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Featured researches published by Jonathan I. Izawa.


Journal of Clinical Oncology | 2002

Salvage Cryotherapy for Recurrent Prostate Cancer After Radiotherapy: Variables Affecting Patient Outcome

Jonathan I. Izawa; Lydia T. Madsen; Shellie M. Scott; Jean Paul Tran; Edward J. Mcguire; Andrew C. von Eschenbach; Louis L. Pisters

PURPOSE To determine the long-term disease-specific survival (DSS) and disease-free survival (DFS) rates after salvage cryotherapy for locally recurrent adenocarcinoma of the prostate and to identify pretreatment factors that have an impact on DSS and DFS. PATIENTS AND METHODS Between July 1992 and January 1995, 131 patients who had received definitive radiation therapy (XRT) underwent salvage cryotherapy for locally recurrent adenocarcinoma of the prostate. Cryotherapy failure was defined as an increasing postcryotherapy prostate-specific antigen (PSA) level of > or = 2 ng/mL above the postcryotherapy nadir, a positive prostate biopsy, or radiographic evidence of metastatic disease. Clinical variables were studied to determine whether there was an association with the DSS and DFS. RESULTS The median follow-up was 4.8 years. The 5-year DSS rates were 87% for patients with a precryotherapy Gleason score < or = 8 and 63% for those with Gleason scores of 9 and 10 (P =.012). The 5-year DFS rates were 57% for patients with a precryotherapy PSA level of < or = 10 ng/mL and 23% for those with a PSA level greater than 10 ng/mL (P =.0004). The 5-year DSS rates for patients with a pre-XRT clinical stage of T1 to T2 and those with a clinical stage of T3 to T4 were 94% and 72%, respectively (P =.0041). The 5-year DFS rates for these groups were 90% and 69%, respectively (P =.0057). CONCLUSION Androgen-independent local recurrences, Gleason score, and pre-XRT clinical stage were important factors that had an impact on DSS and DFS. The subset of patients cured by salvage cryotherapy seems to be small, and patient selection is important.


The Journal of Urology | 2009

Soft Tissue Surgical Margin Status is a Powerful Predictor of Outcomes After Radical Cystectomy: A Multicenter Study of More Than 4,400 Patients

Giacomo Novara; Robert S. Svatek; Pierre I. Karakiewicz; Eila C. Skinner; Vincenzo Ficarra; Yves Fradet; Yair Lotan; Hendrik Isbarn; Umberto Capitanio; Patrick J. Bastian; Wassim Kassouf; Hans Martin Fritsche; Jonathan I. Izawa; Derya Tilki; Colin P. Dinney; Seth P. Lerner; Mark P. Schoenberg; Bjoern G. Volkmer; Arthur I. Sagalowsky; Shahrokh F. Shariat

PURPOSE We evaluated the association of soft tissue surgical margins with characteristics and outcomes of patients treated with radical cystectomy for urothelial carcinoma of the bladder. MATERIALS AND METHODS We retrospectively collected the data of 4,410 patients treated with radical cystectomy and pelvic lymphadenectomy without neoadjuvant chemotherapy at 12 academic centers in the United States, Canada and Europe. A positive soft tissue surgical margin was defined as presence of tumor at inked areas of soft tissue on the radical cystectomy specimen. RESULTS Positive soft tissue surgical margins were identified in 278 patients (6.3%). On univariate analysis positive soft tissue surgical margin was significantly associated with advanced pT stage, higher tumor grade, lymphovascular invasion and lymph node metastasis (p <0.001). Actuarial 5-year recurrence-free and cancer specific survival probabilities were 62.8% +/- 0.8% and 69% +/- 0.8% for patients without soft tissue surgical margins vs 21.6% +/- 3.1% and 26.4% +/- 3.3% for those with positive soft tissue surgical margins (p <0.001). On multivariable analyses adjusting for the effect of standard clinicopathological features and adjuvant chemotherapy positive soft tissue surgical margin was an independent predictor of disease recurrence and cancer specific mortality (HR 1.52 and HR 1.51, p <0.001, respectively). Soft tissue surgical margin retained independent predictive value in subgroups with advanced disease such as pT3Nany, pT4Nany or Npositive. CONCLUSIONS Positive soft tissue surgical margin is a strong predictor of recurrence and eventual death from urothelial carcinoma of the bladder. Soft tissue surgical margin status should always be reported in the pathological reports after radical cystectomy. Due to uniformly poor outcomes patients with positive soft tissue surgical margins should be considered for studies on adjuvant local and/or systemic therapy.


BJUI | 2010

International validation of the prognostic value of lymphovascular invasion in patients treated with radical cystectomy.

Shahrokh F. Shariat; Robert S. Svatek; Derya Tilki; Eila C. Skinner; Pierre I. Karakiewicz; Umberto Capitanio; Patrick J. Bastian; Bjoern G. Volkmer; Wassim Kassouf; Giacomo Novara; Hans Martin Fritsche; Jonathan I. Izawa; Vincenzo Ficarra; Seth P. Lerner; Arthur I. Sagalowsky; Mark P. Schoenberg; Ashish M. Kamat; Colin P. Dinney; Yair Lotan; M. Marberger; Yves Fradet

Study Type – Prognosis (retrospective cohort)
Level of Evidence 2b


BJUI | 2011

Contemporary outcomes of 2287 patients with bladder cancer who were treated with radical cystectomy: a Canadian multicentre experience.

Faysal A. Yafi; Armen Aprikian; Joseph L. Chin; Yves Fradet; Jonathan I. Izawa; Eric Estey; Adrian Fairey; Ricardo Rendon; Ilias Cagiannos; Louis Lacombe; Jean-Baptiste Lattouf; David Bell; Darrel Drachenberg; Wassim Kassouf

Study Type – Therapy (case series)


Clinical Cancer Research | 2010

The Effectiveness of Off-Protocol Adjuvant Chemotherapy for Patients with Urothelial Carcinoma of the Urinary Bladder

Robert S. Svatek; Shahrokh F. Shariat; Robert E. Lasky; Eila C. Skinner; Giacomo Novara; Seth P. Lerner; Yves Fradet; Patrick J. Bastian; Wassim Kassouf; Pierre I. Karakiewicz; Hans Martin Fritsche; Stefan Müller; Jonathan I. Izawa; Vincenzo Ficarra; Arthur I. Sagalowsky; Mark P. Schoenberg; Arlene O. Siefker-Radtke; Randall E. Millikan; Colin P. Dinney

Purpose: The role of adjuvant chemotherapy for patients with high-risk urothelial carcinoma of the bladder (UCB) is not well defined. Here we address the value of adjuvant chemotherapy in patients undergoing radical cystectomy for UCB in an off-protocol routine clinical setting. Experimental Design: We collected and analyzed data from 11 centers contributing retrospective cohorts of patients with UCB treated with radical cystectomy without neoadjuvant chemotherapy. Patients were grouped into quintiles based on their risk of disease progression using estimates from a fitted multivariable Cox proportional hazards model. The association of adjuvant chemotherapy with survival was explored across separate quintiles. Results: The cohort consisted of 3,947 patients, 932 (23.6%) of whom received adjuvant chemotherapy. Adjuvant chemotherapy was independently associated with improved survival (hazard ratio, 0.83; 95% confidence interval, 0.72-0.97%, P = 0.017). However, the effect of adjuvant chemotherapy was significantly modified by the individuals risk of disease progression such that an increasing benefit from adjuvant chemotherapy was seen across higher-risk subgroups (P < 0.001). There was a significant improvement in survival between the treated and nontreated patients in the highest-risk quintile (hazard ratio, 0.75; 95% confidence interval, 0.62-0.90; P = 0.002). This group was characterized by an estimated 32.8% 5-year probability of cancer-specific survival, with 86.6% of patients having both advanced pathologic stage (≥T3) and nodal involvement. Conclusion: Adjuvant chemotherapy is associated with a significant improvement in survival for patients treated in an off-protocol clinical setting. Selective administration in patients at the highest risk for disease progression, such as those with advanced pathologic stage and nodal involvement, may optimize the therapeutic benefit of adjuvant chemotherapy. Clin Cancer Res; 16(17); 4461–7. ©2010 AACR.


The Journal of Urology | 2009

Locally Recurrent Prostate Cancer After Initial Radiation Therapy: A Comparison of Salvage Radical Prostatectomy Versus Cryotherapy

Louis L. Pisters; Dan Leibovici; Michael L. Blute; Horst Zincke; Thomas J. Sebo; Jeffrey M. Slezak; Jonathan I. Izawa; John F. Ward; Shellie M. Scott; Lydia T. Madsen; Philippe E. Spiess; Bradley C. Leibovich

PURPOSE We compared the treatment outcomes of salvage radical prostatectomy and salvage cryotherapy for patients with locally recurrent prostate cancer after initial radiation therapy. MATERIALS AND METHODS We retrospectively reviewed the medical records of patients who underwent salvage radical prostatectomy at the Mayo Clinic between 1990 and 1999, and those who underwent salvage cryotherapy at M. D. Anderson Cancer Center between 1992 and 1995. Eligibility criteria were prostate specific antigen less than 10 ng/ml, post-radiation therapy biopsy showing Gleason score 8 or less and prior radiation therapy alone without pre-salvage or post-salvage hormonal therapy. We assessed the rates of biochemical disease-free survival, disease specific survival and overall survival in each group. Biochemical failure was assessed using the 2 definitions of 1) prostate specific antigen greater than 0.4 ng/ml and 2) 2 increases above the nadir prostate specific antigen. RESULTS Mean followup was 7.8 years for the salvage radical prostatectomy group and 5.5 years for the salvage cryotherapy group. Compared to salvage cryotherapy, salvage radical prostatectomy resulted in superior biochemical disease-free survival by both definitions of biochemical failure (prostate specific antigen greater than 0.4 ng/ml, salvage cryotherapy 21% vs salvage radical prostatectomy 61% at 5 years, p <0.001; 2 increases above nadir with salvage cryotherapy 42% vs salvage radical prostatectomy 66% at 5 years, p = 0.002) and in superior overall survival (at 5 years salvage cryotherapy 85% vs salvage radical prostatectomy 95%, p = 0.001). There was no significant difference in disease specific survival (at 5 years salvage cryotherapy 96% vs salvage radical prostatectomy 98%, p = 0.283). After adjusting for post-radiation therapy biopsy Gleason sum and pre-salvage treatment serum prostate specific antigen on multivariate analysis salvage radical prostatectomy remained superior to salvage cryotherapy for the end points of any increase in prostate specific antigen greater than 0.4 ng/ml (HR 0.24, p <0.0001), 2 increases in prostate specific antigen (HR 0.47, p = 0.02) and overall survival (HR 0.21, p = 0.01). CONCLUSIONS Young, healthy patients with recurrent prostate cancer after radiation therapy should consider salvage radical prostatectomy as it offers superior biochemical disease-free survival and may potentially offer the best chance of cure.


BJUI | 2011

Discrepancy between clinical and pathological stage: External validation of the impact on prognosis in an international radical cystectomy cohort

Robert S. Svatek; Shahrokh F. Shariat; Giacomo Novara; Eila C. Skinner; Yves Fradet; Patrick J. Bastian; Ashish M. Kamat; Wassim Kassouf; Pierre I. Karakiewicz; Hans Martin Fritsche; Jonathan I. Izawa; Derya Tilki; Vincenzo Ficarra; Bjoern G. Volkmer; Hendrik Isbarn; Colin P. Dinney

Study Type – Prognosis (case series) Level of Evidence 4


Archives of Pathology & Laboratory Medicine | 2006

Malignant neoplasm of perivascular epithelioid cells of the liver.

Jeremy R. Parfitt; Anthony J. Bella; Jonathan I. Izawa; Bret Wehrli

Neoplasms of perivascular epithelioid cells (PEComas) have in common the coexpression of muscle and melanocytic immunohistochemical markers. Although this group includes entities with distinct clinical features, such as angiomyolipoma, clear cell sugar tumor of the lung, and lymphangioleiomyomatosis, similar tumors have been documented in an increasing diversity of locations. The term PEComa is now generally used in reference to these lesions that are not angiomyolipomas, clear cell sugar tumors, or lymphangioleiomyomatoses. While most reported PEComas have behaved in a benign fashion, malignant PEComas have occasionally been documented. We present a case of hepatic PEComa with benign histologic features, which nonetheless presented with metastases to multiple sites nearly 9 years later. This case represents the second documented malignant PEComa of the liver, as well as the longest follow-up of a surviving patient with a malignant PEComa, emphasizing both the need for criteria that more accurately predict the behavior of PEComas and the necessity of long-term follow-up of patients with PEComas.


Cancer Research | 2005

A New Three-Dimensional Ultrasound Microimaging Technology for Preclinical Studies Using a Transgenic Prostate Cancer Mouse Model

Lauren A. Wirtzfeld; Guojun Wu; Michael Bygrave; Yasuto Yamasaki; Hideki Sakai; Madeleine Moussa; Jonathan I. Izawa; Donal B. Downey; Norman M. Greenberg; Aaron Fenster; Jim W. Xuan; James C. Lacefield

Prostate cancer is the most common cancer in adult men in North America. Preclinical studies of prostate cancer employ genetically engineered mouse models, because prostate cancer does not occur naturally in rodents. Widespread application of these models has been limited because autopsy was the only reliable method to evaluate treatment efficacy in longitudinal studies. This article reports the first use of three-dimensional ultrasound microimaging for measuring tumor progression in a genetically engineered mouse model, the 94-amino acid prostate secretory protein gene-directed transgenic prostate cancer model. Qualitative comparisons of three-dimensional ultrasound images with serial histology sections of prostate tumors show the ability of ultrasound to accurately depict the size and shape of malignant masses in live mice. Ultrasound imaging identified tumors ranging from 2.4 to 14 mm maximum diameter. The correlation coefficient of tumor diameter measurements done in vivo with three-dimensional ultrasound and at autopsy was 0.998. Prospective tumor detection sensitivity and specificity were both >90% when diagnoses were based on repeated ultrasound examinations done on separate days. Representative exponential growth curves constructed via longitudinal ultrasound imaging indicated volume doubling times of 5 and 13 days for two prostate tumors. Compared with other microimaging and molecular imaging modalities, the application of three-dimensional ultrasound imaging to prostate cancer in mice showed advantages, such as high spatial resolution and contrast in soft tissue, fast and uncomplicated protocols, and portable and economical equipment that will likely enable ultrasound to become a new microimaging modality for mouse preclinical trial studies.


Journal of Clinical Oncology | 2011

Prospective Multi-Institutional Study Evaluating the Performance of Prostate Cancer Risk Calculators

Robert K. Nam; Michael W. Kattan; Joseph L. Chin; John Trachtenberg; Rajiv Singal; Ricardo Rendon; Laurence Klotz; Linda Sugar; Christopher Sherman; Jonathan I. Izawa; David Bell; Aleksandra Stanimirovic; Vasundara Venkateswaran; Eleftherios P. Diamandis; Changhong Yu; D. Andrew Loblaw; Steven A. Narod

PURPOSE Prostate cancer risk calculators incorporate many factors to evaluate an individuals risk for prostate cancer. We validated two common North American-based, prostate cancer risk calculators. PATIENTS AND METHODS We conducted a prospective, multi-institutional study of 2,130 patients who underwent a prostate biopsy for prostate cancer detection from five centers. We evaluated the performance of the Sunnybrook nomogram-based prostate cancer risk calculator (SRC) and the Prostate Cancer Prevention Trial (PCPT) -based risk calculator (PRC) to predict the presence of any cancer and high-grade cancer. We examined discrimination, calibration, and decision curve analysis techniques to evaluate the prediction models. RESULTS Of the 2,130 patients, 867 men (40.7%) were found to have cancer, and 1,263 (59.3%) did not have cancer. Of the patients with cancer, 403 (46.5%) had a Gleason score of 7 or more. The area under the [concentration-time] curve (AUC) for the SRC was 0.67 (95% CI, 0.65 to 0.69); the AUC for the PRC was 0.61 (95% CI, 0.59 to 0.64). The AUC was higher for predicting aggressive disease from the SRC (0.72; 95% CI, 0.70 to 0.75) compared with that from the PRC (0.67; 95% CI, 0.64 to 0.70). Decision curve analyses showed that the SRC performed better than the PRC for risk thresholds of more than 30% for any cancer and more than 15% for aggressive cancer. CONCLUSION The SRC performed better than the PRC, but neither one added clinical benefit for risk thresholds of less than 30%. Further research is needed to improve the AUCs of the risk calculators, particularly for higher-grade cancer.

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Joseph L. Chin

University of Western Ontario

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Colin P. Dinney

University of Texas MD Anderson Cancer Center

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