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U O Nseyo

Publications and source records attributed to U O Nseyo.

At least 19 recordsLinked to original sources
PubMed2006

Hypericum perforatum L. extract - novel photosensitizer against human bladder cancer cells.

The polar methanolic fraction (PMF) of the Hypericum perforatum L. extract has recently been developed and tested as a novel, natural photosensitizer for use in the photodynamic therapy (PDT), and photodynamic diagnosis (PDD). PMF has been tested on HL-60 leukemic cells and cord blood hemopoietic progenitors. In the present study, the efficacy of PMF as a phototoxic agent against urinary bladder carcinoma has been studied using the T24 (high grade metastatic cancer), and RT4 (primary low grade papillary transitional cell carcinoma) human bladder cancer cells. Following cell culture incubation, PMF was excited using 630 nm laser light. The photosensitizer exhibited significant photocytotoxicity in both cell lines at a concentration of 60microg/ml, with 4-8 J/cm(2) light dose, resulting in cell destruction from 80% to 86%. At the concentration of 20microg/ml PMF was not active in either cell line. These results were compared with the results obtained in the same cell lines, under the same conditions with a clinically approved photosensitizer, Photofrin. Photofrin was used in the maximum clinically tolerable dose of 4microg/ml, and it was also excited with 630 nm laser light. In the T24 cell Photofrin exhibited slightly less photocytotocixity, compared with PMF, resulting in 77% cell death with 8J/cm(2) light dose. However, against the RT4 cells Photofrin resulted in minimal cell death (9%) with even 8J/cm(2) light dose. Finally, the type of cell death induced by PMF photoactivation was studied using flow cytometry and DNA laddering. Cell death by PMF photodynamic action in these two bladder cell lines is caused predominently by apoptosis. The reported significant photocytotoxicity, selective localization, natural abundance, easy, and inexpensive preparation, underscore that the PMF extract hold the promise of being a novel, effective PDT photosensitizer.

Apoptosis↗
PubMed2001

CD44 standard form expression as a predictor of progression in high risk superficial bladder tumors.

OBJECTIVE: The purpose of this study was to assess the significance of the standard CD44 adhesion molecule expression in predicting progression of high risk superficial bladder carcinoma in the short term. METHODS: Sixty-six patients (51 males and 15 females, aged 27 to 89 years (mean 64.75 years) with primary superficial transitional cell bladder cancer initially treated with transurethral resection (TURBT) were enrolled in the study. Only pTa/pT1 grade 2 multiple tumors as well as all grade 3 tumors were included in this study. All tumor samples obtained after the resection were immunohistochemically evaluated for the expression of the CD44 standard molecule. Fifty eight patients remained during the follow up period which ranged from 3 to 36 months (mean 11.8 months). Tumor progression in the short term was considered as the critical end point of interest in this study. The prognostic significance of tumor stage, grade, presence of carcinoma-in-situ (CIS) and expression of CD44 in determining the risk for progression, was studied with both univariate (log rank test) and multivariate (Cox proportional hazards) methods of analysis. RESULTS: Kaplan-Meier survival curves indicated that a shorter median progression-free survival is expected for those patients with G3 bladder tumors (p = 0.0055), concomitant CIS (p = 0.0051), and loss of expression of CD44 (p = 0.0015), whereas a similar association with stage was not detected (p = 0.5793). The cox regression multivariate analysis did not yield a significant result for any of the studied parameters therefore no one of the factors taken into account can serve as an independent predictor of progression in superficial bladder cancer in the short term. CONCLUSION: The immunohistochemically detectable loss of the expression of CD44 standard form from superficial bladder tumor samples may be, complementary to the established prognostic factors, a useful predictor of tumor progression in the short term.

Adult↗
PubMed2000

Primary testicular seminoma in a patient with a history of extragonadal non-seminomatous germ cell carcinoma.

Extragonadal germ cell carcinoma represents between 3% and 5% of all germ cell carcinomas. A metachronous primary germ cell carcinoma is exceedingly rare in these patients. We report the eighth case, which occurred in a 29-year-old man who presented with testicular seminoma 7 years after his initial presentation with extragonadal non-seminomatous germ cell carcinoma. The seven other patients also presented with extragonadal non-seminomatous germ cell carcinoma, followed subsequently by testicular seminoma in 6 patients and non-seminomatous germ cell carcinoma in the seventh. The mean time to presentation was 8 years. Although rare, this case emphasizes the need for long-term surveillance, including testicular evaluation of patients with a history of extragonadal germ cell carcinoma.

Adult↗
PubMed1998

Superficial bladder cancer: the role of interferon-alpha.

PURPOSE: We evaluate the clinical experience with recombinant interferon-alpha in superficial transitional cell carcinoma and discuss the most rational use of recombinant interferon-alpha in the context of current treatment options. MATERIALS AND METHODS: The available data were reviewed and discussed at a consensus conference in August 1996. The conclusions and recommendations are those of the authors based on the consensus reached at that meeting. RESULTS: While bacillus Calmette-Guerin (BCG) is recognized as the most efficacious intravesical agent in the prophylaxis and treatment of superficial transitional cell carcinoma, it is associated with significant toxicities and a 20 to 40% relapse rate. Interferons, particularly recombinant interferon-alpha, have demonstrated efficacy against primary and recurrent papillary transitional cell carcinoma and carcinoma in situ with minimal toxicity, although the response and relapse rates are inferior to BCG. Intravesical recombinant interferon-alpha therapy has also produced responses in patients who failed to respond or were refractory to BCG or chemotherapy. CONCLUSIONS: The clinical experience suggests that recombinant interferon-alpha has an important role in the treatment of superficial transitional cell carcinoma, particularly as second line therapy following failure of BCG or chemotherapy, and it may have synergistic effects when combined with chemotherapy or BCG. We propose a prospective randomized study comparing the efficacy of recombinant interferon-alpha, BCG and BCG plus recombinant interferon-alpha as maintenance following complete response to primary BCG therapy. The proposed study would also investigate the efficacy of BCG plus recombinant interferon-alpha as second line therapy following BCG failure. This study will be important to determine the most effective strategy to integrate recombinant interferon-alpha into current treatment options for superficial bladder cancer.

Administration, Intravesical↗
PubMed1998

Photodynamic therapy (PDT) in the treatment of patients with resistant superficial bladder cancer: a long-term experience.

INTRODUCTION AND OBJECTIVE: Photodynamic therapy (PDT) combines a photosensitizer such as Photofrin with red laser light (630 nm) to destroy cancer cells. Investigators have reported effectiveness of PDT in the management of patients with recurrent superficial bladder cancer. We retrospectively reviewed our experience in 58 patients to assess the long-term role of PDT in the management of resistant superficial transitional cell carcinoma (TCC) including Ta, T1, and refractory carcinoma in situ (CIS) of the urinary bladder. MATERIALS AND METHODS: All 58 patients had failed at least one course of standard intravesical therapy or had contraindication for intravesical chemo- or immunotherapy. Patients with malignancy present (Ta-T1/Grade I-III, CIS) were accepted for ablative PDT. Patients undergoing prophylactic PDT after complete resection were confirmed to be tumor-free by cystoscopy and bladder was cytology before PDT. Post-PDT evaluations included weekly telephone contact to assess acute adverse reactions and assessment of efficacy and bladder toxicity at three months and quarterly thereafter. RESULTS: These 58 patients underwent a single PDT treatment with 2.0 or 1.5 mg/kg of Photofrin and 10-60 J/cm2 light (630 nm). At three months, complete response rates were 84% and 75% for residual resistant papillary TCC and refractory CIS respectively; and 90% of patients treated prophylactically had not had recurrences. At a median followup of 50 months (range 9-110), 59% (34/58) of the responders are alive, with 31/34 still disease-free. CONCLUSION: PDT using 1.5 mg/kg of Photofrin and 15 J/cm2 of light (630 nm) should be considered a safe and effective treatment for refractory CIS or recurrent papillary TCC.

Adult↗
PubMed1998

Photodynamic therapy using porfimer sodium as an alternative to cystectomy in patients with refractory transitional cell carcinoma in situ of the bladder. Bladder Photofrin Study Group.

PURPOSE: Photodynamic therapy combines a photosensitizer, such as porfimer sodium (Photofrin), with red laser light (630 nm.) to destroy cancer cells. Investigators have reported the effectiveness of photodynamic therapy in the treatment of patients with recurrent superficial bladder cancer. We assess the safety and efficacy of 1 or 2 photodynamic treatments using porfimer sodium and controlled uniform laser light (630 nm.) as an alternative to cystectomy in patients with refractory vesical carcinoma in situ of the bladder. MATERIALS AND METHODS: A total of 36 patients with carcinoma in situ were treated with whole bladder photodynamic therapy as an alternative to cystectomy. In all patients at least 1 course of bacillus Calmette-Guerin (BCG) had failed. Each patient received a single whole bladder photodynamic therapy treatment, consisting of 2 mg./kg. porfimer sodium intravenously followed 40 to 50 hours later by intravesical red light (630 nm.) at 15 J./cm.2. Post-photodynamic therapy evaluations included weekly telephone contact to assess acute adverse reactions, and assessment of efficacy and bladder toxicity at 3 months and quarterly thereafter. RESULTS: At initial clinical evaluation at 3 months 58% of the patients had a complete response as indicated by negative cystoscopy, bladder biopsy and urine cytology but in 42% treatment failed. At a mean followup of 12 months (range 9 to 48) 10 of the 21 complete responders had recurrence for an overall durable response rate of 31%. Fourteen patients subsequently underwent cystectomy for persistent carcinoma in situ (12) and carcinoma in situ recurrence (2). Of the 36 patients 7 experienced bladder contracture. CONCLUSIONS: The initial results are encouraging for a single whole bladder photodynamic treatment of patients in whom prior intravesical therapy for carcinoma in situ has failed. While followup is short, porfimer sodium photodynamic therapy appears potentially promising as an alternative to cystectomy in patients with refractory carcinoma in situ.

Adult↗
PubMed1997

Treatment of renal cell carcinoma with 5-fluorouracil and alfa-interferon.

OBJECTIVES: Renal cell carcinoma is relatively resistant to both chemotherapy and immunotherapy. Response, survival, duration of response, and toxicity of treatment were evaluated in patients with advanced renal cell carcinoma receiving a continuous intravenous infusion of 5-fluorouracil (5-FU) and low dose subcutaneous alfa-2b-interferon. METHODS: Between 1989 and 1994, 21 patients with advanced renal cell carcinoma underwent treatment with continuous intravenous infusion of 5-FU, 200 mg/m2/day, and subcutaneous injections of recombinant interferon alfa-2b (IFN-alpha), 1 x 10(6) U/day. RESULTS: Objective response was observed in 9 patients (43%). Complete response occurred in 4 patients (19%): 2 with lung, 1 with bone, and 1 with liver metastasis. Partial response occurred in 5 patients (24%). Three of 4 complete responders remain alive without recurrence. Mean survival rate was 195 weeks among complete responders, 184 weeks among partial responders, and 88 weeks among nonresponders. The overall mean duration of response was 101 weeks. Responders developed progression of disease a mean of 62 weeks after the initial response to therapy. Mild dose-dependent toxicity was related to 5-FU infusion. Nearly all toxicities subsided with the temporary cessation of 5-FU infusion and/or decreasing the dose of the infusion. Few if any of the toxicities appear to be directly related to the low dose interferon injections. CONCLUSIONS: Although this study is based on a small sample size, we believe that the encouraging complete and partial responses, apparent prolongation of survival, and manageable toxicity of this combination therapy warrant further investigation with larger randomized trials.

Adult↗
PubMed1996

Photodynamic therapy in the management of bladder cancer.

Photodynamic therapy (PDT) is primarily suggested for the therapy of papillary transitional cell carcinoma (TCC) and refractory carcinoma in situ (CIS), and prophylaxis of recurrent superficial TCC in those patients who have failed intravesical chemotherapy or immunotherapy. We reviewed our 13-year experience to assess the long-term role of PDT in the management of superficial bladder cancer, and propose a standard protocol. Fifty eight patients underwent a single PDT treatment with 1.5-2.0 mg/kg of Photofrin and 10-25 J/cm2 of light (630 nm). This single PDT treatment produced overall response rates of 84.2% in 19 patients with recurrent superficial papillary TCC, 80% in 20 patients with refractory CIS, and 89.5% in 19 patients receiving prophylaxis. The PDT dose of 2.0 mg/kg and 15-25 J/cm2 produced the most durable tumor response at the expense of severe local morbidity. However, the PDT dose of 1.5 mg/kg and 10-15 J/cm2 yielded variable tumor responses, with minimal local morbidity. Overall our data confirm that PDT is an effective therapy for superficial bladder cancer. We recommend PDT as a second line or immediate therapy for BCG or chemotherapy failures using a standard PDT dose of 1.5 mg/kg of Photofrin and 15 J/cm2 (630 nm) and a scheduled repeat treatment with 1.5 mg/kg and 10 J/cm2 at 6 and 12 months.

Adult↗
PubMed1996

Therapy of superficial bladder cancer.

Intravesical therapy has been used in the management of superficial transitional cell carcinoma (TCC) of the urinary bladder (Ie, Ta, Tl, and carcinoma in situ [CIS]) with specific objectives that include treating existing/residual tumor, preventing recurrence of tumor, preventing disease progression, and prolonging survival. The initial clinical stage and grade remain the main determinant factors in survival irrespective of the treatment. Intravesical chemotherapy has shown a decrease in short-term tumor recurrence rates, but has had no positive impact on disease progression or prolongation of survival. Presently, bacillus Calmette-Guèrin vaccine (BCG) immunotherapy remains the most effective treatment and prophylaxis for TCC (Ta, Tl, CIS) and has positive outcome on tumor recurrence rate, disease progression, and prolongation of survival. Prostatic urethral mucosal involvement with bladder cancer can also be effectively treated with BCG intravesical immunotherapy. Interferons, keyhole limpet hemocyanin and photofrin-photodynamic therapy are under investigation in the management of TCC and early results are encouraging. This review highlights and summarizes the recent advances in intravesical therapy and prophylaxis of superficial TCC.

BCG Vaccine↗
PubMed1995

Apparent failure of current intravesical chemotherapy prophylaxis to influence the long-term course of superficial transitional cell carcinoma of the bladder.

During the 4 decades since the first introduction of intravesical chemotherapy, 3,899 patients were enrolled in 22 randomized prospective controlled studies. Of these 22 studies 13 reported a statistically significant benefit of intravesical chemotherapy. With varying followup, the reported decrease in the incidence of patients with tumor recurrence averaged only 14% (range -3 to +43%). Unfortunately, long-term (5-year) studies show no decrease in the incidence of recurrent tumor. Maintenance chemotherapy has failed to improve these results and data suggest that a single early postoperative instillation may, in fact, be most effective. Among 10 studies that include progression data none showed decreased tumor progression, and overall among 2,011 randomized patients progression occurred in 7.5% of those receiving intravesical chemotherapy and 6.9% of those treated by surgery alone. Since intravesical chemotherapy has been demonstrated in animal models to be carcinogenic, these data raise the concern that intravesical chemotherapy might possibly be carcinogenic in humans. In the absence of demonstrated long-term benefit we question the advisability of routine prophylactic intravesical chemotherapy.

Administration, Intravesical↗
PubMed1994

Predicting the risk of lymph node involvement using the pre-treatment prostate specific antigen and Gleason score in men with clinically localized prostate cancer.

PURPOSE: To evaluate the predictive value of an empirically derived equation for identifying patients with clinically localized prostate cancer at low and high risk for harboring occult lymph node metastasis. METHODS AND MATERIALS: A simple equation for estimating the risk of positive lymph nodes was empirically derived from a nomogram published by Partin et al. demonstrating the value of combining the pre-treatment prostate specific antigen and Gleason Score in predicting the risk of lymph node metastasis for patients with clinically localized prostate cancer. The risk of positive nodes (N+) was calculated using the equation; N+ = 2/3(PSA) + (GS-6) x 10, where PSA and GS are the pre-treatment prostate specific antigen and Gleason Score respectively, and the calculated risk is constrained between 0-65% for a PSA < or = 40 ng/ml (as in the nomogram). To test the general applicability of this equation, we reviewed the pathologic features of 282 of our patients who had undergone a radical prostatectomy. RESULTS: Based on 212 patients for whom the pre-operative prostate specific antigen's and Gleason Scores were available, we identified 145 patients with a calculated risk of positive nodes of < 15%, (low risk group) and 67 patients with a calculated risk as > or = 15% (high risk group). The observed incidence of positive nodes was 6% and 40% among the low and high risk groups respectively (p < 0.001). When used alone neither clinical stage, pre-treatment prostate specific antigen nor the pre-treatment Gleason Score was as useful in identifying the largest low and high risk groups. CONCLUSION: Using the equation described we confirmed the general applicability of the nomogram reported by Partin et al. and identified patients at low and high risk for lymph node involvement. Based on these data we have adopted a policy of omitting whole pelvic irradiation in patients identified as low risk.

Biomarkers, Tumor↗
PubMed1993

Fluorescence detection of tumors. Early diagnosis of microscopic lesions in preclinical studies.

BACKGROUND: The growth of microscopic tumor lesions at or beyond treatment field margins poses a major problem in the diagnosis and treatment of cancer. Early detection techniques that clearly define the location or field spread of disease may improve the planning of disease treatment. METHODS: In vivo fluorescence photometry is a non-imaging technique that digitally displays relative fluorescence values in volts proportional to the luminescence intensity detected by a silicon photodiode. The sensitivity of the instrument has allowed the detection of micrometastases in preclinical studies. RESULTS: Statistical analysis demonstrates that the photosensitizer Photofrin (dihematoporphyrin ether and/or ester) (Quadra Logic Technologies, QLT, Vancouver, B.C., Canada), currently used for photodynamic therapy, administered in doses lower than those used in clinical studies, is useful for the detection of occult disease. With the drug doses used, cutaneous photosensitivity was avoided in the animal models tested. The results in Lobund-Wistar rats with transplantable prostatic adenocarcinoma (PA-III) demonstrated the utility of this technique in detecting clinically occult disease, with a prediction rate of approximately 94% with drug doses as low as 0.25-0.5 mg/kg. CONCLUSIONS: With the use of the hamster buccal cavity model involving the initiation and promotion of premalignant and malignant conditions by 9,10 dimethyl-1,2-benzanthracene, the technique could discern these two stages of disease with significance levels that were less than 0.05 and 0.01, respectively.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1993

Canine bladder response to red and green light whole bladder photodynamic therapy.

A normal canine bladder model was used to compare the effects of red and green light whole bladder photodynamic therapy (PDT). Eighteen dogs were treated with Photofrin 1 mg/kg and whole bladder irradiation with red or green light at doses ranging from 20 to 60 J/cm2. Toxicity was assessed using cystometry, cystoscopy, and histopathology. Green light produced more significant vesical toxicity than red light, and this toxicity tended to vary with the light dose administered. Whole bladder PDT with green light at doses greater than 20 J/cm2 resulted in permanent reductions in bladder capacity. Conversely, a green light dose of 20 J/cm2 and red light doses ranging from 20 to 60 J/cm2 did not produce any significant permanent reductions in bladder capacity. Thus, while green light may be more toxic to the bladder than red light, there are distinct combinations of red or green light and Photofrin which can be used in the canine bladder to achieve mucosal degradation without causing permanent vesical dysfunction.

Animals↗
PubMed1993

Green light photodynamic therapy in the human bladder.

We conducted this pilot clinical study to investigate the safety, primarily acute toxicity, of green light (514.5 nm) whole bladder photodynamic therapy (PDT) in human bladders with transitional cell carcinoma. We enrolled five patients who were scheduled to undergo radical cystectomy and urinary diversion for locally muscle invasive bladder cancer. Four patients received intravenous injection of Photofrin at 1 mg/kg, while one patient received no drug, 48 hr before undergoing green light whole bladder photoactivation with light doses of 20-60 J/cm 2. Each patient underwent radical cystectomy on day 7 following light treatment. Post-PDT evaluation included daily monitoring of voiding symptoms, cystometric measurements of bladder capacity, and gross and histopathologic examination of the excised bladders. Our results show that the intensity of acute bladder irritation and acute post-PDT loss in bladder volume depended on the light dose and extent of bladder tumor with the associated inflammation. There was no transmural bladder injury and no treatment related morbidity. These data on acute toxicity suggest that green light whole bladder PDT treatment with 1 mg/kg of Photofrin and 20-40 J/cm 2 of laser power is safe.

Aged↗
PubMed1992

Photodynamic therapy.

The preliminary data suggest that red-light whole-bladder photodynamic therapy is safe and effective in the treatment of Tis and may be useful in the prophylactic management of superficial bladder cancer. Theoretically, whole-bladder photodynamic therapy has the advantage of higher efficacy after a single treatment than most conventional modalities for superficial bladder cancer. In patients with Tis, the complete response rate is 88%, and 25% have recurrences during a mean follow-up of 20 months (range 12-60). In patients undergoing prophylaxis, the recurrence rate is 31% and the median time to recurrence is 18 months. Importantly, none of the high-risk patients treated with whole-bladder photodynamic therapy has developed disease progression in stage or grade at the time of recurrences. Whole-bladder therapy also has the potential advantage of repeat treatment without increased tumor resistance or increased morbidity. Data from the present phase II-III clinical trials involving a large number of patients will define the role of photodynamic therapy in the management of superficial bladder cancer.

Carcinoma in Situ↗