DNA flow cytometry as a prognostic indicator in head and neck cancer

Advances in Intraoperative Flow Cytometry

Flow cytometry is the gold-standard laser-based technique to measure and analyze fluorescence levels of immunostaining and DNA content in individual cells. It provides a valuable tool to assess cells in the G0/G1, S, and G2/M phases, and those with polyploidy, which holds prognostic significance. Frozen section analysis is the standard intraoperative assessment for tumor margin evaluation and tumor resection. Here, we present flow cytometry as a promising technique for intraoperative tumor analysis in different pathologies, including brain tumors, leptomeningeal dissemination, breast cancer, head and neck cancer, pancreatic tumor, and hepatic cancer. Flow cytometry is a valuable tool that can provide substantial information on tumor analysis and, consequently, maximize cancer treatment and expedite patients’ survival.

Graft-versus-host disease: role of inflammation in the development of chromosomal abnormalities of keratinocytes

Graft-versus-host disease (GVHD) is a major risk factor for secondary malignancy after hematopoietic stem cell transplantation. Squamous cell carcinoma (SCC) of the skin and mucous membranes are especially frequent in this setting where aneuploidy and tetraploidy are associated with aggressive disease. The current study is directed at the mechanism of neoplasia in this setting. Unmanipulated keratinocytes from areas of oral GVHD in 9 patients showed tetraploidy in 10% to 46% of cells when examined by florescein in situ hybridization (FISH). Keratinocytes isolated from biopsy sites of GVHD but not from normal tissue showed even greater numbers of tetraploid cells (mean = 78%, range: 15%-85%; N = 9) after culture. To mimic the inflammatory process in GVHD, allogeneic HLA-mismatched lymphocytes were mixed with normal keratinocytes. After 2 weeks, substantial numbers of aneuploid and tetraploid cells were evident in cultures with lymphocytes and with purified CD8 but not CD4 cells. Telomere length was substantially decreased in the lymphocyte-treated sample. No mutations were present in the p53 gene, although haploinsufficiency for p53 due to the loss of chromosome 17 was common in cells exposed to lymphocytes. These findings suggest that in GVHD, inflammation and repeated cell division correlate with the development of karyotypic abnormalities.

Comparison of cisplatin sensitivity and the 18F fluoro-2-deoxy 2 glucose uptake with proliferation parameters and gene expression in squamous cell carcinoma cell lines of the head and neck

Background

The survival of patients with locally advanced head and neck cancer is still poor, with 5-year survival rates of 24–35%. The identification of prognostic and predictive markers at the molecular and cellular level could make it possible to find new therapeutic targets and provide "taylor made" treatments. Established cell lines of human squamous cell carcinoma (HNSCC) are valuable models for identifying such markers.

The aim of this study was to establish and characterize a series of cell lines and to compare the cisplatin sensitivity and 18F fluoro-2 deoxy 2 glucose (18F-FDG) uptake of these cell lines with other cellular characteristics, such as proliferation parameters and TP53 and CCND1 status.

Methods

Explant cultures of fresh tumour tissue were cultivated, and six new permanent cell lines were established from 18 HNSCC cases. Successfully grown cell lines were analysed regarding clinical parameters, histological grade, karyotype, DNA ploidy, and index and S-phase fraction (Spf). The cell lines were further characterized with regard to their uptake of 18F-FDG, their sensitivity to cisplatin, as measured by a viability test (crystal violet), and their TP53 and CCND1 status, by fluorescence in situ hybridization (FISH), polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) with DNA sequencing and, for cyclin D1, by immunohistochemistry.

Results

Patients with tumours that could be cultured in vitro had shorter disease-free periods and overall survival time than those whose tumours did not grow in vitro, when analysed with the Kaplan-Meier method and the log-rank test. Their tumours also showed more complex karyotypes than tumours from which cell lines could not be established. No correlation was found between TP53 or CCND1 status and 18F-FDG uptake or cisplatin sensitivity. However, there was an inverse correlation between tumour cell doubling time and 18F-FDG uptake.

Conclusion

In vitro growth of HNSCC cells seem to be an independent prognostic factor, with cell lines being more readily established from aggressive tumours, a phenomenon more dependent on the molecular genetic characteristics of the tumour cells than on tumour location or TNM status.

DNA histochemical analysis in oral squamous cell carcinoma

BACKGROUND

Recent years have witnessed an increasing emphasis on the role of nuclear DNA and its application in experimental pathological diagnosis to predict prognosis and management of certain neoplasm.

AIMS

to establish objective criteria for the degree of differentiation and histochemical quantitative of nuclear DNA of oral squamous cell carcinoma (OSCC) using microspectrophotometric analysis.

MATERIAL AND METHODS

The study was conducted on histologic materials from patient with OSCC. Two histological grading systems were used; Broder's and invasive front grading system were recorded. Microspectrophotometry was applied on Feulgen-stained sections to determine the quality of tumour nuclear DNA content in two different histological grading systems of OSCC.

RESULTS

Nuclear DNA content increased significantly with decreasing tissue differentiation as well with increasing tumour size.

CONCLUSION

The grading system and DNA content provides more objective and accurate criteria which relate the morphologic finding to biologic activity and growth patterns of oral cancer as compared to histologic differentiation alone.

Tissue Eosinophilic Infiltration

The assessment of stromal invasion in aerodigestive neoplastic squamous proliferation often poses diagnostic and therapeutic challenges. Eosinophilic infiltration is thought to be an adjunctive histologic criterion in determining tumor aggressiveness and invasion. We investigated whether an eosinophilic infiltration in head and neck squamous cell carcinoma measured in biopsies would aid in predicting tumor invasion, response to treatment, locoregional recurrence, and survival.

METHODS

Eighty-seven patients with in situ and invasive squamous cell carcinoma of the head and neck region were evaluated and treated according to their staging. The number of eosinophils per high-power field (eosinophil/HPF), and per 10 high-power fields (eosinophil/10 HPF) at the tumor interface and in tumor tissue, was counted and classified as focally or diffusely present. Each sample was assigned an eosinophilic index of 1-4 based on the number of eosinophils/HPF or 10 HPF. Of 87 patients, 20 patients were followed up after appropriate treatment for locoregional recurrence, distant metastasis, and disease-free survival.

RESULTS

Eosinophilic counts were elevated focally and/or diffusely more frequently in invasive squamous cell carcinoma than in noninvasive tumors. The increased eosinophilic counts, specifically > 10/HPF and > 20/10 HPF, were both significantly associated with stromal invasion. Greater than 10 eosinophils/HPF and/or > 20 eosinophils/10 HPF had the highest predictive power for invasion, with sensitivity, specificity, and positive predictive values of 66%, 94%, 96% and 61%, 100%, and 100%, respectively. Eosinophilic counts greater than 20 eosinophils/10 HPF and eosinophilic indices > 2 were virtually diagnostic for tumor invasion. Patients' biopsies with eosinophilic indices < 2 had a better survival (P = 0.0156). Using Cox regression analysis, we found that most patients' biopsies that had eosinophilic indices > 2 recurred locally or regionally.

CONCLUSIONS

The elevated eosinophilic counts in biopsies and eosinophilic indices in specimens of squamous cell carcinoma of the aerodigestive tract are a histopathologic marker associated with tumor invasion and a clinical predictor for aggressive tumor biology. Similarly, the presence of eosinophils meeting these thresholds in an excisional specimen should indicate the need for additional therapeutic measures and close surveillance to detect earlier locoregional recurrence and possible distant metastasis.

Permanent in vitro growth is associated with poor prognosis in head and neck cancer

OBJECTIVE

The propensity of head and neck carcinomas to grow in vitro and to form a permanent cell line varies. It is not known whether the outcome of patients whose cancer gives rise to permanent in vitro growth differs from that of patients whose cancer cells fail to grow in vitro. The purpose of this study was to find out whether tumor cell capability for in vitro growth is associated with prognosis in head and neck cancer.

MATERIAL AND METHODS

The study group consisted of 30 patients treated for head and neck cancer at the University Central Hospital of Turku between 1987 and 1994, and whose tumor samples had produced a permanent cell line in our laboratory. A control group was selected from patients treated during the same time period and with the same protocols in the same department. The controls were selected on the basis of similar tumor localization, TNM status, histological grade, age, gender and general condition. Tumor samples from 14 of the 30 control patients were also cultured, but did not result in a permanent cell line. The median follow-up time was 54 months in the study group and 52 months in the control group.

RESULTS

The 3-year survival rate of the patients whose cancer gave rise to in vitro growth was only 19%, compared to 68% among the controls (p = 0.001). In a multivariate analysis the propensity of cancer cells to grow in vitro had independent prognostic value, the relative risk of death (RR) being 1.95 (95% CI 1.11-3.42) when compared to cancers that did not produce a cell line. Of the other factors tested, only the primary tumor size (RR 1.75; 95% CI 0.97-3.16) and the blood hemoglobin level at diagnosis (RR 0.97; 95% CI 0.95-1.01) were possibly independently associated with survival.

CONCLUSIONS

The results suggest that the capability of cancer cells for in vitro growth has prognostic significance in head and neck cancer, and that cancer cells that are able to survive and grow in in vitro conditions behave aggressively in vivo. The independence of cancer cells from the paracrine signals produced by the neighboring host cells may enhance cancer cell survival and the metastatic potential in vivo.

DNA ploidy analysis performed prospectively using fresh tumor samples in early glottic carcinoma treated with radiotherapy

PURPOSE

The correlation between the DNA content, determined using fresh tumor tissues, and the macroscopic presentation of the lesion was studied prospectively in patients with T1 glottic carcinoma.

METHODS AND MATERIALS

DNA flow cytometry and fiber-optic endoscopic examination were performed for 30 previously untreated patients with T1 glottic carcinoma. The patients received radical radiotherapy at Aichi Cancer Center Hospital.

RESULTS

In regard to the type of lesion, 4 (80%) were aneuploid, and 1 (20%) was diploid for the invasive type. There was a tendency to show an invasive appearance in aneuploid tumors. With respect to clinical outcome, there were 3 (43%) local recurrences among the aneuploid tumors that invaded the entire length of one vocal cord, 0 (0%) for medium-sized lesions, and 1 (17%) for small lesions. Aneuploid tumors showed a high correlation between lesion size and local control.

CONCLUSIONS

The correlation was not strong enough to conclude that DNA content can replace the macroscopic presentation of the lesion. However, the combination of DNA content and tumor size may help predict radiation sensitivity.

Flow cytometric DNA ploidy analysis of oral cancer comparison with histologic grading

It has been reported that DNA content analysis provides prognostic information eliminating the subjective component involved in routine microscopic decision making. In an attempt to establish a relationship between pathological findings and flow cytometric analysis, 36 formalin-fixed, paraffin-embedded tumour tissue samples were prepared according to Hedley's method and analysed by means of an Epics Profile II flow cytometer. DNA aneuploidy was observed in 15 tumours (41%). A statistically significant correlation was identified between DNA index and mitoses, cellular response and degree of differentiation, but not the ploidy status. It was not possible to identify a significant association of sex, age, and site of the tumour to DNA index. We found a strong correlation between histologic malignancy and DNA index; an increase in DNA index as malignancy score increases was noted. It was concluded that DNA index shows a good correlation with the histologic features of oral cancer, being a complement of differentiation and histologic grading analysis. The use of DNA analysis as a complement to pathological studies would help to diminish the subjective component of assessment of head and neck cancers. Ploidy status was not statistically associated with the differentiation of tumours.

Advances and new concepts in oral and maxillofacial pathology

New techniques in surgical pathology at the cellular and molecular levels offer the clinician help in determining modalities of treatment of specific diseases. In addition to routine staining, adjunctive tests such as immunohistochemical analysis, and the various methods of evaluating nucleic acid have helped make this possible. The efficacy of fine-needle aspiration biopsy has been enhanced by these diagnostic aids that enable the assessment of information from small amounts of tissue.

Tumor DNA content as a prognostic indicator in squamous cell carcinoma of the oral cavity and tongue base

BACKGROUND

Nuclear deoxyribonucleic acid (DNA) content is a prognostic factor in several tumors, and decisions regarding treatment have been made using this parameter. Nevertheless, there is no agreement in head and neck cancer. The purpose of the present study was to ascertain whether tumor DNA content correlated with prognosis in cases of primary squamous cell carcinoma (SCC) of the oral cavity and tongue base.

METHODS

A retrospective study of formalin-fixed, paraffin-embedded tissue from patients with histologically confirmed SCC of the oral cavity and tongue base was performed using flow cytometry. Tumor DNA content was studied in 109 sets of specimens from previously untreated patients. All of them underwent surgical resection at the University "Hospital de La Princesa" between 1982 and 1992. Clinical parameters (age, sex, site of primary tumor, clinical stage, adjuvant therapy received, and disease-free and overall survival) and histologic parameters (histopathologic stage, tumor differentiation, type of inflammatory infiltration, presence of perineural invasion) were recorded in all cases. An exhaustive statistical analysis was applied.

RESULTS

Only the histograms of 93 patients were adequate for consideration. In flow cytometric analysis, DNA aneuploidy was observed in 51 tumors (55%). The proportion of aneuploid tumors was significantly higher in advanced-stage carcinomas (p < .05), tumors with perineural invasion (p < .05) and in men (p < .05). In the 24 patients with lymph node metastasis, the incidence of aneuploidy was 82% (19 of 24) (p < .05). The rate of metastasis and aneuploidy increased as the degree of differentiation decreased (p < .05 for both). Patients with aneuploid carcinomas in both early and advanced stages had shorter relapse-free and overall survival periods than did the patients with diploid tumors (p < .001 for both). A Cox regression analysis demonstrated that ploidy was the single most important prognostic factor in determining relapse and death (p < .001 for both).

CONCLUSIONS

The results indicate that tumor DNA analysis by flow cytometry appears to be useful as a supplement to clinical and histologic evaluation in predicting the tendency of SCC of the oral cavity and tongue base to metastasize to regional lymph nodes and to predict the outcome of the disease.

Mean nuclear area and chromosomal DNA content of squamous cell carcinomas of the oral cavity using computerized image analysis

Morphometric measurements of nuclei may be of prognostic value in some cancers. In this present study we have evaluated the mean nuclear area (MNA) of 50 squamous cell carcinomas of the oral cavity (SCCOC) using computerized image analysis. Since chromosomal DNA content is a reflection of the DNA content in the nucleus, we have evaluated the relationship between MNA and chromosomal DNA. Thirteen tumours had a MNA greater than 49.9 microns2 and 37 had a MNA less than this. Six tumours were classified as hypodiploid, 29 as diploid and 15 as aneuploid. There were 44 node-negative patients and six node-positive. When comparing MNA in these groups, 50 per cent of node-positive patients had a larger MNA whilst only 20 per cent of the node-negative group had a large MNA. The correlation coefficient between MNA and DNA indices was r = 0.75. The greater nuclear size is possibly a reflection of a more aggressive tumour biology in the node-positive patients. We conclude that a large MNA may be a marker of aggressive tumour biology in this group. In the future, we aim to evaluate the prognostic significance of MNA in patients with SCCOC.

Nuclear DNA content using computerized image cytometry of squamous cell carcinomas of the head and neck

Ploidy status using flow cytometry of head and neck cancers may be of prognostic value. We describe the use of image cytometry in ploidy measurement of squamous cell carcinomas of the head and neck (SCCHN). This technique allows only tumour cells to be measured, thereby rejecting debris, artefact and benign cells. Tissue sections were cut from tumours and then Feulgen stained. A total of 60 patients were included in this study, 23 females and 37 males. The data reveals a relationship between ploidy status and the histological differentiation. However, the ploidy status and histological differentiation do not appear to correlate to the clinical stage of the disease. This method of measuring ploidy may be more accurate than flow cytometry and may have a prognostic role in head and neck cancer patients. A study comparing both methods may demonstrate this and we aim to evaluate this in the future.

Retrospective DNA ploidy analysis by image and flow cytometry in head and neck cancer

A retrospective analysis of DNA content (DNA ploidy) was conducted in formalin-fixed specimens from patients with advanced, unresectable head and neck cancer who were treated on a single defined protocol with accelerated fractionation radiation therapy and concomitant cisplatin (Platinol) chemotherapy. Specimens from 31 tumor sites were analyzed by image cytometry using the Feulgen staining method. Fifteen specimens were analyzed by flow cytometry after deparaffinization, nuclear disaggregation, and staining with propidium iodide. By image analysis, 10 (32%) of 31 specimens contained only diploid tumor cells, while 21 (68%) specimens exhibited at least one aneuploid tumor component. Seven of the eight tumors with a single G0/G1 peak by image analysis had a single peak by flow analysis. Five of the seven tumors with multiple peaks by image analysis had multiple peaks by flow analysis. Histology was also reevaluated, and tumor grade was determined, reflecting tumor cell differentiation based on keratinization, mitotic activity and the degree of nuclear polymorphism. For this well-defined patient population managed according to a uniform therapeutic approach, DNA ploidy status and histology provided a suggestion of prognostic separation; however, statistical significance was not obtained, most likely due to the small number of patients.

DNA indices of primary and recurrent squamous cell carcinomas of the tongue and tonsil using image cytometry

Ploidy status of squamous cell carcinomas of the head and neck (SCCHN) from primary and recurrent tonsillar and tongue lesions has not been compared using image cytometry. We have measured and compared the DNA indices in 41 cases. There were 29 tongue SCCHN, 20/29 were primary and 9/29 were recurrent. Mean DNA index (DI) was 1.19 (range 0.70-1.81) and 1.28 (range 0.79-1.94) respectively. There were 12 tonsillar cases, 10/12 primary and two out of 12 recurrent. Mean DI was 0.84 (range 0.57-1.09) and 1.00 (range 0.98-1.02) respectively. Mean DNA indices of both primary carcinomas were lower than the mean DNA indices of the recurrent carcinomas. This difference between the two groups may be a reflection of their tumour biology. However, since our study is small no definite conclusions can be made at this stage. We aim in the future to evaluate the prognostic role of DNA indices of patients with paired primary and recurrent SCCHN. This may be of clinical value and improve the treatment modalities available to this group.

Predictive value of flow cytometric analysis in DNA contents in patients with locally advanced head and neck carcinoma

A retrospective study was performed on 61 eligible patients with stage III and IV (AJC/UICC Staging System) squamous carcinomas of the head and neck region who were treated with definitive radiotherapy with, or without, surgery. DNA contents were measured by flow cytometric analysis of archival paraffin blocks and were correlated with clinicopathological findings, tumour response and patient survival. Comparison of variables including treatment modality was performed for identification of significant prognostic factors. There were 28 diploid, 27 aneuploid tumours and the remaining six were questionable. All patients were followed-up for at least two years or until death. Aneuploid tumours had a significantly higher S-phase fraction (percentage S-phase) (p < 0.001). Neither ploidy nor percentage S-phase were found to have predictive value in tumour response or patient survival within the power of a sample size of 61. Twenty of the 27 (74 per cent) aneuploid tumours had a complete response (CR) whereas 19 out of 28 (68 per cent) diploid tumours achieved CR. Five-year survival by the Kaplan-Meier method was 33 per cent for both aneuploid and diploid tumours. However, nodal stage (N stage) was found to have significant predictive value in both tumour response and patient survival. The complete response for stage N0 patients was 96 per cent, N1 patients 61 per cent, N2 patients 60 per cent and 43 per cent for N3 patients (p < 0.002). Similarly, the five year survival for the N0 and N3 groups of patients was 53 per cent and 29 per cent respectively (p < 0.05).

Study of tumour ploidy in early stages of buccal mucosa cancer

The purpose of this study was to determine whether a tumour's DNA content is a prognostic factor in screening out the biologically aggressive varieties of early buccal mucosa cancer. Seventy-eight cases of early squamous cell carcinoma of the buccal mucosa were studied, including 73 with aneuploid and diploid tumours. T1 and T2 tumours, pathological differentiation, vascular and perineural invasion, and the recurrence and disease-free survival rate in relation to aneuploid and diploid content were ascertained. The recurrence rate in aneuploid tumours is 72%, whereas in diploid tumours it is 6% (P<0.001). A Cox regression analysis demonstrated that tumour ploidy was a prognostic factor in disease-free survival, independent of other clinico-pathological characteristics examined. Aneuploidy is the most accurate predictor of biological aggressiveness of cancer of the buccal mucose. Aneuploid early buccal mucosa cancers should be treated by multimodal therapy to achieve a cure.

P-glycoprotein expression in the squamous cell carcinoma of the tongue base

P-glycoprotein (PGP), which is a product of the multidrug resistance gene (MDR1), is an active transmembrane efflux pump responsible for detoxifying normal cells as well as rendering tumor cells resistant to chemotherapy. It has also been implicated to be expressed by more aggressive cancers. It has not been well described in squamous cell carcinoma of the head and neck. In this investigation, an attempt was made to characterize advanced squamous cell carcinoma of the base of tongue with respect to expression of PGP. Using immunohistochemical techniques two anti-PGP monoclonal antibodies (JSB1 and C494) were used to detect PGP in these lesions, and an attempt was made to correlate levels of PGP staining and various tumor parameters. Usefulness of PGP in predicting survival and time to recurrence was also examined for these advanced lesions. All 33 base of tongue lesions showed staining for PGP with these monoclonal antibodies. This was the first study examining utility of C494 in detecting PGP in squamous cell carcinoma at this site. Increased level of PGP expression was seen in better-differentiated tumors as well as in tumors with diploid DNA. A trend of higher PGP expression and decreased survival emerged. This may represent a true relationship, but inherent heterogeneity of PGP expression within cells cannot be excluded. Both antibodies examined appear to be useful in the investigations of PGP distribution in squamous cell carcinomas of the head and neck sites by immunohistochemical techniques. Prognostic value of the level of PGP expression remains to be seen.

Angiogenesis as a prognostic marker in early head and neck cancer

Experimental evidence suggests that tumor growth beyond the earliest stages is dependent on angiogenesis, or neovascularization, and that angiogenesis may also promote metastasis. Recent clinical studies demonstrate that angiogenesis is a prognostic marker in breast, lung, and prostate cancer. To investigate whether tumor angiogenesis also correlates with metastasis and survival in early head and neck carcinoma, we quantified the microvascularity of 106 primary carcinomas prior to treatment and correlated the counts with eventual outcome after 3 to 15 years of follow-up. Microvessels were stained immunocytochemically for von Willebrand factor and then counted by light microscopy. Microvessels were counted per 200x and 400x fields, and their density was graded from 1 to 4, in the area of most intense neovascularization. We found that neither microvessel counts nor density grades correlated with metastatic disease, local recurrence, or survival in early head and neck carcinoma. These results are in contradistinction to those recently reported for other tumor sites.

Cervical lymph node status and survival in laryngeal carcinoma: prognostic factors

Elective cervical lymphadenectomy often is performed for laryngeal carcinoma to eliminate metastatic disease that escapes clinical and radiographic detection. We investigated characteristics of the primary tumor that might predict cervical lymph node status. We obtained archival tissue from 88 laryngectomies--65 with concurrent cervical lymphadenectomies. Of the 40 clinically negative necks that were dissected, 17% showed lymph node metastasis by pathologic examination. The primary tumors were examined immunohistochemically for expression of epidermal growth factor receptor (EGFR), p53, cathepsin D, proliferating cell nuclear antigen (PCNA), and Ki-67-specific antigen, and by flow cytometry for DNA ploidy-cell cycle analysis. Seventy-seven percent of the cases showed aberrant p53 staining, 99% expressed EGFR, 40% produced cathepsin D, 29% were aneuploid, and 54% had a moderate or high synthesis phase fraction (SPF). High grade, aneuploidy, and tumor vascular invasion independently predicted cervical node metastasis (p < .04 each). Supraglottic locale (p < .16) and a raggedly infiltrating invading margin (p < .13) were weakly associated with node positivity. Advanced clinical T status, the expression of EGFR, p53, and cathepsin D, the PCNA and Ki-67 indices, and SPF did not correlate with node metastasis. The presence of cervical node metastasis predicted poor disease-free (p < .005) and overall survival (p < .04). Advanced clinical T status correlated with brief overall survival (p < .02). Tumor site, histopathologic parameters, ploidy, SPF, PCNA and Ki-67 indices, and the expression of p53, EGFR, and cathepsin D did not affect survival. The presence of vascular invasion, high grade, and aneuploidy may help identify which patients would benefit from elective cervical lymphadenectomy. The correlation of cervical lymph node status and clinical T category with survival confirms the results of previous studies.

Brief report: prognostic importance of cellular DNA content in T1-2 N0 laryngeal squamous cell carcinomas treated with radiotherapy

One hundred fifty-two unselected, consecutive patients with T1-2N0 laryngeal squamous cell carcinoma received radical radiation therapy at the Division of Radiotherapy, Centro di Riferimento Oncologico, Aviano, Italy. Thirty-one (20.4%) of the patients showed disease recurrence or persistence (R/P) after radiotherapy. Flow-cytometric DNA ploidy measurements were performed in 72 cases; 20 had tumor R/P and 52 did not. Tumor R/P occurred more frequently (in 17 [85%] of 20 cases) in patients with diploid tumors. The hazard ratio of recurrence in diploid tumors as compared with aneuploid tumors, after inclusion of all the other significant prognostic factors in a Cox proportional hazards model, was 8.9 (P < .01). Therefore DNA ploidy seems to be an important marker of tumor R/P in patients with T1-2N0 laryngeal carcinoma after radiotherapy.

Flow cytometric analysis of primary and metastatic squamous cell carcinoma of the oral cavity and oropharynx

A retrospective analysis of formalin-fixed, paraffin-embedded tissue from patients with histologically confirmed metastatic squamous cell carcinoma was performed using flow cytometry. Ninety-eight sets of specimens from previously untreated patients with an oral cavity or oropharyngeal tumor and a simultaneous cervical metastatic deposit were analyzed. Normal mucosa and cervical lymph nodes were processed identically and run as controls. All patients underwent surgical resection at Wilford Hall USAF Medical Center or The Eye and Ear Hospital of Pittsburgh between 1980 and 1986. The specimens from 94 patients were technically adequate for interpretation. Diploid histograms in both the primary and metastatic tumors were present in 49 (52%) of 94 patients. Aneuploid histograms in either the primary and metastatic tumors were noted in 45 (47%) of 94 patients. In this group of 45 patients, the primary tumor and cervical metastasis were both aneuploid in 21 (46%), and aneuploid histograms occurred with equal incidence in either the primary or metastasis in the remaining 24 cases. No statistically significant prediction of survival could be made from any correlation with the histograms of either the primary or metastasis. The potential technical problems and limitations of flow cytometry in the determination of DNA content of formalin-fixed, paraffin-embedded tissue and the selection of patients with advanced disease warrant caution in the interpretation of results.

Prognostic significance of DNA ploidy in oral squamous cell carcinomas. A retrospective flow and image cytometric study with comparison of DNA ploidy in excisional biopsy specimens and resection specimens, primary, tumors, and lymph node metastases

Deoxyribonucleic acid ploidy was determined in paraffin-embedded tumor tissue from 116 patients with primary oral squamous cell carcinomas (including 5 carcinomas of the lip and 14 of the tongue) by means of flow cytometry. One hundred six cases were suitable for evaluation (91%). Sixty-eight percent of the cases (n = 72) showed a nondiploid nuclear DNA content. Nondiploidy correlated significantly with presence of lymph node metastases (p < 0.02) but not with tumor stage, grading (World Health Organization), or relapse-free and overall survival. Carcinomas of the lip and tongue turned out to be diploid more frequently than other oral squamous cell carcinomas (p = 0.002). In the 21 cases in which a comparison of DNA content of excisional biopsy specimens and subsequent resection specimens was possible a difference in DNA ploidy was found in one case only. The comparison of primary tumors and their lymph node metastases in 30 cases revealed a discrepancy of DNA content in five cases (17%), which was connected with a shift from nondiploidy to diploidy in four out of five cases. Fifty cases studied in parallel by means of image cytometry with Feulgen-stained tissue sections exhibited a concordance of the ploidy status in 87% and a significant correlation of the DNA index values obtained with both methods (p < 0.01). These results demonstrate that DNA ploidy in oral squamous cell carcinomas is distributed rather homogeneously within the tumors and remains rather stable in the lymph node metastases. Despite a significant correlation between nondiploidy and presence of lymph node metastases, ploidy failed to be a statistically significant parameter for prognosis in oral squamous cell carcinomas in our investigation.

Flow cytometric quantification of the proliferation-associated nuclear antigen p105 and DNA content in advanced head & neck cancers: results of RTOG 91-08

PURPOSE

p105 is a proliferation-associated nuclear antigen which identifies proliferating but not resting cells. The objectives of this Radiation Therapy Oncology Group (RTOG) protocol (91-08) were: (1) to correlate tumor proliferative potential estimated using the p105 assay and deoxyribonucleic acid (DNA) analysis with treatment outcome in patients irradiated for advanced squamous cell carcinoma of the head and neck; and (2) to evaluate the potential of p105 labeling indices as a predictive assay.

METHODS AND MATERIALS

Paraffin blocks of pretreatment biopsies of the primary tumor or metastatic neck nodes of patients with Stage III or IV squamous cell carcinoma of the head and neck treated with radiotherapy alone in three previous RTOG protocols (79-13, 79-15, and 83-13) were retrospectively obtained. From these paraffin blocks, areas of tumor were selected based on histological examinations and sectioned. Nuclei suspensions were then prepared and processed for p105 antibody and DNA staining and subsequent flow cytometric quantification of p105 labeling indices and DNA content and correlation with local-regional control and survival.

RESULTS

Paraffin blocks of tumor biopsies from 148 out of a total of 598 eligible patients were available. Of these, 143 were analyzable. The median and (range) of p105 labeling index (LI-C), p105 labeling index of cells in S phase (LI-S), and p105 antigen density (AD) were: 66.6 (3.85-99.5), 9 (1.55-36), and 93.2 (7.4-628.5), respectively. Deoxyribonucleic acid was diploid in 67 (47%), aneuploid in 22 (15%) and mixed aneuploid/diploid in 54 (38%) patients. There was a strong correlation between AD and DNA ploidy. Antigen density was above median in 91.5% of the aneuploid or mixed aneuploid/diploid tumors, but only in 8.5% of the diploid tumors. Patients with aneuploid or mixed aneuploid/diploid tumors had significantly greater local-regional failures than patients with diploid tumors (p = .0180). Those with p105 LI-C below the median or p105 AD above the median also had significantly greater local-regional failures (p = .0500 and p = .0167, respectively). Patients with p105 AD below the median had significantly better survival than those above the median (p = .0444), although there was no significant difference in survival with respect to DNA ploidy or p105 LI-C. Multivariate analyses showed that T-stage (p = .0001) and p105 AD (p = .0044) were significant prognostic factors for local-regional control, and T-stage (p = .0080), N-stage (p = .0021), primary site (p = .0110), and p105 AD (p = .0326) were significant prognostic factors for survival.

CONCLUSION

These results suggest that flow cytometric quantitation of the proliferation-associated nuclear antigen p105 and DNA content of pretreatment tumor biopsies may be a potentially useful predictive assay in patients irradiated for advanced squamous cell carcinomas of the head and neck.

Head and neck carcinoma--stage at presentation

A prospective study was performed during a 2-year-period. A total of 127 patients presenting with a squamous cell carcinoma of the head, neck and upper aerodigestive tract were entered into the study. Patients were classified according to the primary site, namely: larynx (n = 44), oropharynx (n = 28), hypopharynx (n = 17) and oral cavity (n = 19) and others (n = 19). Patients were staged according to the UICC TNM classification (1987) and the nature and duration of their symptoms were recorded. Sixty-one per cent of patients were found to be presenting with advanced disease (stages 3 and 4): oropharynx--71%; hypopharynx--77%; oral cavity--50%; larynx--34%. No relationship could be established between stage at presentation and duration of symptoms and 53% of patients with advanced disease had been symptomatic for less than 3 months at the time of diagnosis. Only 28% of patients presenting with stage 3 or 4 disease had symptoms for 3 months or longer. Earlier diagnosis will not make a significant impact on the overall prognosis in head and neck cancer.

Flow cytometric analysis of DNA content in squamous carcinoma of the tongue: the relationship to host and tumour factors and survival

Cellular DNA content has been found to be an important prognostic factor in many human tumours, yet within the head and neck region few studies have examined its effect on survival and in those that have, findings differ. Eighty-one consecutive patients with squamous carcinoma of the tongue mainly treated by surgery and post-operative radiotherapy were studied. The DNA content of archival paraffin embedded tumours was measured by flow cytometry. Fifty-seven tumours were diploid and 24 were aneuploid. There was no association between ploidy status and age, sex, tumour size or nodal status. Ploidy status was not related to survival. These findings indicate that analysis of tumour DNA content in squamous carcinoma of the tongue does not provide any additional prognostic information for the individual patient.

Flow cytometric analysis of nuclear DNA content in tongue squamous cell carcinoma: relation to cervical lymph node metastasis

The relationship between DNA ploidy and the incidence of cervical lymph node metastasis in 36 patients with tongue squamous cell carcinoma (SCC) was investigated. The aneuploidy rate of tongue carcinomas was 15/36 (42%), and the mean DNA index (DI) was 1.23, with a range from 0.87 to 3.54. Histologically identified cervical lymph node metastasis was observed in 11 cases, and the incidence of the cervical lymph node metastasis was significantly (P < 0.02) higher in the aneuploid cases (8/15) than in the diploid cases (3/21). Recurrence of the primary lesions was seen in nine cases 0.3-2.5 years after the initial treatment. No obvious difference in the incidence of the recurrence was noted, however, between the diploid (5/21) and the aneuploid (4/15) cases. These results indicate a significant relationship between aneuploidy and incidence of the regional lymph node metastasis, in contrast to the absence of a positive relationship between aneuploidy and recurrence of tongue SCC.

Correlation of the expression of double-stranded RNA-dependent protein kinase (p68) with differentiation in head and neck squamous cell carcinoma

p68 is an inducible protein kinase which is believed to be an important factor in the regulation of both viral and cellular protein synthesis. We have produced a monoclonal antibody (TJ4C4) which specifically detects p68, and which can be used to detect this antigen in formalin-fixed, paraffin-embedded tissues. Because p68 plays an important role in cellular protein synthesis, we hypothesized that it may correlate with normal and neoplastic cellular differentiation. One hundred and seventy-seven head and neck squamous cell carcinoma specimens, representing 82 patients, were studied. The relative amount, frequency, and distribution of p68 expression were determined by microscopic evaluation of ABC immunoperoxidase-stained specimens. A spectrum of immunoreactivity was detected in 156 of 177 tumors, as well as within the normal squamous epithelium. Normal, actively proliferating cells, such as the basal layer of squamous epithelium, expressed comparatively little p68. Increased p68 expression was noted to parallel the morphologic features of cellular differentiation. In neoplastic tissue, p68 expression also increased with the degree of cellular differentiation. These data demonstrate that the expression of p68 parallels the degree of cellular differentiation in squamous cell carcinoma of the head and neck region, as well as within normal squamous mucosa. Therefore, p68 may provide an objective biologic measure of cellular differentiation which does not depend on morphologic features.

Improved DNA content histograms from formalin-fixed, paraffin-embedded liver tissue by proteinase K digestion

An improved method for the enzymatic digestion of formalin-fixed, paraffin-embedded liver tissue for DNA content analysis by flow cytometry is presented. Forty samples of histologically normal liver were alternately digested by the traditional pepsin method or a new method utilizing proteinase K and heat. Sixteen (40%) of the pepsin-digested samples had apparent DNA aneuploid peaks by flow cytometry. False DNA aneuploid peaks were not present in any of the histograms obtained after proteinase K digestion. Microscopy showed that the pepsin-digested samples had residual cytoplasmic remnants which contained fluorescent material. Samples digested with proteinase K had few cytoplasmic remnants. The average G0/G1 coefficient of variation after proteinase K treatment was lower (41%) and the fluorescent intensity higher (128%) than the pepsin-treated samples. The apparent mean S-phase (a combination of S-phase cells and underlying debris) after proteinase K digestion was 35% of the pepsin-treated samples. Primary and secondary tumors of the liver that were DNA aneuploid after pepsin treatment were also DNA aneuploid after proteinase K treatment. A modified digestion protocol utilizing proteinase K and heat can provide superior results for DNA content analysis of formalin-fixed, paraffin-embedded liver tissue.

Tissue markers of potentially malignant human oral epithelial lesions

Tissue markers of potential malignancy have been sought for many years. Cell surface markers, particularly blood group and histocompatibility antigens, have shown great promise and several squamous carcinoma antigens have been identified--but not fully studied in potentially malignant lesions. Growth factors and receptors also need further study. Cytoplasmic markers of potential malignancy have been examined and, of these, keratins, filaggrin, and some carcinoma antigens show most promise. Nuclear analyses have promise but are time-consuming and expensive. Image cytometric analyses appear to be sensitive and predictive: oncogene and tumour suppressor analyses remain to be fully evaluated. New investigative techniques at the cellular and molecular level show increasing promise at defining potentially malignant oral epithelial lesions but more prospective studies are required.

Ploidy status and the response of T1 glottic carcinoma to radiotherapy

Flow cytometric DNA ploidy measurements were performed on formalin fixed paraffin embedded tumour specimens from patients with a T1 glottic laryngeal carcinoma in order to evaluate the role of DNA content in relation to local control. From 1980 to 1987, a consecutive series of 90 patients with a T1 glottic laryngeal carcinoma were treated by radiotherapy with curative intent. Biopsies from 44 of these patients were readily available for DNA flow cytometry. In this group aneuploidy was associated with a significantly higher risk (P = 0.018) of local recurrence within 2 years after completion of radiotherapy (38% vs. 9% in the diploid group).

The prognostic value of cytometric DNA analysis in early stage tongue cancer

In spite of a small size and seemingly localised properties T1 tongue cancer does recur after surgical treatment, locally and/or in regional lymph-nodes, in 30-40% of the patients, and 50% of patients with recurrent disease die because of their cancer. If these patients could be identified by analysis of relevant parameters on the primary biopsy reflecting the biological properties of the tumours more extensive treatment regimes could be given selectively. In 47 primary biopsy specimens from patients with T1N0M0 squamous cell carcinoma of the mobile tongue the aberration in cellular DNA content was significantly higher in the group of tumours which recurred after surgical treatment compared with the non-recurrent group. Tumours in females recurred more frequently than in males. No significant correlation between recurrence and grade of histological differentiation or tumour thickness could be found. Image cytometry DNA analysis provides an objective and reproducible assessment of the nuclear DNA content which could facilitate selection of adequate treatment strategies.

DNA content and histologic growth pattern correlate with prognosis in patients with advanced squamous cell carcinoma of the larynx. The Department of Veterans Affairs Cooperative Laryngeal Cancer Study Group

BACKGROUND

Alterations in DNA content, nuclear morphologic characteristics, and histologic grading have been associated with prognosis in several types of solid malignant neoplasms.

METHODS

To determine the potential usefulness of these factors in predicting tumor behavior in patients with laryngeal squamous cell carcinoma, tumor specimens from 88 previously untreated patients with Stage III or IV cancers were studied. The DNA content and nuclear area (NA) were measured for individual nuclei of each tumor with the use of Azure A-stained frozen sections. An adjusted DNA index (aDI) for each patient was calculated from the slope of the linear regression analysis of nuclear DNA index on NA. Hematoxylin and eosinstained sections were examined and graded systematically for histologic growth pattern. All patients were enrolled in a prospective clinical trial and had laryngectomy and postoperative radiation therapy.

RESULTS

The disease-free survival length was longer and the relapse rates were lower in patients with a low aDI (P less than 0.005) and with tumors exhibiting low-grade growth patterns (P less than 0.001).

CONCLUSIONS

These parameters were independent of staging variables and were better predictors of tumor relapse than traditional clinical staging classifications.

Clonal structural chromosome aberrations in nonneoplastic cells of the skin and upper aerodigestive tract

Cytogenetic analyses of tumors of the skin and upper aerodigestive tract have repeatedly revealed small, pseudodiploid clones characterized by balanced structural rearrangements and a high frequency of cells with nonclonal structural aberrations. However, the lack of common cytogenetic denominators within the different histologic subtypes, the discrepancy between cytogenetic findings and data obtained from flow cytometric DNA content studies, and the occasional identification of tumors with massively rearranged karyotypes indicate that the chromosome rearrangements present in pseudodiploid cells have little to do with the tumorigenesis or progression. Further support for this conclusion, and indirect evidence that the pseudolipid clones probably do not represent the tumor cell populations, derives from the present study in which clonal and nonclonal structural rearrangements were also found in short-term cultures from nonneoplastic skin and pharyngeal mucosa. It is possible that the aberrations are present in subepithelial fibroblast that have accumulated DNA damage due to extensive exposure to potentially carcinogenic agents.

Flow cytometer analysis of oral premalignant lesions: a pilot study and review

In a retrospective study, we examined 34 premalignant lesions of the oral cavity by flow cytometer analysis on formalin-fixed, paraffin-embedded tissue submitted to the University of Tennessee, Memphis, Oral Pathology Laboratory. Three categories of oral epithelial dysplasia were represented (eight mild, seven moderate, nine severe), as well as five epithelial hyperplasias without dysplasia and five fibrous nodules as controls. The DNA index and total proliferative index of each case were calculated. The objective of the study was to determine the amount of epithelial dysplasia necessary in oral lesions before DNA aneuploidy or high proliferative index is detectable and thus determine if flow cytometric analysis can be a diagnostic adjunct for oral premalignant lesions. The results showed that some cases in both the control and dysplastic categories exhibited a high total proliferative index (control = 1, no dysplasia = 1, mild dysplasia = 3, moderate dysplasia = 2, severe dysplasia = 2), whereas only the dysplastic lesions had an abnormal DNA index [8 of 24 (33%)]. The results indicate that flow cytometric analysis may have some limited potential as a diagnostic adjunct in oral premalignant lesions.

The importance of the eosinophil in head and neck cancer

In a previous study, we found tumor-associated tissue eosinophilia (TATE) to be a favorable prognostic indicator for squamous cell carcinoma of the head and neck (p less than 0.05). The present expanded study was undertaken to confirm this finding. The pathology of 120 head and neck tumors was examined for histologic features suggestive of poor prognosis. Ten descriptive histopathologic variables, including two malignancy grading scales, were correlated with DNA flow cytometric data and clinical outcome. No correlation was found between the malignancy grading scales and DNA flow cytometric data or clinical outcome. The present expanded study confirmed with greater statistical significance (p less than 0.001) that high-grade TATE is a favorable prognostic indicator for head and neck cancer. Furthermore, high-grade TATE was associated with the absence of distant metastasis (p less than 0.05). Using a stepwise logistic regression analysis of the clinicopathologic variables in the study, high-grade TATE was the most influential variable affecting clinical outcome, followed by border, stage, and perineural invasion. We conclude that the grade of TATE is a significant prognostic indicator for head and neck cancer. The significance and possible role of the eosinophil in the tumor-host interaction are discussed.

Prognostic factors in head and neck cancer: histologic grading, DNA ploidy, and nodal status

Histopathologic malignancy score and DNA ploidy were investigated as prognostic factors for 72 cases of squamous cell carcinoma of the head and neck (HNSCC). The malignancy grading was based upon four different morphologic characteristics for the tumor cell population and four characteristics for the tumor-host relationship. DNA ploidy was determined through flow cytometry on fresh-frozen tumor samples. The median malignancy score was 20, with 71% of the tumors scoring less than 20 being diploid and 68% of the tumors scoring greater than or equal to 20 being nondiploid (p = 0.003). Univariate analysis revealed that tumors scoring less than 20 and diploid tumors had a significantly higher proportion of complete response and better survival as compared to tumors scoring greater than or equal to 20 and nondiploid tumors, respectively. There was a tendency toward better survival among patients without regional metastasis (N0) as compared with patients with regional spread (N+), whereas the other single factors, patient age, clinical stage, histologic grade, and tumor size did not correlate with prognosis. In N+ patients both malignancy score and DNA ploidy were predictive for survival, whereas in N0 patients only malignancy score was related to prognosis. A multivariate analysis showed that the combination of malignancy score and nodal status were the strongest predictors for survival. DNA ploidy did not contribute further information in this test, due to its close relation with the histopathologic malignancy score.

Prognostic value of various molecular and cellular features in oral squamous cell carcinomas: a review

Recent findings of prognostic value for oral squamous cell carcinomas (OSCCs) which may supplement clinical staging are reviewed. Many reports show that histopathologic grading, measurements of tumor-thickness and DNA-content have independent prognostic value and may thus be of clinical value. Features regarding cells at the invading margins of the tumors are probably of higher prognostic value than features within other parts of the tumors. Reportedly, various other cellular and serum markers have prognostic associations worthwhile further research.

Predicting radioresistance in early glottic squamous cell carcinoma by DNA content

Nuclear DNA content has been implicated as a prognostic factor in an increasing number of tumor types. Current data on the role of DNA content in head and neck carcinoma are conflicting and incomplete. To evaluate the role of DNA content in predicting radioresistance, 29 patients with T1N0M0 squamous cell carcinoma of the glottic larynx who had undergone uniform curative radiotherapy and whose clinical outcome was known had flow cytometric analysis for DNA content performed on their tumors with paraffin-embedded archival tissues. Five aneuploid lesions and 24 diploid lesions were identified. All aneuploid lesions occurred in radioresistant tumors. The probability of an aneuploid tumor failing radiotherapy was highly significant at p = .016. No DNA discordance was found in a sampling of half of the radioresistant lesions' pretreatment and recurrent specimens, for a 100% predictive value of moderate statistical power. On the basis of these findings, patients with aneuploid T1 glottic lesions should be referred for primary surgical therapy.

Prognostic importance of cellular DNA content in head-and-neck squamous-cell cancers. A comparison of retrospective and prospective series

Flow cytometric DNA-ploidy measurements were performed on formalin-fixed tumour specimens from 172 patients with squamous-cell cancers (SCCs) of the head and neck region. One hundred and two samples were chosen retrospectively and a further 70 consecutive patients were analysed prospectively in order to assess the prognostic significance of DNA ploidy and DNA index (DI). There were no statistically significant differences between retrospective and prospective groups in regard to age, sex, TNM stage, ploidy or DI. Sixty-seven percent of patients were aneuploid (65% retrospective; 71% prospective). The proportion of aneuploid tumours was significantly higher among poorly differentiated tumours. Survival analysis using Cox multivariate regression modelling revealed that DNA aneuploidy and increasing DI were significant independent prognostic factors for both relapse-free and overall survival. The relapse and death rates among aneuploid subjects were approximately 3 times as high as those for diploid subjects. Patients with a DI greater than 2.11 (hypertetraploidy) experienced a 6.6-fold higher death rate than diploid subjects. These results provide strong support for the incorporation of DNA ploidy profiles into the clinical management of patients with head and neck cancer.

Elective radical neck dissection in epidermoid cancer of the head and neck. A retrospective analysis of 853 cases of mouth, pharynx, and larynx cancer

A retrospective analysis of 853 patients with cancer of the mouth, pharynx, and larynx operated on over a 30-year period was performed. Four hundred fifty-seven of them had a radical neck dissection (RND) at some point. Five hundred ninety patients had no clinically positive nodes (N-o) necks at the time of primary treatment; 99 of these had elective neck dissection, whereas 95 others had a delayed RND when nodes became clinically involved. Twenty-three percent of all N-o patients had microscopically involved nodes and less than half of these were among those patients selected for elective RND. Furthermore, 58% of those patients who had elective RND did not have positive nodes. Comparative analysis of elective RND, delayed therapeutic RND after clinical appearance of nodes, and composite operations for patients with N1-N3 disease indicates little difference in disease-free survival when the nodes in the elective RND were positive microscopically for tumors (56%, 49% and 47% respectively). It thus seems that elective RND offers no real advantage over a careful watchful waiting approach in most patients.

DNA content in nasopharyngeal carcinoma

DNA analysis by flow cytometry was performed on tissue blocks from 41 patients with nasopharyngeal carcinoma. The histologic slides were reviewed by a pathologist and blindly classified according to the World Health Organization classification. The paraffin-embedded blocks were processed to obtain individual nuclei, which were then stained with propidium iodide. The nuclei were analyzed on a flow cytometer. Excluding 10 uninterpretable histograms, the remainder were interpreted blindly and classified as diploid or aneuploid. The Cox proportional hazards survival model was used to analyze stage, histology, radiation dose, and ploidy. We observed more diploids (23 of 31; 74%) than aneuploids (eight of 31; 26%). The 2-year survival rate of diploids was 55%, compared with 25% of aneuploids (P less than .05). We conclude that ploidy status is an independent prognostic factor in nasopharyngeal carcinoma.

A clinical and flow cytometric analysis of patients with nasopharyngeal cancer

Abnormal cellular DNA content, a hallmark of malignancy, is known to be an important prognostic factor in many human solid tumors; however, no data have been published on whether cellular DNA content carries prognostic significance for patients with nasopharyngeal cancer (NPC). Archival, formalin-fixed, paraffin-embedded pathology specimens representing pretreatment tissue biopsies from 55 patients (41 men and 14 women) with NPC were analyzed for cellular DNA content in a retrospective fashion from 1968 to 1988. Individual tumors were classified as either lymphoepithelioma, squamous cell, or anaplastic carcinoma, and were staged according to International Union Against Cancer (UICC) criteria. All patients were treated with curative intent using a 4 to 6 MeV linear accelerator to total doses ranging from 50 to 60 Gy in 4 to 6 weeks. The overall 5-year actuarial survival for all 55 patients was 44.4% (men, 41%; women, 52%). Survival by T stage was as follows: T1, 65%; T2, 51%; T3, 36%; and T4, 27%. Similarly, the 5-year survival rate declined as the bulk of nodal metastases increased: N0, 62%; N2, 50%; N3, 37%; and N1, 25%. Patients who had anaplastic carcinoma had a 5-year survival of 73%, those with lymphoepithelioma had a 60% survival, and those with squamous cell cancer (SCC) had a 30% survival. There was a statistically significant difference in 5-year survival between patients with SCC and those with nonkeratinizing histologies (P less than 0.05). In addition, there was a significant association between patients older than 40 years of age with SCC and patients younger than 40 years of age with nonkeratinizing malignancies (P less than 0.01). Of the 55 tumors successfully analyzed, 22 (40%) were diploid and 33 (60%) were aneuploid. The mean coefficient of variation (CV) of all 55 samples was 6.17%. There was no significant difference in 5-year survival between patients with diploid and those with aneuploid tumors (48% versus 42%). Furthermore, there was no statistically significant survival difference between aneuploid and diploid tumors within any one histologic subgroup. There was also no significant survival difference related to the DNA index. The results indicate that the extent of local tumor spread is still the most important prognostic factor for patients treated with radiotherapy for NPC. The data support the conclusion that patients with lymphoepithelioma and anaplastic carcinomas have a superior survival to patients with squamous cell carcinoma.(ABSTRACT TRUNCATED AT 400 WORDS)