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ItemPopulation-based studies In urologic cancerTa, Anthony Dinh ( 2019)Introduction Long-term data on cancer outcomes are frequently based on large series from single- or multi-institutional databases, and whilst study numbers may be large, the study population and outcomes are often not truly reflective of community practice. Furthermore, very few of these studies, especially in urologic oncology, include patients diagnosed and treated in Australia. Using a population-based cancer registry, we sought to evaluate long-term survival outcomes in men with prostate cancer treated with surgery in Victoria, and identify the clinicopathologic and sociodemographic factors that influenced survival. Furthermore, we sought to evaluate the practice patterns of management of renal cell carcinoma (RCC) in Victoria, and identify potential differences in management between metropolitan and regional areas. Methods All eligible cases were identified from the Victorian Cancer Registry (VCR). There is a statutory requirement that all diagnoses of invasive cancer, excluding non-melanoma skin cancer, be reported to the VCR. The Victorian Radical Prostatectomy Register (VRPR) is a whole of population series of men who underwent radical prostatectomy for the treatment of prostate cancer between 1995 and 2000 in Victoria. Eligible cases were identified from the VCR and relevant clinicopathologic data was obtained via medical record review. Follow-up PSA and death data were obtained via record-linkage to pathology laboratories and the Victorian Registry of Births, Deaths and Marriages. All cases of RCC diagnosed in Victoria between 1 January 2009 and 31 December 2009 and registered with the VCR were identified. Trained data managers extracted relevant data by retrospective review of medical records and pathology reports. Data extracted included: mode of presentation, diagnostic and staging investigations, clinical and pathological disease stage, socioeconomic data, first line treatment, enrolment in clinical trials, and provision of multidisciplinary care. Case residency was categorised as metropolitan or regional/rural based on the Department of Human Services Integrated Cancer Services regions. Results Between 1995-2000, 2154 men underwent radical prostatectomy in Victoria. During a median follow-up of 10.2 years, 74 men died from prostate cancer. In addition to Gleason score and pathological stage, symptomatic presentation was associated with increased prostate cancer-specific mortality (PCSM). After adjusting for stage and PSA, no difference in PCSM was found between men with Gleason = 6 and Gleason 3+4 = 7 (p=0.649). Men with Gleason 4+3 had significantly greater cumulative incidence of PCSM compared to men with Gleason 3+4 (SHR = 2.79, 95% CI 1.40 – 5.54, p = 0.003). 695 men experienced biochemical recurrence during follow-up, of which 82% occurred within 5 years of radical prostatectomy. Men with combined high Gleason sum (>4+3) and extra-prostatic (>pT3a) disease had substantially increased mortality rate with early biochemical recurrence (BCR), while those experiencing BCR after a longer interval had significantly lower mortality. Men with combined low Gleason sum (<3+4) and organ-confined disease (
ItemThe oncological outcomes of dose escalated radiotherapy and its impact on biochemical control and toxicity in men with prostate cancersChao, Michael Wan Tien ( 2019)Introduction: Radiation therapy (RT) for prostate cancer (PC) has steadily evolved over many years, with improvement in biochemical relapse free survival (bRFS). An association between overall survival and doses greater than or equal to 75.6 Gray in men with intermediate and high-risk PC has been reported in population-based studies. Contemporary RT techniques such as image guided radiotherapy, intensity modulated radiotherapy, and stereotactic body radiotherapy, has facilitate further dose escalation. Brachytherapy is an internal form of RT that also developed substantially and can be delivered in combination with external beam radiation therapy (EBRT). However, dose escalation can come with increased gastrointestinal (GI) toxicity and new devices such as rectum spacers have been developed to spare this critical normal structure. Methods: Our large prospective brachytherapy database, that I created, which included patients treated with low dose rate (LDR) and high dose rate (HDR) brachytherapy was interrogated to determine the long-term oncological outcomes. In addition, I was one of the first radiation oncologists in Australia to use a novel polyethylene glycol hydrogel rectal spacer and its iodinated counterpart. We were able to implement its use as a fiducial marker in the post-prostatectomy setting and its use as a tissue expander in the intact prostate for EBRT with or without high dose rate brachytherapy as well as in the post-prostatectomy setting. Results: I found that the use of LDR and HDR brachytherapy with or without EBRT to be safe and efficacious. The bRFS for LDR brachytherapy alone for low to intermediate risk PC was excellent as was its use in combination with EBRT for men with predominantly unfavorable intermediate risk PC. In addition, the use of HDR brachytherapy in combination with EBRT for men with intermediate and high-risk PC also yielded excellent bRFS comparable to any other series reported in the literature. I successfully introduced the use of hydrogel spacers into our practice with marked reduction in rectal volumes irradiated to high radiation doses which allowed appropriate dose escalation of EBRT with or without HDR brachytherapy. This has translated to a marked reduction in late GI toxicity. In addition, we also successfully used hydrogel spacers in the post-prostatectomy setting both as a spacer to allow for ultra-high dose radiation therapy and as a fiducial marker with hydrogel spacer in its iodinated form. Conclusion: Although the use of brachytherapy has declined in the last few years, our results confirm its outstanding efficacy in PC and as such we will continue to advocate for its use. We will continue to support a brachytherapy unit for the treatment of PC. In addition, my work on hydrogel spacers has resulted in its use as standard practice in all PC patients who require EBRT.