A multivariate analysis was performed with Cox's regression model for 16 variables.

RESULTS

In the univariate analysis, 12 factors were significantly related to postoperative survival, including TNM stage, diameter, pleural involvement, nuclear atypia, mitotic index, mean NA, mean NDC, number of aneuploid stem cell lines, and the DNA histogram pattern. In the multivariate analysis, M, T, and the histogram pattern of NDC were significantly associated with survival while N showed a strong, but not significant, association.

CONCLUSIONS

Multivariate analysis of histopathologic prognostic factors indicated that the TNM stage, as well as each component independently, still provided the greatest prognostic value in resected adenocarcinomas of the lung. Among other factors, only NDC significantly affected survival. The importance of NDC measurement should be stressed for predicting the survival after surgical resection more accurately and for selecting patients with a higher risk of recurrence.

[Intratumoral heterogeneity of DNA content in lung adenocarcinoma]

Quantitative microspectrophotometry was performed in 10 resected lung adenocarcinomas for the purpose of studying intratumoral heterogeneity of DNA content. Histologically, there were 3 stage I, 2 stage IIIA, 2 stage IIIB, and 3 stage IV cases, consisting of 3 well, 4 moderately and 3 poorly differentiated cases. The tumors were cut at the greatest dimension and fine needle aspirations were performed from 5 separate areas (central, cranial, caudal, inward, and outward). One of the imprint smears was submitted for cytology and the other for microspectrophotometry using Feulgen staining. Although G0G1 and G2M phase cell populations varied in each specimen, all 5 specimens showed the same DNA histogram in 9 cases. These were 4 aneuploid, 4 polyploid (euploid but not diploid) and only one diploid tumor. Two stem lines were observed in the remaining single case. One of 5 specimens showed aneuploid, the other 4 specimens showed polyploid. Namely, intratumoral heterogeneity was observed in one case. Ther was no relationship between intratumoral heterogeneity tumor size or differentiation. Most lung adenocarcinomas showed DNA stability. Fine needle aspiration specimens obtained from one area of lung adenocarcinoma represent the DNA contents of the entire tumor.

Prognostic significance of DNA content in stage I adenocarcinoma of the lung

PURPOSE

Up to 30% of lung cancers (Stage I) with the most favorable outcome recur within 5 years after surgery. This study reviews the pattern of failure after surgical resection in early lung cancers and determines whether flow cytometric DNA variables were prognostic indicators for survival, disease-free survival (DFS), or distant metastasis-free survival (DMFS).

METHODS AND MATERIALS

Pathologic specimens from 45 patients at The University of Texas M. D. Anderson Cancer Center who underwent surgical resection and mediastinal nodal dissection for stage I (AJCC) adenocarcinomas of the lung were analyzed by flow cytometry for DNA content. Survival was calculated by the method of Desu and Lee. Chi-square and cross tabulation were used in the analysis.

RESULTS

The mean age of the patients was 62 years, and 52.3% were male. All patients were clinical Stage I (T1-2 N0), Karnofsky performance status > or = 70, and had a weight loss <10 lbs. Median overall survival (OS) and DFS were 50 months and 33 months, respectively. OS, DFS, and DMFS at 1, 3 and 5 years were 73%, 57%, and 35%; 63%, 53%, and 45%; and 67%, 56%, and 48%, respectively. Analysis of all 45 patients revealed 86% of patients developing brain metastasis had an abnormal DNA content > or = 30%, whereas 4% of patients with brain metastasis had abnormal DNA content < 30% (p = 0.01). This correlation maintained significance when only pT1/2 lesions were analyzed. There was a significant statistical correlation between abnormal DNA and 5-year OS, with 74% OS for those with abnormal DNA < 30% vs. 42% for > or = 30% (p = 0.036). The 5-year DFS for pT1/2 patients was significantly correlated with abnormal DNA content: 53% for patients with abnormal DNA < 30% vs. 17% for patients with abnormal DNA > or = 30%, respectively (p = 0.03). Of those with %S fraction (%S) < 2, 13% failed locally compared to 41% of those with %S > or = 2. There was a highly significant correlation between DNA index (DNAI) and aneuploid %S: 68% of patients with a DNAI > or = 1.7 had > or = 2.6 aneuploid %S, whereas only 13% of patients with DNAI > or = 1.7 had aneuploid %S < 2.6. (p < 0.001). Grouping the percent of abnormal DNA and overall %S according to low vs. mixed vs. high values correlated with DFS (p = 0.02).

CONCLUSIONS

This study confirms significant correlation between a high DNA index and a higher frequency of brain metastasis, as well as worse OS. Although DNA content variables were not predictive of recurrence at other sites, brain metastasis represents the worst outcome from distant metastasis. Further studies are needed, as well as prospective trials, for evaluating adjuvant therapy in patients with adverse DNA variables following complete surgical resection for early disease. If high-risk patients could be identified after resection, adjuvant therapy (chemotherapy or elective brain irradiation) could be administered.

Thallium-201 single photon emission computed tomography as an indicator of prognosis for patients with lung carcinoma

BACKGROUND

The uptake of thallium-201 (T1-201) in malignant tumors is associated with malignant potential (metastatic potential and proliferative activity). The grade of accumulation of T1-201 in malignant tumors may provide information regarding prognosis.

METHODS

A T1-201 single photon emission computed tomography was conducted 120 minutes after intravenous injection of 111 megabecquerel of T1-201 chloride. The authors calculated the uptake ratio to evaluate the degree of T1-201 uptake in the primary tumor. This ratio was compared with survival time and other prognostic factors.

RESULTS

The authors studied 152 patients (125 men and 27 women). The group of patients with the low T1-201 uptake ratio survived longer than the group of patients with the high T1-201 uptake ratio (median survival, 58 weeks vs. 33 weeks; P = 0.0138 by the log rank test). The multivariate analysis confirmed that the T1-201 uptake ratio was an independent prognostic factor for survival.

CONCLUSIONS

These results suggest that the T1-201 uptake ratio provides independent and objective prognostic information for patients with lung carcinoma.

Clinical and flow cytometric prognostic factors in surgically treated squamous cell lung cancer

A five-year follow-up study of prognostic factors in 207 patients with squamous cell lung cancer (SqLC) radically treated with surgery was investigated. Cellular prognostic indicators for survival times, such as percentage of cells in the S-phase (S-phase fraction, SPF), proliferative index (PI, number of cells in S + G2/M phases) and DNA ploidy, in addition to well known clinical factors were studied. Patients with aneuploid tumours had significantly shorter survival period (P < 0.05) than patients with diploid tumours. However, proliferative rate of the tumours had no influence on patients' survival. Cox multivariate analysis showed that metastases to the neighbouring lymph nodes, tumour diameter > 5 cm and DNA aneuploidy of the tumour cells were the negative factors which affected patients survival. DNA ploidy did not depend on the clinical stage of the tumours.

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.

DNA ploidy in nonmelanoma skin cancer

BACKGROUND

Patients with head and neck squamous cell carcinoma die of locoregional recurrence and those with basal cell carcinoma suffer cosmetic and functional changes from its treatment. Prognostic factors are based upon tumor characteristics and host factors. Flow cytometry can assist with prognostic characterization of nonmelanoma skin cancer.

METHODS

Specimens from 40 sequential patients with head and neck nonmelanoma skin cancers were prospectively obtained at the time of surgery. The patients were followed for four years for local recurrence and metastasis to regional lymph nodes. Samples were prepared from frozen specimens using a modification of the Vindelov procedure.

RESULTS

DNA aneuploidy or tetraploidy and histology of well differentiated squamous cell carcinoma were significantly associated with metastasis to regional lymph nodes. Direct extension of tumor below the adipose tissue was associated with an S-phase greater than 4.1 and a proliferative fraction greater than 5.5. No tumors recurred at the site of surgical resection.

CONCLUSIONS

The measurement of DNA ploidy of well differentiated squamous cell carcinoma, and proliferative capacity or S-phase of both basal cell and squamous cell carcinomas assists in predicting the biologic proclivity for locoregional invasion or metastasis of nonmelanoma skin cancer. Identification of aggressive tumors at the time of surgery may offer the opportunity for prevention of lethal metastasis by using adjunctive therapy.

Chondrosarcoma of bone. A clinical and DNA flow cytometric study

Fifty-two patients with chondrosarcoma were treated in our hospital between 1981 and 1992. Tumours from 21 of the patients were histologically grade I, 19 were grade II, 10 were grade III and two were grade IV. Forty-seven patients were treated surgically and samples for flow cytometric DNA analysis were taken from 38 tumours with a successful measurement in 37 cases. The mean follow-up time was 40 months and during this period 17 of the patients treated surgically developed a local recurrence or metastasis. In one case, a highly anaplastic sarcoma developed after radiation treatment. Only two of the 19 diploid tumours recurred, whereas eight of the 18 aneuploid tumours showed a recurrence. These results indicate that DNA flow cytometry is of prognostic significance in chondrosarcoma and may aid in planning the treatment.

Flow cytometric analysis of the DNA content of adenocarcinoma of the lung, especially for patients with stage 1 disease with long term follow-up

BACKGROUND

To assess the prognostic value of DNA ploidy in adenocarcinoma of the lung, the authors performed a flow cytometric study using paraffin embedded archival material from 160 patients (109 [68%] with aneuploid lesions, 51 [32%] with diploid lesions) who underwent surgical resection from 1982 to 1991.

METHODS

The proportion of DNA aneuploid tumors increased as the disease stage advanced, from 35 of 63 (55.5%) with Stage 1 disease to 15 of 20 (75.0%) with Stage 2 disease, to 40 of 53 (75.5%) with Stage 3a disease, to 19 of 24 (79.2%) with Stage 3b disease. However, this trend was not statistically significant. Comparison of the survival time of the 160 patients with adenocarcinoma of the lung with a median follow-up of 7.8 years revealed that patients with diploid tumors had significantly longer survival than did those with aneuploid tumors (P < 0.01).

RESULTS

Examination by stage showed that patients with Stage 1 disease with diploid tumors had significantly longer survival times than did those with aneuploid tumors (P < 0.05) but that there were no significant differences in clinical outcome in patients with Stage 2, 3a, and 3b diploid tumors.

CONCLUSIONS

Analysis of aneuploid versus diploid DNA content in patients with Stage 1 adenocarcinoma of the lung is concluded to be useful in evaluating clinical outcome and prognosis.

Biological prognostic factors in non-small cell lung cancer

The results of conventional treatments for lung cancer remain poor and long-term survival rates have changed little over the last 10 years. In the same period of time there has been an explosion in the knowledge on the processes of cellular transformation, tumour progression, invasion and metastasis. The major categories of biological events implicated in non-small cell lung cancer include growth factor receptors expression (epidermal growth receptor, p185c-neu), autocrine growth factor production (transforming growth factor alpha), dominant oncogenes activation (ras genes) and deletion of tumour suppressor genes (p53 gene, retinoblastoma gene) and these are some of the abnormalities associated with specific histological types and with poor prognosis. Additional prognostic information can be obtained from the evaluation of the ploidy and proliferative activity of the tumours, carbohydrate antigens expression, presence of neuroendocrine differentiation and the evaluation of markers of the sequential steps involved in the process of tumour dissemination.

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

BACKGROUND

There are few studies of flow cytometric analysis for DNA heterogeneity of patients with superficial carcinoma of the esophagus limited to the epithelium or superficially invading the lamina propria or submucosa.

METHODS

Flow cytometric analysis of cellular DNA content was performed on superficial carcinomas of the esophagus using paraffin embedded blocks of the surgically resected specimens from 56 patients. To evaluate the intratumoral DNA heterogeneity, a total of 141 samples of the 56 tumors were analyzed, depending upon the tumor size.

RESULTS

One or two of the samples was available from 18 of 19 patients with tumors 2 cm or less in greatest dimension, whereas more than three of the samples were available from 22 of 37 patients with tumors 2.1 cm or greater in dimension (P < 0.003). Of 56 tumors, 40 (71.4%) exhibited DNA aneuploidy; DNA heterogeneity was found in 26 tumors (46.4%). The remaining 16 tumors exhibited DNA diploidy. Two of the five tumors that were limited to the epithelium had DNA heterogeneity. The mean dimension of the tumors with DNA heterogeneity was significantly greater (5.8 +/- 2.8 cm) than those exhibiting DNA diploidy (2.3 +/- 1.1 cm) and DNA aneuploidy without heterogeneity (2.9 +/- 2.4 cm). Recurrences after esophagectomy were detected in 6 of the 56 patients; the DNA ploidy pattern of these six patients exhibited DNA heterogeneity.

CONCLUSION

The incidence of DNA heterogeneity increases as tumor size increases and is associated with an increased risk of tumor recurrence after esophagectomy in patients with superficial carcinoma of the esophagus.

High cell proliferation activity determined by DNA flow cytometry and prognosis in epidermoid lung carcinoma

DNA aneuploidy and high cell proliferation activity determined by DNA flow cytometry are known to be associated with poor prognosis in many human malignancies. The aim of the present study was to determine the long-term prognostic value of DNA ploidy and cell proliferation activity in lung cancer. The material consisted of samples from 290 paraffin-embedded lung cancers (171 epidermoid carcinomas, 62 small-cell carcinomas, 26 adenocarcinomas, and 31 others), of which DNA ploidy and cell proliferation activity as defined by S-phase fraction (SPF) was determined by DNA flow cytometry. DNA aneuploidy was found in 61% of the tumours and the mean (+/- SD) SPF was 13.6 +/- 9.5%. DNA aneuploidy was associated with a high T-stage (p < 0.05) in epidermoid carcinoma, but not in small-cell carcinoma or adenocarcinoma. DNA aneuploidy and high SPF were associated with poor survival in epidermoid carcinoma. However, only SPF (relative risk (RR) = 1.80), N-(RR = 2.46) and M-stages (RR = 2.17) were statistically significant predictors of survival according to multivariate analysis. Regression-tree analysis showed that the prognostic value of SPF was restricted to localized (M0-stage) epidermoid carcinoma. Neither DNA aneuploidy nor SPF was associated with survival in small-cell lung carcinoma. In conclusion, SPF is an independent prognostic factor in epidermoid lung carcinoma.

Prognostic value and clinicopathologic correlation of p53 gene mutations and nuclear DNA content in human lung cancer: a prospective study

The aim of this prospective study was to determine whether use of a combination of biomarkers, p53 and nuclear DNA content, led to improved prognosis and clinicopathologic correlation in human non-small cell lung cancer. Nineteen patients undergoing curative resection of primary non-small cell lung cancer were evaluated. Resected tumors were studied by polymerase chain reaction/single strand conformation polymorphism analysis (p53 gene mutations), flow cytometry (nuclear DNA content and cell cycle analysis), and immunohistochemically (p53 oncoprotein). Histologically normal lung was used as an internal control for each patient. Minimum postoperative follow-up was 4 years. p53 gene mutations (5/19 tumors; 26%), tumor ploidy (5/19 diploid), patterns of immunoreactivity, or combination of biomarkers did not appear to correlate with clinicopathologic findings or clinical outcome. Two of three patients with associated second primary malignancies, had squamous cell diploid tumors with p53 gene mutations. We conclude that p53 gene mutations and tumor ploidy may represent different biologic markers for human non-small cell lung cancer. Although trends in improved predictive accuracy were not seen when both markers were incorporated into the tumor analysis, flow cytometry and molecular analysis of the p53 gene may identify patients at increased risk of the development of a second primary malignancy.

Measurement of nuclear DNA content in histological and cytological specimens: principles and applications

Nuclear DNA content can be measured in histological and cytological material by the techniques of image and flow cytometry. The measurement depends on the availability of stoichiometric markers for DNA. Results are expressed in DNA histograms from which tumour DNA ploidy and cell proliferation status can be estimated. Flow cytometry analyses large numbers of cells and gives the most meaningful cell cycle data. Image cytometry is more specifically targeted to the population of interest and can accurately measure rare events. A large body of literature exists relating DNA cytometry to clinical outcome, but there are considerable inconsistencies between clinical series which may be due, in many instances, to problems of histogram interpretation and tumour sampling. Rapid 'user-friendly' systems currently under development may increase the clinical acceptance of DNA cytometry.

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

Cells from a group of 185 patients suffering from malignant tumours (160 non-small-cell lung carcinoma, 13 small-cell lung carcinoma, and 12 non-epithelial tumours) and 6 with benign lung tumours were studied by flow cytometry in order to detect the prognostic value of DNA content. A total of 144 (90%) non-small-cell lung carcinomas (NSCLC) and 8 (62%) small-cell lung carcinomas (SCLC) exhibited aneuploidy. Furthermore 52% (83 patients) NSCLC, 24% (3 patients) SCLC and 50% (6 patients) non-epithelial tumours demonstrated multiclonality. Benign cases showed diploid DNA content. For actuarial survival analysis using the Bergesson and Gage method and the Greenwood variance, 142 patients were selected. Statistical comparisons were made by the use of the t-test for unpaired data between fixed times. No correlation was observed between ploidy and stage, histological grading or treatment modality. A statistically significantly better survival was observed after 12, 18 and 24 months of follow-up for diploid and monoclonal (with the exclusion of hypo- and hypertetraploid) patients. Thus, flow-cytometric DNA analysis may be useful in prognostic assessment of human lung tumours.

Quality control study of the Italian group of cytometry on flow cytometry cellular DNA content measurements

A quality control study on DNA flow cytometry, extended to 43 national laboratories, has been carried out by the Italian Group of Cytometry, using defined fixed suspensions of cultured human leukemia K562 cells and human blood lymphocytes. The participating laboratories were allowed to follow their own staining and measurement protocols. Aliquots of cellular suspension had to be measured three times on the same day and two other times on different days. A large heterogeneity of procedures emerged among participants. The average of mean DNA index laboratory values, from 36 laboratories who sent evaluable data, was 1.68, with a range from 1.49 to 1.97. The coefficients of variation ranged from 2.35 to 9.39% and from 2.79 to 8.5% for diploid and aneuploid peaks, respectively. Statistical analysis of the results showed quite good intralaboratory reproducibility, but statistically significant differences were observed among laboratories, for both DNA indices and coefficients of variation. These differences appear to be consistent. For standardization, it is essential that efforts should be made to identify the main sources of variation and to control them.

The expression of proliferating cell nuclear antigen in paraffin sections of peripheral, node-negative non-small cell lung cancer

Cell proliferation of 40 peripheral, node-negative non-small cell lung cancers (NSCLC) treated with surgery alone was investigated by immunohistochemical analysis with the monoclonal antibody (MoAb) PC10, which recognizes a proliferating cell nuclear antigen (PCNA) in formalin-fixed and paraffin-embedded material. Results were correlated with DNA ploidy and S-phase fraction (SPF) analyzed by DNA flow cytometric study. Mitotic count (MC) was analyzed by light microscopic study and histopathologic features. PCNA immunoreactivity was seen in all samples and confined to the nuclei of cancer, but not to the surrounding, tumor-negative cells; its frequency ranged from 0-70% (median, 15%), and tumors expressed either a low (0-25%, n = 25) or intermediate (26-75%, n = 15) proliferative activity. There was no relationship between PCNA immunoreactivity and tumor stage or among size, histologic type, and mitotic count (MC). Tumors with intratumoral blood vessel invasion (BVI) showed a significantly higher (P less than 0.005) PCNA immunoreactivity than BVI-negative tumors. PCNA scores were significantly higher (P less than 0.005) in DNA aneuploid (n = 22) than in DNA diploid (n = 18) tumors and correlated significantly with the SPF of DNA aneuploid tumors (r = 0.825, P less than 0.0001), but not with diploid tumors (r = 0.002, P = 0.9). Intermediate proliferating tumors had a significantly higher (P less than 0.01) MC than their counterparts. In univariate analysis, significant predictors of survival were tumor classification (T1 versus T2), tumor size (less than or equal to 2.6 cm versus more than 2.6 cm), BVI (BVI-negative versus BVI-positive), MC (less than or equal to 8 versus more than 8), and PCNA immunoreactivity (low versus intermediate). DNA ploidy and SPF did not influence survival significantly. Only PCNA immunoreactivity retained its independent level of significance (P = 0.02) by multivariate analysis. It was concluded that PCNA immunostaining is a simple and clinically useful method for estimating cell proliferation in formalin-fixed, paraffin-embedded tissue of resected peripheral, node-negative NSCLC.

Prognostic significance of tumor proliferative fraction and DNA content in stage I non-small cell lung cancer

Analyses of tumor DNA content and proliferative fraction by flow cytometry have been useful as prognostic determinants in a variety of solid tumors. The significance of this analysis in Stage I (T1N0M0 and T2N0M0) non-small cell lung carcinoma (NSCC) is unestablished. We determined DNA content (ploidy) and proliferative fraction (percentage S phase) on 44 surgically resected Stage I NSCC specimens obtained between 1977 and 1982. All cases had a minimum follow-up of 5 yr. Of the 44 cases, 27 were adenocarcinomas, 15 squamous cell carcinomas, and 2 large cell carcinomas. Of these, 32 (73%) had T1N0M0 lesions and 12 (27%) had T2N0M0 lesions. Overall 5-yr survival was 70%. All patients surviving 5 yr were free of detectable tumor. Patients with T1N0M0 lesions had an 81% 5-yr survival, but those with T2N0M0 lesions had a 42% 5-yr survival (p = 0.009). Analysis of tumor DNA content revealed 35 diploid tumors (79%) and 9 aneuploid tumors (21%). The 5-yr survival for diploid tumors was 77% compared with a 44% 5-yr survival in aneuploid lesions (p = 0.048). The median proliferative fraction was 6%. All patients with a percentage S phase less than 6% survived 5 yr, and 41% (9 of 22) of those greater than 6% survived 5 yr (p less than 0.001). When 8% S phase was used as a cutoff, 93% (28 of 30) below the cutoff survived 5 yr but only 21% (3 of 14) above the cutoff survived 5 yr (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Cellular heterogeneity of DNA/total-protein content in human lung tumors, as determined by flow cytometry

With the aim of distinguishing neoplastic cell sub-populations of different prognostic and diagnostic significance, dual-parameter measurements (DNA/protein) have been simultaneously determined in a (256, 256) channel matrix in lung samples derived from 110 patients affected by neoplastic and non-neoplastic lung diseases. Biparametric analysis demonstrated that cells with abnormally high red fluorescence (i.e., protein content), which is indicative of unbalanced growth, were often observed in malignant tumors as compared with normal lung samples. Furthermore, the dual-parameter analysis allowed recognition of additional aneuploid tumor-cell lines, indicating that the frequency of cytometrically determined diploid tumor is lower than that previously described by DNA monoparametric analysis. The recognition of aneuploid subpopulations by dual-parameter analysis in clinically and histologically negative one-parameter flow-cytometric "diploid" samples assumes important diagnostic value. The results have also shown the presence of multiple protein sub-populations in clones with the same ploidy value, indicating a higher level of cellular heterogeneity than demonstrated by DNA monoparametric measurements.

Relationship between tumor DNA ploidy and regional lymph node changes in lung cancer

Seventy-four patients with lung cancer, resected consecutively from April 1989 to August 1990, were divided into (1) 21 with diploid tumors having a single G0/G1 peak and a coefficient of variation (CV) of 4.9 or less, (2) 18 with peridiploid tumors having a single G0/G1 peak and a CV at 5.0 or more, and (3) 35 with aneuploid tumors having multiple G0/G1 peaks. Aneuploid tumors had higher frequencies of lymphatic invasion and metastasis to the mediastinal lymph nodes. To evaluate the relationship between ploidy tumor status and immunologic competence of the regional lymph nodes, histologic findings and the proportion of killer T-lymphocytes were examined in the dissected lymph nodes. Aneuploid tumors had significantly lower proportions of paracortical hyperplasia and killer T-lymphocytes than did diploid and peridiploid ones in the nonmetastatic lymph nodes of N0 and N1 disease. These findings suggest the possibility that a decline in the antitumor competence of these lymph nodes could cause metastasis to the nodes. The recurrence rates were 19% in diploid, 33% in peridiploid, and 54% in aneuploid tumors, and the 2-year survival rates were 87%, 78%, and 44%, respectively. Peridiploid tumors showed intermediate values between diploid and aneuploid in terms of immunologic competence, recurrence rate, and survival. They were assumed to have a different proportion of aneuploid cells than the other two.

DNA content in correlation with postsurgical stage in non-small cell lung cancer

The relationship between DNA content, TNM stage, tumor size, grade, histology, and disease-free survival was assessed in a retrospective study of patients with non-small cell lung cancer who had undergone resection and complete mediastinal lymph node dissection. Flow cytometric analysis was performed on paraffin-embedded tissue of 90 consecutive patients. The patients were analyzed both as a group and by individual stage. Median follow-up was 11 months (range, 1 to 35 months). Aneuploid tumors were not significantly different from diploid tumors with regard to pathologic TNM stage (p = 0.34), size (p = 0.5), grade (p = 0.5), or histology (p = 0.34). Disease-free survival of patients with aneuploid tumors was not significantly different than that of patients whose tumors had normal DNA content (p = 0.69). DNA content did not correlate with established prognostic factors in patients with non-small cell lung cancer who underwent resection and complete mediastinal lymph node dissection.

Accuracy of the bronchoscopic DNA content analysis of non-small-cell lung carcinoma

To assess the accuracy of the bronchoscopic DNA content analysis, samples of non-small-cell lung carcinomas (NSCLC) were investigated by means of flow cytometry. Samples were dissociated using the detergent Triton X-100. In 58 NSCLC cases, 39 (67%) had DNA aneuploid tumors. We compared the DNA indices of bronchoscopic brushing samples with 21 corresponding surgical samples. In 16 (76%) cases, DNA ploidy of both bronchoscopic and surgical samples were in concordance. In 3 (14%) cases, both bronchoscopic and surgical sample showed DNA aneuploidy, but the number of the DNA aneuploid stem cell lines was different. The cause of these differences was ascribed to the intratumor DNA heterogeneity. In 2 (10%) cases, the bronchoscopic sample showed DNA diploidy, but the surgical sample showed DNA aneuploidy. In these cases, tumor cells obtained by bronchoscopic brushing were so few that the small DNA aneuploid peak was undetectable in the DNA histogram. But the tumor DNA ploidy was evaluated correctly in 90% of 21 cases using bronchoscopic samples. Consequently, despite some drawbacks, the DNA ploidy diagnosis using bronchoscopic samples in this relatively small study, was almost as reliable as surgical samples.

Independent clinical and flow cytometric prognostic factors for the survival of patients with stage I gastric cancer

Paraffin-embedded tumor samples from 151 patients with stage I gastric cancer were analyzed by DNA flow cytometry, and 80 patients received an infusion of bromodeoxyuridine (BrdU) to determine S-phase fraction. S-phase fractions of tumors were measured by the immunohistochemical method using anti-BrdU monoclonal antibody. Of the 151 patients, 81 (54%), and 70 (46%) showed diploid and aneuploid patterns. There was no significant association between DNA ploidy and wall invasion, histologic type, or lymphatic invasion. Aneuploid tumors were associated with positive-vessel invasion. When the DNA ploidy and clinicopathological parameters were simultaneously entered into the Cox regression model, DNA ploidy and wall invasion emerged as independent prognostic parameters. Aneuploid tumors had significantly higher values of BrdU labeling indices than diploid ones. These results indicate that the determination of DNA ploidy patterns may be an important prognostic factor in patients with stage I gastric cancer, and may be useful in deciding the therapeutic schedule of patients with gastric cancer.

Clinical application of flow cytometry for DNA analysis of solid tumors

Recent developments of flow cytometry (FCM) technology which make multiple correlative biological measurements on normal and neoplastic cells is affecting areas of diagnostic pathology as well as research fields, and a general understanding of FCM techniques is essential for pathologists. Today, FCM DNA measurements of tumors also becomes routine in the clinical and/or pathological laboratory for aid in cancer diagnosis and cancer treatment. It can also contribute to diagnosis of tumors as a supplemental method to conventional histopathology, and DNA ploidy and the percentage of S-phase fraction are considered as complementary prognostic parameters independent of the stage of disease. This article reviews clinical applications of flow cytometry focusing on the DNA measurements of solid tumors, and related practical issues, such as the methodology for nuclear DNA measurement, interpretation of DNA histograms and the relationship of DNA ploidy and S-phase fraction to clinical and pathological features of human solid tumors.

A flow cytometric study of non-small cell lung cancer classified as T1N0

Surgical resection currently offers the best chance for cure of non-small cell lung cancer but its efficacy is limited by subsequent tumor recurrence. Even the most favorable cancers (T1N0 tumors) recur 20% to 30% of the time within 5 years and there is currently no way to anticipate precisely which tumors will recur. To test whether DNA flow cytometric study might be useful in this regard, the authors performed a retrospective case-control study of 102 tumors (51 recurrent cases and 51 controls) from a prospective registry of patients with completely resected, meticulously staged T1N0 non-small cell carcinomas. Unbiased relative hazard ratios of recurrence were estimated for ploidy and proliferative rate, as well as for tumor histologic type and clinical variables. Ploidy abnormalities were slightly more common among cases (67%) than controls (57%) but this difference was not statistically significant. Estimation of proliferative rates was possible for 85 tumors but there was no significant difference between cases and controls and proliferative rates were not prognostic of recurrence. In multivariate analyses, the observed predictive value for each of the flow cytometric parameters was modest at best and smaller than that seen for tumor histologic type. These results suggest that flow cytometric analysis has limited value in guiding management of patients with early stage non-small cell carcinoma.

Flow cytometric DNA content of fresh tumor specimens using keratin-antibody as second stain for two-parameter analysis

Studies concerning flow cytometric assessed DNA content reveal problems in interpretating DNA histograms of tumor specimens. The main problems are histograms with a broad coefficient of variation in the G0/G1 fraction; a high G2M fraction and samples with a low percentage of tumor cells. Therefore, in the present study, 382 fresh tumor specimens of carcinomas were analysed routinely, double labeled with, on the one hand, propidium-iodide for assessing DNA content and, on the other, a monoclonal keratin-antibody for marking epithelial and tumor cells. Of the 311 tumor samples, using single parameter analysis 165 (54%) were classified as DNA aneuploid and 146 (46%) as DNA "euploid." By double parameter analysis, 224 (72%) samples were keratin positive and 87 (27%) keratin negative and, of the 224 keratin positive tumors, 175 (78%) were DNA aneuploid and 49 (22%) DNA euploid. The DNA histograms of single and double parameter analysis were compared and it was concluded that in 24 cases (11%) keratin labeling was necessary to recognize DNA aneuploidy. In another 23 (10%) cases, keratin labeling was helpful in assessing DNA aneuploidy. Finally when the results of the 311 samples were combined, 215 (68%) were scored as DNA aneuploid and 99 (32%) DNA euploid. Thus the overall gain in assessing DNA aneuploidy using the double labeling technique is 14%. In conclusion, it is shown that keratin labeling on fresh tumor cell suspensions of epithelial tumors is of additional value in establishing DNA content. Because single parameter DNA assessment is adequate in approximately 60% of the tested samples, the double labeling technique can be performed routinely, or after initial single parameter DNA assessment. Histograms having a broad CV and/or a high G2M are good candidates for the double labeling technique. Using this technique, DNA-content assessment becomes more reliable.

Epithelioid pleural mesotheliomas and pulmonary adenocarcinomas: a comparative DNA flow cytometric study

The DNA flow cytometric characteristics of 23 immunohistochemically and ultrastructurally proven pleural epithelioid mesotheliomas were compared with those of 41 primary pulmonary adenocarcinomas. Multiple, separate tissue blocks were analyzed from each neoplasm to assess DNA heterogeneity. All of the pleural mesotheliomas and 80% of the pulmonary adenocarcinomas manifested a homogeneous DNA ploidy (DNA stability). A significant statistical difference in the ploidy pattern between pleural mesotheliomas and pulmonary adenocarcinomas was noted (P < .001). Mesotheliomas were mostly diploid (78%) and adenocarcinomas were preponderantly aneuploid (88%). The proliferative rate and DNA indexes of the aneuploid adenocarcinomas were significantly higher than those of pleural mesotheliomas (P < .001). There was no statistical significance between the proliferative rates of diploid mesotheliomas and those of adenocarcinomas. We conclude that the DNA flow cytometric characteristics of mesotheliomas are significantly different from those of pulmonary adenocarcinomas. The clinical implications of these findings are discussed.

DNA aneuploidy and low S-phase fraction as favourable prognostic signs in metastatic melanoma

The prognostic value of cellular DNA content in melanoma metastases was investigated by flow cytometric analysis of fresh or paraffin-embedded tumour blocks from 95 consecutive patients referred to the Helsinki University Central Hospital Melanoma Team. Thirty-three per cent of the tumours were DNA diploid and 67% DNA aneuploid. S-phase fractions were lower in DNA diploid than in DNA aneuploid tumours (10.7% and 17.6%). Tumour ploidy and S-phase fraction were shown by multivariate Cox model analysis to be independent prognostic variables and major determinants of survival after first recurrence. Surprisingly, patients with DNA aneuploid tumours and with tumours with low SPF survived significantly longer than those with DNA diploid or high SPF tumours. This exceptional finding of favourable prognosis for DNA aneuploid tumours was more prominent among patients receiving intensive systemic therapy and among patients with stage IV disease, probably indicating a tendency for DNA aneuploid tumours to have higher sensitivity to systemic therapy.

DNA polymerase-alpha as a putative early relapse marker in non-small cell lung cancer. An immunohistochemical study

The authors examined 72 fresh frozen sections of primary lung cancer using a monoclonal antibody for DNA polymerase-alpha (POL-alpha). The percentage of POL-alpha-positive cells was 17.3%. The tumors were divided into two groups. In one group, more than 5% of the POL-alpha-positive cells were designed POL-alpha-positive, and in the other group less than 5% were POL-alpha-negative. The incidence of POL-alpha-positive in men was statistically higher than that in women (P less than 0.05). The incidence correlated with the T (tumor) status, with a significance. Based on data on 43 patients with non-small cell lung cancer and who underwent a complete resection, the 3-year disease-free survival rates of POL-alpha-positive and POL-alpha-negative cells were 42% and 81%, respectively (P less than 0.05). When the patients were restricted to the class of N0 disease or Stage I, all the patients diagnosed as a cases of a relapse of lung cancer were POL-alpha positive. The 3-year disease-free survival rate of patients with POL-alpha negative was 100%. Our data suggest that in cases of non-small cell lung cancer, POL-alpha expression is associated with the extent of malignancy and a recurrence. Thus POL-alpha may prove to be a pertinent marker of an early relapse.