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M Banerjee

Publications and source records attributed to M Banerjee.

At least 37 records · Page 2Linked to original sources
PubMed2000

Phosphatase Activities of Endolithic Communities in Rocks of the Antarctic Dry Valleys.

Phosphorus is scarce in Beacon Sandstone of the McMurdo Dry Valleys, Antarctica, and any input from precipitation is minimal. In endolithic microbial communities recycling of P by the action of phosphatases may therefore be important. The phosphatase activities of three different types of endolithic communities in the McMurdo Dry Valley, Antarctica, were studied in the laboratory. The dominant phototrophs were Chroococcidiopsis, mixed Gloeocapsa and Trebouxia, and Trebouxia. Bacteria were also visually conspicuous in the latter two communities, and the Trebouxia in both cases formed a lichenized association with fungal hyphae. In each case marked phosphomonoesterase (PMEase) activity was found in assays with 4-methylumbelliferyl phosphate (MUP) or p-nitrophenyl phosphate as substrate, and phosphodiesterase activity with bis-p-nitrophenyl phosphate as substrate. The pH optimum of PMEase (assayed at 0.5 pH intervals) of the Chroococcidiopsis, Gloeocapsa-Trebouxia, and Trebouxia communities was 9.5, 5.5, and 8.0, respectively. These values are similar for aqueous extracts of the respective rocks (pH 9.2, 6.2, 7.5). All three communities showed significantly higher PMEase activity at 5 degrees than 1 degrees C, and the first two also showed much higher activity at 5 degrees than 10 degrees C. All three communities also showed slightly lower activity in the light (7 µmol photon m(-2) s(-1)) than the dark; this was found with all substrates and substrate concentrations. Prior exposure of a moistened sample to light for 2 h led to a reduction in activity even when the subsequent assay was done in the dark. The rate of PMEase activity (using 100 µM MUP) in the Gloeocapsa-Trebouxia and Trebouxia communities was approximately linear with time up to 24 h, whereas the Chroococcidiopsis community showed a marked decrease after 6 h. At least part of this was due to retention of the 4-methylumbelliferone (MU) hydrolysis product. In spite of the assays being conducted on a whole community, the activity-substrate relationship in each case quite closely resembled a typical Michaelis-Menten relationship. Estimates were made of the apparent half-saturation value and the concentration of MUP required to support half-maximal rates. The apparent K (m) values were: Chroococcidiopis, 230 µM; Gloeocapsa-Trebouxia 169 µM; Trebouxia, 135 µM. The respective values for apparent V (max) were 0.053, 0.55, and 0.35 µmol MU g(-1) h(-1). In view of the greater dependence of these communities on the rock for their sole supply of P than for C and probably N, it is suggested that the cycling of P within the communities is a key factor influencing their overall metabolic activity when moisture permits their activation. </hea

Journal Article↗
PubMed2000

Prostate cancer biochemical recurrence stage for stage is more frequent among African-American than white men with locally advanced but not organ-confined disease.

OBJECTIVES: To determine whether outcome differences between African-American men (AAM) and white men with prostate cancer (PCa) will still be present if we control for stage in a large cohort of men. It is well established that AAM have a worse outcome from PCa than white men. METHODS: We examined 848 consecutive patients who underwent radical prostatectomy at Wayne State University, Karmanos Cancer Institute, between 1991 and 1995. The mean follow-up was 34 months (range 1.5 to 75). We included men with Gleason score 7 (4 + 3) with those men with Gleason score 8 to 10 for racial/ethnic comparisons. RESULTS: AAM and white men diagnosed with organ-confined PCa demonstrated similar prostate-specific antigen (PSA) levels, Gleason grade, and biochemical recurrence. However, AAM diagnosed with non-organ-confined disease demonstrated higher PSA levels and a higher incidence of recurrence than did white men with non-organ-confined disease. There was a trend toward AAM having a greater proportion of high-grade lesions than white men when PCa was not organ confined. The evidence suggests that the difference in recurrence among AAM versus white men is based on pretreatment PSA, grade, extracapsular extension, and positive surgical margins. Seminal vesicle invasion predicted a worse prognosis equally for both AAM and white men. CONCLUSIONS: A difference in biochemical recurrence was not detected between AAM and white men with organ-confined PCa after radical prostatectomy. PSA was higher in AAM than in white men with pathologically locally advanced PCa, and the biochemical recurrence was greater. AAM had a greater percentage of high Gleason grade lesions compared with white men, and this difference approached statistical significance. We hypothesize that AAM have a more rapid growth rate of PCa, which may be responsible for these clinical findings. Further investigations of the biology of PCa are needed to understand these findings.

Black or African American↗
PubMed2000

Genetic analysis of the strong gyrase site (SGS) of bacteriophage Mu: localization of determinants required for promoting Mu replication.

The Mu strong gyrase site (SGS), located in the centre of the Mu genome, is required for efficient Mu replication, as it promotes synapsis of the prophage termini. Other gyrase sites tested, even very strong ones, were unable to substitute for the SGS in Mu replication. To determine the features required for its unique properties, a deletion analysis was performed on the SGS. For this analysis, we defined the 20 bp centred on the midpoint of the 4 bp staggered cleavage made by gyrase to be the 'core' and the flanking sequences to be the 'arms'. The deletion analysis showed that (i) approximately 40 bp of the right arm is required, in addition to core sequences, for both efficient Mu replication and gyrase cleavage; and (ii) the left arm was not required for efficient Mu replication, although it was required for efficient gyrase cleavage. These observations implicated the right arm as the unique feature of the SGS. The second observation showed that strong gyrase cleavage and Mu replication could be dissociated and suggested that even weak gyrase sites, if supplied with the right arm of the SGS, could promote Mu replication. Hybrid sites were constructed with gyrase sites that could not support efficient Mu replication. The SGS right arm was used to replace one arm of the strong pSC101 gyrase site or the weaker pBR322 site. The pSC101 hybrid site allowed efficient Mu replication, whereas the pBR322 hybrid site allowed substantial, but reduced, replication. Hence, it appears that optimal Mu replication requires a central strong gyrase site with the properties imparted by the right arm sequences. Possible roles for the SGS right arm in Mu replication are addressed.

Bacteriophage mu↗
PubMed2000

Immunohistochemical expression of bcl-2 and p53 oncoproteins: correlation with Ki67 proliferation index and prognostic histopathologic parameters in colorectal neoplasia.

The bcl-2 oncogene plays an important role in carcinogenesis by inhibiting cell death (apoptosis). It was initially discovered in follicular B cell lymphoma with t(14,18) and subsequently found in other malignant and premalignant lesions. Alteration of the normal controls of cell proliferation is also a significant factor in the multistep process of tumorigenesis. The proliferative activity of a given lesion is commonly evaluated by MIB 1, a monoclonal antibody to Ki67 proliferation antigen. Mutation of the p53 gene is considered the most common genetic aberration in colorectal cancer. Immunohistochemical (IHC) staining expression of bcl-2, Ki67, and p53 was retrospectively investigated in a series of 52 colorectal carcinomas and 56 adenomas. The aim of the study was twofold: (i) to investigate any correlation between MIB 1, p53, and bcl-2 immunostaining expression in colonic adenomas and carcinomas and (ii) to identify any relation between these markers and several histopathologic parameters including tumor size, pathologic stage, lymph node metastasis, angiolymphatic invasion, tumor grade, and differentiation in colon carcinomas. bcl-2 was consistently higher in adenomas than in carcinomas. There were 44 of 56 (78.6%) adenomas and 27 of 52 (51.9%) carcinomas positive for bcl-2 (P = 0.004). The mean Ki67 labeling index (LI) was 30.05 +/- 7.6 and 38.12 +/- 11.01 in adenomas and carcinomas, respectively (P = 0.0001). p53 was significantly higher in carcinomas (35 of 52 [67.3%]) than in adenomas (18 of 56 [32.1%]) (P = 0.0004). Expression of bcl-2 in carcinoma was associated with a lower p53 levels and lower mean Ki67 LI and with favorable histopathologic parameters. Higher p53 and Ki67 values were associated with prognostically poor histopathologic features (differentiation and Duke's stage). We conclude that, in contrast to p53 and Ki67, bcl-2 oncoprotein expression is probably an early step in the process of colon carcinogenesis, and its expression may be associated with favorable pathologic parameters. Furthermore, an inverse relation exists between p53 and Ki67, and bcl-2 IHC expression in colonic neoplasia. Evaluation of bcl-2, p53, and Ki67 IHC expression in colonic carcinoma may be of value in predicting the clinical course in these patients.

Adenoma↗
PubMed2000

Bayesian inference for kappa from single and multiple studies.

Cohen's kappa coefficient is a widely popular measure for chance-corrected nominal scale agreement between two raters. This article describes Bayesian analysis for kappa that can be routinely implemented using Markov chain Monte Carlo (MCMC) methodology. We consider the case of m > or = 2 independent samples of measured agreement, where in each sample a given subject is rated by two rating protocols on a binary scale. A major focus here is on testing the homogeneity of the kappa coefficient across the different samples. The existing frequentist tests for this case assume exchangeability of rating protocols, whereas our proposed Bayesian test does not make any such assumption. Extensive simulation is carried out to compare the performances of the Bayesian and the frequentist tests. The developed methodology is illustrated using data from a clinical trial in ophthalmology.

Bayes Theorem↗
PubMed2000

Should the age specific prostate specific antigen cutoff for prostate biopsy be higher for black than for white men older than 50 years?

PURPOSE: Investigators who have examined age specific reference ranges recommend a higher prostate specific antigen (PSA) cutoff for biopsy for black than for white men older than 50 years. We controlled for PSA to determine whether age specific reference range cutoffs for diagnosis defined by the Walter Reed Army Medical Center group (Walter Reed group) would improve the disproportionate prostate cancer prognosis between black and white men. MATERIALS AND METHODS: We studied 651 consecutive patients who underwent radical prostatectomy at Wayne State University between 1991 and 1995 with a mean followup of 34 months (range 1.5 to 75). Log rank tests were used to determine the homogeneity of survival functions between black and white men with similar PSA ranges, and between groups defined by age specific PSA reference ranges for each race. RESULTS: Disease stage and grade were similar or worse in black men for any PSA range, and biochemical disease-free survival was similar or worse within each range. Black men had a higher percentage of high grade prostate cancer than white men 60 to 69 years old who would not have undergone biopsy using the Walter Reed group proposed PSA cutoff. CONCLUSIONS: Black men have similar or worse prostate cancer severity and outcome than white men with similar PSA ranges. Using age specific reference ranges for the PSA test defined by the Walter Reed group, black men have worse outcome than white men after radical prostatectomy. Therefore, we recommend that the PSA cutoff for biopsy should not be higher for black men at any age range.

Black or African American↗
PubMed2000

Prenatal diagnosis of beta-thalassaemia and other haemoglobinopathies in India.

This paper reports prenatal diagnosis of 787 fetuses of beta-thalassaemia and other haemoglobinopathies in Indian high-risk communities. DNA based diagnosis was offered in the first, as well as the second trimester, in 489 pregnancies (with five twins) on fetal tissues such as chorionic villus (CV) and amniocytes using the amplification refractory mutation system (ARMS) and restriction fragment length polymorphism (RFLP) techniques. Two hundred and ninety-two women (with one twin), who either presented late in the second trimester or whose DNA diagnosis was not informative, were offered prenatal diagnosis using globin chain synthesis (GCS) on fetal blood cells. Maternal contamination of fetal DNA was ruled out by variable number tandem repeat (VNTR) analysis using sites in four different genes (Apo-B, D1S-80, Ig-JH and Ha-ras), while contamination of fetal blood was checked by a particle size distribution channelyzer. Using both techniques we were able to offer complete diagnosis in 99.8% cases. Out of 494 fetuses tested by DNA analysis, 135 were found to be normal, 201 were carriers, whereas 146 were affected. Out of 293 fetuses analysed by GCS, 215 were unaffected and 71 were affected. In this study, both fetuses were tested in twin pregnancies, of which three required selective termination of one fetus. Because of social, religious taboos and family influences, genetic counselling was found to be an important guideline for couples selecting options for prenatal diagnosis. Our experience suggests that because of late presentation by many couples to the diagnostic centres, in developing countries like India, both the techniques of DNA analysis and GCS should be made available at major referral centres for maximum benefit to couples.

Amniocentesis↗
PubMed2000

Validity of mechanism of gene transfer in the process called conjugation in bacteria.

We have attempted a new evaluation of the process of conjugation in bacteria, because of some basic dissimilarities observed between this and that of eukaryotes, or plants and animals. Reference donor and recipient strains, widely used to prove conjugation in bacteria, were chosen; addition of DNase during the conjugation process, led to an unexpected but highly reproducible increase in the transconjugant colony counts (TCC; ca. > or = 1 log), when compared with that of the controls without DNase. Transconjugants were also obtained when the same live donors were substituted with the UV-killed ones although the TCC was very low initially. Contrarily, donors treated with DNA-intercalating agents, e.g. acridine orange or ethidium bromide, resulted in a complete failure to produce transconjugants. There was a quantitative relationship between the DNase used on donors and levels of DNA sugars/nucleotides/DNA, which possibly resulted from interaction between the DNase and DNA being present/produced on the donor surface. This may be indicative of what may actually happen in the donor-recipient mixtures in the conjugation test proper, where the recipient DNase may activate a donor DNA production cycle. The evidences presented did not suggest that the donor DNA in the conjugation process is actually vestibuled through any intercellular conjugation passages, and is susceptible to the action of DNase or the intercalating dyes.

Animals↗
PubMed1999

Prevalence of the inactivating 609C-->T polymorphism in the NAD(P)H:quinone oxidoreductase (NQO1) gene in patients with primary and therapy-related myeloid leukemia.

NAD(P)H:quinone oxidoreductase (NQO1) converts benzene-derived quinones to less toxic hydroquinones and has been implicated in benzene-associated hematotoxicity. A point mutation in codon 187 (Pro to Ser) results in complete loss of enzyme activity in homozygous subjects, whereas those with 2 wild-type alleles have normal activity. The frequency of homozygosity for the mutant allele among Caucasians and African Americans is 4% to 5% but is higher in Hispanics and Asians. Using an unambiguous polymerase chain reaction (PCR) method, we assayed nonmalignant lymphoblastoid cell lines derived from 104 patients with myeloid leukemias; 56 had therapy-related acute myeloid leukemia (t-AML), 30 had a primary myelodysplastic syndrome (MDS), 9 had AML de novo, and 9 had chronic myelogenous leukemia (CML). All patients had their leukemia cells karyotyped. Eleven percent of the t-AML patients were homozygous and 41% were heterozygous for the NQO1 polymorphism; these proportions were significantly higher than those expected in a population of the same ethnic mix (P =.036). Of the 45 leukemia patients who had clonal abnormalities of chromosomes 5 and/or 7, 7 (16%) were homozygous for the inactivating polymorphism, 17 (38%) were heterozygous, and 21 (47%) had 2 wild-type alleles for NQO1. Thus, NQO1 mutations were significantly increased compared with the expected proportions: 5%, 34%, and 61%, respectively (P =.002). An abnormal chromosome no. 5 or 7 was observed in 7 of 8 (88%) homozygotes, 17 of 45 (38%) heterozygotes, and 21 of 51 (41%) patients with 2 wild-type alleles. Among 33 patients with balanced translocations [14 involving bands 11q23 or 21q22, 10 with inv(16) or t(15;17), and 9 with t(9;22)], there were no homozygotes, 15 (45%) heterozygotes, and 18 (55%) with 2 wild-type alleles. Whereas fewer than 3 homozygotes were expected among the 56 t-AML patients, 6 were observed; 19 heterozygotes were expected, but 23 were observed. The gene frequency for the inactivating polymorphism (0. 31) was increased approximately 1.4-fold among the 56 t-AML patients. This increase was observed within each of the following overlapping cohorts of t-AML patients: the 43 who had received an alkylating agent, the 27 who had received a topoisomerase II inhibitor, and the 37 who had received any radiotherapy. Thus, the frequency of an inactivating polymorphism in NQO1 appears to be increased in this cohort of myeloid leukemias, especially among those with t-AML or an abnormality of chromosomes 5 and/or 7. Homozygotes and heterozygotes (who are at risk for treatment-induced mutation or loss of the remaining wild-type allele in their hematopoietic stem cells) may be particularly vulnerable to leukemogenic changes induced by carcinogens.

Alleles↗
PubMed1999

Role of radical prostatectomy in patients with prostate cancer of high Gleason score.

BACKGROUND: The routine use of serum prostate-specific antigen (PSA) testing combined with digital rectal examination has lowered tumor volume and clinical-pathological stage of men undergoing radical prostatectomy. Therefore, we may identify more men with poorly differentiated tumors of early clinical stage. In order to identify those who may benefit from radical prostatectomy, we evaluated known prognostic variables in patients with prostate cancer of high Gleason score (8-10). METHODS: Of 652 patients who underwent a radical prostatectomy as monotherapy for clinically localized prostate cancer between March 1991-December 1995, 84 patients with prostatectomy specimen Gleason score 8-10 tumors were identified. Clinical-pathological data were obtained from our prostate cancer database. Gleason score, PSA level, margin status, pathologic stage, and tumor volume were analyzed as general prognostic variables for disease-free survival (DFS). Follow-up ranged from 13-84 months (median, 36.2). Biochemical recurrence was defined as a postoperative PSA elevation greater than 0.4 ng/ml. RESULTS: The DFS for patients with Gleason score 8-10 and pathologically organ-confined disease was 62.5%. DFS was 56.2% for patients with PSA < or =10 ng/ml, compared to 19.2% for patients with serum PSA >10 ng/ml (P = 0.009). Patients with nonspecimen-confined disease (positive margins) had a DFS rate of 26.6% vs. 55% for patients with specimen-confined disease (negative margins) (P = 0.009). On multivariable analysis, only preoperative PSA < or =10 ng/ml (P = 0.02) and surgical margin status (P = 0.04) were significant predictors of DFS. CONCLUSIONS: Surgical margin status and preoperative serum PSA level are independent predictors of DFS for patients with high Gleason score prostate cancer treated by radical prostatectomy as monotherapy. Patients with poorly differentiated prostate cancer treated surgically at an early stage can have a favorable prognosis, especially if negative surgical margins are obtained. A preoperative serum PSA level < or =10 ng/ml carries the greatest likelihood of achieving prolonged DFS in this group of patients.

Adult↗
PubMed1999

Outcome of palliative urinary diversion in the treatment of advanced malignancies.

BACKGROUND: It is unclear whether palliative endourologic or percutaneous urinary diversion in the treatment of advanced cancer provides significant improvement in quality or duration of life. The purpose of this study was to evaluate survival and performance status after endourologic palliative urinary diversion in patients with advanced malignancy and to compare the results for different malignancies. METHODS: One hundred three patients with advanced malignancies underwent palliative urinary diversion (stent or nephrostomy) between 1986 and 1997. Ninety-two patients and 11 patients had bilateral and unilateral obstruction, respectively. Indications, complications, performance status after diversion, and survival for patients with different malignancies were identified and compared. A modified Karnofsky performance scale (KPS) was used for assessment of physical performance. A scale of 0-4 was used: 0) hospitalized until death; 1) bedridden at home, severe pain despite analgesia; 2) moderate disability, moderate pain despite analgesia; 3) mild disability, pain free with medication; and 4) normal. RESULTS: The mean age of patients was 68 years. The mean pre- and postoperative creatinine levels were 6 mg/dL and 3.3 mg/dL, respectively (P < 0.0001). The median survival and days of hospitalization were 112 and 45, respectively. The median postdiversion KPS score was 2 (range, 0-4), and 15% of patients never left the hospital. Overall, 51% required secondary percutaneous procedures, and 68.4% had complications (minor, 63%; major, 5.4%). CONCLUSIONS: Most patients with advanced cancers had poor performance status and survival after diversion. Eighty six percent had cancer-related symptoms despite the diversion. The average survival was 5 months, 50% of which was spent in the hospital. Primary endourologic procedures had a high failure rate, and additional procedures were required.

Aged↗
PubMed1999

Should African-American men be tested for prostate carcinoma at an earlier age than white men?

BACKGROUND: There have recently been challenges to testing high risk populations, i.e., African-American men younger than 50 years, for prostate carcinoma (PCa). The mortality rate of patients with PCa between ages 40 and 60 years is nearly 3 times greater among African-American men (AAM) compared with white men (WM). The literature in support of testing AAM at an earlier age than WM is sparse. Therefore, the authors present clinical and histologic data that support the testing of AAM at a younger age, utilizing data on patients with clinically localized PCa. METHODS: Examination of consecutive radical prostatectomy specimens from AAM and WM was performed from January 1991 to June 1996 among AAM and WM at Wayne State University, Harper Hospital, Detroit, Michigan. International, salvage prostatectomy, and neoadjuvant hormonal therapy patients were excluded, as were patients with lymph node metastasis. The authors examined biochemical recurrences of PCa in this cohort of men treated from January 1991 through December 1995. Univariate analysis of contingency tables was performed, using chi-squared-tests to assess the correlation between stage and race after stratification of patients by age group. Biochemical recurrence was analyzed using the Kaplan-Meier method and the log rank test. RESULTS: The authors examined radical prostatectomy specimens from 759 patients and biochemical recurrence outcome of 655 patients. AAM patients ages 50-69 years had higher prostate specific antigen levels, worse Gleason scores, more advanced stages of disease, and a higher recurrence rate. However, among men ages 70-79 years, there was no difference in these parameters between AAM and WM. Among men ages 40-49 years, a larger sample size is necessary to make meaningful comparisons. CONCLUSIONS: Data on the outcomes of men treated for clinically localized PCa demonstrated more advanced disease and more frequent recurrence among young AAM than among WM, young and of advanced age. These differences in disease severity and recurrence, in addition to the disproportionate mortality among young AAM, are strong evidence that AAM should be tested for PCa at an earlier age than WM.

Black or African American↗
PubMed1999

Tumor angiogenesis in vulvar squamous cell carcinoma.

OBJECTIVE: Angiogenesis has been shown to correlate positively with the presence of metastatic disease in some tumors, but has not been studied in invasive vulvar squamous cell carcinoma. Fifty cases of invasive vulvar squamous cell carcinoma were studied in an effort to correlate angiogenesis with stage, survival, and pattern of invasion. METHODS: These patients were diagnosed between 1987 and 1993. Microvessels were identified immunohistochemically using antibody to Factor VIII, and areas of greatest microvessel density associated with tumor were counted. The pattern of invasion was categorized as "spray," "pushing," or "mixed." The mean microvessel count was correlated with surgical and clinical stage, pattern of invasion, and survival. RESULTS: Mean microvessel counts in surgical stage I/II cases (31.1 +/- 7.3) were not significantly different from stage III/IV cases (26.3 +/- 8.6) (P = 0.089). Similarly mean microvessel counts in clinical stage I/II cases (31.6 +/- 11.9) were not significantly different from stage III/IV cases (27.0 +/- 8.7) (P = 0.198). Seventeen patients who died of disease had mean counts of 26.1 +/- 6.4, while 21 patients alive with or without evidence of disease had counts of 31.1 +/- 10.8 (P = 0.087). Mean microvessel counts did not vary significantly with the spray pattern (30.1 +/- 8. 7), pushing pattern (31.4 +/- 12.9), or mixed pattern of invasion (31.4 +/- 12.9) (P = 0.920). CONCLUSIONS: Tumor angiogenesis in vulvar squamous cell carcinoma does not correlate positively with stage, survival, or pattern of invasion and cannot be used as a prognostic indicator.

Adult↗
PubMed1999

Population-based study of pelvic lymph node positivity in clinically localized prostate cancer: a study comparing African Americans and whites.

OBJECTIVES: To evaluate the correlation between race and lymph node metastasis for prostate cancer by analyzing which preoperative parameters may predict lymph node status in both races. METHODS: We analyzed a group of patients (552 American white men [AWM] and 423 African-American men [AAM]) who underwent radical prostatectomy plus modified pelvic lymphadenectomy between January 1991 and June 1997. Patients who received neoadjuvant radiation or hormone therapy were excluded. Univariate and multivariate analyses were performed to determine the influence of race on lymph node positivity, as well as to correlate the preoperative parameters (serum prostate-specific antigen [PSA], biopsy Gleason score, and clinical stage) with lymph node metastasis for each race separately. RESULTS: The AAM presented with significantly higher preoperative Gleason scores and PSA levels than AWM. However, comparing lymph node status by race, the difference of positivity (41 AWM [7.4% and 22 AAM [5.2%]) was not statistically significant (P = 0.16). The percentage of positive nodes was similar in both races for each subset of PSA, Gleason score, and clinical stage. Despite the statistical significance of the three preoperative parameters in univariate analysis, in multivariate analysis only PSA and Gleason score were independent predictors of positive lymph nodes. CONCLUSIONS: There is no influence of race on lymph node metastasis, despite AAM presenting with higher preoperative Gleason scores and PSA levels. In multivariate analysis, preoperative Gleason score and PSA were independent factors for positive nodes regardless of race.

Black People↗
PubMed1999

Should Gleason score 7 prostate cancer be considered a unique grade category?

OBJECTIVES: To evaluate pathologic characteristics and biochemical survival rate differences between patients with Gleason score 6 or less, 7, and 8 or more prostate cancer. METHODS: A total of 652 patients who underwent a radical prostatectomy for clinically localized prostate cancer between March 1991 and December 1995 were selected for this study. Patients who underwent neoadjuvant or adjuvant hormonal therapy or radiotherapy were excluded. Clinical and pathologic data were obtained from our prostate cancer data base. Serum prostate-specific antigen (PSA) level, pathologic stage, and disease-free survival (DFS) were analyzed between the three Gleason score groups. RESULTS: The overall mean pretreatment serum PSA level was 12.9 ng/mL, being 8.4, 13.4, and 23 ng/mL for Gleason score 6 or less, 7, and 8 or more prostate cancers, respectively (P = 0.0001). Of patients with specimen Gleason score 6 or less, 7, and 8 or more, pathologic organ-confined disease was present in 69.4%, 43.1 %, and 9.2%, respectively (P = 0.001). Extraprostatic extension was present in 30.6%, 56.9%, and 90.8% (P = 0.0001); positive surgical margins, considered independently from the other pathologic findings, were present in 31 %, 47.6%, and 67.8% of patients with Gleason score 6 or less, 7, and 8 or more, respectively (P = 0.0001). DFS was 34.5% for patients with Gleason score 8 or more, 75% for Gleason score 7, and 91.2% for Gleason score 6 or less prostate cancers, at a median follow-up of 34.2 months (P = 0.0001). On multivariable analysis, after adjusting for serum PSA level (10 or less or more than 10 ng/mL) and pathologic stage, Gleason score (6 or less, 7, 8 or more) remained a statistically significant predictor of DFS (P = 0.0001). CONCLUSIONS: Patients with Gleason score 7 prostate cancer should be considered a specific prognostic category. We believe that this distinction is critical to obtain more reliable results from prostate cancer analyses about prognosis of patients treated with curative intent.

Disease-Free Survival↗
PubMed1999

Lymph node size does not correlate with the presence of prostate cancer metastasis.

OBJECTIVES: To determine whether lymph node size is a surrogate marker for lymph node metastasis. METHODS: We reviewed 980 patients who underwent radical retropubic prostatectomy with bilateral pelvic lymph node dissection for clinically localized prostate cancer, of whom 63 had lymph node metastases. A comparable group of patients with prostate cancer undergoing radical prostatectomy who did not have lymph node involvement was identified using the following parameters: serum prostate-specific antigen level, clinical and pathologic stage, and pre- and postoperative Gleason score. The axial and longitudinal dimensions of the nodes from patients with and without metastases were analyzed to assess the significance of lymph node size in predicting the presence of metastases. All patients had negative preoperative computed tomography (CT) and bone scans. Of the 63 patients with lymph node metastases, 48 had tissue available for measuring the dimensions of the lymph nodes. RESULTS: A total of 76 metastatic and 92 negative lymph nodes were identified from the patients with and without metastatic nodes, respectively. The mean nodal longitudinal size was 1.65 cm (range 0.2 to 6.5) and 3.50 cm (range 0.5 to 9) for positive and negative nodes, respectively (P = 0.0001). The mean axial nodal size was 0.8 cm (range 0.2 to 3.2) and 1.0 cm (range 0.2 to 2.2) for positive and negative lymph nodes, respectively. In 56 metastatic nodes (74%), the axial size was less than 1 cm and in 20 (26%) less than 5 mm. CONCLUSIONS: Lymph node size should not be used as a surrogate for the presence of lymph node metastases. Although no patient had enlarged lymph nodes by CT scan criteria (greater than 1.5 cm), 6 (8%) of 48 and 19 (12%) of 48 patients with and without lymph node metastases, respectively, had nodes with an axial dimension greater than 1.5 cm.

Aged↗
PubMed1999

Correlation of bcl-2 oncoprotein immunohistochemical expression with proliferation index and histopathologic parameters in colorectal neoplasia.

Thebcl-2oncogene plays an important role in carcinogenesis by inhibiting cell death (apoptosis). It was initially discovered in follicular B cell lymphoma with t(14,18), and subsequently found in other malignant and premalignant lesions. Alteration of the normal controls of cell proliferation is also a significant factor in the multistep process of tumorigenesis. The proliferative activity of a given lesion is commonly valuated by MIB1, a monoclonal antibody to Ki67 proliferation antigen. Immuno-histochemical (IHC) staining expression of bcl-2 and Ki67 was retrospectively investigated in a series of 52 colorectal carcinomas and 56 adenomas according to the avidin-biotin-complex method. The aim of the study was twofold: 1) to investigate any correlation between MIB1 and bcl-2 immunostaining expression in colonic adenomas and carcinomas, 2) to identify any relationship between either marker and several histopathologic parameters including tumor size, pathologic stage, lymph node metastasis, angio-lymphatic invasion, tumor grade and differentiation in colon carcinomas. Bcl-2 was consistently higher in adenomas than in carcinomas. There were 44/56 (78.6%) adenomas, and 27/52 (51.9%) carcinomas positive for bcl-2 (p=0.004). The mean Ki67 labeling index (LI) was 30.05+/-7.6 and 38.12+/-11.01 in adenomas and carcinomas, respectively (p=0.0001). Expression of bcl-2 in carcinoma was significantly associated with a lower mean Ki67 LI and with favorable histopathologic parameters. We conclude that bcl-2 oncoprotein expression is probably an early step in the process of colon carcinogenesis, and its expression may be associated with a favorable clinical course. Furthermore, an inverse relationship exists between bcl-2 and Ki67 in colonic neoplasia. Evaluation of bcl-2 and Ki67 IHC expression in colonic carcinoma should be performed prospectively to determine if their expression is of value in predicting the clinical course in these patients.

Adenocarcinoma↗