Flow cytometric DNA content analysis of 185 soft tissue neoplasms indicates that S-phase fraction is a prognostic factor for sarcomas. French Federation of Cancer Centers (FNCLCC) Sarcoma Group

Nuclear DNA-Content in Mesenchymal Lesions in Dogs: Its Value as Marker of Malignancy and Extent of Genomic Instability

DNA-aneuploidy may reflect the malignant nature of mesenchymal proliferations and herald gross genomic instability as a mechanistic factor in tumor genesis. DNA-ploidy and -index were determined by flow cytometry in canine inflammatory or neoplastic mesenchymal tissues and related to clinico-pathological features, biological behavior and p53 gene mutational status. Half of all sarcomas were aneuploid. Benign mesenchymal neoplasms were rarely aneuploid and inflammatory lesions not at all. The aneuploidy rate was comparable to that reported for human sarcomas with significant variation amongst subtypes. DNA-ploidy status in canines lacked a relation with histological grade of malignancy, in contrast to human sarcomas. While aneuploidy was related to the development of metastases in soft tissue sarcomas it was not in osteosarcomas. No relation amongst sarcomas was found between ploidy status and presence of P53 gene mutations. Heterogeneity of the DNA index between primary and metastatic sarcoma sites was present in half of the cases examined. Hypoploidy is more common in canine sarcomas and hyperploid cases have less deviation of the DNA index than human sarcomas. The variation in the presence and extent of aneuploidy amongst sarcoma subtypes indicates variation in genomic instability. This study strengthens the concept of interspecies variation in the evolution of gross chromosomal aberrations during cancer development.

Prognostic value of proliferation in pleomorphic soft tissue sarcomas: a new look at an old measure

Though proliferation has repeatedly shown a prognostic role in sarcomas, it has not reached clinical application. We performed a comprehensive evaluation of the prognostic role of 5 proliferation measures in a large series of soft tissue sarcomas of the extremities and the trunk wall. One hundred ninety-six primary soft tissue sarcomas of the extremities and the trunk wall were subjected to DNA flow cytometry for quantification of S-phase fraction and to immunohistochemical evaluation of Ki-67, Top2a, p21, and p27Kip1. In univariate analysis, positive expression of Ki-67 (hazard ratio = 4.5, CI = 1.6-12.1), Top2a (hazard ratio = 2.2, CI = 1.2-3.5) and high S-phase fraction (hazard ratio = 1.8, CI = 1.2-3.7) significantly correlated with risk for metastasis. When combined with currently used prognostic factors, Ki-67, S-phase fraction and Top2a fraction contributed to refined identification of prognostic risk groups. Proliferation, as assessed by expression of Ki-67 and Top2a and evaluation of S-phase fraction and applied to statistical decision-tree models, provides prognostic information in soft tissue sarcomas of the extremity and trunk wall. Though proliferation contributes independently to currently applied prognosticators, its role is particularly strong when few other factors are available, which suggests a role in preoperative decision-making related to identification of high-risk individuals who would benefit from neoadjuvant therapy.

The clinical value of flow cytometric DNA content analysis in patients with soft tissue sarcomas

Purpose. The purpose of this study was to evaluate: (1) the correlation between grade and ploidy or S-phase fraction (SPF), (2) the prognostic value of DNA flow cytometric study in soft tissue sarcomas.

Patients /Methods. In all, 47 tissue samples from soft tissue sarcoma patients, surgically treated in the same center, were included. Flow cytometric analyses were performed according to a modified version of the original method of Hedley et al.

Results. DNA ploidy status could be determined in 44 samples out of 47 (success rate 94%). Of these 44, S-phase fraction could be calculated in 34 samples (77%). In the study group as a whole, aneuploidy was significantly correlated with high grade. Survival analyses were carried out in 21 patients with soft tissue sarcoma, all surgically treated in the same center, without chemotherapy or radiotherapy. In univariate analyses, DNA ploidy was found to be a significant factor for overall survival (OAS) and metastasis-free survival MFS. Mean OAS for aneuploid tumors and diploid tumors were 35 and 65 months (p=0.034), and mean MFS 23 and 61 months, respectively (p=0.005) .

Discussion.There is a relation between histological grade and ploidy in soft tissue sarcomas. It appears that low-grade tumors are generally diploid, whereas high-grade tumors tend to be aneuploid. In a subgroup of patients treated only with surgery, DNA ploidy was found to be an important factor for predicting OAS and MFS.

Prognostic Value of CD40 in Adult Soft Tissue Sarcomas

PURPOSE

The purpose is to evaluate the expression of CD40, a membrane protein predominantly expressed on B cells, dendritic cells, and macrophages, in a series of adult soft tissue sarcomas and to test its possible prognostic value.

EXPERIMENTAL DESIGN

CD40 expression was studied by immunohistochemistry. Correlations with other baseline characteristics of patients and tumors were analyzed with chi(2) test. The prognostic value was studied with univariable and multivariable analysis adjusted by age, sex, tumor size, grade, location, and distant metastases.

RESULTS

Eighty-two patients, between January 1994 and May 2001, were analyzed. Membrane or cytoplasmic staining for CD40 protein was absent in 30% of the tumors but present in <10% of cells in 22 (27%), in 10% to 50% in 23 (28%), and in >50% of cells in 12 (15%) tumors. There was no correlation between CD40 expression and age, sex, size, grade, and location of the primary tumor and distant metastases. With 61 patients (74.4%) progressed and 31 (37.8%) dead, CD40 expression was a significant prognostic factor for disease-free and overall survival at univariable and multivariable analysis. Patients with tumors expressing CD40 in >50% of cells had a dramatically unfavorable prognosis with median disease-free and overall survival of 7 and 17 months, respectively, and hazard ratios of relapse and death as compared with patients with CD40-negative tumors of 2.89 (95% confidence interval: 1.26-6.60) and 6.92 (95% confidence interval: 2.18-22.0), respectively.

CONCLUSIONS

These data suggest that expression of CD40 protein in >50% of cells might indicate an unfavorable prognosis in adult soft tissue sarcomas.

Flow-Cytometric DNA Analysis in Cutaneous Fibrohistiocytic Tumors

BACKGROUND

Fibrohistiocytic tumors are rare skin tumors. There are many kinds of fibrohistiocytic tumors. It is often difficult to differentiate dermatofibrosarcoma protuberans (DFSP) and malignant fibrous histiocytoma (MFH) from dermatofibroma (DF) and other benign tumors.

OBJECTIVE

In this study, the possible usefulness of DNA ploidy for the differentiation was studied.

METHODS

Five MFH, 9 DFSP, 3 DF, 2 lipofibromas and 2 scars were studied for DNA ploidy using a flow cytometer.

RESULTS

All the 7 benign tumors showed a diploid pattern. Of 14 malignant fibrohistiocytic tumors, 8 cases (57.1%) showed an aneuploid and 6 a diploid pattern. Two of 5 MFH (40.0%) and 6 of 9 DFSP (66.7%) showed an aneuploid pattern. These results showed that fibrohistiocytic tumors with an aneuploid pattern are malignant, though those with a diploid pattern may be benign or malignant.

CONCLUSION

Analysis of DNA ploidy using flow cytometry was concluded to be useful for the differentiation of malignant fibrohistiocytic tumors from benign ones.

Prognostic factors in soft tissue sarcomas: a study of 395 patients

AIMS

The aim of this study was to report prognostic factors, end-points of local recurrence, distant recurrence, post-metastasis survival, and overall survival in a cohort of patients with soft tissue sarcomas.

METHODS

We analysed a database of 395 patients affected by primary soft tissue sarcomas of various primary sites, treated and followed up at the Centro di Riferimento Oncologico, Aviano, Italy from January 1985 to January 1997.

RESULTS

Grade, size, stage, surgical margins, distant metastasis, age, sex, performance status, and haemoglobin value were significant for overall survival. Histology, grade, stage, and surgical margins were significant for local recurrence. Grade, size, and stage, were significant for distant recurrence; and surgical margin was significant variable for post-metastasis survival.

CONCLUSIONS

Grade, size, and TNM stage (UICC/AJCC) have stronger prognostic significance for overall survival and distant recurrence than for local relapse. Positive surgical margins are the main predictors for local relapse. Age was the most consistent adverse independent prognostic factor for survival.

The adhesion molecule CD44v6 is associated with a high risk for local recurrence in adult soft tissue sarcomas

In many malignant diseases the expression levels of CD44 and its splice variant v6 (CD44v6) have been associated with the prognosis. The purpose of this study was to investigate the clinical significance of CD44 in adult soft tissue sarcomas (STS). 133 STS patients with a limb or superficial trunk tumour treated at the Helsinki University Central Hospital in 1987-1993 with a median follow-up time of 68 months were included in this study. The expression of CD44 and CD44v6 was determined immunohistochemically on paraffin-embedded tumour samples. 95% of the tumours expressed CD44 and CD44v6 was detected in 57%. Strong CD44 expression was associated with low grade (P = 0.04) and small tumour size (P = 0.02). In diploid tumours the CD44 expression was correlated with low S-phase fraction (P = 0.001). High expression of both, CD44 in general as well as that of CD44v6, predicted a higher risk for local recurrence (CD44: P = 0.01 and CD44v6: P = 0.05). Low CD44v6 content of the primary tumour correlated with poor survival (P = 0.02). Determining the expression of CD44 or CD44v6 in a primary STS could be a valuable tool for selecting the group of patients who might benefit from intensified local tumour treatment.

Light scattering from cells: the contribution of the nucleus and the effects of proliferative status

As part of our ongoing efforts to understand the fundamental nature of light scattering from cells and tissues, we present data on elastic light scattering from isolated mammalian tumor cells and nuclei. The contribution of scattering from internal structures and in particular from the nuclei was compared to scattering from whole cells. Roughly 55% of the elastic light scattering at high-angles (> 40 degrees) comes from intracellular structures. An upper limit of 40% on the fractional contribution of nuclei to scattering from cells in tissue was determined. Using cell suspensions isolated from monolayer cultures at different stages of growth, we have also found that scattering at angles greater than about 110 degrees was correlated with the DNA content of the cells. Based on model calculations and the relative size difference of nuclei from cells in different stages of growth, we argue that this difference in scattering results from changes in the internal structures of the nucleus. This interpretation is consistent with our estimate of 0.2 micron as the mean size of the scattering centers in cells. Additionally, we find that while scattering from the nucleus accounts for a majority of internal scattering, a significant portion must result from scattering off of cytoplasmic structures such as mitochondria.

Dermatofibrosarcoma protuberans: an analysis of proliferative activity, DNA flow cytometry and p53 overexpression with emphasis on its progression

The aim of this study is to evaluate the degree and spectrum of malignancy of dermatofibrosarcoma protuberans (DFSP) in the aspect of proliferative activity, flow cytometric DNA analysis, and p53 immunoreactivity. Twenty-three tumors from 19 cases of DFSP including three cases of DFSP with fibrosarcomatous areas (DFSP-FS) were studied in comparison with its allied fibrohistiocytic tumors; that is, dermatofibroma (DF; 46 cases), fibrosarcoma (FS; four cases), and malignant fibrous histiocytoma (MFH; 11 cases). MIB-1 labeling index (LI) of DFSP was significantly higher than that of DF and was lower than those of FS and of MFH. In ordinary DFSP, the recurrent tumors exhibited significantly higher MIB-1 LI than that of the primary tumors, whereas the primary tumors showed almost the same proliferative activity of DF. DFSP-FS tended to have a higher proliferative activity than DFSP without FS-area (ordinary DFSP). In five of 19 cases of DFSP, aneuploidy (near-diploidy) was found in four recurrent and one primary tumors. Immunohistochemical p53 overexpression was found in three of 19 cases of DFSP which also showed higher proliferative activity and aneuploidy. All cases of DF were immunohistochemically negative for p53, but most of the cases of FS and MFH were positive. Although DFSP has been classified in a category of fibrohistiocytic tumor of intermediate malignancy, the recurrent DFSP, DFSP-FS, and DFSP with aneuploidy and/or p53 overexpression could be a subgroup of DFSP with more aggressive clinical behavior than ordinary primary ones.

Prognostic significance of a novel proliferation marker, anti-repp 86, for endometrial carcinoma: a multivariate study

Traditional prognostic factors often fail to identify a subgroup of endometrial carcinoma (EC) patients with an apparently paradoxical poor outcome. We therefore analyzed tumor cell proliferation immunohistochemically in a series of 164 endometrial carcinomas (EC) and compared its prognostic impact with that of the standard prognostic factors patient age, FIGO stage, FIGO grading, and histopathologic subtype. In addition to the established proliferation markers Ki-S5 (Ki-67) and KiS4 (topoisomerase IIalpha), we used a novel monoclonal antibody (MAb), anti-repp 86, which binds to a recently described proliferation-specific protein (p86) expressed exclusively in the S, G2, and M phases of the cell cycle. anti-repp 86, Ki-S4, and Ki-S5 immunoreactive labeling indices (LI) correlated significantly with FIGO stage, FIGO grade, and myometrial invasion, but not with histopathologic subtype. By univariate analysis, conventional prognostic factors and proliferation indices were all predictive of disease-related mortality. A multivariate Cox regression analysis selected anti-repp 86 LI (P = .002), FIGO stage (P = .02), and histopathologic type as significant prognosticators of recurrence; anti-repp 86 LI (P = .001) and histopathologic type (P = .0106) also emerged as relevant predictors of mortality. A hierarchical forward regression model with the conventional prognosticators entered first and with anti-repp 86 entered next showed that anti-repp 86 and histopathologic subtype were the superior independent prognostic indicators for an increased risk of recurrence and cancer-related death. We conclude that the evaluation of anti-repp 86 immunostaining is an easily performable and exceptionally reliable method for identifying EC patients with adverse prognosis.

Soft tissue sarcoma in adults

Soft tissue sarcomas are a heterogeneous group of tumors, consisting of numerous histiotypes that all share a putative common mesenchymal origin. Although prognosis of these tumors is determined by clinical parameters (size, location, and resection margin status) and pathologic features (mitotic activity and necrosis), the histologic subtype has never been shown to be a consistent independent prognostic factor. Some relevant differences among these histiotypes are emerging, in specific biological parameters such as proliferation indices, in integrin expression profiles, and with regard to drug sensitivity. Several biological factors are considered to be prognostically important. Most attention is directed to regulators of cell-cycle progression. The significance of p53 dysregulation is confirmed by the inhibition of cellular proliferation, both in in-vitro and in in-vivo sarcoma models, after reintroduction of wild type p53. A multidisciplinary approach is essential for the optimal treatment of soft tissue sarcomas. Multimodality treatment has led to a patient-tailored approach with limb-sparing resections integrated with external and/or interstitial irradiation. The value of chemotherapy both in the neoadjuvant and the adjuvant setting, although of critical value in other sarcomas such as Ewing's sarcoma and osteosarcoma, remains to be established for soft tissue sarcomas.

Prognostic factors in retroperitoneal sarcomas: ploidy of DNA as a predictor of clinical outcome

BACKGROUND AND OBJECTIVES

Radical surgery is the best mode of treatment of retroperitoneal sarcomas (RS); however, common recurrences are unpredictable.

METHODS

For the better understanding of outcomes and possibilities of treatment retrospective analysis of different factors, including DNA content, was performed based on 70 patients.

RESULTS

Leiomyosarcoma and liposarcoma were most common histologic types of classified sarcomas. Different kinds of resection were successfully performed in 51 patients (73%) and 35 of their available DNA specimens were analyzed. The actuarial 5- and 10-year survival rates in the resection group were 53% and 40%, respectively, with the median survival of 57 months. Patients with diploid resected tumors had a better 10-year survival rate (58%), than those patients with aneuploid tumors (25%,)--P<0.005. Those patients with low-grade sarcomas had a significantly longer survival than those with high-grade sarcomas (10-year survival rate: 44% compared to 29%). In the univariate analysis, adjuvant therapy, type of histology, type of surgery, location of tumor, and S-phase fraction had no influence on survival. In the multivariate analysis (Cox), only ploidy was an independent prognostic variable. Relative risk of death was over three times higher for aneuploid than for diploid tumors.

CONCLUSION

Tumor ploidy should be analyzed in every case of retroperitoneal sarcoma for better assessment of prognosis and possible indication for adjuvant therapy.

Prognostic implications of various models for calculation of S-phase fraction in 259 patients with soft tissue sarcoma

The S-phase fraction (SPF) in flow cytometric DNA histograms in soft tissue sarcoma (STS) can be calculated in various ways. The traditional planimetric method of Baisch has been shown to be prognostic, but is hampered by a failure rate of around 40%. We therefore tested other models to see if this rate could be decreased with retained prognostic value. In 259 STS of the locomotor system the SPF was calculated according to Baisch and with commercial parametric MultiCycle software using different corrections for background. Using the Baisch model, 159 histograms could be evaluated for SPF. The 5-year metastasis-free survival rate (MFSR) was 0.94 for the low-risk group (defined with SPF), and 0.53 for the high-risk group. In the low-risk group, four of the seven patients who developed metastasis did so after 5 years Using the MultiCycle software, SPF could be calculated in 253 tumours. Depending on type of background correction used, the 5-year MFSR varied between 0.67 and 0.82 for the low-risk group, and between 0.47 and 0.53 for the high-risk group. The late metastasis pattern in the low-risk group was never seen using the MultiCycle software. We conclude that in paraffin archival material, calculation of SPF according to Baisch is preferable in clinical use due to better separation between low-risk and high-risk groups, and also the possibility to identify patients who metastasize late.

Immunologic proliferation marker Ki-S2 as prognostic indicator for lymph node-negative breast cancer

BACKGROUND

Proper treatment of lymph node-negative breast cancer depends on an accurate prognosis. To improve prognostic models for this disease, we evaluated whether an immunohistochemical marker for proliferating cells, Ki-S2 (a monoclonal antibody that binds to a 100-kd nuclear protein expressed in S, G2, and M phases of the cell cycle), is an accurate indicator of prognosis.

METHODS

We studied 371 Swedish women with lymph node-negative breast cancer; the median follow-up time was 95 months. The fraction of tumor cells in S phase was assessed by flow cytometry, and tumor cell proliferation was measured immunohistochemically with the monoclonal antibodies Ki-S2 and Ki-S5 (directed against the nuclear antigen Ki-67). A combined prognostic index was calculated on the basis of the S-phase fraction, progesterone receptor content, and tumor size.

RESULTS

In multivariate analyses that did or did not (263 and 332 observations, respectively) include the S-phase fraction and the combined prognostic index, the Ki-S2 labeling index (percentage of antibody-stained tumor cell nuclei) emerged as the most statistically significant predictor of overall survival, disease-specific survival, and disease-free survival (all two-sided P<.0001). In the risk group defined by a Ki-S2 labeling index of 10% or less, life expectancy was not statistically significantly different from that of age-matched women without breast cancer, whereas the group with a high Ki-S2 labeling index had an increased risk of mortality of up to 20-fold.

CONCLUSIONS

Cellular proliferation is a major determinant of the biologic behavior of breast cancer. Prognosis is apparently best indicated by the percentage of cells in S through M phases of the cell cycle. Measurement of the Ki-S2 labeling index of a tumor sample may improve a clinician's ability to make an accurate prognosis and to identify patients with a low risk of recurrence who may not need adjuvant therapy.

Comparison of the Ki-67 score and S-phase fraction as prognostic variables in soft-tissue sarcoma

Immunohistochemically determined Ki-67 scores and flow cytometrically determined S-phase fractions were successfully evaluated from the primary tumours of 123 patients with soft-tissue sarcoma. All patients had either limb or superficial trunk tumours. Ki-67 score correlated strongly with ploidy, S-phase fraction and grade. Ki-67 did not correlate with the size of the primary tumour. When analysed as a continuous variable, Ki-67 was a stronger predictor of both metastasis-free survival and disease-specific overall survival (P = 0.003 and 0.04 respectively) than was the S-phase fraction (P = 0.06 and 0.07 respectively). We tested the relevance of different cut-point values by dividing the whole material into two parts at every 10% (e.g. 10% of patients vs. the remaining 90%, 20% vs. 80%, etc.). We counted the relative risk and confidence interval at all these cut-off points. Ki-67 had good prognostic discriminating power irrespective of the cut-point value, but S-phase fraction lost its prognostic power at higher cut-point values. In conclusion, we found that Ki-67 is a useful prognostic tool in the treatment of soft-tissue sarcoma patients irrespective of the cut-point value. S-phase fraction can be used at lower cut-point values.