DNA-measurements on formalin-fixed, paraffin-embedded squamous cell carcinomas from different ENT-regions

The relation of radiosensitivity of hypopharyngeal squamous cell carcinoma to DNA ploidy

PURPOSE

The purpose of this study was to examine the radiosensitivity of T1, N0, M0 squamous cell carcinomas of the hypopharynx treated solely with external beam radiation.

MATERIALS AND METHODS

Nuclear DNA content and cell cycle kinetics of 29 archival paraffin-embedded specimens suitable for interpretation were analyzed with an ELITE flow cytometer (Coulter Diagnostics, Opa Locka, FL).

RESULTS

In the radiosensitive group with no evidence of disease for 36 months, 86% of the tumors were diploid and 14% were aneuploid. The mean DNA index for this group was 1.02. In the radioresistant group, with recurrence within 36 months, 80% of the tumors were aneuploid, and 20% were diploid. The mean DNA index for this group was 1.32.

CONCLUSIONS

The findings could have clinical significance because if aneuploidy occurs in an early hypopharyngeal squamous cell carcinoma, the clinician might select surgical resection over radiation therapy.

Flow cytometric analysis of squamous cell carcinoma of the tongue

The purpose of this study was to examine the relationship between anatomic location and the cytogenetic and cytokinetic characteristics of squamous cell carcinoma of the tongue to determine the diagnostic and prognostic potential of flow cytometry. Fifty-two archival, paraffin-embedded specimens of squamous cell carcinoma of the tongue in clinical stages I-IV acquired from 1975 to the present were analyzed with an ELITE flow cytometer (Coulter Diagnostics, Opa Locka, FL). Histopathologic grading was performed by the same pathologist based on tumor differentiation. Of the 40 specimens found suitable for analysis, several correlations were noted. First, as the clinical stage increased, the % S-phase increased. Second, there was no correlation between the histologic grade and the % S-phase. Finally, the % S-phase was higher in those tumors with nodal involvement.

Prognostic factors in squamous cell carcinoma of the oral cavity. A retrospective study of 80 cases

A multiparameter analysis of 80 squamous cell carcinomas of the oral cavity was performed to determine the relative prognostic weight of the location of the tumor, tumor size (T), microscopic grade (G) and DNA content measured by means of flow cytometry. Tumors of the lip have an invariably favourable outcome, while at the other locations they have high rates of mortality (total 5 years of survival less than 35%). A simple statistical analysis was performed using the concepts of death sensitivity (DS), death specificity (DSp), life sensitivity (LS) and life specificity (LSp): the best measure of unfavourable outcome was represented by G3 (DS = 0.69; DSp = 1) and by DNA aneuploidy (DS = 0.76; DSp = 0.45), while the best measure of favourable outcome was represented by G1 (LS = 0.53; LSp = 0.96), T1 (LS = 0.81; LSp = 0.78) and by DNA diploidy of the tumor cells (LS = 0.45; LSp = 0.86). A survival analysis using a step by step regression model according to Cox was carried out in order to evaluate more precisely the relative importance of prognostic factors: traditional prognostic factors (histological grade = G and tumor size = T) showed a strong statistical significance, while DNA content added some additional prognostic information only if associated to the macroscopic features of the tumor.

Squamous cell carcinoma of the renal pelvis: nuclear deoxyribonucleic acid ploidy studied by flow cytometry

From 1944 to 1987, 28 patients with squamous cell carcinoma of the upper urinary tract were treated and also had tumor specimens that were fully evaluable by flow cytometric nuclear deoxyribonucleic acid ploidy analysis: 22 had squamous cell carcinoma of the intrarenal collecting system, 4 had tumors of the ureter, and 2 had tumors of the renal pelvis and ureter. Eight patients (29%) had deoxyribonucleic acid diploid, 11 (39%) tetraploid and 9 (32%) aneuploid ploidy patterns. Ploidy pattern significantly correlated with histological grade and tumor stage. Almost all tumors were histologically of high grade; among the patients with high grade tumors ploidy analysis separated fair and poor prognosis groups. Pathological stage was the dominant clinical variable. A total of 14 patients (50%) had advanced stage disease and all died within 12 months of diagnosis. Nearly all of these patients showed abnormal ploidy patterns and ploidy analysis was not useful prognostically for this group. In contrast, all 3 patients with squamous cell carcinoma of the renal pelvis who were long-term survivors had deoxyribonucleic acid diploid tumors. However, there is no clear statistical evidence from this study that ploidy analysis provides important prognostic information independent of stage and grade for patients with squamous cell carcinoma of the renal pelvis.

Cytophotometry in tumor pathology. A critical review of methods and applications, and some results of DNA analysis

In tumor pathology the quantitation of cellular substances can be of diagnostic value. Microscope cytophotometry and digital image analysis and, on the other hand, flow cytometry are supplementary methods for measuring, each with a typical spectrum of application. The methods are predominantly used for DNA analysis: Static and image cytophotometry are applicable to cytologic and histologic slides preferably for identifying stem lines in tumors of heterogenous morphology and in merely circumscribed lesions (e.g., precancerous lesions). On the other hand, sampling errors due to preselection, and the often low number of cells actually measured, may preclude the possibility of exact cell cycle analysis. This is, in fact, an important additional option of flow cytometry resulting from the high resolution of DNA histograms, which is explained by the large number of cells that can be measured in a short period. Sampling errors in flow cytometry may result from the preparation of single cell suspensions which in certain tumor entities may suppress a varying amount of particularly fragile cells or nuclei. The prognostic significance of DNA ploidy, stem line heterogeneity and S-phase fraction is clearly described in quite a number of tumor entities. Independent of its prognostic value, the cytometric identification of stem lines might be particularly useful in the follow-up of tumor patients, where it may indicate the effectivity of systemic therapy. The development of therapeutic concepts is aptly supported by flow cytometric cell cycle analysis which helps to assess the in vitro effect of combined cytostatics on the proliferative process. Moreover, multiparameter analysis of biopsy samples may provide greater accuracy in characterising individual tumor stem lines and may furthermore help to develop improved protocols for the therapy of solid tumors.

DNA ploidy in oral cavity carcinomas, with special reference to prognosis

Single-cell DNA cytofluorometry was performed on paraffin-embedded tissue of 140 patients with squamous cell carcinomas of the oral cavity. Half of the tumors (71 of 140) were DNA nondiploid. Well-differentiated carcinomas were more often DNA diploid than moderately well-differentiated ones (P less than 0.001; chi-square). The aneuploid tumors responded better to preoperative radiotherapy than did the DNA diploid (P less than 0.001) and polyploid tumors (P less than 0.05; chi-square). Using the multivariate Cox's regression analysis multiploid type tumor, age of the patients and presence of lymph node metastases were the only significant factors influencing survival. DNA diploid tumors in stages I and II had a better prognosis than DNA nondiploid (P less than 0.01; Kaplan-Meier). The reverse was true for stages III and IV, where DNA nondiploid tumors had a better prognosis (P less than 0.05; Kaplan-Meier). Tumor stages (P less than 0.001; Kaplan-Meier) and especially lymph node metastases (P less than 0.0005; Kaplan-Meier) were major prognostic factors. Tumor DNA ploidy may be a complement to clinical and morphologic parameters as a prognostic predictor in squamous cell carcinoma of the oral cavity.

Prognostic implications of nuclear DNA content in head and neck cancer

The nuclear DNA content was measured in formalin-fixed and deparaffined specimens of 296 oral, pharyngeal, and laryngeal squamous cell carcinomas from patients in whom the clinical outcome was known. One hundred ninety (64%) contained cells with abnormal DNA (DNA aneuploid or tetra/polypoid). Only 32% (60 of 190) of the patients with DNA nondiploid cancers survived 5 years, compared with 49% (52 of 106) of the patients with DNA diploid cancers. When the findings were controlled for clinical stage, patients whose tumors were DNA diploid had a survival advantage at each stage. Histologic grading showed less correlation, because only patients with well-differentiated carcinomas had a survival advantage if their tumors were DNA diploid. These data showed that determination of DNA content in cancers of the head and neck can offer prognostic information not provided by other means and enhance the diagnosis of cancer.

Comparison of fresh and paraffin-embedded tissue as starting material for DNA flow cytometry and evaluation of intratumor heterogeneity

Flow cytometric analysis of DNA ploidy and S-phase fraction (SPF) from paraffin-embedded tumors has become an important diagnostic and prognostic tool in clinical pathology and investigative oncology. The present study aimed at elucidating the reliability of the method. About 90% of the 1,400 paraffin-embedded tumors analyzed were evaluable for DNA index and about 70% for SPF, although considerable differences between various tumor types were detected. The within-assay coefficients of variation for determination of tumor DNA index and SPF were 2% and 6%, respectively. Intratumor variation in DNA index was observed in 24% of breast and in 21% of ovarian carcinomas and variation in SPF in 36% and 29% of the respective tumors. Intratumor variation in SPF was greatest in DNA-diploid tumors, which may indicate that SPF values in these tumors may be less reliable owing to variations in the proportions of tumor and nontumor cells. If the methodological variation and the intratumor variation were taken into account, there was a good correlation between DNA indices (r = 0.980) and between SPF values (r = 0.794) obtained from fresh and paraffin-embedded tumors. It is concluded that accurate determination of DNA index and SPF from paraffin-embedded tumors is possible in the majority of cases. Regardless of the type of starting material used for DNA flow cytometry it is advantageous to study several samples from each tumor to account for the intratumor heterogeneity.

Prognostic factors in medullary thyroid carcinomas. Survival in relation to age, sex, stage, histology, immunocytochemistry, and DNA content

Patients with medullary thyroid carcinomas (MTC) were analyzed according to age, sex, and tumor stage. In addition, the MTC were screened for the predominant histologic pattern, immunocytochemical spectrum (60 tumors), and DNA content (DNA cytophotometry and DNA flow cytometry, 25 tumors). These findings were correlated with follow-up data available for 45 of these patients. Forty-eight percent of the tumors revealed a polygonal cell pattern, whereas 22% showed spindle-cell predominance. All tumors contained cytokeratin, chromogranin A, and calcitonin (CT). Calcitonin gene-related peptide (CGRP) was present in 92%, carcinoembryonic antigen (CEA) in 77%, neuron-specific enolase (NSE) in 75%, and vimentin in 53% of cases. Positivity for neurotensin, somatostatin, neurofilaments, bombesin, and alpha human chorionic gonadotropin (a-hCG) and serotonin ranged between 3% and 27%. All MTC were negative for substance P, adrenocorticotropic hormone (ACTH), thyroglobulin (TG), or S-100 protein. Local recurrences and regional lymph node metastases revealed identical staining patterns as the primaries. Prognosis of MTC was found not to be related to histologic features (dominant architectural pattern, cellular shape, presence of amyloid deposits) or immunocytochemical pattern. Instead, survival was significantly correlated to age, sex, and stage of disease. The best prognosis was seen in women younger than 40 years and revealing an early stage of disease. DNA measurements added valuable information in assessing the prognosis of MTC.

DNA cytophotometry in malignant thyroid tumors--use of different evaluation schemes for prognostic statements

Quantitative evaluation of nuclear DNA has been found to provide information on diagnosis and prognosis in a number of malignant tumours and borderline lesions. Using 53 carcinomas of the thyroid with varying differentiation we examined the prognostic information obtained by DNA cytophotometry with respect to clinical outcome, applying three different evaluation schemes. DNA cytophotometry allowed the discrimination of euploid carcinomas with good prognosis from aneuploid tumours with bad prognosis and a generally shortened life span. However, the encapsulated variants of follicular and papillary thyroid carcinomas, with their generally excellent prognosis, exhibited DNA histograms similar to those of their widely invasive counterparts. Thus, the favourable prognosis of these minimal invasive subtypes may primarily be related to the tumours' encapsulation and cannot be ascribed to a particular DNA content. We conclude that DNA cytophotometry can provide additional prognostic information for the individual patient suffering from thyroid carcinoma and may probably lead to an individualization of the therapeutic strategies.

DNA content, malignancy grading and prognosis in T1 and T2 oral cavity carcinomas

Microscopic malignancy grading using the 8-factor system proposed by Jakobsson et al. (1973), the 4-factor system set up by Glanz and Eichhorn (1985), and DNA cytofluorometry were applied to thirteen T1 and thirty-seven T2 squamous cell carcinomas of the oral cavity, 9 with and 41 without metastases. There was a significant correlation between the presence of lymph node metastases (N1) and the malignancy scores (P less than 0.05) and tumour DNA ploidy (P less than 0.01, chi-square). The total number of patients with initial and late lymph node metastases correlated significantly with polyploid nuclei (P less than 0.05) and with malignancy scores (P less than 0.001), which also correlated with regional recurrences (P less than 0.01, chi-square). No remaining tumour after preoperative radiotherapy indicated less risk for local recurrence than if tumour persisted (P less than 0.01, chi-square). The cumulative survival (Kaplan-Meier) was worse for patients with nodal involvement (N1) than for those without (N0) (P less than 0.01), and for patients with poorly differentiated tumours compared with moderately well differentiated (P less than 0.05) and to well differentiated (P less than 0.001). The prognosis was worse for patients with high malignancy scores than those with low (P less than 0.001). DNA diploid tumours had a better prognosis than DNA non-diploid, but the difference was not significant.

Malignancy grading and cytophotometric evaluation of T1 lip carcinomas

Histological malignancy grading using the score system set out by Jakobsson et al. in combination with static DNA cytofluorometry was applied to 20 T1 squamous cell carcinomas of the lower lip, 11 with and 9 without lymph node metastases. The mean malignancy score was 18.0 for tumours with metastases and 13.0 for those without (P less than 0.05, chi square test). Nuclear polymorphism, mode of invasion, vascular invasion, and cellular response were the single factors with the strongest influence. All but 3 carcinomas were DNA diploid, but DNA ploidy and proliferative activity (S-phase) yielded no prognostic information. However, hypertetraploid cells were found in all DNA diploid carcinomas with metastases, but in only half of those without (P less than 0.05).

DNA pattern in oral cavity carcinomas in relation to clinical stage and histological grading

Cytofluorometric DNA analysis was performed in 88 squamous cell carcinomas of the oral cavity. 48% (42/88) of the tumours were DNA non-diploid. The frequency of DNA non-diploid tumours seemed to correlate with the increasing size of the tumour, and the decrease of histological grading, and certainly with the presence of lymph node metastases (p less than 0.001). DNA non-diploid tumours often had shorter duration of symptoms. The S-phase level seemed to increase the less differentiated the tumour but did not correlate either to tumour size or to duration of symptoms. Polyploid nuclei were more common in poorly differentiated tumours (9/10) as compared to well differentiated ones (17/33) (p less than 0.05) and seemed to be more common in tumours with metastases (20/26) than in those without (40/62).

Preoperative irradiation in oral cavity carcinoma. A study with special reference to DNA pattern, histological response and prognosis

The relation between DNA pattern and response to preoperative radiotherapy was studied in 51 patients with oral squamous cell carcinomas operated 4 weeks after irradiation. Small tumors (T1 and T2) showed more pronounced response to radiotherapy than larger ones (T3 and T4), as did DNA aneuploid tumors. Eight of 11 DNA aneuploid tumors showed no remaining tumor in the operation specimen, compared to 6 of 21 DNA polyploid and 2 of 19 DNA diploid tumors. None of 16 patients without demonstrable remaining cancer in the operation specimen had local recurrence. The presence of lymph node metastases was the most important prognostic factor.

Stereology and flow-cytometry of well-differentiated follicular neoplasms of the thyroid gland

A retrospective analysis of surgically resected thyroid nodules by stereology and DNA flow cytometry was performed in 15 follicular adenomas and 15 well-differentiated follicular carcinomas. The criteria for diagnosis were based on the WHO classification of thyroid tumours. By area-weighted random sampling of the visual fields for light-microscopic stereology, any subjective selection bias was precluded, and each point within the embedded neoplastic tissue was given equal probability of being analyzed. 150-250 tumour cell nucleus (TCN) profiles were studied per case by a semiautomatic image analyzing system. Flow cytometric analyses included measurement of the DNA-index, and the percentages of cells in S-phase and in G2/M-phase. Adenomas and carcinomas did not differ in stereological estimates related to TCN size. As examination of the stereological techniques by nested analysis of variance showed that this result cannot be ascribed to inaccurate methods, it follows that determination of TCN size is not a useful tool for the diagnosis of malignancy in well-differentiated thyroid tumours. Both groups included similar proportions of diploid and aneuploid neoplasms. In the carcinoma group the percentage of tumour cells in the G2/M-phase was more than twice as high than in the adenoma group (P less than 0.01). The ratio of short to long TCN profile axis was significantly smaller, and the coefficient of variation of TCN profile area was significantly higher in carcinomas than in adenomas. These findings are consistent with more unequiaxed TCN and higher anisokaryosis in the malignant tumours. Despite the significant differences, however, overlap of data from individual cases precludes the use of these estimates as diagnostic criteria. Pooling of the follicular tumours and dichotomizing the sample by the DNA-index showed that mean TCN profile area is increased and surface-to-volume ratio of TCN is decreased in aneuploid as compared to diploid tumours. This finding indicates that aneuploidy is associated with an increase of TCN size.