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P F Schellhammer

Publications and source records attributed to P F Schellhammer.

At least 55 records · Page 3Linked to original sources
PubMed1998

PSA for outcome prediction and posttreatment evaluation following radiation for prostate cancer: do we know how to use it?

Pretreatment prostate-specific antigen (PSA) has been shown to be a powerful predictor of expected outcome after radiation for prostate cancer. Additional measures such as recursive partitioning analysis and PSA Cancer Volume calculations are further refining this useful tool to provide the greatest degree of prognostic information. The post-treatment PSA level is also being used as a means to assess therapeutic efficacy rapidly and objectively. Although no single PSA value has been shown to equate to long-term clinical tumor control consistently, consensus has been reached regarding the value of a rising PSA level as an early surrogate for tumor recurrence. Since the first introduction of PSA as a tumor marker, we have become much more comfortable with what it means, the ways it can help us, and how to use it.

Biomarkers, Tumor↗
PubMed1997

Serum levels of endothelial and neural cell adhesion molecules in prostate cancer.

BACKGROUND: Tumorigenesis and progression to metastatic disease are accompanied by changes in the expression of cell adhesion molecules (CAMs). Normally expressed CAMs, such as E-cadherin, are lost, while others, i.e., ICAM-1, VCAM-1, NCAM, and E-selectin, are altered and overexpressed in progressive disease and metastases. Abnormal levels of these latter CAMs have been observed in melanoma and carcinomas of the colon and breast, and NCAM is overexpressed in small-cell lung carcinoma (SCLC). The objective of this study was to determine if serum levels of ICAM-1, VCAM-1, NCAM, and E-selectin could differentiate patients with benign prostate hypertrophy (BPH) from those with prostate carcinoma (CaP) and identify prostate cancers with high potential for progression to metastatic disease. METHODS: Serum levels of these CAMs were determined by ELISA in serum from normal males and females and from patients with BPH and CaP before and after treatment. Sera from patients with breast carcinoma, colon carcinoma, melanoma, and small-cell lung carcinoma were also evaluated, as soluble CAMs have been reported to be elevated in these cancer patients. RESULTS: ICAM-1 levels were elevated in sera from patients with breast carcinoma (P = 0.0004) and melanoma (P = 0.0001). VCAM-1 levels were elevated in sera from patients with colon carcinoma (P = 0.0001). NCAM levels were elevated in the sera of patients with SCLC (P = 0.0001). Normal levels of ICAM-1, E-selectin, and NCAM were found in both BPH and pretreatment CaP patients. Median NCAM levels in hormone-refractive CaP patients were significantly greater than in BPH (P = 0.0005) and CaP patients with pathologically determined organ-confined (P = 0.0014) or nonorgan-confined disease (P = 0.0385). VCAM-1 levels were significantly elevated in both BPH patients (P = 0.0002) and CaP patients (P = 0.0002) when compared with levels for normal age-matched donors. None of the CAMs were found to offer an advantage over prostatic-specific antigen (PSA) for monitoring CaP patients following definitive radiotherapy, radical prostatectomy, or hormonal therapy. CONCLUSIONS: The results of this study indicate that serum ICAM-1, VCAM-1, NCAM, and E-selectin are not clinically useful biomarkers for differentiating CaP from BPH, for predicting progression, for identifying metastatic potential, or for monitoring treatment.

Adult↗
PubMed1997

Calcium signaling in prostate cancer cells: evidence for multiple receptors and enhanced sensitivity to bombesin/GRP.

BACKGROUND: Cellular calcium is an important second messenger for growth regulation. We sought to identify potentially important receptors on prostate tumor cells by screening over 20 agonists for their ability to increase intracellular free calcium ([Ca2+]i) in several human prostate tumor cell lines. METHODS: Intracellular calcium mobilization was detected using fura-2. RESULTS: We found bombesin, GRP, ATP/UTP, lysophosphatidic acid, thrombin, endothelin, histamine, and bradykinin increased [Ca2+]i in the advanced tumor cell lines DU-145, PC3, and PPC-1. Bombesin failed to elevate [Ca2+]i in an immortalized human prostate cell line. Rank-order of potency studies suggested the presence of P2U nucleotide receptors for ATP/UTP on prostate epithelial cells. Potency studies also revealed GRP > > bombesin > > neuromedin B at elevating [Ca2+]i in responding tumor cells. CONCLUSIONS: These findings indicate that androgen independent prostate tumor cell lines express multiple receptors capable of elevating intracellular calcium, and suggest that GRP receptors may be selectively expressed and/or coupled to calcium signaling during prostate tumor progression. Calcium sensitive cellular events may therefore contribute to the progression of prostate cancer.

Bombesin↗
PubMed1997

Determination of the "reflex range" and appropriate cutpoints for percent free prostate-specific antigen in 413 men referred for prostatic evaluation using the AxSYM system.

OBJECTIVES: Prostate-specific antigen (PSA) exists in the serum in two clinically important molecular forms: free PSA and PSA complexed to alpha 1-antichymotrypsin. Total PSA approximates the sum of the free and complexed forms. Preliminary investigations have illustrated the potential benefits of using percent free PSA to enhance the clinical utility of PSA in distinguishing benign prostate disease from prostate cancer. The current study defines the optimal range of total PSA for measuring percent free PSA (reflex range) and generates appropriate cutpoints for percent free PSA within this range. METHODS: A total of 413 patients, 225 (54%) with benign prostate disease (mean age, 67 years) and 188 (46%) with prostate cancer (mean age, 66 years), who had PSA values between 2.0 and 20.0 ng/mL participated in the investigation. All patients underwent a sextant biopsy to establish the diagnosis. The serum specimens were assayed with the AxSYM PSA assay (total PSA) and AxSYM Free PSA assay (Abbott Laboratories; Abbott Park, IL). Percent free PSA was calculated for all patients. Receiver operating characteristic (ROC) curves were generated for various ranges of total PSA to determine the reflex range that maximized the increase in sensitivity and specificity of percent free PSA over total PSA. Within the optimal range, the ROC curves were utilized to generate cutpoints for percent free PSA to be used in clinical practice. RESULTS: The appropriate reflex range for the utility of percent free PSA was 3.0 to 10.0 ng/mL. The appropriate cutpoint for percent free PSA when the total PSA value was 3.0 to 4.0 ng/mL to achieve 90% sensitivity for the detection of prostate cancer was 0.19. This approach resulted in a biopsy rate of 73% and a cancer detection rate of 44% in men with a total PSA value between 3.0 and 4.0 ng/mL. The appropriate cutpoint for percent free PSA when the total PSA value was 4.1 to 10.0 ng/mL to ensure 95% sensitivity for detection of prostate cancer was 0.24. Within the range of 4.1 to 10.0 ng/mL, this approach resulted in 13% fewer negative biopsies and failure to detect 5% of the cancers. CONCLUSIONS: Percent free PSA should be utilized in patients with a total serum PSA value between 3.0 and 10.0 ng/mL. In patients with a total PSA value between 3.0 and 4.0 ng/mL, percent free PSA enhanced the detection of prostate cancer (improving sensitivity). In patients with a total PSA concentration ranging from 4.1 to 10.0 ng/mL, negative biopsies were eliminated (improving specificity).

Adult↗
PubMed1997

Additional bacillus Calmette-Guérin therapy for recurrent transitional cell carcinoma after an initial complete response.

OBJECTIVES: To determine the success of additional bacillus Calmette-Guérin (BCG) therapy for transitional cell carcinoma recurring after a complete response (CR) to the initial treatment course of BCG. METHODS: All patients treated with BCG with a minimum follow-up of 5 years were reviewed to identify complete responders who subsequently recurred and received additional BCG therapy. The duration of initial response and the incidence and duration of a second CR were recorded. RESULTS: Of 11 patients with an initial CR to a 6-week course of BCG, 9 (82%) achieved a second CR and 5 of the 9 (42%) maintained tumor-free status beyond 5 years of follow-up (median 87 months, range 64 to 110). Patients who again recurred after the second CR did not benefit from further BCG therapy. CONCLUSIONS: A repeat course of BCG is a reasonable option of therapy for transitional cell carcinoma that has recurred after a CR to a prior course of BCG. Careful monitoring by cytology, cystoscopy, and biopsy is mandatory to direct nonresponders to prompt alternative therapy and to ensure continued disease-free status among responders.

Adjuvants, Immunologic↗
PubMed1997

Separated pyelocolocutaneous diversion after bilateral ureterectomy and radical cystectomy for transitional cell carcinoma.

OBJECTIVES: To report a technique for excision of bilateral ureteral transitional cell carcinoma which preserves renal function and provides ready access for endoscopic follow-up and therapy of the renal pelvis. METHODS: The operative procedure of bilateral ureterectomy with construction of a separated pyelocolocutaneous diversion utilizing transverse colon is described and the clinical course of 4 patients is reported. RESULTS: All 4 patients maintained excellent renal function and normal electrolytes. Conduit urine cytologic studies and renal pelvis endoscopic examinations have remained normal. Parastomal herniation was the most frequently observed postoperative complication. CONCLUSIONS: This approach is well suited for the treatment of bilateral ureteral transitional cell carcinoma. Long-term complications are minimal and renal function is preserved. Periodic endoscopic visualization of each renal pelvis with resection and fulguration and/or instillation of immunotherapeutic or chemotherapeutic agents for recurrent renal pelvic lesions is readily accomplished.

Aged↗
PubMed1997

Clinical benefits of bicalutamide compared with flutamide in combined androgen blockade for patients with advanced prostatic carcinoma: final report of a double-blind, randomized, multicenter trial. Casodex Combination Study Group.

OBJECTIVES: To compare the efficacy and tolerability of bicalutamide and flutamide, each combined with luteinizing hormone-releasing hormone analogue (LHRH-A) therapy, in patients with metastatic (Stage D2) prostate cancer. METHODS: This was a randomized, double-blind (for antiandrogen therapy), multicenter study with a two-by-two factorial design. Eight hundred thirteen patients were allocated 1:1 to bicalutamide (50 mg once daily) and flutamide (250 mg three times daily) and 2:1 to goserelin acetate (3.6 mg every 28 days) and leuprolide acetate (7.5 mg every 28 days). RESULTS: The median times to progression and death were 97 and 180 weeks for the bicalutamide plus LHRH-A group compared with 77 and 148 weeks for the flutamide plus LHRH-A group. The hazard ratio for time to progression for bicalutamide plus LHRH-A to flutamide plus LHRH-A was 0.93 (95% confidence interval [CI] 0.79 to 1.10, P = 0.41) and that for survival time was 0.87 (95% CI 0.72 to 1.05, P = 0.15). The therapies were generally well tolerated. The most common adverse event in the two groups was hot flashes. The incidence of hematuria was significantly higher for the bicalutamide plus LHRH-A group than for the flutamide plus LHRH-A group (12% versus 6%, P = 0.007), but no patient withdrew from therapy because of hematuria. There was a significantly (26% versus 12%, P < 0.001) higher incidence of diarrhea and more withdrawals for diarrhea (25 patients versus 2) for the flutamide plus LHRH-A group relative to the bicalutamide plus LHRH-A group. CONCLUSIONS: With a median follow-up time of 160 weeks, the combination of bicalutamide plus LHRH-A was well tolerated and had equivalent time to progression and survival compared with flutamide plus LHRH-A. Treatment with bicalutamide plus LHRH-A resulted in longer median survival than treatment with flutamide plus LHRH-A.

Adult↗
PubMed1997

Improved detection of recurrent bladder cancer using the Bard BTA stat Test.

OBJECTIVES: To evaluate the BTA stat Test in the detection of recurrent bladder cancer. METHODS: Sensitivity and specificity were determined using frozen voided urine samples from patients with recurrent bladder cancer, volunteers, patients with nonurologic conditions, and patients with a history of bladder cancer but free of disease. Results of cytology and the original BTA Test were compared with the sensitivity of the BTA stat Test in a large subgroup of the patients with cancer. RESULTS: The BTA stat Test detected 147 (67%) of 220 recurrent cancers. For those urine samples with previous cytologic and BTA Test results available, cytology had a sensitivity of 23%, the BTA Test 44%, and the BTA stat Test 58% for detection of recurrent cancer (P < 0.001, stat versus cytology). The specificity of the BTA stat Test was 72% for benign genitourinary disease and 95% in healthy volunteers. CONCLUSIONS: The BTA stat Test has high sensitivity and is significantly superior to voided urine cytologic analysis in the detection of recurrent bladder cancer.

Aged↗
PubMed1997

Prostate-specific antigen after radiation therapy. Prognosis by pretreatment level and post-treatment nadir.

After external beam radiation therapy, pretreatment prostate-specific antigen (PSA) is the most powerful predictor of outcome as measured PSA (biochemical) failure. The post-treatment nadir levels of PSA that predict best for subsequent freedom from PSA failure are debatable, and many nadir levels have been proposed as targets. Although lower nadirs generally are associated with superior outcomes, the identification of a single absolute nadir level was not selected at a recent ASTRO consensus conference. Rather, three consecutive PSA rises above the nadir, with date of failure at the midpoint between the nadir and first rise, were selected as a more useful end point for treatment failure.

Aged↗
PubMed1997

Continuous-infusion 5-fluorouracil and cisplatin for advanced/recurrent transitional cell cancer of the bladder: a Southwest Oncology Group trial.

Significant toxicities result from the use of MVAC (methotrexate, vinblastine, adriamycin, cisplatin) for advanced/ recurrent transitional cell carcinoma of the bladder (ARTCCB). An alternative regimen of 5-fluorouracil (5-FU) and cisplatin was evaluated by Southwest Oncology Group (SWOG). Thirty-eight patients with ARTCCB were treated with continuous infusion 5-FU 1,000 mg/m2/days 1-5 and cisplatin 100 mg/day 1, on a every-21-days schedule. There were two complete responses (CR) and eight partial responses (PR) among 36 eligible patients, for an overall response rate of 28% [95% confidence interval (CI) 14-45%]. Median duration of response was 6 months, and median duration of survival was 9 months. No toxic deaths occurred. Grade 4 leukopenia occurred in 5 patients. Other toxicities were mild. Only two documented infections occurred in 5 patients with neutropenia. The response rate of 28% is better than that achieved with cisplatin alone and not dissimilar to the range of response for MVAC. Toxicities were less and tolerable. This regimen will need further evaluation.

Adult↗
PubMed1997

Prostate specific antigen decreases after withdrawal of antiandrogen therapy with bicalutamide or flutamide in patients receiving combined androgen blockade.

PURPOSE: We determined whether decreases in prostate specific antigen (PSA) would occur after withdrawal of double-blinded antiandrogen therapy with flutamide or bicalutamide for clinical progression or increasing PSA concentration in patients receiving combined androgen blockade for advanced prostate cancer. MATERIALS AND METHODS: PSA concentrations were determined weekly for at least 6 weeks and then every other week for 6 weeks in 22 patients with stage D2 prostate cancer. All patients were withdrawn from antiandrogen therapy (8 flutamide and 14 bicalutamide) due to progression or an increasing PSA concentration. Objective response was evaluated before antiandrogen withdrawal and at week 12. RESULTS: In 4 of 8 patients (50%) withdrawn from flutamide and 4 of 14 (29%) withdrawn from bicalutamide serum PSA concentrations decreased by 50% or more. PSA responses after withdrawal of flutamide therapy occurred within the first few days, whereas those after withdrawal of bicalutamide therapy occurred within 4 to 8 weeks. Of 4 patients assessed for objective response 2 had stable disease and 2 had progression. A PSA response was observed in the 2 patients with stable disease but not the 2 with progression. CONCLUSIONS: For patients with stage D2 prostate cancer and disease progression or an increasing PSA concentration, withdrawal of antiandrogen therapy with bicalutamide or flutamide may result in a PSA response. The time to PSA response is longer with bicalutamide than with flutamide. The clinical significance of the antiandrogen withdrawal phenomenon is unknown.

Aged↗