Prognostic significance of cytoplasmic p53 oncoprotein in colorectal adenocarcinoma

Mutation of p53, a tumour-suppressor protein, leads to overexpression of the protein and loss of its tumour-suppressive properties. In some tumours (eg, breast) p53 expression is related to well-known prognostic factors, but findings in colorectal tumours are equivocal. We have used the polyclonal antibody CM1 to investigate nuclear and cytoplasmic p53 expression in colorectal tumours and to assess their relations with prognosis. Of 293 colorectal adenocarcinomas, 71 (24%) showed p53 expression in the nucleus alone, 30 (10%) showed p53 in the cytoplasm alone, and 43 (15%) showed both nuclear and cytoplasmic expression. Nuclear p53 expression showed no relation with survival or Dukes' stage of the tumour. However, the frequency of cytoplasmic expression increased with advancing Dukes' stage (chi 2 for trend 11.18, 1 df, p = 0.0008) and cytoplasmic expression was associated with poor survival (rate ratio 2.3 [95% CI 1.6-3.3], p < 0.0001). Among tumours of Dukes' stage A-C, cytoplasmic expression showed prognostic value independent of nuclear staining, grade of differentiation, and Dukes' stage (2.3 [1.4-3.7], p = 0.0021). We conclude that cytoplasmic expression of p53 may be a useful biological indicator of prognosis in colorectal adenocarcinoma.

Significance of S-phase fraction and hormone receptor content in the management of young breast cancer patients

Tumours from 336 breast cancer patients under the age of 50 were analysed for hormone receptor content and by DNA flow cytometry. Sixty-six percent of the tumours were positive for estrogen receptors (ER), 60% were progesterone receptor (PR) positive and 42% showed DNA diploid profiles. DNA hypodiploid tumours were relatively frequent (7%), especially in patients aged 40 years or less (11%). S-phase fraction (SPF), with a mean of 10%, correlated significantly with receptor status, DNA ploidy, lymph node status, tumour size and age. With a median follow-up period of 34 months, the distant recurrence-free interval was independently predicted by lymph node status, tumour size, SPF and PR content. Amongst the 212 patients who had not received adjuvant systemic treatment, receptor status was, in addition to lymph node status and SPF, independently related to distant recurrence rate. A high SPF identified a subgroup with high recurrence rate, comprising approximately one third of the node-negative patients. Similarly, the one third of node-positive patients who had PR-positive tumours with a low S-phase fraction formed a subgroup with low recurrence rate. We conclude that hormone receptor assays and DNA flow cytometry should be useful tools in the management of breast cancer patients less than 50 years of age.

Relationships of DNA ploidy, S-phase fraction and hormone receptor status to tumor stage in breast cancers detected by population screening. The South-East Sweden Breast Cancer Group

Cellular DNA content was analyzed by flow cytometry and estrogen and progesterone receptors by an immuno-biochemical method (EIA) in a consecutive series of 807 frozen breast-cancer samples. Before the beginning of the study, a mammography screening program had been introduced in the region where the tumors were diagnosed. Forty percent of the tumors were judged as DNA diploid, of which 86% were ER-positive. The proportion of ER-positive tumors among non-diploids was significantly lower, or 73% (p less than 0.001). S-phase fraction (SPF) was estimated in 691 cases (86%), with an overall mean of 8.4%. DNA ploidy as well as ER and PR status were independently related to SPF. Unlike the results obtained in most older series, the biological variables correlated significantly with tumor staging factors such as lymph-node status and tumor size. Patients with nodal involvement, especially those with 4 positive nodes or more, more often had tumors which were receptor-negative, DNA aneuploid and of high S-phase rate. Large tumor size was significantly related to lower frequencies of receptor positivity and strongly related to DNA aneuploidy and high S-phase fraction. Multiple linear regression analysis showed that these relationships were mainly due to the associations of SPF with the other variables. S-phase fraction was the only independent factor predicting nodal status, while DNA ploidy in addition to SPF was associated with tumor size. In fact, DNA ploidy (p less than 0.001), ER and PR status (p less than 0.001, p = 0.002), nodal status (p = 0.04) and tumor size (p less than 0.001) were all independently related to SPF.

Interrelations between cellular DNA content, S-phase fraction, hormone receptor status and age in primary breast cancer. A series of 1,342 consecutively detected tumors. South-East Sweden Breast Cancer Group

Estrogen and progesterone receptors were assessed by an immuno-biochemical method and DNA content was analysed by flow cytometry in a consecutive series of 1,342 frozen breast cancer samples. Forty-six percent of the ER-positive tumors were DNA diploid compared to 23% among ER-negative cases. The proportion of ER-/PR- cases was highest among hypertetraploid tumors (45%) and lowest among DNA diploids (13%). While receptor positivity and DNA ploidy were strongly related, no differences in mean receptor levels were detected when comparing DNA diploid and aneuploid cases of receptor positive tumors. In receptor positive tumors ER content--but not PR content--increased with age. S-phase fraction (SPF) was estimated in 1,165 cases (87%) with an overall mean of 8.6%. Tumors with high S-phase levels and DNA hypodiploid tumors were significantly more often found in younger than in older patients. The frequency of DNA hypodiploidy was less than 1% among women older than 75 years, while it was 8% among those aged 40 years or younger. S-phase fraction was inversely related to ER and PR status. However, while mean SPF gradually decreased with increasing levels of PR, no significant difference in S-phase fraction was seen for ER concentrations just above the cut-off level for receptor positivity. Tumors positive for both receptors showed the same pattern of DNA ploidy as ER+/PR- tumors while differences in S-phase fraction were observed between the groups. These results support that PR status better than ER status reflects hormone dependent growth in breast cancer.

ras p21 expression in relation to DNA ploidy, S-phase fraction and prognosis in colorectal adenocarcinoma

ras p21 expression, as indicated by the monoclonal antibody ras 11, was estimated using immunohistochemistry on 69 primary colorectal adenocarcinomas. Also, DNA ploidy and S-phase fraction (SPF) were analysed with flow cytometry. Positive staining for ras 11 tended to be more common in DNA non-diploid tumours (P = 0.11), but was significantly correlated with high SPF (P = 0.038). Positive ras 11 staining, Dukes' stage, DNA ploidy and SPF were related to the recurrence-free interval of patients with Dukes' A-C tumours (P = 0.0014, P = 0.023, P = 0.035 and P = 0.040, respectively). ras 11 staining was a prognostic factor independent of both Dukes' stage and DNA ploidy (P = 0.011). The results indicate that pan ras p21 expression is associated with proliferative activity and has an independent prognostic value in colorectal adenocarcinoma.

Ras p21 expression in relation to histopathological variables and prognosis in colorectal adenocarcinoma

Ras gene protein products (p21) reacting with the monoclonal antibodies ras 11, DWP, R256 and E184 were studied with an immunohistochemical method which was applied to 17 normal and 79 colorectal adenocarcinoma specimens. Normal colorectal epithelium showed positive staining for ras 11 in 35% of the cases, but not for DWP, R256 and E184. The antibodies showed positive staining in colorectal adenocarcinomas in 76, 53, 29 and 35% of the cases respectively. The degree of staining for ras 11 was significantly related to the grade of differentiation and increased from Dukes stage A to C. Strong staining for ras 11 predicted a significantly shorter recurrence-free interval (p less than 0.001). In Cox's regression analysis, the degree of staining for ras 11 was a prognostic factor independent of the grade of differentiation and Dukes stage (p less than 0.01). The results indicate that the enhanced expression of pan ras p21 may provide an important biological marker for determining prognosis in colorectal adenocarcinomas.

DNA flow cytometry on breast carcinomas: comparison of a detergent and an enzyme-detergent preparation method

In this study we have compared two different preparation methods for DNA flow cytometry on breast cancer. Tumour cell suspensions from 49 breast cancers were analysed on a Facscan flow cytometer. In seven of 49 cases, additional aneuploid peaks were found after enzyme/detergent treatment (E/D), not seen after the detergent (D) preparation. S-Phase fractions were significantly higher after D than after E/D preparation (mean values, 15 and 8%, respectively), although the correlation was high between the two methods. S-Phase fraction estimated after background correction diminished the differences between the two methods (mean values, 8 and 6%). Furthermore, the fraction of G2/M cells were generally greater with the D method. These differences can be explained by increased number of cell doublets and nuclear fragments after D compared to E/D preparation. This clearly shows that the preparation method influences the result of DNA flow cytometry on human breast cancers.

Cytometric and histopathologic features of tumors detected in a randomized mammography screening program: correlation and relative prognostic influence

Cytometric determination of S-phase fraction and ploidy type was performed on 430 tumors detected within a randomized trial of mammographic screening. The results were compared to several histopathologic features. A high S-phase fraction was estimated in tumors with a high grade of malignancy and other histopathologic findings related to rapid tumor progression, including lack of tubule formation, a high mitotic index, marked nuclear pleomorphism, multifocal cancer growth, tumor emboli in lymphatic and blood vessels, tumor necrosis, and inflammatory reaction. DNA aneuploidy was correlated with a high malignancy grade, frequent mitoses, a high degree of nuclear pleomorphism, vascular invasion, necrosis, and the presence of noninvasive ductal carcinoma. Both cytometric variables were inversely related to the degree of elastosis. Positive nodes, large tumor size, DNA aneuploidy, a high S-phase fraction, high grade of malignancy, lack of tubule formation, as well as high mitotic index and pleomorphism, presence of multifocal cancer, and vascular invasion, predicted a significantly shorter distant recurrence-free interval after a median follow-up time of 46.6 months. Elastosis and the presence of estrogen and progesterone receptors indicated favorable prognosis. In the multivariate analysis, only lymph node status, tumor size, S-phase fraction, and multifocal growth pattern had independent prognostic value.

Influence of S-phase fraction on metastatic pattern and post-recurrence survival in a randomized mammography screening trial

Using static cytofluorometry, S-phase was determined on the primary tumors of 421 patients with breast carcinomas in stages I-III diagnosed 1981-85 during the second and third screening rounds of a randomized trial evaluating the effect of mammographic screening. Through December 1988, 82 patients had developed local and/or distant recurrence, 51 of whom had died of cancer during the same period. The distribution among sites of recurrence differed between patients with tumors detected by mammography screening and cancers diagnosed due to clinical symptoms. The mean S-phase fraction was highest in patients with liver or brain metastases and lowest in patients with metastases in subcutaneous and cutaneous tissue and lymph nodes only. In univariate analysis, survival after first recurrence was significantly associated with the site of primary recurrence, the disease-free interval, and node status and tumor size at diagnosis, as well as the S-phase level. The median survival period was 31.3. months for patients with a S-phase fraction below 6%, and 10.7 months in cases with S-phase exceeding 10%. Neither ploidy nor the estrogen receptor content had significant influence on post-recurrence survival. In Cox's multiple regression analysis, only metastatic site, disease-free interval, and S-phase fraction showed significantly independent prognostic value.

Cytometric characterization and clinical course of breast cancer diagnosed in a population-based screening program

A randomized controlled trial evaluating mammographic screening was started in two Swedish counties in 1977. In one of these, Ostergötland county, the authors performed static cytofluorometry on 161 cancers detected at the second and third screening rounds, 50 interval cancers, and 219 cancers appearing in the nonscreened control group during the same time period. The median follow-up time was 42 months. No difference in mean S-phase was found between screening and control group cancers, but interval cancers, appearing between two screenings, had increased mean S-phase levels (P = 0.01) compared to both of the other groups. A high S-phase fraction was associated with distant recurrence in both node-negative and node-positive tumors. Aneuploid tumors were more often found in the control group (67%) and among interval cancers (72%) than among screening detected cancers (55%, P = 0.02). In Cox's multivariate analysis, including all patients, the lymph node status, tumor size, estrogen receptor content, and S-phase all contributed independent prognostic information about the clinical course. DNA ploidy predicted the outcome in simple but not in multivariate Cox's analysis. When analyzing screening-detected cancers separately, only the S-phase significantly predicted distant recurrence in multivariate analysis. In tumors with local recurrence, a high S-phase implicated an increased, although not statistically significant, risk for distant recurrence. Survival with metastatic disease was significantly influenced by the S-phase level (P = 0.002). The authors conclude that S-phase fraction provides valuable kinetic information related to the clinical outcome for all stages of the disease and serves as a prognostic factor in screened populations, which have tumors predominantly in early stages.

Prognostic value of DNA ploidy and S-phase fraction in relation to estrogen receptor content and clinicopathological variables in primary breast cancer

Tumors from 472 women with primary breast cancer were analyzed by flow cytometry. Divided into four categories, DNA ploidy showed significant association with disease recurrence and mortality. When allowance was made for its correlation with nodal status and estrogen receptor (ER) content, DNA ploidy did not add prognostic information. S-phase fraction was estimated in 290 DNA histograms. In contrast, it was significantly related to recurrence and mortality when controlling for nodal status, tumor size and ER content. When the follow-up was divided into two periods DNA ploidy and S-phase fraction showed association with disease recurrence in the first period only (less than 2.5 years), while the association with mortality was valid for both periods. Light scatter was measured in 234 samples. A low light scatter variability for the stemline nuclei was related to a high recurrence rate during the early follow-up period. In conclusion, DNA flow cytometry adds prognostic information concerning breast cancer patients.

Cytophotometric estimation of cell proliferation in breast cancer. Correlation to the clinical course during long-term follow-up

Tumours from 117 patients with breast cancer operated during a 5-month period 1975-1976 were investigated by absorbance scanning cytophotometry. The relations of these data to breast cancer recurrence and death during a follow-up period of 8.5 years were analysed using Cox's proportional hazards model. When individually tested, nodal status, grade of malignancy and high rates of proliferation, as indicated by cells in S-phase, were statistically significant predictors of the clinical outcome. The risk ratio associated with S-phase decreased significantly over time from primary treatment. No significant relation was found between DNA-ploidy or tumour size and the clinical course. In the multivariate analysis, based on 76 patients, nodal status alone was a significant prognostic factor.

A rapid system for static cytofluorometry enabling the simultaneous determination of nuclear size and DNA content

A measuring technique enabling the simultaneous determination of nuclear size and DNA content by single cell cytofluorometry is described. The system is based on a Leitz MPV cytophotometer, a Zeiss scanning stage and a microcomputer system. Cells to be measured are not positioned in the ordinary way, but are passed through the excitation light beam. In this way rapid measurements are achieved. Further, an estimate of the object diameter is calculated from the pulse shape obtained as the fluorescence is recorded continuously by using a circular measuring aperture, congruent with the excitation light field. Repeated measurements of nuclei stained with Hoechst 33258 showed a high reproducibility for DNA content with a coefficient of variation (CV) below 1% and an acceptable precision for nuclear area with a mean CV of 7%. Nuclear area estimated by the method was well correlated to area determined from photographs (r = 0.986). Disintegrated samples from eight patients with breast cancer were analyzed and compared to Feulgen-stained samples analyzed by scanning cytophotometry. Scatter diagrams illustrating DNA content and nuclear size showed essentially the same distribution with the two methods. We conclude that the system may be a rapid alternative when fluorescence together with object size are quantified in slide preparations.

Cellular DNA pattern, S-phase frequency and survival in papillary thyroid cancer

A series of 150 patients with papillary thyroid cancer diagnosed in Iceland during the 30-year period from 1955 through 1984 was retrospectively analyzed. Flow cytometric analysis of archival paraffin-embedded material was used to study the prognostic significance of cellular DNA content and s-phase frequency. DNA-aneuploidy was found in 12% of the tumors. It was significantly more common in the elderly, in moderately and poorly differentiated carcinomas, in males and in tumors with a high proportion of s-phase cells. Multivariate analysis using stepwise Cox's model showed aneuploidy, age at diagnosis, lymph node metastasis and tumor extension beyond the thyroid capsule as independent prognostic factors. The frequency of cells in s-phase was generally low (mean 2.7%). Patients with high s-phase frequency (greater than 2.5%) had less favorable prognosis than patients with low values (less than or equal to 2.5%).

Comparison of static and flow cytofluorometry for estimation of DNA index and S-phase fraction in fresh and paraffin-embedded breast carcinoma tissue

DNA index, S-phase and G2/M fractions were measured in breast carcinomas before and after paraffin-embedding. Unfixed tumors were analysed with flow cytometry, while cells prepared from fixed and paraffin-embedded tumors were analysed with both static cytometry and flow cytometry. Cells for static cytometry were prepared with pepsin and cells for flow cytometry were prepared with trypsin. In 44 of 51 paraffin-embedded tumors, analysed with flow cytometry, both DNA index and S-phase fraction could be estimated. There was a strong correlation between the three methods of obtaining DNA indices and S-phase fractions, but this was not true for G2/M fractions. Histograms from flow cytometry of archival material were corrected for background. We conclude that cells prepared from formalin-fixed and paraffin-embedded breast cancer tissue can yield reliable estimation of DNA index and S-phase fraction.

A comparison of static cytofluorometry and flow cytometry for the estimation of ploidy and DNA replication in human breast cancer

332 primary invasive breast carcinomas were analysed by static cytofluorometry and flow cytometry. The ploidy distributions were similar, and 54% of the tumors were judged DNA aneuploid by both methods. The coefficient of variation of the G0-G1 peaks ranged from 2.0 to 8% with both techniques, but the mean was somewhat lower with flow cytometry--4.1%, compared to 4.9% for the static measurements. The proportion of S-phase cells was possible to estimate from 80% of the flow histograms and 70% of the static histograms. S-phase was not estimated from the static histograms if less than 150 tumor cells were measured. With 160 tumors S-phase was measured by both methods. The range was 0 to 27% with the static measurements and 0.7 to 25% with flow cytometry. Corresponding mean values were 7.6% and 8.2%, which are similar to thymidine labeling index results with breast cancers reported in some studies. A close correlation was obtained (r = 0.927) comparing S-phase fractions estimated from aneuploid tumors with flow cytometry and static cytofluorometry if more than 200 cells were measured with the latter. The proportion of S-phase cells was significantly lower for the diploid tumors. We conclude that both techniques can be useful for the estimation of DNA ploidy and replication in human breast cancer.

Use of formalin fixed, paraffin embedded tumours for estimation of cellular DNA content and S-phase fraction by static cytofluorometry

Sections with a thickness of 50 micron from 34 formalin fixed, and paraffin embedded tumours were deparaffinized and hydrated and the cells were disaggregated with pepsin. The cells were stained with Hoechst 33258 and a rapid method for static fluorometry was used. DNA ploidy and the fraction of cells in S-phase were estimated and compared with results obtained with freshly prepared cells. The coefficients of variation for the tumour stemlines for both the fresh and the embedded material were approximately 6 per cent. There was a good correlation between DNA ploidy determined from fresh and embedded material, respectively; there was also a close correlation between the fractions of S-phase cells estimated from fresh and embedded tumours. It was also possible to cut out small histologically defined lesions, such as carcinoma in situ of the breast from thick paraffin sections and obtain DNA histograms with high resolution.

Juvenile laryngeal papilloma: histologic and photometric evaluation of atypia

Juvenile papillomas are the most common proliferative laryngeal lesion in children. Atypia may be present but is difficult to interpret owing to the basically benign character of the lesion. A histologic and clinical classification of 23 cases of juvenile laryngeal papillomas was performed following the criteria suggested by Quick and co-workers in 1979 and intended to enable the clinical course to be more accurately predicted. The various histologic types of papillomas were characterized by single-cell microdensitometry. The photometric study verified the increase in the relative width of the proliferative zone with the degree of atypia. Severe atypia was the only histologic type associated with hypertetraploid nuclei. The frequent occurrence of mild atypia was unrelated to the clinical course. The moderate and severe degrees of atypia were more common during periods of relatively frequent operations. Severe atypia was rare but in one patient it heralded the development of invasive carcinoma.

A fast and reliable system for microcomputerized DNA cytofluorometry in tumour pathology

A microcomputerized cytofluorometry system based on a Leitz MPV 3 cytophotometer, and intended for DNA measurements in tumour pathology is described. The system has been equipped with a reference channel for correction of excitation light instability. The importance of the adjustment of the epi-illumination for optimal performance of the reference channel is stressed, and a detailed description is provided. An apparatus variability well below 1% CV is obtained even during periods of marked instability of the arc-lamp. Software for conventional cytofluorometry with which about 200 cells can be measured in 20 min is presented. In addition a measuring technique where cells are not positioned, but are just passed through the excitation light spot is described. Preliminary results on cytocentrifuged specimens of human cancers indicate that this system is at least three times faster than conventional fluorometry. The increased speed of measurements considerably extends the possibilities to evaluate cell proliferation using static cytofluorometry. The measuring capacity of course is dependent upon the quality of the specimen. In well prepared cytocentrifuged specimens 1000 cells have been measured in 35 min.

Cytophotometric characterization of the WHO grades of transitional cell neoplasms

The WHO classification of urothelial bladder tumours is widely used, but does not seem to be entirely satisfactory. The main problem is the unhomogeneous WHO II group, and borderline cases in particular are difficult to evaluate histopathologically. Objective assessment of atypia would allow more reliable correlation between morphology and biological behaviour of the tumours to be made. We describe measurements of atypia in 3 characteristic cases of papillary bladder tumour of each WHO grade I, II, and III using Feulgen-DNA-cytophotometry. The mean optical density and nuclear area is determined in 5 micron thick tissue sections. The optical density and nuclear area for each specimen are plotted in a scatter diagram, and the position and variability of the cluster are evaluated. Cytophotometric characterization resulted in defined groups of WHO-graded tumours, and due to this encouraging result the method will be applied in a more comprehensive study of WHO II carcinomas.

Cytophotometric determination of nuclear size and DNA distribution in different hyperfunctioning thyroid lesions

Nuclear enlargement in hyperfunctioning thyroid lesions which has been found in earlier cytophotometric studies is also one of the criteria in the subjective histological estimation of thyroid function. Histopathological assessment is, however, often unreliable. In the present study stage scanning cytophotometric measurements in Feulgen-stained tissue sections were used to determine the nuclear changes encountered in non-toxic and toxic nodular goitre, and in toxic diffuse goitre. To ensure optimal selection of specimens for measurements autoradiography was used. Specimens of toxic diffuse goitre invariably had enlarged nuclei, but no difference was found between nodules in nontoxic and toxic nodular goitre. In fact, the same nuclear area was found in hot nodules, warm nodules and perinodular tissue in non-toxic nodular goitre, and in hot nodules in toxic nodular goitre. Thus there are lesions with clear-cut clinical, biochemical, and autoradiographic hyperfunction that do not have enlarged nuclei. Against this background it is possible that the nuclear enlargement present in toxic diffuse goitre reflects the disorder in itself and not the hyperfunctioning state. Hyperdiploid cell nuclei were found in all cases of toxic diffuse goitre and in a higher percentage than in the other lesions. It was not possible to distinguish nontoxic and toxic nodular goitre on this basis.

HISTOSCAN: computer program for cytophotometry in tissue sections and its application in the evaluation of nuclear atypia

The grading of nuclear atypia has a great and well recognized value when predicting the malignancy of neoplastic processes. Although the basic criteria for the grading are generally agreed upon, in the individual case, the final judgement is to some extent still a matter of subjectivity, which naturally impairs reproducibility. The present paper describes a method for quantification of variability of nuclear size and Feulgen-stainability. By plotting the mean optical density against the area value in a scatter-diagram, a cluster is obtained, the size of which reflects the degree of nuclear atypia. The measurements are performed in tissue sections using stage scanning cytophotometry. A computer program--HISTOSCAN--has been developed which enables measurements in highly cellular tissues. The system is also insensitive to the influence of light scattering, a factor of importance when measuring in tissue sections. The performance of the program is tested in both imprints and tissue sections.