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E D Crawford

Publications and source records attributed to E D Crawford.

At least 19 recordsLinked to original sources
PubMed2000

The use of artificial intelligence technology to predict lymph node spread in men with clinically localized prostate carcinoma.

BACKGROUND: The current study assesses artificial intelligence methods to identify prostate carcinoma patients at low risk for lymph node spread. If patients can be assigned accurately to a low risk group, unnecessary lymph node dissections can be avoided, thereby reducing morbidity and costs. METHODS: A rule-derivation technology for simple decision-tree analysis was trained and validated using patient data from a large database (4,133 patients) to derive low risk cutoff values for Gleason sum and prostate specific antigen (PSA) level. An empiric analysis was used to derive a low risk cutoff value for clinical TNM stage. These cutoff values then were applied to 2 additional, smaller databases (227 and 330 patients, respectively) from separate institutions. RESULTS: The decision-tree protocol derived cutoff values of < or = 6 for Gleason sum and < or = 10.6 ng/mL for PSA. The empiric analysis yielded a clinical TNM stage low risk cutoff value of < or = T2a. When these cutoff values were applied to the larger database, 44% of patients were classified as being at low risk for lymph node metastases (0.8% false-negative rate). When the same cutoff values were applied to the smaller databases, between 11 and 43% of patients were classified as low risk with a false-negative rate of between 0.0 and 0.7%. CONCLUSIONS: The results of the current study indicate that a population of prostate carcinoma patients at low risk for lymph node metastases can be identified accurately using a simple decision algorithm that considers preoperative PSA, Gleason sum, and clinical TNM stage. The risk of lymph node metastases in these patients is < or = 1%; therefore, pelvic lymph node dissection may be avoided safely. The implications of these findings in surgical and nonsurgical treatment are significant.

Acid Phosphatase↗
PubMed2000

Phase II evaluation of cisplatin and etoposide followed by mitotane at disease progression in patients with locally advanced or metastatic adrenocortical carcinoma: a Southwest Oncology Group Study.

BACKGROUND: A previous Southwest Oncology Group study demonstrated a 30% response rate with the combination of cisplatin and mitotane in the treatment of patients with metastatic adrenocortical carcinoma. Several case reports suggested that the combination of etoposide and cisplatin may be an active regimen in this disease. Because of these reports of potential activity, the authors conducted a Phase II trial evaluating the combination of etoposide and cisplatin. Due to the lack of data regarding the objective response rates to mitotane, the authors planned to evaluate the response rate to mitotane after disease progression on etoposide and cisplatin in patients with no prior mitotane therapy. METHODS: Patients with advanced, unresectable, or metastatic adrenocortical carcinoma with objectively measurable disease or biochemical abnormalities received cisplatin, 50 mg/m(2), intravenously on Days 1 and 2, and etoposide, 100 mg/m(2), on Days 1, 2, and 3. Cycles were repeated every 21 days. At the time of disease progression, patients who had not previously received mitotane received 1000 mg orally 4 times a day along with cortisone acetate and fludrocortisone acetate. RESULTS: Of the 47 patients entered onto the study, 45 were eligible. Nine patients had received mitotane previously and 36 had not. Objective responses were noted in 11% of patients (5 of 45 patients) (95% confidence interval, 3.7-24%). The median survival was 10 months. The most common toxic effects were hematologic, gastrointestinal, and neurologic. Only 16 patients with no prior mitotane therapy went on to receive mitotane at the time of disease progression. An objective response was noted in 13% of patients (2 of 16 patients). The most common toxic effects were edema and gastrointestinal effects. CONCLUSIONS: The current study demonstrates that the combination of cisplatin and etoposide has minimal activity in advanced and metastatic adrenocortical carcinoma and other treatment strategies are warranted.

Adolescent↗
PubMed2000

Comparison of telomerase activity and GSTP1 promoter methylation in ejaculate as potential screening tests for prostate cancer.

New diagnostic tools are needed for the early detection of prostatic cancer. The molecular detection of prostate cancer cells in ejaculates was evaluated using complementary PCR-based methods. LNCaP cells, a cell line derived from prostatic carcinoma, were spiked into normal seminal ejaculates and the prostatic epithelial component of the specimens was isolated by immunomagnetic bead sorting, using a monoclonal antibody to prostate-specific membrane antigen (PSMA). Ejaculates from nine patients with a recent diagnosis of prostate cancer were processed in a similar fashion, using LNCaP-spiked aliquots as an internal positive control. Telomerase expression was evaluated by the telomeric repeat amplification protocol (TRAP) and glutathione S-transferase gene promoter (GSTP1) hypermethylation was evaluated by methylation-sensitive restriction endonuclease digestion and PCR amplification. Telomerase activity was detected in LNCaP cells recovered from normal seminal ejaculates but was not found in all nine samples from patients with prostate cancer. The sensitivity of GSTP1 analysis was similar to telomerase analysis for the detection of LNCaP cells from normal ejaculate samples but was positive in ejaculates from four out of nine patients with prostate cancer. GSTP1 DNA methylation status is more sensitive than telomerase analysis for the detection of malignant cells in seminal ejaculates from patients with prostate cancer.

DNA Methylation↗
PubMed2000

Probability of prostate cancer detection based on results of a multicenter study using the AxSYM free PSA and total PSA assays.

OBJECTIVES: The determination of the percentage of free prostate-specific antigen (%fPSA) enhances the specificity of prostate cancer (CaP) detection. This study was undertaken to assess the performance of %fPSA in differentiating benign prostate disease from CaP and to determine the CaP probability estimates using the AxSYM Free PSA and AxSYM Total PSA assays. METHODS: In this prospective study, 297 men, 50 years old or older, with a total PSA level between 4 and 10 ng/mL and a nonsuspicious digital rectal examination were enrolled at 10 clinical sites. All subjects underwent at least sextant prostate biopsies to establish the diagnosis. fPSA and total PSA (tPSA) levels were determined using the AxSYM Free PSA and AxSYM Total PSA assays. Percent fPSA values were compared with tPSA values to determine the appropriate cutoffs for prostate biopsy and to calculate the CaP probability estimates. RESULTS: The strongest predictor of CaP in a logistic regression model was %fPSA (odds ratio 2.29), which contributed significantly more than age or tPSA to the predictive model. In this study population, a %fPSA cutoff of 26.4% would have detected 96% of subjects with CaP (sensitivity) and would have eliminated 27.4% of unnecessary biopsies (specificity). CaP probability estimates ranged from 9% to 69% and increased as the %fPSA value decreased. Men with a %fPSA level of 10% or lower had a 69% probability of CaP, and men with a %fPSA level of greater than 26% had a 9% probability of CaP. CONCLUSIONS: Percent fPSA values can help differentiate CaP from benign prostate disease and reduce unnecessary biopsies in 27% of men 50 years old or older whose digital rectal examination was normal and whose tPSA level was between 4 and 10 ng/mL. A %fPSA result can assist the physician and patient in determining the probability of CaP and assessing the need for prostate biopsy.

Biopsy↗
PubMed2000

The prognostic significance of S-phase analysis in stage Ta/T1 bladder cancer. A Southwest Oncology Group Study.

OBJECTIVES: An intergroup study (SWOG 8795) comparing two forms of adjunctive therapy (immuno and chemo), bacillus Calmette-Guerin (BCG) and mitomycin C (MMC), furnished preregistration index tumors for 244 patients with superficial, papillary stage Ta/T1 TCC. These were examined by flow cytometry to learn whether DNA ploidy or proliferation (low vs high S-phase fraction (SPF) helped to predict disease recurrence or progression. METHODS: Cell cycle analysis using commercially available (Multicycle) programs was performed on 249 Ta/T1 bladder cancers. Tumor grade, available for 223 cases, was assigned by a single study pathologist. The SWOG statistical office reviewed follow-up information and other data and performed statistical analysis. RESULTS: Disease recurrence occurred in half the cases studied. The most parsimonious model predictive of recurrence included only treatment arm and tumor grade, with the MMC arm and tumor grade greater than I indicating worse prognosis (p = 0. 014). Neither ploidy nor SPF predicted recurrence-free survival or contributed prognostic information that was additive to tumor grade. Within 5 years of follow-up, disease progression or death from bladder cancer occurred for 29/223 (13%) of patients. The most parsimonious model for progression-free survival included only grade greater than I (p<0.001) and high SPF (p = 0.029) (relative risk: tumor grade, 4.3, high SPF, 1.9). CONCLUSIONS: Knowledge of tumor proliferation (low versus high SPF) contributes prognostic information about tumor progression that is additive to tumor grade.

Cell Division↗
PubMed2000

Southwest Oncology Group Study of paclitaxel and carboplatin for advanced transitional-cell carcinoma: the importance of survival as a clinical trial end point.

PURPOSE: The combination of paclitaxel and carboplatin for the treatment of advanced transitional-cell carcinoma (TCC) of the urothelium has promising activity and acceptable toxicity. The purpose of this trial was to evaluate the efficacy of this regimen in a cooperative group setting. PATIENTS AND METHODS: Twenty-nine patients with advanced TCC were treated every 21 days with paclitaxel 200 mg/m(2), administered as a 3-hour infusion, followed by carboplatin dosed to an area under the curve of 5. Prior systemic adjuvant or neoadjuvant platinum-based therapy was not permitted unless completed at least 1 year before enrollment. Patients were evaluated for response every three cycles, and follow-up was conducted to determine survival. RESULTS: Twenty-nine patients were enrolled and were assessable. Four (14%) had received prior adjuvant or neoadjuvant therapy. Node-only disease was present in 24%, and 76% of patients had extranodal disease. The median number of cycles received was five. Grade 4 toxicity consisted primarily of neutropenia (38% of patients). Neurologic toxicity was noted in 16 patients (grade 1 in four patients, grade 2 in five patients, grade 3 in six patients, and grade 4 in one patient). Six partial responses and no complete responses were noted, for a response proportion of 20.7% (95% confidence interval, 8% to 40%). Median progression-free survival time was 4 months, and overall survival time was 9 months. CONCLUSION: The combination of paclitaxel and carboplatin for the treatment of advanced TCC is reasonably well tolerated. However, a response proportion considerably lower than that previously reported was noted. In addition, the median survival time of 9 months was less than the survival time previously reported for patients treated with the combination of methotrexate, vinblastine, doxorubicin, and cisplatin. Although our results may reflect enrollment of patients with poor prognostic features, they also call into question the utility of this regimen.

Adult↗
PubMed2000

Androgen deprivation and four courses of fixed-schedule suramin treatment in patients with newly diagnosed metastatic prostate cancer: A Southwest Oncology Group Study.

PURPOSE: To assess the feasibility of administering a combination of suramin and hydrocortisone in addition to androgen deprivation in a cooperative group setting; to assess the feasibility of treatment with multiple courses of suramin; and to assess progression-free and overall survival in patients with newly diagnosed metastatic prostate cancer who underwent such treatment. PATIENTS AND METHODS: Patients with newly diagnosed metastatic prostate cancer who had adequate hematologic, hepatic, renal, neurologic, and coagulation parameters were treated by combined androgen deprivation and suramin plus hydrocortisone. Suramin was administered on a 78-day fixed dosing schedule (one cycle), and suramin treatment cycles were repeated every 6 months for a total of four cycles. The statistical design was developed on the basis of the feasibility of administering suramin, as judged by the number of patients who developed neurotoxicity of grade 3 or higher or by treatment interruption of 4 weeks or longer due to any persistent suramin-related toxicity. RESULTS: Of the 62 patients enrolled onto the study between August 1994 and January 1997, 59 were eligible and assessable for toxicity on the first cycle. Thirty-two (54%) of 59 patients received a second cycle, 13 (22%) of 59 patients received a third cycle, and only five patients (8%) received a fourth cycle. During the first cycle, 27 patients were removed from the study: 17 because of toxicity, five because of disease progression, two who had died, and three because of other reasons. There was one therapy-related death. Grade 4 toxicities were noted in 11 and three patients during first and second courses, respectively. Neurotoxicity of grade 3 or higher was observed in nine and seven patients during the first and second cycles, respectively. Fifteen patients had treatment interruptions of 4 weeks or longer. Overall, only 54% (95% confidence interval, 41% to 67%) of the patients demonstrated acceptable limits of toxicity. CONCLUSION: Suramin plus hydrocortisone and androgen deprivation has limited applicability in the treatment of patients with newly diagnosed metastatic prostate cancer.

Adult↗
PubMed2000

Maintenance bacillus Calmette-Guerin immunotherapy for recurrent TA, T1 and carcinoma in situ transitional cell carcinoma of the bladder: a randomized Southwest Oncology Group Study.

PURPOSE: Bacillus Calmette-Guerin (BCG) immunotherapy has been widely accepted as the optimal treatment for carcinoma in situ and high grade superficial transitional cell carcinoma. However, controversy remains regarding the role of maintenance therapy, and its long-term effect on recurrence and progression. MATERIALS AND METHODS: All patients in the study had transitional cell carcinoma of the bladder with carcinoma in situ or an increased risk of recurrence. The criteria for increased risk were 2 or more episodes of tumor within the most recent year, or 3 or more tumors within 6 months. At least 1 week following biopsy of carcinoma in situ and resection of any stage Ta or T1 transitional cell tumors 660 patients were started on a 6-week induction course of intravesical and percutaneous Connaught BCG. Three months following initiation of BCG induction therapy 550 consenting patients were stratified by purified protein derivative skin test and the presence of carcinoma in situ, and then randomized by central computer to receive BCG maintenance therapy (maintenance arm) or no BCG maintenance therapy (no maintenance arm). Maintenance therapy consisted of intravesical and percutaneous BCG each week for 3 weeks given 3, 6, 12, 18, 24, 30 and 36 months from initiation of induction therapy. The 384 eligible patients who were disease-free at randomization constitute the primary intent to treat analytic group because they could be followed for disease recurrence. All patients were followed for adverse effects of treatment, recurrence, disease worsening and survival. RESULTS: No toxicities above grade 3 were noted in the 243 maintenance arm patients. The policy of withholding maintenance BCG from patients with increased side effects may have diminished the opportunity to observe severe toxicity. Estimated median recurrence-free survival was 35.7 months (95% confidence interval 25.1 to 56.8) in the no maintenance and 76.8 months (64.3 to 93.2) in the maintenance arm (log rank p<0.0001). Estimated median time for worsening-free survival, defined as no evidence of progression including pathological stage T2 disease or greater, or the use of cystectomy, systemic chemotherapy or radiation therapy, was 111.5 months in the no maintenance and not estimable in the maintenance arm (log rank p = 0.04). Overall 5-year survival was 78% in the no maintenance compared to 83% in the maintenance arm. CONCLUSIONS: Compared to standard induction therapy maintenance BCG immunotherapy was beneficial in patients with carcinoma in situ and select patients with Ta, T1 bladder cancer. Median recurrence-free survival time was twice as long in the 3-week maintenance arm compared to the no maintenance arm, and patients had significantly longer worsening-free survival.

Adjuvants, Immunologic↗
PubMed2000

Use of artificial neural networks in the clinical staging of prostate cancer: implications for prostate brachytherapy.

PURPOSE: This review describes two studies to evaluate artificial neural networks (ANNs) in prostate cancer staging. In the first study, an ANN was trained to identify prostate cancer patients at low risk of lymph node spread (LNS). The second study evaluated an ANN to predict capsular penetration (CP) in men with clinically localized prostate cancer. An accurate assessment of lymph node status will help identify those brachytherapy patients in whom lymphadenectomy can be avoided. The accurate prediction of CP can help determine the appropriateness of brachytherapy as a treatment option. MATERIALS AND METHODS: An ANN to predict LNS was trained and tested using a database from one institution (n = 4,133) and validated using two databases (n = 330 and n = 227) from different institutions. The clinical variables used were clinical stage (cTNM), Gleason sum, and prostate-specific antigen concentration (PSA). The ANN to predict CP was trained and validated with data from a single institution (n = 409). The variables used were age, race, PSA, PSA velocity, Gleason sum, and cTNM. RESULTS: The LNS ANN was able classify 76%, 75%, and 30% of the patients in each database as being at low risk of LNS with 98% accuracy. The CP ANN correctly identified CP in 25 (84%) of patients and produced 5 (16%) false-negative predictions. CONCLUSIONS: These preliminary results suggest that ANNs can be useful in staging prostate cancer. If sufficiently accurate ANNs can be developed and tested, they have the potential to increase the accuracy of clinical staging and thus improve treatment decisions.

Biopsy↗
PubMed2000

Minimal toxicity with 3-FAT radiotherapy of prostate cancer.

Beam radiation with three-dimensional conformal planning appears to decrease morbidity of prostate cancer therapy. The 3-field, arc technique (3-FAT) technique was designed by computer modeling to improve radiation dose to the target and minimize dispersion to nearby organs. Toxicity was studied in patients with prostate cancer. We performed a retrospective study of 168 consecutive men with prostate cancer after 3-FAT radiotherapy with a median follow-up of 24 months. All patients, treated from 1996 through 1999 at the University of Colorado had a pathological diagnosis of cancer before irradiation. Therapy was designed with a urethrogram and planning computed tomography scan. The 3-FAT was employed using noncoplanar, rotational beams, and nonuniform blocking of portals. Patients were treated to a minimal tumor dose of 74 Gy in 37 fractions. Adverse effects were investigated. Definitive radiotherapy was given to 80% of the group, and 58% received total androgen blockade. 3-FAT produced favorable dose distributions for the rectum, bladder, femoral heads, and base of the penis. Patients routinely report minimal dysuria and frequency during treatment. There were minimal urinary complaints after irradiation and no proctitis, diarrhea, incontinence, or change in potency as a result of radiotherapy. The 3-FAT represents a technical improvement in the treatment of prostate cancer by minimizing radiation delivered to adjacent critical structures. There were minimal side effects to the rectum, bladder, and penis base despite high doses to the prostate and seminal vesicles. The large percentage of patients with preliminary prostate-specific antigen values below 1.0 portends efficacy.

Aged↗
PubMed1999

Immediate hormonal therapy compared with observation after radical prostatectomy and pelvic lymphadenectomy in men with node-positive prostate cancer.

BACKGROUND: Because the optimal timing of the institution of antiandrogen therapy for prostate cancer is controversial, we compared immediate and delayed treatment in patients who had minimal residual disease after radical prostatectomy. METHODS: Ninety-eight men who underwent radical prostatectomy and pelvic lymphadenectomy and who were found to have nodal metastases were randomly assigned to receive immediate antiandrogen therapy, with either goserelin, a synthetic agonist of gonadotropin-releasing hormone, or bilateral orchiectomy, or to be followed until disease progression. The patients were assessed quarterly during the first year and then semiannually. RESULTS: After a median of 7.1 years of follow-up, 7 of 47 men who received immediate antiandrogen treatment had died, as compared with 18 of 51 men in the observation group (P=0.02). The cause of death was prostate cancer in 3 men in the immediate-treatment group and in 16 men in the observation group (P<0.01). At the time of the last follow-up, 36 men in the immediate-treatment group (77 percent) and 9 men in the observation group (18 percent) were alive and had no evidence of recurrent disease, including undetectable serum prostate-specific antigen levels (P<0.001). In the observation group, the disease recurred in 42 men; 13 of the 36 who were treated had a complete response to local treatment or hormonal therapy (or both), 16 died of prostate cancer, and 1 died of another disease. The remaining men in this group were alive with progressive disease at the time of the last follow-up or had had a recent relapse. Except for the treatment group (immediate therapy or observation), no clinical or histologic characteristic significantly influenced the outcome. CONCLUSIONS: Immediate antiandrogen therapy after radical prostatectomy and pelvic lymphadenectomy improves survival and reduces the risk of recurrence in patients with node-positive prostate cancer.

Aged↗
PubMed1999

Efficiency of prostate-specific antigen and digital rectal examination in screening, using 4.0 ng/ml and age-specific reference range as a cutoff for abnormal values.

BACKGROUND: The purpose of this study was to examine the diagnostic efficiency of prostate-specific antigen (PSA) and digital rectal examination (DRE) testing when using either 4.0 ng/ml or an age-specific reference range (ASRR) as an abnormal cutoff PSA value. METHODS: Between 1992-1995, 116,073 men, aged 40-79 years, were screened during Prostate Cancer Awareness Week. When using a 4.0-ng/ml cutoff PSA value, 22,014 had either an abnormal PSA, an abnormal DRE, or both. When using an ASRR cutoff PSA value, 17,561 had either an abnormal PSA, an abnormal DRE, or both. The positive predictive value (PPV), sensitivity, and specificity of PSA, DRE, and combined PSA and DRE tests were evaluated. RESULTS: When using a 4.0-ng/ml cutoff PSA value, the PPVs of abnormal PSA alone, abnormal DRE alone, and combined abnormal PSA and DRE tests were 27.7%, 17.7%, and 56.0%, respectively. Sensitivities were 34.9%, 27.1%, and 38.0%, respectively. Specificities were 63.1%, 49.0%, and 87.9%, respectively. When using an ASRR cutoff PSA value, the PPVs of each category were 31.8%, 20.8%, and 63.7%, respectively. Sensitivities were 27.1%, 41.0%, and 31.8%, respectively. Specificities were 75.0%, 32.8%, and 92.2%, respectively. The PPVs of the PSA test were higher than those of the DRE. The PPVs of combined tests were highest when using either a 4.0-ng/ml cutoff PSA value or an ASRR cutoff PSA value (all P < 0.001). When using an ASRR, the PPVs of PSA, DRE, and combined tests were higher than those when using a 4.0-ng/ml without statistical significance (all P > 0.05). Sensitivity of PSA when using an ASRR was lower than when using 4.0 ng/ml. CONCLUSIONS: Significantly higher PPVs indicated that utilizing both a PSA test and a DRE is most effective in screening for the early detection of prostate cancer. Although higher PPVs when using an ASRR cutoff PSA value suggested fewer unnecessary biopsies, lower sensitivities resulted in fewer cancers detected. Thus, we recommend that the combination of a PSA test with a cutoff value of 4.0 ng/ml and a DRE should continue to be utilized in the screening programs.

Adult↗
PubMed1999

Endocrine effects, efficacy and tolerability of a 10.8-mg depot formulation of goserelin acetate administered every 13 weeks to patients with advanced prostate cancer.

OBJECTIVE: To determine the endocrine effects, efficacy and tolerability of a 10.8-mg depot formulation of Zoladextrade mark (goserelin acetate, Zeneca Pharmaceuticals, Wilmington, Delaware, USA), a luteinizing hormone-releasing hormone agonist analogue, when administration was extended from every 12 weeks to every 13 weeks in patients with advanced prostate cancer. PATIENTS AND METHODS: Between July 1995 and May 1996, 59 patients with either locally advanced (T3 or T4) or metastatic prostate cancer were enrolled in an open-label, multicentre trial. Primary efficacy endpoints were testosterone measurements, and assessments of prostate specific antigen (PSA) response, subjective and objective response. Quality of life (QoL) was a secondary efficacy endpoint. RESULTS: Mean testosterone concentrations decreased to < 0.3 microgram/L by week 4 and remained so for the duration of treatment. There were no statistically significant differences in mean testosterone levels between weeks 12 and 13, or weeks 25 and 26. Serum testosterone suppression was adequate in all 58 evaluable patients at week 13, and 51 of 52 (98%) patients at week 26. Of the 58 evaluable patients, 52 (90%) had a PSA response. A subjective response was recorded for six of 11 evaluable patients. Of 58 patients evaluable for objective response, 46 (79%) had a partial response, three (5%) had stable disease and nine (16%) had objective progression. Except for a significant (P=0.014) decrease in overall sexual interest, QoL was unchanged during therapy. The most common side-effects, regardless of causality, were hot flushes (67%), pain (31%) and pelvic pain (22%). Mild injection-site complaints occurred with only three of 221 (1.4%) depot injections. CONCLUSIONS: Zoladextrade mark 10.8-mg depot, administered every 13 weeks to patients with advanced prostatic cancer, is well tolerated, provides adequate suppression of serum testosterone and produces PSA, subjective and objective responses.

Aged↗
PubMed1999

The utility of prostate-specific antigen as a surrogate marker for identification of high-risk cohorts and assessing response in chemoprevention trials.

Serum prostate-specific antigen (PSA) is the most important tumor marker in oncology practice. It may assume a similar role in chemoprevention strategies. It is a simple and reproducible blood test that can both identify a high-risk cohort and provide meaningful information regarding the response to intervention. A wealth of information is available regarding the relationship of PSA to age, race and velocity. Free and total values may serve to further define high-risk cohorts and provide a barometer for response and disease presence in chemoprevention trials.

Adult↗