Prognostic value of DNA content in colorectal carcinoma. A flow cytometric study with some methodologic aspects

DNA ploidy status and prognosis in colorectal cancer: a meta-analysis of published data

PURPOSE

In colorectal cancer, the negative effect of aneuploidy has been a controversy for more than 20 years. Studies to determine a survival-deoxyribonucleic acid content relationship have conflicting results. A systematic literature search followed by a meta-analysis of published studies addressing prognostic effect of aneuploidy for patients who underwent surgical treatment of colon and rectal cancer was conducted.

METHODS

The main outcome measure was the five-year overall mortality rate after surgical resection. For the selected studies, we estimated this outcome for three subsets of patients through separate meta-analyses: 1) for all patients with colorectal cancer; 2) only between patients with Stage II colon cancer; and 3) only for studies in which follow-up losses were declared. The presence of publication bias was assessed with a funnel plot for asymmetry.

RESULTS

A total of 5,478 patients with colorectal cancer were represented in 32 studies (Group 1), we estimated a reduction in the five-year overall mortality from 43.2 percent for aneuploid tumors to 29.2 percent for diploid tumors (combined relative risk = 1.44; 95 percent confidence interval = 1.34-1.55; P < 0.001). In addition, 357 patients with Stage II colon cancer (Group 2) extracted from three studies had an absolute reduction of 14.3 percent in five-year overall mortality favoring diploid tumors (combined relative risk = 1.93; 95 percent confidence interval = 1.29-2.89; P = 0.001). Lastly, of 14 studies in which follow-up losses were declared (Group 3), 2,221 patients were represented and a 15.7 percent mortality reduction was measured favoring patients with diploid tumors (combined relative risk = 1.44; 95 percent confidence interval = 1.3-1.61; P < 0.001).

CONCLUSIONS

Patients who undergo an aneuploid colorectal cancer surgical resection have a higher risk of death after five years. This finding may ultimately impact survival of patients with node-negative colon cancer through adjuvant therapy.

DNA index and S-phase fraction in curative resection of colorectal adenocarcinoma: analysis of prognosis and current trends

The DNA index (DI) and S-phase fraction (SPF) have been said to be independent factors in colorectal adenocarcinoma and have a different distribution from the clinicohistologic parameters. This study assesses the real efficacy of DI and SPF for curative resection of colorectal adenocarcinomas with respect to the prognosis and the clinicohistologic parameters. From July 1991 to October 1994 a total of 666 patients underwent curative resection of colorectal adenocarcinoma and DNA flow cytometry in Kaohsiung Chang Gung Memorial Medical Center Hospital, Taiwan. We defined diploid tumors as having a DI of ? 0.9 but <1.1 and a nondiploid tumor as having a DI of <0.9 OR > 1.1. A high SPF was defined as being more than the median value for the total SPF. Altogether, 495 cases (74.32%) had a 5-year cancer-free survival. Tumor stage, DI, tumor location, and tumor morphology were associated with significant cancer-free survival in the univariate analysis (p = 0.0295, <0.001, 0.0357, and <0.001, respectively). After all factors were entered into the multivariate analysis, the independent factors for cancer-free survival were found to be stage, tumor location, and morphology (p < 0.001, 0.012, and 0.044, respectively). In cases distinguished by the DI, diploid tumors had significantly more frequent right colon locations (p <0.001). After cases were separated by the SPF (median value 18.4%), better histology (well differentiated adenocarcinoma) was noted with a low SPF (p = 0.017). No other clinicohistologic parameters had significant differences shown by the DI or SPF. Thus DI and SPF failed to appear as independent factors for 5-year cancer-free survival. The independent factors for curative colorectal adenocarcinoma were tumor stage, location, and morphology. Diploid tumors were located at the right colon more often, and low SPF indicated better histology in the univariate analysis.

Correlation of flow cytometric parameters and transferrin receptors with gallium-67 scintigraphic images in lymphoma patients

The purpose of this study was to determine the correlation of flow cytometric parameters and transferrin receptors with gallium-67 scintigraphic imaging results in Hodgkin's and non-Hodgkin's lymphoma patients. DNA content and cell cycle analyses were performed using flow cytometry and transferrin receptor analysis was carried out by the immunohistochemistry technique in 24 patients aged between 16 and 62 years. All patients underwent gallium-67 scintigraphy, and tumour to background ratios were calculated. The findings were correlated with computed tomography and/or magnetic resonance imaging. A strong relationship was observed between flow cytometry and transferrin receptor expression with gallium-67 tumour scintigraphy [P = 0.005, r = 0.054 and P = 0.038, r = 0.54 (Spearman test), respectively]. The results of this study show that there is a close correlation between each of these modalities and, as they reflect the biological activity of the tumour, together they have a major role in treatment and follow-up.

Smooth muscle tumors of the esophagus: clinicopathological findings in six patients

Preoperatively, it is difficult to discriminate leiomyoma and leiomyosarcoma of the esophagus, which are rare smooth muscle tumors. The objective of this study was to evaluate the clinicopathological findings of this unusual lesion. A search of the surgery archives of the Toyama Prefectural Central Hospital of Pathology revealed six cases of esophageal smooth muscle tumors. Clinicopathological findings were reviewed retrospectively. Only three patients (50%) presented with dysphagia, and the remaining three patients were asymptomatic. These patients underwent surgical excision. Histologically four of the six tumors were leiomyomas, and the other two tumors were leiomyosarcomas. Two tumors were in the upper to middle esophagus, and the remaining four were in the distal esophagus. On endoscopic examination, all tumors were noted to be polypoid. The two leiomyosarcomas measured over 5 cm and the four leiomyomas less than 4 cm. Neither ulceration nor necrosis proved to be of use in discriminating leiomyoma and leiomyosarcoma. The two patients with leiomyosarcoma died of liver metastasis 10 and 22 months after the treatment. Patients with leiomyosarcoma presented with distant metastasis and/or recurrence, with hematogeneous metastasis being the predominant type of recurrence.

DNA ploidy in colorectal cancer, heterogeneity within and between tumors and relation to survival

Flow cytometry was used to study the incidence of aneuploidy and to determine the significance of multiple sampling from colorectal tumors. DNA ploidy pattern has been proposed as a supplementary prognostic marker, but discrepancies in findings are major. DNA clonal heterogeneity, defined as two or more DNA aneuploid stemlines in the same tumor, is well established. However, most studies have been based on only one biopsy from each tumor. In our study multiple biopsies were taken from 163 patients (88 males and 75 females) electively operated for colorectal cancer. Tumor cells were harvested by fine needle aspiration from fresh frozen biopsies sampled at different sites of each tumor. DNA aneuploidy was detected in tumors from 145 patients (89%), and 18 patients (11%) had a solitary DNA diploid cell population. In a 79 month follow-up period 105 patients had died. Statistical analysis showed that distinction between diploidy and aneuploidy did not predict survival. However, grouping subpopulations into DNA diploid plus near diploid (DNA index (DI) 0. 97-1.15), DNA aneuploid with all aneuploid subpopulations in the interval 1.15-2.06, and DNA aneuploid with subpopulations with DI < 0.97 and/or DI > 2.06, showed a significant difference in survival in a Cox multivariate analysis including Dukes' stage P = 0.049 comparing the second group to the first and P = 0.01 comparing the third group to the first. In 21 (13%) patients only one subpopulation was found, 57 (35%) had two, 44 (27%) had three, and 41 (25%) had four or more different subpopulations. The association of DNA ploidy to survival is shown to be dependent on the number of biopsies analysed.

Usefulness of proliferative activity, DNA ploidy pattern and p53 products as diagnostic adjuncts in colorectal adenomas and intramucosal carcinomas

Although numerous studies have assessed the biologic parameters of tumors, measurement of these parameters has had, to date, little impact on histologic diagnosis. Furthermore, analysis of a single parameter is insufficient to evaluate tumor malignant potential. In the present study, cell proliferation, DNA ploidy and p53 product were analyzed to objectify the tumor malignant potential in colorectal adenomas and intramucosal carcinomas. Sixty-one adenomas and 49 intramucosal carcinomas were studied using immunohistochemical analysis of Ki-67 and p53, silver-staining nucleolar organizer region (AgNOR) stain and DNA ploidy in fresh samples. Intramucosal carcinoma exhibited a greater Ki-67-positive rate and AgNOR count than the adenomas, although these parameters varied widely among samples. The incidence of aneuploidy and p53 over-expression in colorectal intramucosal carcinomas was significantly higher than in colorectal adenomas. These results indicate that DNA aneuploidy and p53 accumulation are the most reliable parameters for distinguishing benign and malignant lesions.

NO38 expression and nucleolar counts are correlated with cellular DNA content but not with proliferation parameters in colorectal carcinomas

AIMS

To investigate the expression of nucleolar protein NO38, to determine the numbers of nucleoli per cell, and to examine the relations of these nucleolar parameters to tumour DNA index, total cellular DNA content, S phase fraction, and Ki67 labelling index.

METHODS

36 colorectal tumours and 14 normal mucosas were studied. An anti-NO38 monoclonal antibody, 31A12, and flow cytometric analysis were used to detect expression of NO38 by means of a biotin-streptavidin-FITC (fluorescein isothiocyanate) staining method. Nucleolar counts were determined using fluorescence microscopy. Flow cytometry was used to determine tumour DNA indices and the sizes of the S phase fractions. Ki67 labelling indices were determined from tissue sections stained immunohistochemically with the MIB-1 antibody against the Ki67 nuclear protein.

RESULTS

Generally, tumour cell nucleoli were larger and more irregular in shape compared with nucleoli in normal mucosal cells. DNA aneuploid and diploid tumours expressed 2.8 and 2.1 times more NO38 than normal mucosa. The mean (SD) values for nucleolar counts were higher for the DNA aneuploid tumours (3.81 (0.93)) than the diploid tumours (2.62 (0.38)) and normal mucosa (2.34 (0.37)). NO38 expression and numbers of nucleoli correlated significantly (r = 0.52, p = 0.01). There were, however, no significant correlations between these nucleolar parameters and either the sizes of tumour S phase fractions or Ki67 labelling indices. Cell cycle resolved expression of NO38 in tumours and normal mucosa demonstrated that expression increased approximately in proportion to the DNA content throughout the cell cycle. In aneuploid tumours, NO38 expression was 43% and 98% higher in S and G2 phases, respectively, compared with the G1 phase. Sorting of these populations revealed that the nucleolar count also increased as the DNA content increased but by only 29% and 47% in S and G2, respectively. Apoptotic cells lacked NO38.

CONCLUSIONS

NO38 expression is higher in tumours than in normal mucosa owing to the increased DNA content and larger nucleoli in tumours; expression increases proportionally with DNA content as cells progress through the cell cycle from G1 through S and G2. However, NO38 expression does not correlate with the tumour S phase fraction or Ki67 labelling index and is lost during apoptosis. Also the results suggest that nucleoli grow in size during the cell cycle, which would account for the doubling of NO38 expression from G1 to G2, as the nucleolar count increased by only 47%.

Flow cytometric DNA ploidy and S-phase fraction correlate with histopathologic indicators of tumor behavior in colorectal carcinoma

BACKGROUND

The clinical behavior of colorectal carcinoma is highly variable without reliable predictive biomarkers. Previous reports have shown that flow cytometric DNA analysis may provide valuable prognostic information in these tumors.

PURPOSE AND METHODS

This study evaluates the DNA ploidy and the S-phase fraction (SPF) on frozen samples obtained from 61 patients with colorectal carcinoma by using flow cytometry, and it correlates the data with histopathologic features known to affect disease prognosis. Tumors were classified using the World Health Organization's histologic criteria and were staged according the American Joint Committee on Cancer's classification system. Grade of the neoplasm, vascular invasion, and perineural tumor spread were evaluated in every case.

RESULTS

Fifty-nine percent of tumors were aneuploid and showed statistically significant higher S-phase values than diploid tumors (22.5 vs. 11.2 percent; P < 0.00001). Mean SPF of the whole series was 17.9 (range, 4.2-44.2) percent. A statistically significant association was found between SPF values and histologic grade (P < 0.0016), nodal status (P < 0.0007), distant metastasis (P < 0.0001), tumor stage (P < 0.0001), venous invasion (P < 0.0002), and lymphatic permeation (P < 0.01) but not with perineural growth and infiltration of the neoplasm through the bowel wall (T). DNA ploidy correlated positively with tumor stage (P < 0.03), and the association between aneuploidy and advanced stages of the disease was statistically significant.

CONCLUSIONS

These findings showed that flow cytometric DNA ploidy and SPF, evaluated in fresh samples, are potentially useful parameters to estimate colorectal carcinoma biopathology. Aneuploidy and high replicative neoplastic activity correlated with histopathologic features that are commonly associated with the prognosis of colorectal carcinoma, being SPF-related to disease dissemination and, therefore, an indicator of clinical relevance.

Prognostic value of ploidy, cell proliferation kinetics, and conventional clinicopathologic criteria in patients with colorectal carcinoma: a prospective study

PURPOSE

The aim of this study was to obtain additional biologic determinants that may be of use in segregating into subgroups with different prognosis patients with similarly staged colorectal cancers.

METHODS

Between 1989 and 1991, a prospective study of prognostic factors has been performed in a group of 98 consecutive, unselected patients who underwent curative resections for primary untreated large bowel carcinoma. The fate of all patients is known at three years after operation. Clinical and pathologic data were recorded at the time of presentation and operation, and patients have been the subjects of regular follow-up. Tumor DNA content was determined by flow cytometry, and cell proliferative activity was determined by autoradiography with tritiated thymidine labeling index (LI).

RESULTS

Univariate analysis revealed that the most important predictors of survival (P < 0.001) were the presence of positive lymph nodes, the presence of preoperative complications, Dukes stage, and LI. The multivariate analysis showed that Dukes stage (P < 0.002) and LI (P < 0.0001) were the only factors significantly related to survival. Disease-free survival was influenced significantly by Dukes stage (P < 0.001), LI, according to the classification in the two groups of high and low proliferative activity, respectively, (P < 0.0001), LI, calculated as a continuous variable (P < 0.0002), and the presence of lymph node metastases (P < 0.003). Outcome (favorable/unfavorable) was influenced significantly by Dukes stage (P < 0.0001) and LI (P < 0.0001). Concordance for each patient between Dukes stage and outcome was 73.1 percent and between LI, calculated as a continuous variable, and outcome was 74.1 percent. If, on the other hand, Dukes stage and LI are used together, concordance with outcome reaches 89.2 percent.

CONCLUSION

We can conclude that, from a practical point of view, LI is an essential factor that must be combined with pathologic variables for a better prediction of patient outcome.

DNA flow-cytometric analysis in colorectal cancer: a comparison of metastasizing and non-metastasizing tumours

The most common cause of death in patients with colorectal cancer is metastatic liver disease. In order to identify patients at a high risk of developing hepatic secondaries from colorectal cancers, DNA content was measured in metastasizing colorectal primaries (Group I, n = 32) as well as in their subsequently resected liver secondaries and in sections of non-metastasizing colorectal cancers (Group II, n = 25). A modified interpretation system involving both a DNA index and percentage of cycling cells (those in S and G2 + M phases) was developed. DNA content was measured in paraffin-embedded sections by flow cytometry using internal controls (human peripheral blood mononuclear cells) and non-malignant tissue controls (19 patients with diverticular disease). In Group I there were significantly more tumours with both abnormal ploidy (aneuploid or abnormal tetraploid peak) and > 15% cycling cells compared with Group II (Chi-squared; P = 0.034). The combination of abnormal ploidy and > 15% cycling cells was superior to Dukes' classification for identifying metastasizing tumours (Logistic Regression; P = 0.047). However, it was not possible to discriminate between the two groups using either DNA ploidy or the percentage of cycling cells alone. The metastasizing colorectal cancers exhibited similar DNA ploidy characteristics and had a similar percentage of cycling cells compared with their liver metastases. These results suggest that tumour DNA ploidy plus the percentage of cycling cells may predict the development of liver metastases and thus survival in patients with colorectal cancer.

Nuclear DNA content and pathology in radically treated pancreatic carcinoma. The prognostic significance of DNA ploidy, histology and nuclear grade

BACKGROUND

Nuclear DNA content and pathology are considered to be prognostically relevant in several solid tumors, but controversial findings have emerged in pancreatic carcinoma (PC). Histopathology and DNA ploidy were each correlated with survival in radically treated PC to ascertain the hierarchy of their prognostic significance.

METHODS

DNA ploidy was assessed by flow cytometry (FC) in neoplastic tissue samples from 60 patients with PC who were followed until death. Representative neoplastic areas were obtained by microdissection from archival paraffin embedded material (excluding any carcinoma with a coefficient of variation of the G0/G1 peak higher than 8%). Histologic data and FC patterns were related to prognostic behavior using univariate multivariate statistical analysis.

RESULTS

Aneuploid cancers were detected in 39 of 60 patients. Univariate analysis showed that histologic grade, nuclear grade, and ploidy were significantly related to prognosis. On multivariate analysis, only histologic grade and DNA ploidy (diploid vs. aneuploid) were significant with significant interaction.

CONCLUSIONS

The prognostic value of pathology and ploidy was demonstrated in patients treated radically for PC. As in other tumors characterized by a short survival, the clinical usefulness of any prognostic parameters is somewhat limited. However, the significant relationship between prognosis and DNA ploidy might be of interest in a cost-benefit analysis for selecting patients in whom an attempt at radical surgical treatment or adjunctive chemotherapy may be justified.

Prognostic evaluation of DNA flow cytometric and histopathologic parameters of colorectal cancer

BACKGROUND

The clinical value of DNA flow cytometry of colorectal cancer is unclear. The purpose of this retrospective study was to evaluate the relationship between tumor flow cytometry, histopathologic parameters, and survival.

METHODS

Flow cytometry was performed on paraffin embedded specimens from 653 patients who had surgery from 1980 to 1983.

RESULTS

Aneuploidy was associated with distal tumor, perineural invasion, desmoplastic reaction, and failure to secrete mucin. TNM Stage I tumors were more frequently diploid than were more advanced tumors (71% vs. 41%). An abnormal DNA content had a marginal impact on survival as evaluated by univariate analysis (69% vs. 61% 10-year survival rate, P = 0.06). Multivariate analysis revealed that significant predictors of outcome were lymph node metastasis (95% confidence interval of relative risks of death from recurrent disease, 1.50-2.92), rectal cancer (1.22-2.19), absence of lymphocytic infiltration (1.20-2.17), invasion through bowel wall (1.17-3.13), lymphatic vessel invasion outside bowel wall (1.05-2.69), perineural invasion (1.15-3.19), and male gender (1.00-1.79).

CONCLUSIONS

These findings suggest that ploidy is associated with some histopathologic parameters, but flow cytometry does not correlate with long term survival of patients with colorectal carcinoma.

A search for prognostic factors in cancer of the pancreatic head: the significance of the DNA ploidy pattern

Using flow cytometry after the nuclear isolation and staining of tissue specimens, the significance of the DNA ploidy pattern as a prognostic factor in cancers of the head of the pancreas has been evaluated in 33 patients who underwent a pancreatic cancer resection. In addition to the DNA ploidy pattern, the size of the tumour, regional lymph node involvement, the tumour's histopathological grade and the results of a curative resection were also evaluated as prognostic factors. The results of a univariate analysis revealed that the survival rate was significantly higher for patients with a diploid tumour (n = 20) than for patients with an aneuploid tumour (n = 13) (P < 0.001). Furthermore, survival rates were significantly better for patients with a T1 tumour than with a T2 or T3 tumour (P < 0.001), for patients without positive lymph node involvement than for those with positive lymph nodes (P < 0.001), for patients with well-differentiated adenocarcinomas (G1) than for those with moderately differentiated (G2) or poorly differentiated (G3) adenocarcinomas, and for patients who underwent a curative resection than for those who underwent a non-curative resection (P < 0.005). A multivariate analysis revealed significant prognostic differences in the DNA ploidy pattern (P < 0.001), the frequency of a curative resection (P < 0.001), regional lymph node involvement (P < 0.05), and in the tumour's histopathological grading (P < 0.05) but not its size. This study has found the DNA ploidy pattern to be the most significant prognostic factor (chi 2 value: 38.1).

Bivariate cytokeratin/DNA flow cytometric analysis of paraffin-embedded samples from colorectal carcinomas

Admixture of normal and neoplastic cells is a serious problem in the evaluation of tumor cell kinetic parameters by flow cytometry, in particular for DNA diploid tumors. The admixture of non-neoplastic cells, such as stromal cells and inflammatory cells, can disturb the estimation of the proliferative tumor fraction. This problem has been addressed in fresh tumor samples by applying bivariate flow cytometric analyses for DNA and cytokeratin. We have adapted this approach for formalin-fixed and paraffin-embedded tissue samples of colorectal carcinomas. After preparation of a single cell suspension from paraffin blocks by means of an enzymatic digestion step, the cells of epithelial origin were selectively stained with a panel of subtype specific cytokeratin antibodies. DNA analysis could thus be performed on the cytokeratin-positive cells. The proliferative fractions of the paraffin-embedded samples could be compared with those of the fresh tissue samples and a very good correlation was seen between DNA indices from fresh and paraffin-embedded material. As expected, after gating on the cytokeratin-positive cells an enrichment of the S-phase fraction was seen compared with the ungated cell population. However, this enrichment was more pronounced in the cell suspensions derived from the paraffin-embedded part of the tumor compared with the fresh disaggregated, ethanol-fixed part of the tumor.

DNA index and S phase fraction in uveal malignant melanomas

AIMS

To predict 5 year survival in patients with uveal malignant melanomas DNA indices were studied.

METHODS

Using 45 paraffin embedded uveal malignant melanomas, the DNA index and S phase fraction of each tumour were the predictor variables recorded.

RESULTS

Using the Cox proportional hazards model, aneuploid tumours and tumours which had an S phase fraction greater than 4% were significant predictors of early death. In order to demonstrate a biological gradient between a larger DNA index and shorter survival time, linear regression and transformed linear regression models were used. However, no such gradient could be demonstrated.

CONCLUSION

Although this study shows promise for the use of DNA studies in the prognosis of uveal malignant melanoma, the exact role of these techniques remains to be determined.

Correlation of DNA content between endoscopic biopsy and surgically resected specimens in gastric and colorectal cancer

To investigate DNA heterogeneity and the consistency of DNA content between endoscopic biopsy and the corresponding resected specimens, the DNA content of 749 different samples from 30 gastric and 30 colorectal cancers was analyzed and the results were compared with those obtained from endoscopic biopsy specimens. The incidence of DNA heterogeneity was 33% in patients with gastric cancer and 40% in those with colorectal cancer. Most of the cases of heterogeneity were caused by differences in DNA indices in aneuploidy. The consistency of DNA ploidy pattern between endoscopic biopsies and the corresponding resected specimens was 100% in both gastric and colorectal cancer, while the consistency in the DNA index of aneuploid tumors was approximately 90%. From these results, it seems possible that analysis of the DNA content of a biopsy specimen could provide an adequate measure of the DNA content of the corresponding resected specimen.

Flow cytometric analysis of DNA heterogeneity in superficial carcinoma of the esophagus

BACKGROUND

There are few studies of flow cytometric analysis for DNA heterogeneity of patients with superficial carcinoma of the esophagus limited to the epithelium or superficially invading the lamina propria or submucosa.

METHODS

Flow cytometric analysis of cellular DNA content was performed on superficial carcinomas of the esophagus using paraffin embedded blocks of the surgically resected specimens from 56 patients. To evaluate the intratumoral DNA heterogeneity, a total of 141 samples of the 56 tumors were analyzed, depending upon the tumor size.

RESULTS

One or two of the samples was available from 18 of 19 patients with tumors 2 cm or less in greatest dimension, whereas more than three of the samples were available from 22 of 37 patients with tumors 2.1 cm or greater in dimension (P < 0.003). Of 56 tumors, 40 (71.4%) exhibited DNA aneuploidy; DNA heterogeneity was found in 26 tumors (46.4%). The remaining 16 tumors exhibited DNA diploidy. Two of the five tumors that were limited to the epithelium had DNA heterogeneity. The mean dimension of the tumors with DNA heterogeneity was significantly greater (5.8 +/- 2.8 cm) than those exhibiting DNA diploidy (2.3 +/- 1.1 cm) and DNA aneuploidy without heterogeneity (2.9 +/- 2.4 cm). Recurrences after esophagectomy were detected in 6 of the 56 patients; the DNA ploidy pattern of these six patients exhibited DNA heterogeneity.

CONCLUSION

The incidence of DNA heterogeneity increases as tumor size increases and is associated with an increased risk of tumor recurrence after esophagectomy in patients with superficial carcinoma of the esophagus.

Variability of neoplastic parameters in colon tumours, and its significance in diagnostic practice

We have reviewed the value of individual variability in the reaction of tissues to treatment with carcinogens, and the manifestation of this variability in different morphological (histological, morphometric, and ultrastructural), histochemical and immunohistochemical parameters generated in tumorous tissues. Moreover, we also reviewed data in the literature on individual variability in the manifestation of some biochemical and immunochemical markers which are accumulated in the serum of tumour-bearing patients and which are characteristic for the different phases of tumourigenesis. The high variability of different tumorous parameters suggests that none can be utilized alone as a conclusive marker of neoplasia and that only their combined use can give objective information. We also reviewed the impact of this variability in the evaluation of various pathological methods to detect different stages of neoplastic transformation in the colon. It has been concluded that none of the present approaches can be absolutely conclusive and without false results, and that objective information regarding early cancerous changes may be obtained only by use of combined analyses utilizing several laboratory methods. The diagnostic procedures should be based on the complex utilization of all appropriate methods using the quantitative interpretation of the obtained data. Multivariate analysis of many parameters should be very effective for the prediction of therapeutic results.

Prospective analysis of colorectal carcinoma. Determination of an age-site and stage relationship and the correlation of DNA index with clinicopathologic parameters

PURPOSE

A prospective study of colorectal cancer (1987-1991) using flow cytometry was performed to determine the relationship of age with DNA index (DNA-I), sites of disease, Dukes stage, grade, and survival.

METHODS

The flow cytometry was performed on 138 fresh, unfixed, surgical specimens using 4',6'-diamidino-2-phenylindole, a DNA fluorochrome.

RESULTS

The mean age was 66.9 (42.8 percent > or = 70; range, 22-92; median, 68) years, and 48.6 percent were female. The patients' stages were (in percent): A, 4.4; B, 53.0; C, 38.2; D, 4.4. Tumor grades of differentiation (in percent) were well, 14.4; moderate, 68.9; poor, 16.7; and sites (in percent) were: rectum, 19.6; sigmoid/left, 50.7; transverse/right, 29.0. Aneuploidy (DNA-I not equal to 1.0; CV, 3.5 percent) was found in 58.8 percent. Age (by decade of presentation) was compared with site and Dukes stage. Older patients had more transverse/right-sided lesions (P = 0.003). Patients with Dukes C and D tumors had a lower age (by decade of presentation) than patients with B2 lesions (P = 0.03). Age was not related to DNA-I or grade or DNA-I with sex, grade, site, stage, or survival (P > 0.05).

CONCLUSIONS

This prospective study suggests that colorectal cancer tends to present at an earlier stage and in the more proximal colon in the older population. Because right-sided lesions are beyond the reach of sigmoidoscopy, these findings have prognostic and screening implications.

Comparison of double and single parameters in DNA analysis for staging and as a prognostic indicator in patients with colon and rectal carcinoma

PURPOSE

This study was designed to determine the reliability of DNA analysis in predicting outcome of patients with colorectal carcinoma and compare the prognostic efficacy of DNA analysis using two parameters vs. a single parameter.

METHODS

Two hundred forty-eight patients with colon and rectal carcinoma were entered in the study over a period of 84 months. Thirty-one percent of carcinomas were found in the rectum. A total of 23.6 percent of cancers were found in the sigmoid colon. Majority of the patients were 60 years or older. Male to female ratio was equal. The colon bearing carcinoma was sent in a fresh state after resection for flow cytometry and DNA analysis. In this study, analysis was made, comparing two parameters (aneuploidy and S-phase fraction over 20 percent) with single parameters (aneuploidy) for staging and as a prognostic indicator in patients with colon and rectal carcinoma.

RESULTS

The combined presence of aneuploidy and S-phase fraction over 20 indicated a poorer prognosis in patients with colon and rectal carcinoma. The prediction of patient outcome was more accurate with DNA analysis using two parameters than using a single parameter alone (P value = 0.00003).

CONCLUSION

In our analysis, the odds of survival are over 3.7 times greater for aneuploidy than aneuploidy plus S-phase fraction over 20 percent.

A solid and cystic tumor of the pancreas in a 10-year-old girl: report of a case and review of the literature

We report herein the unusual case of a 10-year-old girl in whom a neoplasm developed in the head of the pancreas. Complete extirpation of the tumor was performed, which was histologically classified as a "solid and cystic tumor of the pancreas." Postoperative DNA analysis revealed a diploid pattern. The patient remains well with no sign of tumor recurrence 2 years after her operation. Thus, complete tumor extirpation without pancreatectomy is recommended for pediatric patients when there is no direct invasion to the adjacent organs or distant tumor metastasis.

Quantitative DNA measurement by flow cytometry and image analysis of human nonseminomatous germ cell testicular tumors

Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30-40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M + S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only.

Application of dual parameter analysis in flow cytometric DNA measurements of paraffin-embedded samples

In a comparison of flow cytometric DNA measurements on fresh and paraffin-embedded material from primary squamous cell carcinomas of the head and neck region, we discovered that previously undetected aneuploid clones could be detected by dual parameter analysis of cytokeratin and DNA applied to disintegrated cells from paraffin sections. Using this new approach the correlation coefficient between DNA-indices from fresh and paraffin-embedded material increased from 0.423 to 0.904.

DNA or cell kinetics flow cytometry analysis of 33 small gastrointestinal cancers treated by photodynamic therapy

BACKGROUND

Photodynamic therapy (PDT) mediated by hematoporphyrin derivative (HPD) is a new treatment for cancers of small volume undergoing Phase II or III clinical trials in various medical fields. However, there is a lack of prognostic criteria of efficacy as in other cancer treatment.

METHODS

Cell DNA content or cell kinetics throughout the cell cycle were analyzed by flow cytometry and propidium iodide staining before and after HPD-PDT in 33 patients with Tis or T1 cancers of the gastrointestinal tract. The authors compared results in near-diploid cancers with those obtained in normal corresponding tissue.

RESULTS

Complete local tumor destruction and negative histologic findings (complete response [CR]) were observed in 17 of 33 patients during a period averaging 15.7 months. Flow cytometry DNA analysis was feasible in 32 patients. Aneuploidy, found in 15 of the 32 indicated a poor prognosis because 5 of 15 patients with aneuploid tumors were classified as having CR, compared with 12 of 17 patients with near-diploid tumors (P < 0.05). Changes in ploidy after PDT in 11 patients consisted of a reduction in the number of aneuploid peaks in 8 patients and the appearance of one aneuploid peak in 3 patients. Percentages of cells in SG2M phase in near-diploid tumors differed from those observed in control subjects for adenocarcinomas, and there was no significant decrease after HPD-PDT. There was no correlation between the decrease of SG2M cells and the response to HPD-PDT.

CONCLUSION

Results obtained with PDT in this series of patients confirm previously published findings. Changes occurring in the ploidy of PDT-treated patients demonstrate that PDT acts directly on cancer cells in humans and not only on tumor vasculature. However, response to PDT varies from one cell population to another. The appearance of aneuploid populations after PDT suggests that destruction of sensitive cell populations allows the growth of aneuploid clones that initially are not detectable by flow cytometry.

Factors influencing survival after resection of pancreatic cancer. A DNA analysis and a histomorphologic study

BACKGROUND

The influence of DNA content on prognosis in stomach cancer has been investigated rarely, and the results are controversial.

METHOD

The prognostic relevance of the DNA content and histomorphologic parameters was evaluated in 41 patients after resection of pancreatic cancer.

RESULTS

In the univariate analysis, the DNA content, tumor size, lymph node status, tumor stage, nuclear grade, and type of resection had a statistically significant influence on the prognosis. No association was found between the DNA content and the histomorphologic features. Apart from the operative procedure, the DNA content was the strongest indicator of prognosis in the multivariate analysis.

CONCLUSIONS

Further investigations are necessary to find out if DNA analysis can be performed preoperatively on material obtained by fine-needle aspiration.

Prognostic value of DNA analysis in colorectal carcinoma

BACKGROUND

Reported experiences regarding the prognostic significance of DNA content in colorectal carcinoma have been a matter of controversy.

METHODS

DNA analysis with image cytometry was performed in 137 patients with colorectal cancer. Only patients who had resection without tumor residual and who did not die postoperatively as a consequence of the operation were entered in the study. At the time of DNA analysis, neither the histomorphologic data nor the relapse-free survival time of the patients were known.

RESULTS

In this investigation the DNA content of tumor cells had no univariate or multivariate influence on the relapse-free survival time. The prognosis was dependent on the tumor localization, depth of tumor infiltration, lymph node metastasis, and grade.

CONCLUSIONS

DNA content provides no additional prognostic information in colorectal carcinoma.

DNA densitometry of colorectal cancer

DNA analysis was assessed by densitometry for 281 cases of colorectal adenocarcinoma. Detection of aneuploidy in a single case rose from 65% if one, to 92.5% when three or more sections, were analysed. Although aneuploid tumours had significantly larger nuclear areas than near diploid tumours (p = 0.009), densitometric measurements showed no association with clinicopathological variables. DNA content determined by densitometry was compared with that from flow cytometry on 465 tissue sections from 241 cases. Aneuploidy assessed by flow cytometry was significantly associated with that determined by densitometry (p < 0.01 for all comparisons), ploidy state being similar in 381 sections (82%, kappa = 0.63, p < 0.001), and 187 cases (77.6%, kappa = 0.57, p < 0.001). Univariate survival analysis showed that DNA densitometric variables had no significant association with survival in (a) all cases, (b) cases without lymph node metastases, or (c) cases without distant metastases. Multivariate regression analysis of densitometric and clinicopathological variables identified Dukes's stage, patient age, and tumour differentiation as the combination of variables most closely related to survival. Densitometric measurement of DNA content could not significantly improve on the prognostic model containing these three variables. It is concluded that, although the assessment of DNA content by densitometry is comparable with that of flow cytometry, conventional histological variables remain the best predictors of prognosis in colorectal cancer.

DNA mapping of colorectal neoplasms: a flow cytometric study of DNA abnormalities and proliferation

BACKGROUND

There is some evidence that neoplastic development and progression evolve through a multistep process associated with hyperproliferation and genetic alterations. Therefore, changes of proliferation and of cellular DNA content within the adenoma-carcinoma sequence were studied.

METHODS

Using a "mapping" procedure, 12 adenomas and 18 carcinomas were analyzed flow cytometrically and histologically. In addition, normal mucosa adjacent to and distant from the tumors was assessed in the same way.

RESULTS

Of 59 adenomatous fractions, 35.6% (n = 21) were aneuploid, whereas the incidence of aneuploidy was 63.5% (54/85) in the carcinomatous sites. Additional tetraploidies were identified in 5 (8.5%) and 13 (15.3%) adenomatous and carcinomatous samples, respectively. Cell proliferation, as determined by the percentage of S-phase cells, was significantly (P < 0.001) higher in the carcinomatous specimens (14.8% +/- 0.8%; mean +/- SEM) than in the adenomatous ones (8.1% +/- 0.7%). It decreased to normal mucosa adjacent to (5.1% +/- 0.5%) and distant (5.3% +/- 0.6%) from the neoplasms. DNA mapping of the tumors revealed both distinct regions and extended areas of aneuploidy and tetraploidy. There is evidence from the mapping data that aneuploid populations arise at a single focus of the adenoma and expand over large areas before a subpopulation of cells acquires the capacity of invasion.

CONCLUSIONS

These data showing consecutive DNA content abnormalities within the colorectal adenoma-carcinoma sequence provide support for genomic instability and clonal evolution as important events of tumorigenesis and progression.

Suppressive effect of doxorubicin on liver recurrence after resection of colonic VX2 cancer lesions: difference in efficacy according to the injection protocol

An animal model with liver cancer recurrence was induced by resecting colonic VX2 cancer lesions in 57 rabbits, and the effects of doxorubicin (ADR) on the recurrence were examined. Animals were divided into a control group and three chemotherapeutic groups: a portal injection group, to which ADR was injected into the portal vein after resection of the primary lesions; a peripheral injection group, to which ADR was injected into a peripheral vein after resection; and a preoperative injection group, to which an ADR dose of 0.5 mg/kg was peripherally injected 0, 1, and 2 days prior to resection followed by a portal injection of ADR 0.5 mg/kg after resection. The rate of liver recurrence was 100% in the control group, whereas it was 0% and 60% in the portal ADR 1.0 and 0.5 mg/kg injection groups, and 60% and 100% in the peripheral ADR 1.0 and 0.5 mg/kg injection groups. In the preoperative group, the rate was 0%, 100%, and 67% in the animals injected 2, 1, and 0 days prior to resection, respectively. These results suggest that portal injection or appropriate combinations of preoperative peripheral and portal injections of ADR are more effective than peripheral or portal injection alone in the suppression of liver recurrence.

Proliferative activity in gastric cancer determined with cell cycle-related monoclonal antibodies Ki-67 and p105: Analysis by flow cytometry

The proliferative activity of gastric cancer cells was determined by DNA flow cytometric (FCM) analysis and labeling rates of Ki-67 and monoclonal antibodies and proliferation-associated nuclear antigen (p105) autoantibodies in 28 patients with fresh human gastric cancer cells. By setting the cutoff line at the level as used in a negative control study without primary antibody in the same sample, the Ki-67 and p105 labeling rates were calculated by the dual fluorescence analysis. A total of 43 experiments was performed on FCM analysis for each antigen: 28 with Ki-67 and 15 with p105. The mean Ki-67 labeling rate of gastric cancer cells was 45.1% (13.9-76.3%). The Ki-67 labeling rates were significantly higher for larger size tumor, peritoneal metastasis, and advanced clinical stage. A significant correlation was found between Ki-67 labeling rate and p105 labeling rate (P < 0.05). Bivariate FCM may be an easy method for obtaining useful information of cell kinetics.

Prognostic markers of colorectal cancer: an evaluation of DNA content, epidermal growth factor receptor, and Ki-67

Between January 1989 and August 1991, 62 patients undergoing resection for colorectal adenocarcinoma were assessed in a prospective fashion on the basis of various tumor characteristics that are thought to indicate prognosis. Parameters measured included epidermal growth factor receptor (EGFr) expression, a cell membrane receptor known to be overexpressed in a variety of tumors, Ki-67, a monoclonal antibody marker of cell proliferation, as well as flow cytometry and standard histologic examination. Statistical analysis included chi square with Yates correction when appropriate, Wilcoxon W, and multivariate logistic regression. EGFr positive tumors were associated with worse Dukes' stage (27% of EGFr negative tumors were Dukes' C or D vs. 58% of EGFr positive tumors, P = 0.03), as well as more aneuploid characteristics by flow cytometry (48% EGFr negative = aneuploid vs. 82% EGFr positive = aneuploid, P = 0.01). Lymphatic invasion was more frequent in EGFr positive tumors (P = 0.03). These factors proved to be independent of each other by multivariate analysis. Ki-67 did not correlate with any of the measured parameters and was of extremely limited use in the evaluation of the study population. Multivariate analysis indicated that aneuploid tumors were associated with worse Dukes' stage than diploid tumors. Histologic parameters such as lymphatic and vascular invasion as well as histologic grade are compared to the other parameters involved with prognosis.

Surgical treatment of tumors of the distal rectum with sphincter preservation

One hundred one patients with villous adenoma or invasive carcinoma of the distal rectum treated with local excision or coloanal anastomosis were studied. Twenty-three (45%) of the 51 patients with villous adenomas had transanal excision, another 23 (45%) had a posterior proctotomy, and five (10%) had a coloanal anastomosis. Only two patients with a villous adenoma developed a recurrence requiring repeat local excision. Fifteen (30%) of the 50 patients with invasive cancer were treated by transanal excision. All had tumors confined to the submucosa or superficial muscularis. Eighteen (85%) of 21 patients having posterior proctotomy also had tumors with similar depth of invasion. Six (43%) of the 14 patients having coloanal anastomosis had Dukes' B tumors, six (43%) were Dukes' C, and another two (14%) underwent palliative resection. The overall actuarial 5-year survival was 77%. Only four patients treated by transanal excision or posterior proctotomy died of metastatic disease. In the coloanal group, two of 12 patients undergoing curative resection died of recurrent cancer, and another has a pelvic recurrence. Villous adenomas of the distal rectum and selected carcinomas may be treated with local excision and coloanal anastomosis with preservation of sphincter function with good results.

Prognostic factors in colorectal cancer

The prognostic power of the extent of tumour invasion is indisputable; Dukes' classification has repeatedly been proven to be strongly correlated with patient survival. Modifications have led only to confusion, resulting in caution being required in the classification of patients with Dukes' A tumours. In the UK, the American tumour node metastasis and Australian clinicopathological systems are frequently considered too complex for routine clinical use. Meanwhile, Jass's classification may be complicated by observer variation between pathologists, and recent evidence suggests that it offers no advantage over that of Dukes. All the conventional staging systems also fail to take the skill of the surgeon into account when determining outcome. Attempts at quantifying tumour structure have not heralded the expected major advance. For instance, the expense and uncertain prognostic value of tumour DNA content assessed by flow cytometry are likely to restrict widespread use of this technique. It may soon be possible, however, to provide optimum treatment for patients based on individual tumour doubling times. Classification using knowledge of how a small number of cells in the tumour have the ability to invade locally, enter blood vessels and metastasize would also provide important prognostic information on which treatment could be based. Until then, the ease of use and high prognostic power of Dukes' classification ensure that, after 60 years, it is still the 'gold standard' against which all other prognostic classifications in colorectal cancer should be assessed.

Colorectal carcinoma associated with ulcerative colitis: a study of prognostic indicators

Fifty-two patients with ulcerative colitis and colorectal cancer undergoing colectomy at the Mount Sinai Hospital between 1973 and 1988 were studied retrospectively to determine the correlation of age, sex, duration of colitis, tumor location, number of cancers, tumor differentiation, colloid content, presence of signet ring cells, Dukes' classification, and DNA ploidy with survival. The mean age was 45 years, with a mean duration of colitis of 21 years. Five patients (10%) had Dukes' A lesions, 17 (33%) had Dukes' B lesions, 17 (33%) had Dukes' C lesions, and 13 (25%) had distant metastases. Thirty patients (58%) had well- or moderately differentiated tumors, whereas tumors were poorly differentiated in 22 (42%). Twenty-eight patients (54%) had colloid tumors, and, in 14 (27%), signet ring cells were present. Thirty-one patients (60%) had nondiploid tumors. Actuarial analysis revealed that the 5-year survival rate was significantly worse for patients with nondiploid tumors (76% versus 32%). When stratified by stage, only patients with Dukes' C lesions showed a significant difference in survival for diploid versus nondiploid tumors. Multivariate analysis showed that the Dukes' classification was the best prognostic indicator, followed by tumor differentiation and DNA ploidy. Tumor location, colloid content, number of cancers, duration of disease, age, and sex did not correlate with the prognosis.

DNA image cytometry: a prognostic tool in rectal cancer?

In 68 patients the DNA content of tumor cells was measured by image cytometry after resection of the rectum because of cancer. In the DNA histogram a differentiation between diploid (n = 19), polyploid (n = 24), hypotriploid (n = 17), and hypertriploid (n = 8) tumors was possible. The best relapse-free survival time was found in patients with diploid tumors. The prognosis worsened from polyploid to hypotriploid and was worse in hypertriploid tumors. Testing for a prognostic advantage of diploid over aneuploid tumors without adjustment for additional factors simply by means of the log-rank statistic gave a (one-sided) P of 0.1013. In a multivariate analysis the degree of differentiation turned out most important. Again, an appropriate test for prognostic relevance of DNA content failed to be significant (P = 0.3264).

Hereditary nonpolyposis colorectal cancer (Lynch syndrome II). Diploid malignancies with prolonged survival

DNA flow cytometry was performed on 44 paraffin blocks from 16 specimens of 11 lesions in five patients from two families identified as probably having the dominant gene of the Lynch Type II syndrome. All but one specimen showed diploidy, although two such specimens were metastases and one a recurrence. The one aneuploid gastric biopsy was followed by a resection with diploidy in all 13 blocks from the malignancy and may represent a superficial change without clinical significance. The prolonged survival after discovery of malignancy in such families may be explained in part by diploidy of the lesions.

Flow cytometric analysis of DNA content in colorectal carcinoma

Over the past decade, flow cytometric DNA analysis has been employed by a number of investigators in an attempt to further define patient prognosis beyond classic pathologic staging. The results of these studies taken independently have been confusing; however, their cumulative effect suggests that flow cytometry is a useful prognostic indicator and can be used to further delineate prognosis within a specific pathologic stage. DNA nondiploid tumors are more likely to recur than diploid tumors, and patients with DNA nondiploid tumors have a poorer five-year survival than patients with DNA diploid tumors. There appears to be a weak relationship between advanced pathologic stage and DNA aneuploid tumors, although there is no clear and consistent relationship between tumor ploidy and histology. Therefore, all patients with colorectal tumors should undergo DNA ploidy analysis. Patients with DNA nondiploid tumors should be treated for biologically more aggressive disease independent of other prognostic variables. Ploidy status should be employed as a variable by which to randomize patients to both primary treatment schemes and adjuvant therapies in clinical trials.

Abnormal DNA content as a biomarker of large bowel cancer risk and prognosis

Aneuploid cell populations can be defined as those that contain an abnormal number of chromosomes or an abnormal amount of DNA. Aneuploidy can be reliably detected by flow cytometric analysis of DNA content. This technique not only identifies aneuploid cell populations but can also quantify the percent of cells in various phases of the cell cycle, thus giving an indication of the proliferative activity of a tissue. Aneuploidy occurs in approximately 60% of established colorectal cancers, and many studies have demonstrated that patients with aneuploid tumors have a poorer prognosis than patients with diploid colon cancers. Some studies have suggested that the proliferative rate of tumors, as assessed by the percent of cells in S phase, also has prognostic significance. Until recently, aneuploidy was thought to occur only in malignant tissues, but it has been clearly shown that aneuploid cell populations can be identified in benign adenomatous polyps as well as in non-neoplastic-appearing mucosa of patients with chronic ulcerative colitis and Barrett's esophagus. In chronic ulcerative colitis, aneuploidy occurs more frequently in patients with dysplasia or cancer than in those with no evidence of neoplasia. Similarly, dysplastic and malignant biopsies are more commonly aneuploid than non-neoplastic biopsies. Patients who have undergone colectomy for cancer or dysplasia in the setting of chronic ulcerative colitis frequently have multiple areas of aneuploidy throughout the remainder of their colon. Whether aneuploidy can be useful as a marker of cancer risk in patients with chronic ulcerative colitis deserves further investigation.

Metastatic mode and DNA ploidy in gastric carcinoma

We studied the amounts of nuclear DNA in gastric cancer metastases histologically and cytochemically by flow cytometry, which was performed retrospectively on paraffin-embedded specimens from 95 patients. At surgery, all cases of aneuploid cancer were positive for lymph node metastases. Liver metastases were frequently seen in aneuploid cancer (63%, P < 0.01), while lung metastases were the most common in diploid cancer (50%, P < 0.05). The incidence of peritoneal metastasis was high in undifferentiated diploid cancer (72%, P < 0.01). Local lymph node recurrence after surgery was more common in aneuploid than in diploid cancer (P < 0.01). The incidence of bone and distant lymph node metastasis was found to be strongly dependent on tissue differentiation. The DNA ploidy pattern is thus considered to be closely linked to lymph node, liver, and lung metastases in gastric cancer.

DNA ploidy of colorectal cancer and synchronous polyps in polyposis coli

Sixteen patients with polyposis coli and cancer were studied retrospectively to determine the incidence of DNA ploidy abnormalities in the tumors and synchronous polyps. Six patients (37 percent) had nondiploid tumors. Nondiploid tumors were more likely to be advanced and had a significantly worse prognosis (17 percent vs. 76 percent 5-year survival; P less than 0.01). Only 4 of 20 polyps studied were nondiploid. There was no association between tumor and polyp ploidy. All nondiploid polyps were found in patients with synchronous diploid cancers. Patients with nondiploid polyps were more likely to be older and have more advanced tumors than those with diploid polyps. DNA ploidy abnormalities seem to occur with the same frequency in polyposis coli as in the nonpolyposis population, and tumor ploidy correlates with prognosis.

Flow cytometric quantitation of the proliferation-associated nuclear antigen p105 and DNA content in advanced gastric cancers

Flow cytometric quantitation of the proliferation-associated nuclear antigen p105 was done on cancer cell suspensions from 114 advanced gastric cancers and correlated with clinical behavior. DNA diploidy was observed in 45 (39.5%) and aneuploidy in 69 (60.5%) cases. By setting the cutoff line at the level used in a negative control study without primary antibody in the same sample, the p105-labeling rate was calculated by the p105-DNA dual fluorescence analysis. The mean p105-labeling rate was 37.7% (range, 9.3% to 79.0%). The p105-labeling rates were significantly higher (P less than 0.05) for aneuploid DNA, liver metastasis, vascular invasion, and histologically well-differentiated tumors. The 5-year survival rate of patients with high p105-labeling tumors (p105-labeling rate, greater than 30%) was significantly poorer (P less than 0.01) than that of patients with low-labeling tumors. When the p105-labeling rate and the clinicopathologic parameters were entered simultaneously into the Cox regression model, the stage of disease, DNA ploidy, p105-labeling rate, and vascular invasion emerged as independent prognostic parameters. These findings indicate that the measurement of p105 may provide useful information for predicting prognosis in advanced gastric cancers.

Turcot's syndrome. Flow cytometric analysis

Turcot's syndrome is a rare, genetically transmittable disease in which patients with colonic polyposis (possibly complicated by the progression to adenocarcinoma) have malignant central nervous system neoplasms. Dominant, recessive, and sporadic cases have been described. A 26-year-old man is reported with no relevant family history who had intermittent abdominal discomfort in 1986. Sigmoidoscopy revealed numerous polyps, several of which showed carcinomatous change. Dukes' Stage C colorectal carcinoma was diagnosed. Treatment consisted of total colectomy with construction of a Koch's pouch. He remained well for 3 years until onset of headache, nausea, and vomiting. Computed tomographic scan disclosed a large, circumscribed, enhancing, right frontoparietal mass. After craniotomy and partial resection, histologic review disclosed anaplastic astrocytoma. He received cranial radiation therapy, 6000 cGy, by parallel opposed ports to the tumor bed, and carmustine 200 mg/m2 intravenously every 8 weeks. Flow cytometric DNA analysis was done on the paraffin-embedded archival material from the patient's normal colon, colonic adenocarcinoma, and anaplastic astrocytoma. DNA histograms revealed diploid distributions in all three samples. The G2/M fraction of the astrocytoma was elevated at 16%, and the S-phase fraction of the colonic adenocarcinoma was 19.4%.

DNA analysis of oral leukoplakia by flow cytometry

DNA ploidy of 19 oral leukoplakias with and without epithelial dysplasia was investigated and the results were compared with 11 normal gingival biopsies, 14 oral benign tumours and 50 oral squamous cell carcinomas. The results suggest a possible relationship between DNA aneuploidy and oral leukoplakias or squamous cell carcinomas, as 32% of the oral leukoplakias and 48% of the oral squamous cell carcinomas were aneuploid although all the normal gingival biopsies and the benign oral tumours examined were diploid. No significant relationship was observed, however, between DNA ploidy and epithelial dysplasia in the leukoplakias.

Near diploid large bowel carcinomas have better five-year survival than aneuploid ones

One hundred patients who underwent surgery for large bowel carcinoma between 1978 and 1982 were examined by flow cytometric DNA quantitation of fresh tumor specimens and divided into an aneuploid (AN) group of 63 and a near diploid (ND) one of 37. All patients were followed until death (n = 63) or until December 31, 1988. Forty-one patients (65%) with AN tumors died of cancer, as did 12 patients (32%) with ND carcinomas. Thus patients with ND tumors had a better survival rate (P = 0.04) than did those with AN ones. The difference was apparent in Dukes' Stages A, B, and C, but not in Stage D. All patients with tumors in this stage died from their carcinomas irrespective of ploidy group. Multiple regression analyses (Cox) of prognostic factors revealed that the most important prognostic variables were (in descending order) Dukes' Stage D, Dukes' Stage C, and DNA ploidy pattern. Histologic grade was not significant as an independent prognostic variable. These results indicate that the presence of a distinctly aneuploid DNA ploidy pattern in large bowel carcinoma is an important prognostic variable that worsens survival rates significantly.