Publications by authors named "Kevin Zou"

3 Publications

  • Page 1 of 1

Effectiveness of first-line abiraterone versus enzalutamide among patients ≥80 years of age with metastatic castration-resistant prostate cancer: A retrospective propensity score-weighted comparative cohort study.

Eur J Cancer 2021 Jul 12;152:215-222. Epub 2021 Jun 12.

Department of Medicine, Medical Oncology Division, BC Cancer, Vancouver Centre, University of British Columbia, Vancouver, BC, Canada. Electronic address:

Background: Metastatic castration-resistant prostate cancer (mCRPC) disproportionately affects the elderly. There is limited data assessing the efficacy and tolerability of abiraterone acetate (AA) versus enzalutamide in this population.

Objective: To compare the clinical efficacy and tolerability of AA versus enzalutamide in patients ≥ 80 years with mCRPC.

Design, Setting And Participants: A retrospective propensity-weighted comparative cohort study of first-line AA versus enzalutamide among patients with mCRPC aged ≥80 years.

Outcome Measurements And Statistical Analysis: Inverse probability treatment weights based on propensity scores were generated to assess the treatment effect of AA versus enzalutamide on time to PSA progression (TTPP), time to progression (TTP) (first of PSA/radiographic/clinical progression) and overall survival using a weighted Cox proportional hazards model. PSA response rate (PSA RR) was compared between groups using Χ.

Results And Limitations: One hundred fifty-three patients received AA, and 125 received enzalutamide. Enzalutamide was associated with higher PSA RR (61.6% vs 43.8%, P < 0.004), and TTP (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.50-0.88, P = 0.01) but not TTPP (HR 0.73, 95% CI 0.53-1.01, P = 0.06). There were significantly more dose reductions with enzalutamide (22.9% vs 44.8%, P > 0.001) but there was no interaction between median proportion of full dose received and TTPP or TTP for either drug. Rates of treatment discontinuation (for reasons other than progression) were also significantly different between AA and enzalutamide (28.8% vs 40.8%, respectively, P = 0.04). The most common reason for dose reductions and discontinuation of enzalutamide was fatigue (30.4% and 5.6%, respectively).

Conclusions: Despite more dose reductions and a higher treatment discontinuation rate, enzalutamide was associated with a higher PSA RR and longer time to progression, than AA. Given that clinical outcomes were not adversely impacted by decreased treatment exposure, dose modification may be a useful treatment strategy to balance toxicity and tolerance.
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July 2021

Genomic characterization of MICA gene using multiple next generation sequencing platforms: A validation study.

HLA 2020 10 21;96(4):430-444. Epub 2020 Aug 21.

Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.

We have developed a protocol regarding the genomic characterization of the MICA gene by next generation sequencing (NGS). The amplicon includes the full length of the gene and is about 13 kb. A total of 156 samples were included in the study. Ninety-seven of these samples were previously characterized at MICA by legacy methods (Sanger or sequence specific oligonucleotide) and were used to evaluate the accuracy, precision, specificity, and sensitivity of the assay. An additional 59 DNA samples of unknown ethnicity volunteers from the United States were only genotyped by NGS. Samples were chosen to contain a diverse set of alleles. Our NGS approach included a first round of sequencing on the Illumina MiSeq platform and a second round of sequencing on the MinION platform by Oxford Nanopore Technology (ONT), on selected samples for the purpose of either characterizing new alleles or setting phase among multiple polymorphisms to resolve ambiguities or generate complete sequence for alleles that were only partially reported in the IMGT/HLA database. Complete consensus sequences were generated for every allele sequenced with ONT, extending from the 5' untranslated region (UTR) to the 3' UTR of the MICA gene. Thirty-two MICA sequences were submitted to the IMGT/HLA database including either new alleles or filling up the gaps (exonic, intronic and/or UTRs) of already reported alleles. Some of the challenges associated with the characterization of these samples are discussed.
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October 2020

Clinical effectiveness of docetaxel for castration-sensitive prostate cancer in a real-world population-based analysis.

Prostate 2019 02 28;79(3):281-287. Epub 2018 Oct 28.

Division of Medical Oncology, University of British Columbia, BC Cancer, Vancouver, British Columbia.

Background: Adding docetaxel to androgen deprivation therapy (ADT) for the treatment of metastatic castration-sensitive prostate cancer (mCSPC) has known efficacy, with an overall survival benefit in Phase III clinical trials. The effectiveness of docetaxel with ADT in the general patient population remains undefined.

Patients And Methods: We conducted a population-based retrospective review using the British Columbia Provincial Pharmacy Database. To be included, patients had to have castration-sensitive prostate cancer not previously treated (except in the adjuvant setting) and have received at least one cycle of docetaxel, with complete records available for review. Safety and clinical effectiveness were evaluated.

Results: From April 2015 to February 2017, we identified 183 cases; 156 met inclusion criteria. Most patients had high-volume disease (80%). All 6 planned docetaxel cycles were delivered in 126 cases (81%). Dose reductions and delays were required in 39% and 16% of cases. Grade 3-4 adverse events were noted in 40%, with no treatment-related deaths. The rate of febrile neutropenia was 18% and was significantly associated with the presence of high-volume disease (P = 0.038). PSA ≤ 0.2 ng/L was achieved in 27% of patients after 6 months of ADT and maintained in 16% after 12 months. Patients with over 20 bone metastases had worse time to castration resistant prostate cancer (CRPC) and time to treatment for CRPC, and a trend toward worse overall survival. CRPC developed in 41% within 1 year, with a median time to CRPC of 14.4 months. Treatment for CRPC was given in 84 cases, with 90% receiving either abiraterone or enzalutamide in the first-line, with a PSA decline ≥50% occurring in 47%.

Conclusions: The effectiveness of docetaxel with ADT in a general population of patients with mCSPC was associated with poorer outcomes and high rates of toxicity compared to the published studies. Response rates to first-line treatment for mCRPC with abiraterone or enzalutamide appear similar to reported outcomes.
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February 2019