Prognostic value of deoxyribonucleic acid aneuploidy in primary non-small-cell lung carcinomas and their metastases

Prognostic value of DNA ploidy: 5-year follow-up of patients with resectable squamous cell carcinoma (SCC) of the lung

This study was designed to show the relation between DNA-ploidy in patients with resectable lung cancers and their 5-year survival rate. The results are compared with those from our 2-year follow-up study of the same group of patients published in 2000. The group of 80 patients with SCC who underwent lung resection between 1995 and 96 were re-analyzed. For the statistical analysis the hazard Cox model and an exponential multiple regression model were used. The survival curves were drawn using the Kaplan-Meier method. DNA-aneuploidy was found in 45% of cancer tumors. There was no statistically significant correlation between aneuploidy and gender, age, cancer staging or grading. In the 3-year follow-up the survival rate in patients with aneuploid type tumors was significantly lower than in those with the diploid type. However, this difference was not found after 5 years of follow-up. Tumor ploidy was an independent prognostic factor only in patients between 55 and 60 years of age. The mortality rate in patients with aneuploid tumors was mainly the result of distant metastases while, in patients with diploid tumors, local recurrence was the main reason for death. In the first three years after surgical resection patients with aneuploid tumors are at higher risk of distant metastases than patients with the diploid type. Tumor ploidy can be recognized as an independent prognostic factor in younger (55-60) patients. Aneuploidy promoted the occurrence of early distant metastases while the diploid type was associated with late (after 3 years) local tumor recurrence.

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.

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.

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.

Surgery for brain metastases from nonsmall cell lung carcinomas and tissue cultures from the resected specimens

Between 1978 and 1989, 44 patients underwent 44 thoracotomies and 55 craniotomies for nonsmall cell lung carcinoma (NSCLC) and its brain metastases. Patients ages ranged from 20 to 75 years. There were no intraoperative mortalities. The 2-, 3-, and 5-year survival rates following the initial craniotomy were 23%, 10%, and 10%, respectively. Patient survival did not differ with respect to solitary or multiple metastases or the sequence of surgery for primary lesion and brain metastases. Moreover, there was no significant difference in survival between patients treated by surgery alone and those receiving surgery followed by whole brain radiotherapy. After 1985, in vitro tissue culture was attempted using freshly resected specimens of brain metastases obtained from 30 consecutive cases. Of those specimens, nine (30%) were successfully established as permanent cell lines. Eight of those cell lines revealed DNA-aneuploid pattern on flow cytometric analysis. The remaining cell line was not analyzed. Karyotype analysis was also performed in eight of nine established cell lines. Two adenocarcinoma cell lines showed the presence of +3p- chromosome, and three showed +7q- chromosome as recurrent chromosomal abnormalities. These findings provide new evidence concerning the presence of 3p- and/or 7q- marker chromosomes in certain adenocarcinoma cell lines established from brain metastases. The prognosis was poorer in the group with in vitro tumor growth than that in the group showing no in vitro tumor growth. These cell lines established from brain metastases may be useful materials not only for studying the biological characteristics and chemo-sensitivity testing, but also for estimating prognoses after resection of brain metastases.

The role of video-assisted thoracic surgery for carcinoma of the lung: wedge resection to lobectomy by simultaneous individual stapling

Despite a plethora of technologic advances, there has been only minimal improvement in the surgical treatment of carcinoma of the lung during the past 15 years. The advent of video-assisted thoracic surgical (VATS) techniques, however, is opening up new vistas and providing unimagined options for more accurate diagnosis, more precise staging, and more specific resections of lung tumors. Currently, a voluminous surgical literature supports tissue conservation, in selected patients, for the curative resection of peripheral malignant nodules less than 2 cm in diameter. Because these lesions are very accessible to a VATS resection, such procedures can be satisfactorily performed to meet the individual needs of the patient (ie, wedge, subsegmental, segmental, and sublobar resections, as well as traditional or SIS-lobectomy [simultaneous individual stapling of hilar structures]). As the technology advances, members of other specialties are beginning to develop a keen interest in the treatment of carcinoma of the lung. If thoracic surgeons are to prevail in the treatment of carcinoma of the lung, for the benefit of their patients, they must remain vigilant, informed, and versatile in their approach to this disease. This involves learning, understanding, and incorporating these new technologic advances into their armamentarium.