Diagnostic radiography and adult acute myeloid leukaemia: an interview and medical chart review study.

BACKGROUND: Aetiology of acute myeloid leukaemia (AML) is not well understood, perhaps because of its distinct subtypes. High-dose ionising radiation is a known risk factor, but less is known about risk from low-dose exposure such as from diagnostic radiography. METHODS: Subjects were 412 matched case-control pairs. Ten-year subject histories of diagnostic radiography were based on interview and medical records. RESULTS: There was no convincing association between AML risk and ionising radiation exposure from diagnostic imaging procedures, either for AML overall or for any AML subtype. CONCLUSION: The association between diagnostic radiography and AML risk remains uncertain.

Angiogenesis in bladder cancer: relationship between microvessel density and tumor prognosis.

BACKGROUND: Tumor stage, histologic grade, and regional lymph node status are currently used to obtain prognostic information about bladder cancers. However, additional prognostic indicators are needed to aid clinicians in selecting patients who would benefit most from specific therapies. A majority of studies assessing the prognostic value of measuring tumor angiogenesis (i.e., measurement of tumor microvessel densities) have found a positive association between increasing microvessel densities and worsening prognosis. PURPOSE: We explored the relationship between established prognostic indicators and the extent of tumor-associated angiogenesis in patients with invasive transitional cell carcinoma (TCC) of the bladder, and we determined whether tumor microvessel density measurement could be used independently to predict bladder tumor behavior. METHODS: Tumor tissue was obtained from 164 patients with invasive primary TCC of the bladder. The extent of tumor-associated angiogenesis in this tissue was evaluated by immunohistochemical methods using HPCA-1, a mouse monoclonal antibody directed against the endothelial cell antigen, CD34. The number of microvessels in a 200x microscopic high-power field (hpf) containing the area of greatest neovascularization within or immediately adjacent to each tumor was determined. The patient population was then divided into three equivalently sized groups, with tumors containing low (< or = 64), intermediate (65-99), or high (> or = 100) numbers of microvessels per hpf. Kaplan-Meier product limit estimates of overall survival and the complement of cumulative incidence curves for recurrence-free survival were plotted. When analyzing survival or recurrence, the logrank test was used to compare groups of patients with and without stratification according to tumor stage. Analysis of variance was used to test for an association between microvessel density and established prognostic variables. Reported P values are from two-sided tests. RESULTS: Microvessel density was significantly associated with disease-free (P < .0001) and overall (P = .0007) survival. The estimated probabilities of recurrence at 5 years were 19% (95% confidence interval [CI] = 8-29), 56% (95% CI = 43-69), and 68% (95% CI = 55-81) for patients with lowest, intermediate, and highest microvessel counts, respectively. Overall survival at 5 years was estimated to be 68% (95% CI = 56-81), 44% (95% CI = 30-57), and 34% (95% CI = 21-47) for the same three patient groups. Microvessel density was associated with disease progression in patients with organ-confined tumors, tumors extending through the bladder wall, and tumors that had spread to regional lymph nodes. Tumor angiogenesis was found to be an independent prognostic indicator when evaluated in the presence of histologic grade, pathologic stage, and regional lymph node status. CONCLUSION: Tumor angiogenesis, as determined by microvessel density measurement, is an independent prognostic indicator for patients with invasive TCC of the bladder.

High frequency of chromosome 9p allelic loss and CDKN2 tumor suppressor gene alterations in squamous cell carcinoma of the bladder.

BACKGROUND: In the Western Hemisphere, 90% of bladder cancers are transitional cell carcinomas, while only 7% are classified as squamous cell carcinomas. In contrast, in Egypt and regions of the Middle East and Africa, where infection by the trematode Schistosoma haematobium is endemic, squamous cell carcinoma is the most common bladder cancer as well as the most common cancer in men. PURPOSE: We planned experiments to understand the genetic defects underlying the development of squamous cell carcinoma and to determine if the morphologically and clinically distinct squamous cell carcinoma and transitional cell carcinoma of the bladder evolve following different genetic alterations. METHODS: Squamous cell carcinoma specimens from high-risk (Egypt, n = 19) and low-risk (Sweden, n = 12) populations were examined for genetic defects known to be involved in transitional cell carcinoma tumorigenesis. Homozygous deletions of the CDKN2 tumor suppressor gene were detected by comparative multiplex polymerase chain reaction. Mutations in the CDKN2 and p53 (also known as TP53) genes were analyzed by single-strand conformation polymorphism and DNA sequencing. Immunohistochemical staining of p53 protein was also performed. Allelic losses in chromosome arms 9p, 9q, and 17p were determined by microsatellite analysis. RESULTS: Homozygous deletions and sequence mutations in the CDKN2 gene were found in 67% (eight of 12) of squamous cell carcinoma specimens, a frequency three times higher than that reported for uncultured transitional cell carcinomas (P = .009). Hemizygous and homozygous deletions in 9p, where CDKN2 resides, were found in 92% (11 of 12) of uncultured squamous cell carcinomas, while only about 39% (35 of 90) of transitional cell carcinomas showed these losses (P = .001). Deletions in 9p with no change in 9q were found in 92% (10 of 11) of squamous cell carcinomas compared with only 10% (11 of 110) of transitional cell carcinomas (P < .001) reported in the literature. The frequency of p53 mutations in squamous cell carcinomas was similar to that reported for invasive transitional cell carcinomas (60%), but the type and position of mutations differed between the two tumor types. Allelic losses in chromosome arm 17p, where the p53 gene resides, were found to be less frequent in squamous cell carcinomas (38%) than in invasive transitional cell carcinomas (60%). CONCLUSIONS: Our results suggest that a putative tumor suppressor gene on 9p, possibly CDKN2, may contribute to squamous cell carcinoma tumorigenesis. Our data on squamous cell carcinoma and previously reported data on transitional cell carcinoma indicate that these two bladder carcinomas differ in their genetic alterations, suggesting that distinct underlying genetic defects may explain, at least in part, the pathological differences between the two tumors of the bladder epithelium. IMPLICATIONS: Development of diagnostic and therapeutic strategies for squamous cell carcinoma of the bladder based on its distinct genetic alterations is warranted.

Thrombospondin-1 expression in bladder cancer: association with p53 alterations, tumor angiogenesis, and tumor progression.

BACKGROUND: Thrombospondin-1 (TSP) is a 430-kd glycoprotein that is an important component of the extracellular matrix and is known to be a potent inhibitor of angiogenesis (i.e., formation of new blood vessels) both in vitro and in vivo. Several reports suggest that TSP possesses tumor suppressor function, possibly through its ability to inhibit tumor neovascularization. It has recently been shown that TSP expression is enhanced by the product of the p53 gene (also known as TP53). PURPOSE: We examined the role of TSP expression in tumor recurrence and overall survival in patients with invasive bladder cancer. We also examined the relationship between alterations in p53 protein expression, TSP expression, and tumor angiogenesis. METHODS: Tumors from 163 patients (with a median follow-up of 7.7 years) who underwent radical cystectomy for invasive transitional cell carcinoma of the bladder (63 patients with organ-confined disease and no lymph node involvement, 48 patients with extravesical extension of the disease and no lymph node involvement, and 52 patients with metastasis to regional lymph nodes) were examined for TSP expression by immunohistochemistry, utilizing monoclonal antibody MA-II, which recognizes an epitope in the amino-terminal region of TSP. For each tumor, microvessel density counts and p53 protein expression status (via immunohistochemistry) were also determined. TSP expression was graded as low, moderate, or high without knowledge of clinical outcome, p53 status, and microvessel density count; tumors with moderate and high TSP levels were considered as one group. Groups of patients were compared by Kaplan-Meier product limit estimates of overall survival, the complement of cumulative incidence curves for recurrence-free survival, and the stratified logrank test. Reported P values are two-sided. RESULTS: TSP expression was significantly associated with disease recurrence (P = .009) and overall survival (P = .023). Patients with low TSP expression exhibited increased recurrence rates and decreased overall survival. TSP expression was an independent predictor of disease recurrence (P = .002) and overall survival (P = .01) after stratifying for tumor stage, lymph node status, and histologic grade, but it was not independent of p53 status. TSP expression was significantly associated with p53 expression status (P = .001) and microvessel density counts (P = .001). Tumors with p53 alterations were significantly more likely to demonstrate low TSP expression, and tumors with low TSP expression were significantly more likely to demonstrate high microvessel density counts. Results of an analysis of variance were compatible with the hypothesis that p53 affects tumor angiogenesis by regulating the level of TSP expression. CONCLUSIONS AND IMPLICATIONS: These data support the concept that TSP may possess a tumor-inhibitory function. TSP may act, in part, through the regulation of tumor neovascularity. These results may also provide insight into one mechanism by which p53 exerts its tumor suppressor effects, i.e., through the control of tumor angiogenesis.

Contiguous patches of normal human mammary epithelium derived from a single stem cell: implications for breast carcinogenesis.

Tissue clonality can be assessed in females by analyzing the methylation status of polymorphic DNA markers on X-linked genes because extensive de novo methylation of one allele at the preimplantation stage is associated with its permanent inactivation. We applied X chromosome inactivation toward understanding human breast morphogenesis by examining the nonmalignant breast epithelium from two reduction mammaplasties and a mastectomy. We found that entire lobules and large ducts of normal breast tissue have the same X chromosome inactivated, suggesting that they are derived from the same stem cell. The regions of inactivation of a particular X chromosome do not extend over an entire breast, so that ducts and lobules with opposite chromosomes inactivated are present within a single breast. Potential relevance of these observations for malignant transformation is discussed.

Southern blot analysis of DNA extracted from formalin-fixed pathology specimens.

We have developed a method for the extraction of DNA from formalin-fixed, paraffin-embedded pathology specimens. High-molecular-weight DNA was recovered from well-fixed nonautolyzed samples of viable tissue. DNA recovered from samples exposed to picric acid or mercuric chloride containing fixatives was not intact. Increasing the formalin fixation time decreased the amount of intact DNA available. When these limitations were taken into consideration, the procedure allowed for the removal of degraded and chemically modified DNA from the preparation, and the final product was suitable for quantitative and qualitative analysis by Southern or dot blotting techniques. Digestion with methylation-sensitive restriction endonucleases showed that DNA methylation patterns were not altered after formalin fixation.

Allelic losses of chromosomes 9, 11, and 17 in human bladder cancer.

Twenty-five human bladder tumors were examined for loss of heterozygosity of markers on chromosomes 6p, 9q, 11p, 14q, and 17p. These studies show that all of the markers were reduced to homozygosity in at least some of the tumors. They also confirmed earlier studies by Fearon et al. [Nature (Lond.), 318: 377-380, 1985] that approximately 40% of bladder tumors were reduced to homozygosity for markers on chromosome 11p. However, the greatest frequency of allelic loss was seen for chromosomes 9q (67% of informative cases) and 17p (63% of informative cases) with both chromosomes being lost concordantly in 10 out of 20 informative tumors. Allelic loss of chromosome 9q has not been previously observed with other human cancers; however, deletions of 17p have been reported in breast, lung, and colorectal carcinomas. The data raise the interesting possibility that allelic losses of specific chromosomes might be a feature of cancer in a particular differentiated cell type whereas loss of other chromosomes harboring more generally acting tumor suppressor genes might be a common feature of human cancers.

Microsatellite instability in bladder cancer.

Somatic instability at microsatellite repeats was detected in 6 of 200 transitional cell carcinomas of the bladder. Instabilities were apparent as changes in (GT)n repeat lengths on human chromosome 9 for four tumors and as alterations in a (CAG)n repeat in the androgen receptor gene on the X chromosome for three tumors. Single locus alterations were detected in three tumors, while three other tumors revealed changes in two or more loci. In one tumor we found microsatellite instability in all five loci analyzed on chromosome 9. The alterations detected were either minor 2-base pair changes or larger (> 2 base pairs) alterations in repeat length. All six tumors were low stage (Ta-T1), suggesting that these alterations can occur early in bladder tumorigenesis.

Role of chromosome 9 in human bladder cancer.

The tumors of 20 patients with multifocal primary transitional cell carcinoma of the bladder or lymph node metastases were examined for molecular genetic defects which we have previously found to be present in > 50% of invasive tumors. These included loss of heterozygosity (LOH) of chromosome 9, which occurs in superficial as well as invasive bladder tumors, and LOH of chromosome 17p and p53 mutations, which are commonly found only in invasive tumors. Analysis of multiple or recurrent primary tumors in 7 patients for these markers was generally consistent with recently published data that the tumors are monoclonal in origin and that p53 mutations occur as a late event in the generation of invasive bladder cancers. Comparison of the primary tumors and metastases to regional lymph nodes in 14 patients demonstrated a complete concordance between the molecular genetic defects present, showing that LOH of chromosomes 9 and 17p and p53 mutations occurred in the primary tumors before metastasis. Because of the importance of chromosome 9 in bladder cancer, we mapped the location of a putative tumor suppressor gene by restriction fragment length polymorphism analysis of 123 cases obtained in this and earlier studies. Most of the tumors showed LOH for more than one marker on chromosome 9. Results of mapping of 4 tumors with partial deletion of chromosome 9 suggests that the tumor suppressor gene is located between 9p12 and 9q34.1.

Progressive increases in de novo methylation of CpG islands in bladder cancer.

We conducted a quantitative analysis of the extent of de novo methylation of four CpG islands in human urinary transitional cell carcinomas of different stages and grades to determine how frequently these CpG islands became methylated in transition cell carcinomas during progression. The CpG islands included exon 5 of PAX6, exon 2 of p16, the 5' end of the deleted in bladder cancer gene, and the 5' end of transmembrane protein containing epidermal growth factor and follistatin domains. These sequences were not methylated in normal urothelial tissues; however, 48 of the 54 tumors examined (89%) showed methylation levels in excess of 20% for at least one of the markers. The number of markers concurrently methylated in individual tumors increased with the stage of the tumor, with several of the more aggressive invasive cancers showing hypermethylation of all four markers compared with the less aggressive invasive cancers. However, considerable methylation defects were present in superficial, preinvasive, papillary tumors. These data demonstrate that 89% of bladder cancers have increased methylation of CpG islands relative to their normal counterparts and suggest the occurrence of a hypermethylator phenotype in which multiple independent CpG islands become concurrently methylated in individual tumors in a process associated with tumor progression.

Allelic loss of chromosome 17p distinguishes high grade from low grade transitional cell carcinomas of the bladder.

Forty-three transitional cell carcinomas of the bladder of differing grades and stages were examined for reduction to homozygosity for chromosomes 9q, 11p, and 17p. Allelic loss of chromosome 9q was seen in 24 of 38 informative grades II, III, and IV tumors providing further evidence for a bladder tumor suppressor gene on this chromosome. In contrast to the grade-independent involvement of chromosome 9q, allelic losses of chromosomes 11p and 17p were seen only in grade III and IV tumors. The results with chromosome 17p were particularly striking and showed that 0 of 10 grade II versus 20 of 31 grade III and IV tumors had allelic losses for this chromosome harboring the p53 tumor suppressor gene often mutated in other human cancers. The data suggest that cumulative genetic damage is sustained in transitional cell carcinomas and that one of the underlying molecular mechanisms distinguishing low grade from high grade tumors involves chromosome 17p.

Distinct pattern of p53 mutations in bladder cancer: relationship to tobacco usage.

A distinct mutational spectrum for the p53 tumor suppressor gene in bladder carcinomas was established in patients with known exposures to cigarette smoke. Single-strand conformational polymorphism analysis of exons 5 through 8 of the p53 gene showed inactivating mutations in 16 of 40 (40%) bladder tumors from smokers and 13 of 40 (33%) tumors from lifetime nonsmokers. Overall, 13 of the 50 (26%) total point mutations discovered in this and previous work were G:C-->C:G transversions, a relatively rare mutational type in human tumors. In six tumors, identical AGA (Arg)-->ACA (Thr) point mutations at codon 280 were observed, suggesting a mutational hotspot in these tumors. Comparison of the mutational spectra from smokers and nonsmokers revealed no obvious differences in the types or positions of inactivating mutations; however, 5 of 15 tumors containing point mutations from cigarette smokers had double mutations, four of which were tandem mutations on the same allele. No double mutations were found in tumors from nonsmoking patients. None of the mutations in smokers were G:C-->T:A transversions, which would be anticipated for exposure to the suspected cigarette smoke carcinogen 4-aminobiphenyl. The results suggest that, although cigarette smoke exposure may not significantly alter the kinds of mutations sustained in the p53 gene, it may act to increase the extent of DNA damage per mutagenic event.

Early acquisition of homozygous deletions of p16/p19 during squamous cell carcinogenesis and genetic mosaicism in bladder cancer.

We looked for p16/p19 deletion and p16 promoter methylation, as well as loss of 9p21 heterozygosity in pure squamous cell carcinomas (SCC), and in transitional cell carcinomas (TCC) of the bladder with SCC components. Homozygous deletion of p16/p19 was detected in 11 of 21 (52%) cases of pure SCCs and in three of ten (30%) cases of TCC with SCC. Three cases of TCC with SCC had p16/p19 deletion, hypermethylation of the p16 promoter, or LOH on 9p21 only in the SCC components, suggesting that these molecular alterations occurred preferentially in SCC. Interestingly, homozygous deletion of p16/p19 was observed in squamous metaplasia from bladder cancer patients (five of 11, 45%), showing that this change occurred in preneoplastic cells. On the other hand, p16/p19 deletions were not found in squamous metaplasias from non cancerous patients. Hypermethylation of the p16 promoter was observed in two of 14 tumors (14%) and none of seven metaplasias examined. These data suggest that: (a) p16/p19 deletion is associated with early carcinogenesis of SCC of the bladder, and squamous metaplasia of the bladder cancer patient has already sustained genetic changes found in cancer, and (b) genetic mosaicism occurs in cases of TCC with SCC, with the SCC component showing more frequent 9p21 alterations than the TCC component.

Relationship of tumor angiogenesis and nuclear p53 accumulation in invasive bladder cancer.

The purpose of this investigation was to evaluate the relationship between tumor angiogenesis and nuclear p53 accumulation in invasive bladder cancer. We studied 161 patients with invasive transitional cell carcinoma of the bladder who had previously undergone radical cystectomy. Analysis was performed to determine the presence of p53 nuclear accumulation and extent of tumor-associated angiogenesis. p53 status identified a group of patients at high risk for tumor progression (p53-altered tumors), and microvessel density determinations added additional prognostic information by identifying a subset of aggressive tumors within the wild-type p53 subgroup. At 5 years, patients with tumors exhibiting no evidence of p53 alterations and low microvessel counts demonstrated 3% recurrence and 88% survival, compared to 43% recurrence and 59% overall survival for patients with intermediate vessel counts and 61% recurrence and 43% overall survival for patients with the highest vessel counts (P < 0.001 and P = 0.003, respectively). Angiogenesis also provides additional prognostic information to patients with tumors that demonstrate p53 alterations. An association between angiogenesis and p53 status did exist (P = 0. 05); however, 27% of the tumors that showed no evidence of p53 alterations exhibited high microvessel counts, and 26% of tumors with evidence of p53 alterations had low microvessel counts. Tumor-associated angiogenesis adds additional useful prognostic information to that which is obtained from p53 status in patients with invasive transitional cell carcinoma of the bladder. Although an association between p53 status and the degree of angiogenesis was identified, other factors appear to play a role in the regulation of tumor-induced neovasularization.

B-cell lymphoma in two monogamous homosexual men.

Opportunistic infections and malignant neoplasms have been described in homosexual men in association with immunologic abnormalities. We observed the development of malignant B-cell lymphomas in two homosexual men who had had a monogamous relationship for two years. Patient 1 had an aggressive, monoclonal, small, noncleaved, non-Burkitt's lymphoma ("undifferentiated lymphoma"), associated with severe immunocompromise. Patient 2 manifested a monoclonal, small, cleaved, follicular center cell lymphoma, with a follicular pattern, two months later. No common acute infection was detected. Staining for Epstein-Barr nuclear antigen in malignant tissue was negative in the second patient. However, the possibility of a transmissible agent as a causative factor cannot be excluded, and further study of similar patients is warranted.

Presence of p53 mutations in primary nasopharyngeal carcinoma (NPC) in non-Asians of Los Angeles, California, a low-risk population for NPC.

Mutatins of the p53 tumor suppressor gene are rare in nasopharyngeal carcinoma (NPC) patients who reside in high-risk areas, such as Southeastern China. Among this high-risk group, a pre-existing infection with the EBV and consumption of Cantonese salted fish are closely associated with NPC. We investigated the prevalence of p53 mutations in 28 primary NPC specimens from white (including Hispanic) and African-American patients in Los Angeles, who are at low risk for NPC. Using PCR-based single-strand conformational polymorphism and direct sequencing, we found four mutations (14%) in exons 5-8 of the p53 gene in four patients. All were C-to-T transition mutations: two were present in exon 5-one at codon 142 [CCT (Pro)-->CTT (Leu)] and another at codon 144 [CAG (Gln)-->TAG (stop codon)]. The other two mutations were identified in exon 8: one at codon 273 [CGT (Arg)-->CAT (His)], a CpG site, and one at codon 271, a silent mutation [GAG (Glu)-->GAA (Glu)]. This is the first report investigating the presence of p53 missense mutations in NPC among a low-risk population. Our data indicate that p53 is also an infrequent event among NPC patients at low risk for the disease.

Primary non-Hodgkin's lymphoma and pseudolymphoma of lung: a study of 161 patients.

The authors studied 161 cases of primary non-Hodgkin's lymphomas and pseudolymphomas of lung. Small lymphocytic proliferations, which they believe to be lymphomas, constituted 31.6 per cent of cases; plasmacytoid lymphocytic and small cleaved follicular center cell lymphomas (Lukes-Collins system), 22.4 and 11.8 per cent of cases, respectively; and the remaining follicular center cell lymphomas and B-immunoblastic sarcomas, 5.6 per cent of cases. Pseudolymphomas constituted 14 per cent of cases. Most patients were elderly and asymptomatic; in most cases a solitary nodule or infiltrate was observed on a chest radiograph. Radiographic evidence of effusion was found in both lymphomas and pseudolymphomas, but hilar adenopathy was restricted to lymphomas. A few peribronchial reactive germinal centers and intralesional giant cells/granulomas were seen frequently in unequivocal lymphomas, so their presence cannot be used to exclude neoplasia. A generally monomorphic cell population and invasion of bronchial cartilage or visceral pleura are suggestive of malignancy, whereas primitive cytologic appearance and invasion of lymph nodes or parietal pleura are pathognomonic of malignancy. Diffusely admixed mature lymphocytes and plasma cells with numerous reactive follicles suggest pseudolymphomas. Immunologic determination of clonality may be diagnostically definitive. Most localized lesions in lung were treated by surgical resection, whereas in cases of extensive pulmonary disease, biopsies were performed and patients were treated by chemotherapy or irradiation. Both lymphomas and pseudolymphomas recurred, most often within three years. Pseudolymphoma recurred only in lung. When distant spread of lymphoma occurred, it commonly involved extranodal sites. Only 18 of 101 patients with lymphoma died with or of tumor, and no patient with pseudolymphoma died of disease. Neither histologic subtype among the "small cell" lymphoid lymphomas nor the presence of regional node involvement was prognostically significant, but pleural effusion on the initial chest radiograph was a significant predictor of both recurrence and mortality.

Primary mucosal malignant melanoma: an immunohistochemical study of 12 cases with comparison to cutaneous and metastatic melanomas.

Immunohistochemical analysis of 40 formalin-fixed, paraffin-embedded malignant melanomas (12 primary mucosal, 16 primary cutaneous, and 12 metastatic cutaneous) was performed to study the possible differences in immunostaining profiles according to location. The majority of melanomas were reactive with a polyclonal antibody to S100 protein (P-S100; 85%), a monoclonal melanoma-specific antibody (HMB-45; 88%), and a monoclonal antibody to vimentin (90%), and there were no differences in staining profiles for these antibodies by anatomic location. In contrast, while 13 of 16 cutaneous melanomas (81%) and ten of 12 metastatic melanomas (83%) were reactive with a monoclonal antibody to S100 protein (MoAb-079), only five of 12 mucosal tumors (42%) showed positive staining for MoAb-079. Similarly, 14 cutaneous melanomas (88%) and 11 metastatic melanomas (92%) showed positive staining for neuron specific enolase (NSE), while only four mucosal melanomas (33%) were NSE-positive. Of the 40 melanomas, all but two were reactive with either P-S100, MoAb-079, or HMB-45. These findings suggest that MoAb-079 and NSE may be less sensitive markers than P-S100 and HMB-45 for routinely processed mucosal melanomas as compared with cutaneous and metastatic tumors.

Flow cytometric DNA and nuclear antigen content in astrocytic neoplasms.

Simultaneous flow cytometric DNA content and proliferation-associated nuclear antigen (p105) quantitation was performed on 23 astrocytic tumors and the results correlated with histologic subtype. Three of nine anaplastic astrocytomas and one of ten glioblastomas had an identifiable aneuploid peak, while all four well differentiated astrocytomas were diploid. Cell cycle analysis of malignant gliomas revealed a higher mean percentage of S and G2M cells compared to well differentiated astrocytomas but there was considerable overlap between histologic subtypes. Nuclear antigen analysis of diploid tumors showed a higher mean p105 fluorescence of S + G2M cells than G0G1 cells from the same case but there were no apparent differences in p105 expression by histologic subtype. Aneuploid tumors showed enhanced expression of p105 relative to diploid cells. The findings suggest that the aggressive course of high grade glial tumors may be related to an abnormal DNA stemline or an increase in proliferative activity.

A simple and practical technic for detecting cancer cells in urine and urinary bladder washings by flow cytometry.

DNA measurement by flow cytometry has been demonstrated to be a potentially useful technic in the diagnosis of bladder cancer by detecting neoplastic cells in bladder washings and urine specimens. The authors' goal was to develop a simple and practical method utilizing the new generation of cytofluorographs designed for use in the clinical laboratory. This method combined direct fixation with cell lysis yielding fixed intact nuclei. Following RNase and pepsin digestion, the nuclei were separated from debris and aggregates on a sucrose barrier, stained with ethidium bromide, and analyzed with an argon laser analytic cytofluorograph. Urines and bladder washings from 14 patients with positive urinary cytology and histologically diagnosed bladder cancers were compared with specimens from patients without urothelial malignancies. DNA histograms clearly delineated aneuploid from diploid populations and often identified S, G2M, and G1 phase nuclei. Aneuploid populations have been detected in all tumor specimens with positive cytologies studied to date.