Nuclear DNA content and prognosis in human breast cancer: a static cytophotometric study

Relationship of DNA ploidy and S-phase fraction to survival after first recurrence of breast cancer

Flow cytometry was performed on frozen specimens from the primary tumour of 184 women with recurrent breast cancer. No significant association was seen between DNA ploidy and the other prognostic factors investigated. Patients with a high S-phase fraction had more often a negative estrogen receptor (ER) status and a short disease-free interval. A shorter survival after disease recurrence was seen both in patients with DNA aneuploid tumours and among those with a high S-phase fraction. Patients with DNA tetraploid tumours showed the longest survival after recurrence. In this subgroup, half of the patients survived more than 3 years after recurrence and the estimated survival rate at 10 years was 17%. In a Cox's regression analysis including 116 patients, site of recurrence, number of positive nodes at time of primary operation, size and ER content of the primary tumour as well as DNA ploidy showed additional prognostic value.

Nuclear DNA content of human breast carcinoma: a comparison of results obtained by microspectrophotometry and flow cytometry of paraffin embedded tissue

This study compares 2 techniques for estimating the nuclear DNA content of tumor cell lines: (i) static cytometry of smears taken from fresh tissue and (ii) flow cytometry of cells extracted from paraffin embedded tissue. Parallel determinations of DNA content, using both techniques, were made on samples of tissue taken from 130 female patients with breast carcinoma. Using a simple classification into diploid and non-diploid groups, the 2 techniques yielded discrepant results in 11% of cases. The most frequent causes of disagreement were (a) the inability of static cytometry to distinguish between a diploid and a near-diploid peak and (b) for flow cytometry, the difficulty of determining whether a minor peak in the tetraploid region represented the G2 peak of a diploid cell line or the G0/G1 peak of a tetraploid cell line. If it is deemed necessary to accurately assess ploidy status, flow cytometry on paraffin embedded tissue, using modern statistical programmes, would seem to be most practical for routine use, but some neoplasms, particularly those with an equivocal ploidy peak in the tetraploid range by this method, will require static cytometry to accurately assess nuclear DNA content. Using this approach, it appears that the disagreement between the 2 techniques would be less than 5%.

Histological grading in breast cancer: interobserver agreement, and relation to other prognostic factors including ploidy

Sections of neoplasms from 76 female patients with primary operable carcinoma of the breast were independently assessed by 2 pathologists for histological features and assigned a grade score. Relative disagreement rates between pathologists were estimated by use of a log-linear model and found to be similar to those reported by many other groups, but higher than that reported by acknowledged experts. Tumor grade was related to nuclear DNA content as measured by static cytometry, inversely related to oestrogen receptor status and provided some additional prognostic information but, in this small series of patients, did not correlate with short-term survival as closely as other prognostic indicators such as ploidy, tumor size or the extent of lymph node involvement. Patients with Grade III tumors had a particularly poor prognosis, however, there were few patients allotted to Grade III (poorly differentiated tumors), and survival differences between Grades I and II were small; in short-term followup, used alone, grading separated out only a small proportion of patients into useful prognostic groups. This preliminary study emphasizes the need for a careful approach to the use of grading of breast carcinomas in the routine histopathology laboratory. Demonstration of higher levels of interobserver agreement, or concordance with experts in the field, will be necessary before our grading can be incorporated into a prognostic index useful for patient management.

Prognostic potential of flow cytometric S-phase and ploidy prospectively determined in primary breast carcinomas

In a prospective study of a consecutive breast cancer series accumulated in the period 1978-82, the S-phase fraction (SPF) and ploidy status were determined by flow cytometry performed on cell nuclei derived from samples of 580 primary tumors. Sixty percent of the tumors were non-diploid. After correction for debris the median SPF values were 7.3% overall, 12% for non-diploid tumors, and 2.9% for diploid tumors (2.6% when nodal subsets N2 and N3 and cases with metastases at presentation were excluded). The SPF values correlated both to tumor size (p = 0.008) and to the number of positive axillary lymph nodes (p = 0.03). At clinical follow-up in 1986, 467 unilateral breast cancer patients who had undergone radical treatment for cure could be evaluated with respect to the prognostic value of both the SPF value and ploidy status. The median duration of follow-up was then 59 months (range 2-90), and the median time-to-recurrence 24 months (range 2-69, n = 137). At follow-up in 1991, 201/467 of the patients had died, the median duration of follow-up being 50 months (range 2-126) for the decreased, and 119 (range 6-148) for the survivors. In multivariate analysis (Cox's proportional hazards models), the strongest independent predictors of distant recurrence-free survival (DRFS) were the number of positive axillary lymph nodes (p less than 0.0001), the debris-corrected SPF value alone (p = 0.003, versus p = 0.05 for uncorrected value), and ploidy status combined with the corrected SPF value (p = 0.0002). When age was taken into account, both the corrected SPF value and the ploidy-SPF combination were predictors of crude survival (p = 0.006 and p = 0.002, respectively). In univariate life-table analysis, the 5-year DRFS rate was 93% in node-negative (N0) cases with an SPF less than 7.3%, as compared to 80% in those with an SPF greater than or equal to 7.3% (p = 0.005). Among node-positive cases, the prognostic value of the SPF was confined to those with 1-3 positive nodes, the 5-year DRFS rate being 68% in cases with an SPF less than 7.3%, as compared to 40% in cases with an SPF greater than or equal to 7.3% (p = 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

A meta-analysis of reported correlations between prognostic factors in breast cancer: does axillary lymph node metastasis represent biology or chronology?

A statistical overview of published results on correlations between various prognostic factors in breast cancer was undertaken. A distinction was made between clinical (or anatomical) prognostic factors--namely, axillary lymph node status and tumour size--and eight different biological prognostic factors. The latter included: tumour grade, oestrogen and progesterone receptor status, thymidine labelling index, DNA ploidy, S-phase fraction, epidermal growth factor receptor expression and c-erbB-2 gene amplification (or overexpression). 139 articles were eligible for review which reported a total of 432 individual correlations. A simple form of meta-analysis was employed: the counting method, in which the number of studies achieving a statistically significant correlation or not were counted. For each possible correlation examined, the proportion of studies showing a statistically significant correlation was calculated and an exact binomial 99% confidence interval determined for that proportion. If the 99% confidence interval included 5% (the proportion of correlations that would be expected to be statistically significant if the null hypothesis was true), it was taken as failing to exclude the null hypothesis of a zero correlation, while if it excluded 5% it was taken as rejecting the null hypothesis of a zero correlation. A broad agreement was found among published reports on the existence of a statistically significant correlation between the various biological prognostic factors in breast cancer. Of the 20 correlations examined, 18 had a 99% confidence interval excluding 5%, thus rejecting the null hypothesis of a zero correlation. On the other hand, a completely different result was obtained when reports on possible correlations between lymph node status and tumour size on the one hand and the eight biological prognostic factors on the other were analysed. Of the 16 correlations examined, 13 had a 99% confidence interval including 5%, failing to reject the null hypothesis of a zero correlation. These observations suggest the hypothesis that the prognostic influence of node status and tumour size cannot be explained by an analysis of the biology of breast cancer; and is compatible with the contention that axillary node status is merely a reflection of the relative chronological age of breast cancer.

The prognostic value of tumor-associated carbohydrate structures correlated with gene amplifications in human breast carcinomas

The effects of cell surface sugar chains combined with certain gene amplifications of breast cancers on the prognosis of patients were studied and the relationships between the sugar chains of cancer cells and amplifications of the proto-oncogenes c-myc, int-2 and c-erb B-2, evaluated. One hundred and fifty three human breast carcinoma tissues were investigated by an immunohistochemical technique using the avidinbiotin-peroxidase method with 1 lectin (HPA; Helix Pomatia) and 4 monoclonal antibodies (B-72-3, St-439, anti-Tn and anti-T). The positive rates of HPA, St-439, B-72-3, anti-Tn and anti-T were 43 per cent (63/153), 52 per cent (80/153), 53 per cent (81/153), 64 per cent (98/153) and 89 per cent (136/153), respectively. Patients whose cancers had positive HPA staining were found to have a lower survival rate than those with negative HPA staining (p less than 0.05), whereas those whose cancers had positive St-439 staining showed a better prognosis than those with negative St-439 staining (p less than 0.01). The positive rate of HPA was related to the gene amplification of c-myc proto-oncogene (p less than 0.01), whereas the negative rate of St-439 was correlated with the gene amplification of c-erb B-2 (p less than 0.01). These data indicate the prognostic value of HPA and St-439 and also the relationships between the gene amplifications and carbohydrate structures in breast cancer cells.

Proliferation and DNA ploidy in malignant breast tumors in relation to early oral contraceptive use and early abortions

In 175 premenopausal breast cancer patients, a history of oral contraceptive (OC) use before 20 years of age was significantly associated with higher tumor cell proliferative activity, as indicated by a higher S-phase fraction (SPF), and a higher fraction of DNA aneuploid tumors, compared with later or never users (P = 0.05 and p = 0.01, respectively). The higher SPF among early OC users was apparent in patients with aneuploid tumors but not in patients with euploid tumors. Abortions (spontaneous or induced) before the first full-term pregnancy also were associated with a higher SPF compared with other young patients with breast cancer (P = 0.03). Adjusting for parity and abortions or OC use, respectively, an early OC use was associated with a 43% higher SPF and early abortions were associated with 49% higher SPF. Younger patients had a higher SPF and a higher frequency of aneuploid tumors, but this was found to be because the users of OC had a lower median age at diagnosis. Among never users, no significant age relationship was seen for SPF or the frequency of aneuploidy. For the DNA analyses there is a selection of patients with breast cancer with larger tumors, and therefore the conclusions drawn in this article may not be generalizable to patients with smaller primary tumors, e.g., cases diagnosed at breast cancer screening. The higher tumor proliferative activity and frequency of aneuploidy in early OC users are in line with previously reported findings of worse prognostic indicators and a worse survival in early users of OC compared with other young women with breast cancer.

DNA ploidy and the expression of tissue-carcinoembryonic antigen in grade III carcinoma of the breast

A series of 50 Stage I and II, Grade III ductal carcinomas of the breast was characterized by DNA flow cytometry and further analyzed with a monoclonal antibody for carcinoembryonic antigen (CEA). The antigen was detected with the indirect immunoperoxidase technique on paraffin sections and on cytologic smears of the cell suspensions that were used for flow cytometric DNA analysis. A significant higher incidence of CEA-positivity in cytologic smears and tissue sections was found in DNA-diploid tumors (13/18 and 12/18, respectively) than in DNA-aneuploid tumors (13/22 and 12/32, respectively) (P less than 0.05 and P less than 0.025, respectively).

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.

Flow cytometric detection of multifocal DNA aneuploid cell populations in mastectomy specimens containing a primary breast carcinoma

DNA flow cytometry was used to study the presence of DNA aneuploid cell populations in macroscopically normal glandular tissue in mastectomy specimens from 30 patients with breast cancer. In the 13 patients with a DNA diploid primary tumor, no DNA aneuploidy could be found in any of the 39 distant specimens assessed. However, DNA aneuploid cell populations were demonstrated in four of the 17 (23%) patients with a primary DNA aneuploid carcinoma and in seven out of 54 (13%) distant tissue samples (P = 0.02). In all cases the DNA index of the DNA aneuploid cells found in the distant samples was identical to that of the primary tumor. The replicate aneuploid DNA indices and histologic controls taken in parallel very strongly suggest that these distant DNA aneuploid cell populations are metastases.

Prognostic value of histologic grade nuclear components of Scarff-Bloom-Richardson (SBR). An improved score modification based on a multivariate analysis of 1262 invasive ductal breast carcinomas

We did a multivariate analysis of 1262 patients with operable, invasive ductal breast carcinoma to assess the prognostic value of the Scarff-Bloom-Richardson (SBR) histologic grading system. Nodal metastasis and SBR were the two most important factors for metastasis-free survival (MFS), P = 10-9 and P = 10-5, respectively, for total study time. In patients who were node negative, the SBR and International Union Against Cancer (UICC) stages were the most important for MFS (P = 4 X 10-4 and P = 0.03). In order to try to improve the SBR prognostic value, we first studied the three components of the SBR separately: ductoglandular differentiation proved the least predictive and nuclear pleomorphism and mitotic index the most predictive. A rearrangement of the two nuclear scores alone produced higher risk values and better risk separation of patient subpopulations than SBR, and eliminated the SBR from the multivariate model. This rearrangement, modified SBR (MSBR), defined five new risk subgroups with statistically different risk ratios for MFS (P = 3 X 10-8). SBR grade II (55% of patients) was separated into three MSBR groups significantly different according to MFS (P = 0.008). In the patients who were node negative, MSBR replaced the SBR and was the most important factor for prediction of relapse of MFS (P less than 0.00001). The MSBR is more accurate and predictive than the standard SBR grade and is particularly useful when the nodal status of the patient is negative or unknown.

Nuclear characteristics as indicators of prognosis in node negative breast cancer patients

Nine clinical, biologic and histologic variables were evaluated for their significance in predicting the metastasis free survival (MFS) and the overall survival (OS) of 650 histologic node negative breast cancer patients. The variables studied were: menopausal status, UICC clinical stage of disease, Scarff-Bloom and Richardson (SBR) grade and its 3 components, estrogen and progesterone receptors, and anatomic tumor size. Multivariate Cox analyses revealed that histologic grade and clinical stage were the only significant prognostic factors for both MFS and OS. In the SBR grading system, grades I and III clearly have defined those patients with low and high risk for relapse, respectively. However, it is well known that more than 50% of the patients fall into the intermediate risk category, grade II, which provides essentially no useful prognostic information for those patients. To improve the assignment of patients to specific risk groups, a modified grade (MSBR), with five categories ordered according to the degree of malignancy, has been built from the nuclear pleomorphism and the mitotic index of the SBR grade. In combination with clinical stage, MSBR was found to be a prognostic indicator with high discriminatory power and caused the SBR grade to lose its significance. The first three categories of this MSBR may be gathered to designate low risk patients, whereas the last two categories, once combined, contain all the SBR grade III plus 57% of the SBR grade II tumors, and reliably identify high risk node negative patients. We suggest that a systemic adjuvant therapy should be discussed in this high risk group.

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.

Flow cytometry DNA ploidy and number of cell populations in the primary breast cancer and their correlation to the prognosis

In a prospective study on 516 breast cancer patients flow cytometry DNA ploidy and number of cell populations (defined as number of DNA stem lines) detected in the primary tumor were evaluated for prognostic purposes. The median follow-up time was about 5 years. In the 241 node negative cases, those patients with three or more cell populations had the worst prognosis, with a distant recurrence-free survival rate of about 60% at five years compared to 90% in cases with only one cell population detected in the primary tumor. The number of tumor involved axillary lymph nodes was the outstanding prognostic indicator which was confirmed in 275 node positive patients; DNA ploidy and number of cell populations did not give any significant prognostic information in this group of patients.

Non-palpable invasive breast carcinomas from the Stockholm screening project

Sixty-six non-palpable, invasive mammary adenocarcinomas from the Stockholm mammography screening project were studied with respect to histopathology. In 53 of these tumors estrogen receptor (ER) content was estimated and in 30 of them also the DNA distribution pattern. The tumors were predominantly of low or intermediate histological malignancy grade and ER-rich, whereas the distribution of DNA ploidy equalled that found in a non-selected tumor material. Only 2 tumors recurred during follow-up (median 51 months), indicating that non-palpable breast carcinomas represent a prognostically favourable subset in spite of a relatively high proportion of aneuploid tumors.

Prognostic value of nuclear DNA content in breast cancer in relation to tumor size, nodal status, and estrogen receptor content

The prognostic value of nuclear DNA distribution pattern in relation to tumor size, axillary lymph node status, and estrogen receptor (ER) content was studied in 464 patients with primary, operable mammary adenocarcinoma. The median follow-up time was 3 1/2 years. Slide cytophotometric DNA analysis was performed on morphologically identified Feulgen-stained tumor cells. The tumors were classified into four subgroups according to their DNA histogram type. DNA content was significantly related to tumor size and ER level but not to nodal status. When all variables were stimultaneously introduced into Cox's proportional hazards model, tumor size, nodal status, and DNA profile remained as significant predictors of recurrence. Restricting the analysis to node-negative patients, both DNA profile and tumor size showed a significant prognostic value. DNA did not contribute significant prognostic information in node-positive patients. However, the trends in recurrence-free survival were similar to those in the node-negative subgroup: patients with aneuploid tumors tended to fare worse than those with euploid carcinomas.