Serologic Response to Human Papillomavirus Genotypes Among Unvaccinated Women: Findings From the HITCH Cohort Study.

BACKGROUND: Humoral immune responses may be critical for preventing, controlling, and/or eliminating human papillomavirus (HPV) infection. We analyzed humoral response to natural HPV infection considering phylogenetic relatedness among unvaccinated women. METHODS: We included 399 young women attending university/college in Montreal, Canada who were participants of the HITCH cohort. Participants provided blood samples at baseline and 5 follow-up visits. Antibody response to bacterially expressed L1 and E6 glutathione S-transferase (GST) fusion proteins, and virus-like particles (VLP-L1) of Alphapapillomavirus types were measured using multiplex serology. We assessed correlations and associations between HPV types at baseline using Pearson correlation coefficients (r) and univariable linear regressions. RESULTS: At baseline, > 40% were seropositive for GST-L1 antibodies of at least 1 HPV type. Strong correlations between GST-L1 were observed for α9 HPV types: 58-52 (r = 0.86), 58-33 (r = 0.75), 33-52 (r = 0.72), and between GST-E6: 52-11 (r = 0.84), 52-18 (r = 0.79), 58-33 (r = 0.78), 35-11 (r = 0.76). HPV16 VLP-L1 moderately explained variability in HPV16 GST-L1 (regression coefficient [b] = 0.38, R2 = 43.1%), and HPV45 GST-L1 in HPV18 GST-L1 (b = 0.68, R2 = 42.8%). GST-E6 antibodies accounted for a low to moderate proportion of variability in HPV16 and HPV18 GST-E6 (R2 = 6.4%-62.2%). CONCLUSIONS: Associations between naturally induced HPV-specific antibodies depend on phylogenetic relatedness.

Chronic prednisone, metformin, and nonsteroidal anti-inflammatory drug use and clinical outcome in a cohort of bladder cancer patients undergoing radical cystectomy in Québec, Canada.

BACKGROUND: Studies have suggested a positive association between bladder cancer (BC) outcome and comedication use, including nonsteroidal anti-inflammatory drugs (NSAID), metformin, and prednisone use. To validate these associations, we evaluated whether these medications were associated with clinical outcome in a Canadian cohort of BC patients. METHODS: This is a retrospective cohort study on BC patients undergoing radical cystectomy (RC) in Québec province in 2000-2015, as registered in the provincial health administration databases. Medication use was considered chronic when prescribed for ≥ 1 year. Overall (OS), disease-specific (DSS) and recurrence-free (RFS) survival were compared using multivariable Cox proportional hazards models. Covariates included age, Charlson's comorbidity index, region of residence, year of RC, distance to hospital, hospital type, hospital and surgeon annual RC volume, neoadjuvant chemotherapy use, and type of bladder diversion, as well as mutual adjustment for concomitant comedication use (statins, NSAIDs, metformin, and prednisone). RESULTS: Of 3742 patients included, 293, 420, and 1503 patients chronically used prednisone, metformin, and NSAIDs before surgery, respectively. In multivariable analyses, preoperative prednisone use was associated with improved OS (HR 0.67, 95%CI 0.55-0.82), DSS (HR 0.58, 95%CI 0.45-0.76), and RFS (HR 0.61, 95%CI 0.47-0.78). Patients who chronically used metformin preoperatively had a worse OS (HR 1.29, 95%CI 1.07-1.55), DSS (HR 1.38, 95%CI 1.10-1.72), and RFS (HR 1.41, 95%CI 1.13-1.74). Preoperative, chronic NSAID use was not significantly associated with all clinical outcomes, with adjusted HRs for OS, DSS, and RFS of 1.10 (95%CI 0.95-1.27), 1.24 (95%CI 1.03-1.48), and 1.22 (95%CI 1.03-1.45), respectively. Directionality of findings was similar when stratifying by comedication use in the year following surgery. Results were similar after propensity-score matching too. CONCLUSIONS: In our Canadian cohort of BC undergoing RC, chronic prednisone use was associated with improved clinical outcomes, while metformin and NSAID were not.

Male Circumcision and Genital Human Papillomavirus (HPV) Infection in Males and Their Female Sexual Partners: Findings From the HPV Infection and Transmission Among Couples Through Heterosexual Activity (HITCH) Cohort Study.

BACKGROUND: Previous studies examining the association between male circumcision (MC) and human papillomavirus (HPV) infections have reported inconsistent results. We used data from the HPV Infection and Transmission Among Couples Through Heterosexual Activity (HITCH) cohort study to examine the association between MC and HPV infections in males and their female sexual partners. METHODS: We enrolled monogamous couples in a longitudinal study between 2005 and 2011 in Montreal, Canada. We used logistic and Poisson regression models with propensity score adjustment to estimate odds ratios (ORs) and rate ratios for the association between MC and the prevalence, transmission, and clearance of HPV infections. RESULTS: Four hundred thirteen couples were included in our study. The prevalence OR for the association between MC and baseline infections was 0.81 (95% confidence interval [CI], .56-1.16) in males and 1.05 (95% CI, .75-1.46) in females. The incidence rate ratio for infection transmission was 0.59 (95% CI, .16-2.20) for male-to-female transmission and 0.77 (95% CI, .37-1.60) for female-to-male transmission. The clearance rate ratio for clearance of infections was 0.81 (95% CI, .52-1.24). CONCLUSIONS: We found little evidence of an association between MC and HPV infection prevalence, transmission, or clearance in males and females. Further longitudinal couple-based studies are required to investigate this association.

Multiple lines of chemotherapy for patients with high-grade ovarian cancer: Predictors for response and effect on survival.

Guidelines for the treatment of tubo-ovarian cancer patients beyond third line are lacking. We aimed to evaluate the effect of response in each line on patient's outcome as well as identify variables that predict response for additional line of chemotherapy. A cohort study was performed including all patients with advanced high-grade ovarian cancer. Survival analysis was performed using Kaplan-Meier curves and log-rank tests. Odds ratios and hazard ratios were calculated using multilevel, mixed-effects logistic regression and Cox regression, adjusting for repeated measures within individual patients. Two-hundred thirty-eight patients were included and underwent up to 10 lines of chemotherapy. The median progression-free survival was 15.6 and overall survival (OS) was 55.6 months. Response rates dropped with each additional line and by line 5, most patients (61%) became refractory and only 16% had any type of response (complete 4% or partial 12%). By line 2, whether a patient had partial disease (PR), stable disease (SD) or progressive disease (PD) did not have an effect on the OS. From line 2, whether a patient had PR, SD or PD did not have an effect on chemotherapy-free interval. Number of previous lines and time from previous line were the only variables that significantly correlated with both outcome of patients and response to the next line. In conclusion, time interval from the previous line of chemotherapy is the major clinical factor that predicts beneficial effect of another line of treatment in patients with ovarian cancer.

Development and evaluation of a new non-competitive Luminex immunoassay detecting antibodies against human papillomavirus types 6, 11, 16 and 18.

Serum antibody levels can be used to measure the humoral immune response against human papillomaviruses (HPV). We developed and validated a rapid, technically simple and relatively inexpensive multiplex non-competitive Luminex-based immunoassay (ncLIA) to measure total IgG antibody levels against four HPV types. For the assay's solid phase, virus-like particles (VLPs) of HPV6, 11, 16 and 18 were bound to heparin-coated beads. HPV serum antibody levels binding to the VLPs were quantified using a phycoerithrin-conjugated secondary polyclonal donkey anti-human IgG antibody. Standardization and validation of the ncLIA were performed using 96 paired serum and genital samples from participants in the HITCH cohort study, including young women (aged 18-24 years) and their male sexual partners (aged 18+) in Montreal, Canada. Results from the ncLIA were compared to a validated Luminex immunoassay from PPD laboratories using Pearson's correlation coefficients, receiver operating characteristic curves and logistic regression. Our assay had good inter- and intra-assay variability. The correlation of serum antibody levels between the ncLIA and validation assay was highest for HPV16 and HPV11 (r=0.90), followed by HPV6 (r=0.86) and HPV18 (r=0.67). The ncLIA was better able to predict HPV DNA positivity in genital samples than the validation assay for HPV16 [area under the curve (AUC) 0.65 versus 0.52, P=0.001] and HPV18 [AUC 0.71 versus 0.57, P=0.024]. AUCs for HPV6 and HPV11 were similar between the two assays (0.70 versus 0.71, P=0.59, and 0.88 versus 0.96, P=0.08, respectively). The developed ncLIA is useful for measuring total IgG antibody response following natural infection or vaccination against four HPV VLPs included in the quadrivalent vaccine.

The added value of sentinel node mapping in endometrial cancer.

OBJECTIVE: To evaluate long-term oncological outcomes and the added value of sentinel lymph node sampling (SLN) compared to pelvic lymph node dissection (LND) in patients with endometrial cancer (EC). METHODS: During the evaluation phase of SLN for EC, we performed LND and SLN and retrospectively compared the oncologic outcome with the immediate non-overlapping historical era during which patients underwent LND. RESULTS: From 2007 to 2010, 193 patients underwent LND and from December 2010 to 2014, 250 patients had SLN mapping with completion LND. Both groups had similar clinical characteristics. During a median follow-up period of 6.9 years, addition of SLN was associated with more favorable oncological outcomes compared to LND with 6-year overall survival (OS) of 90% compared to 81% (p = 0.009), and progression free survival (PFS) of 85% compared to 75% (p = 0.01) respectively. SLN was associated with improved OS (HR 0.5, 95% CI 0.3-0.8, p = 0.004), and PFS (HR 0.6, 95% CI 0.4-0.9, p = 0.03) in a multivariable analysis, adjusted for age, ASA score, stage, grade, non-endometrioid histology, and LVSI. Patients who were staged with SLN were less likely to have a recurrence in the pelvis or lymph node basins compared to patients who underwent LND only (6-year recurrence-free survival 95% vs 90%, p = 0.04). CONCLUSION: Addition of SLN to LND was ultimately associated with improved clinical outcomes compared to LND alone in patients with endometrial cancer undergoing surgical staging, suggesting that the data provided by the analysis of the SLN added relevant clinical information, and improved the decision on adjuvant therapy.

The impact of wait times on oncological outcome in high-risk patients with endometrial cancer.

OBJECTIVE: To evaluate the impact of surgical wait times on outcome of patients with grade 3 endometrial cancer. METHODS: All consecutive patients surgically treated for grade 3 endometrial cancer between 2007 and 2015 were included. Patients were divided into two groups based on the time interval between endometrial biopsy and surgery: wait time from biopsy to surgery ≤12 weeks (84 days) vs more than 12 weeks. Survival analyses were conducted using log-rank tests and Cox proportional hazards models. RESULTS: A total of 136 patients with grade 3 endometrial cancer were followed for a median of 5.6 years. Fifty-one women (37.5%) waited more than 12 weeks for surgery. Prolonged surgical wait times were not associated with advanced stage at surgery, positive lymph nodes, increased lymphovascular space invasion, and tumor size (P = .8, P = 1.0, P = .2, P = .9, respectively). In multivariable analysis adjusted for clinical and pathological factors, wait times did not significantly affect disease-specific survival (adjusted hazard ratio [HR]: 1.2, 95% confidence interval [CI], 0.6-2.5, P = .6), overall survival (HR: 1.1, 95% CI, 0.6-2.1, P = .7), or progression-free survival (HR: 0.9, 95% CI, 0.5-1.7, P = .8). CONCLUSION: Prolonged surgical wait time for poorly differentiated endometrial cancer seemed to have a limited impact on clinical outcomes compared to biological factors.

CA-125 reduction during neoadjuvant chemotherapy is associated with success of cytoreductive surgery and outcome of patients with advanced high-grade ovarian cancer.

INTRODUCTION: The objective was to assess whether an early response to neoadjuvant chemotherapy in women with advanced ovarian cancer may predict short- and long-term clinical outcome. MATERIAL AND METHODS: This is a retrospective study of all women with stage III-IV tubo-ovarian cancer treated with neoadjuvant chemotherapy at a single center in Montreal between 2003 and 2014. Logistic regression models were used to evaluate the association between cancer antigen 125 (CA-125) levels during neoadjuvant chemotherapy and debulking success. Cox proportional hazard models were used to estimate hazard ratios and their respective 95% CI for death and recurrence. Harrell's concordance indices were calculated to evaluate which variables best predicted the chemotherapy-free interval and overall survival in our population. RESULTS: In all, 105 women were included. Following the first, second, and third cycles of neoadjuvant chemotherapy, CA-125 levels had a median reduction of 43.2%, 85.4%, and 92.9%, respectively, compared with CA-125 levels at diagnosis. As early as the second cycle, CA-125 was associated with overall survival (hazard ratio 1.03, 95% CI 1.01-1.05, per 50 U/mL increment). By the third cycle, CA-125 did not only predict overall survival (hazard ratio 1.04, 95% CI 1.01-1.08), but it predicted overall survival better than the success of debulking surgery (Harrell's concordance index 0.646 vs 0.616). Both absolute CA-125 levels and relative reduction in CA-125 levels after 2 and 3 cycles predicted the chance to achieve complete debulking (P < .05). CONCLUSIONS: Reduction of CA-125 levels during neoadjuvant chemotherapy provides an early predictive tool that strongly correlates with successful cytoreductive surgery and long-term clinical outcome in women with advanced high-grade serous and endometrioid ovarian cancer.

Human Papillomavirus Viral Load and Transmission in Young, Recently Formed Heterosexual Couples.

BACKGROUND: We studied the association between human papillomavirus (HPV) viral load (VL) and HPV concordance. METHODS: The HITCH cohort study included young, heterosexual, recently formed, sexually active couples. Questionnaires and genital samples were collected at 0 and 4 months. Samples were tested for HPV DNA by polymerase chain reaction (PCR; Linear Array). VLs of HPV6/11/16/18/31/42/51 were quantified using type-specific real-time PCR. Correlations between VL and type-specific HPV prevalence and incidence were evaluated using multilevel, mixed-effects linear/logistic regression models. RESULTS: We included 492 couples. VLs were higher in penile than vaginal samples. VL at subsequent visits correlated significantly within men (r, 0.373), within women (r, 0.193), and within couples (r range: 0.303-0.328). Men with high VL had more type-specific persistent HPV infections (odds ratio [OR], 4.6 [95% confidence interval {CI}, 2.0-10.5]). High VL in men was associated with prevalent (OR, 5.3 [95% CI, 2.5-11.2]) and incident (OR, 6.7 [95% CI, 1.5-30.7]) type-specific HPV infections in their partner. Women's VL was associated with type-specific HPV prevalence in their partner at the same (OR, 5.9) and subsequent (OR, 4.7) visit. CONCLUSIONS: Persistent HPV infections have limited VL fluctuations. VL between sex partners are correlated and seem predictive of transmission episodes.

Risk factors for lymph nodes involvement in obese women with endometrial carcinomas.

OBJECTIVE: To assess risk factors for lymph node involvement in patients with endometrial cancer and a body-mass index (BMI) ≥30 kg/m2. MATERIALS AND METHODS: A retrospective analysis was performed of obese patients diagnosed with endometrial carcinoma between 2007 and 2015, treated in a single center in Montreal. Preoperative variables evaluated were age, BMI, parity, and preoperative ASA score, grade, CA-125 and histology. Odds ratios (OR) and hazard ratios (HR) and their respective 95% confidence intervals (95%CI) were calculated using multivariable logistic regression and Cox proportional hazard models. RESULTS: The study included 230 women with BMI ≥30, 223 (97.0%) had complete staging. Pelvic lymph node involvement was detected in 26 patients (11.3%). Sentinel node detection and pelvic lymph node dissection decreased with increasing BMI (adjusted OR 0.86, 95%CI 0.76-0.97 and 0.76, 95%CI 0.59-0.96, respectively, per 1 kg/m2 increment). Pelvic lymph node involvement was inversely correlated with BMI (adjusted OR 0.88, 95%CI 0.79-0.99) and present in 16/85 (18.8%), 6/56 (10.7%), and 4/82 (4.9%) of patients with a BMI of 30.0-34.9, 35.0-39.9, and ≥40.0 kg/m2, respectively. Preoperative CA-125 was associated with lymph node involvement (adjusted OR 2.77, 95%CI 1.62-4.73, per quartile increment). CONCLUSION: Pelvic lymph node dissection might be omitted in selected cases of morbidly obese patients with failed sentinel nodes mapping and a low CA-125.

Optimization of the 2014 Gleason grade grouping in a Canadian cohort of patients with localized prostate cancer.

OBJECTIVES: To evaluate the five-tier Gleason grade group (GG) scoring of prostate cancers adopted by the International Society of Urology Pathology (ISUP) in 2014, and to propose modifications to optimize its performance. PATIENTS AND METHODS: Data were obtained from PROCURE, a prospective cohort of patients with localized prostate cancer undergoing radical prostatectomy in Québec, 2006-2013. Surgical specimens were evaluated by genitourinary pathologists using 2014 ISUP criteria. Treatment failure was defined as biochemical recurrence and/or initiation of secondary, non-adjuvant therapy. Analyses were conducted using Kaplan-Meier methods, log-rank tests, Cox proportional hazards models and Harrell's concordance indices. RESULTS: A total of 1 917 patients were included, with a median follow-up of 69 months. The 5-year treatment failure rates were 9.6%, 23.5%, 43.1%, 52.6% and 84.3% in GG1-5, respectively (P < 0.001 when comparing GG2 with GG3). Treatment failure rates for patients in GG2 and GG3 with tertiary Gleason 5 pattern were higher than patients in the same group without a tertiary pattern (P < 0.001), but were similar to rates for patients in GGs 3 or 4 without a tertiary pattern (P > 0.3). Primary Gleason pattern (4/5) predicted treatment failure in GG5 (5-year failure rates 82.3% vs 97.1%, respectively; P = 0.001). The five-tier GG system had greater accuracy as a prognostic indicator compared with the four-tier system (Harrell's concordance index 0.716 vs 0.676). When upgrading patients in GG2/3 with tertiary Gleason 5 pattern to patients in GG3/4, and separating patients in GG5 by primary Gleason pattern, the Harrell's concordance index increased to 0.730. CONCLUSION: The five-tier GG system increased accuracy for predicting treatment failure compared with the previous grading systems, but can be further improved.

The relationship between body-mass index, physical activity, and pathologic and clinical outcomes after radical prostatectomy for prostate cancer.

PURPOSE: We evaluated whether an increased body-mass index (BMI) and decreased physical activity increase the risk of locally advanced or high-risk prostate cancer (PCa) at radical prostatectomy (RP), and treatment failure after surgery. METHODS: Data were collected from the PROCURE Biobank, a prospective cohort of patients with localized PCa undergoing RP in four academic centers in Québec between 2006 and 2013. Treatment failure was defined as biochemical recurrence and/or initiation of secondary, non-adjuvant therapy, and analyzed using the Kaplan-Meier method, log-rank tests, and Cox proportional-hazards models. Uni- and multivariate (ordered) logistic regression was used for time-independent variables. RESULTS: 1813 patients were included. Median follow-up time was 69 months. Patients who reported a lower BMI were generally older, of Asian descent, and physically more active (p < 0.05). Younger, black, and overweight/obese patients reported less physical activity (p < 0.05). In multivariate analyses, a higher BMI increased the risk for locally advanced, high-risk PCa (defined as a pT3, N1 and/or Gleason 8-10 tumor; odds ratio 1.33, p < 0.001), but increased physical activity did not predict high-risk disease (odds ratio 0.84, p = 0.39). Patients with a higher BMI also had a larger prostate at surgery (odds ratio 1.13, p = 0.03). BMI and physical activity were not associated with positive surgical margins or time to treatment failure (p > 0.05). CONCLUSIONS: BMI was an independent predictor for locally advanced, high-risk disease in this cohort of PCa patients undergoing RP, but was unrelated to treatment failure. Physical activity was not related to locally advanced, high-risk PCa or treatment failure.

Psychosocial adjustment to a prostate cancer diagnosis in a cohort of radical prostatectomy patients in Quebec, Canada.

OBJECTIVE: The psychosocial impact of a prostate cancer diagnosis significantly affects a patient's quality of life. We studied patient communication at the time of diagnosis and its impact on psychosocial adjustment of patients. METHODS: This is a cross-sectional data analysis from self-administered questionnaires in the PROCURE biobank study, consisting of a cohort of patients with localized prostate cancer undergoing radical prostatectomy in Québec (Canada), 2006 to 2013. Odds ratios (OR) and their respective 95% confidence intervals (95% CI) were calculated using binary or ordered logistic regression models. RESULTS: Data from 1841 patients were analyzed. The median age of patients was 62 years (range 41-80 years), the majority was French-Canadian (68.3%) and married (79.6%). Most patients (90.1%) considered conversations with their treating physician a useful information source. Patients were dissatisfied on the communication when receiving their diagnosis by telephone (OR = 0.19, 95% CI, 0.11-0.33). Younger patients were also more dissatisfied. Most patients preferred to receive information on prostate cancer (89.5%) and radical prostatectomy (88.0%) at the time of diagnosis, while only 58.8% and 52.4% of patients received this information at this stage. Patients who were dissatisfied with the communication of the diagnosis had more negative responses, such as increased worries and fear (P < 0.05). The five most useful coping mechanisms were physical activity (62.3%), breathing exercises (44.5%), music (32.8%), faith (30.3%), and muscle relaxation (30.1%), but varied by demographics. CONCLUSIONS: This study highlights the importance of physicians communicating a prostate cancer diagnosis well to their patients. Patients may benefit from individually tailored interventions to facilitate their overall coping.

Short- and long-term survival has improved after radical cystectomy for bladder cancer in Québec during the years 2000-2015.

BACKGROUND AND OBJECTIVES: We evaluated the short- and long-term outcome in bladder cancer (BC) patients treated with radical cystectomy (RC) in Québec (Canada). METHODS: Data were collected from provincial registries on all BC patients who underwent RC in Québec province in 2000-2015. Outcomes were hospitalization rates and survival. Survival analyses were conducted using log-rank tests and Cox proportional hazards models. RESULTS: In total, 4450 patients were included in our analysis. RC was increasingly conducted by higher-volume surgeons in larger, higher-volume, academic hospitals. Comparing patients treated in 2010-2015 to 2000-2009, recently treated patients had shorter postoperative hospital stays (absolute difference, 0.9 days, P < 0.001) but also a higher readmission rate (25.0% vs 21.1% in the 30 days following discharge, P = 0.003). Overall (5-year rates 50.9% vs 42.7%, P < 0.001) and BC-specific survival (61.3% vs 55.5%, P < 0.001) had significantly improved. In multivariable analyses, overall survival was significantly better in recently treated patients (hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.60-0.73), younger patients (HR, 1.16; 95% CI, 1.14-1.19), patients residing closer to the hospital (HR, 1.03; 95% CI, 1.01-1.06), and patients treated by high-volume surgeons (HR, 0.88; 95% CI, 0.82-0.94). CONCLUSIONS: Survival in BC patients after RC has improved in recent years. Other predictors for survival are younger age, shorter distance between patients' residences and hospitals, and higher surgeon's RC loads.

Does hormonal therapy for fertility preservation affect the survival of young women with early-stage endometrial cancer?

BACKGROUND: The incidence of endometrial cancer among young women is increasing. Some patients with low-grade endometrial cancer receive hormone therapy (HT) before surgery to preserve fertility. It is unclear whether this adversely affects survival. METHODS: Patients with localized, low-grade endometrial cancer who were aged <45 years were selected from the Surveillance, Epidemiology, and End Results database between 1993 and 2012. Propensity score matching was used to select comparable groups receiving HT or primary surgery. Cancer-specific and overall survival were measured using Kaplan-Meier methods. Hazard ratios and 95% confidence intervals (95% CIs) were estimated using Cox models adjusted for age, period of diagnosis, marital status, race, tumor grade, morphology, and previous radiotherapy. RESULTS: A total of 6339 women were included in the current study cohort, 161 of whom initially received HT and 6178 of whom received primary surgery. After 15 years of follow-up, all-cause mortality did not differ between the groups (HT group: 14.1% [95% CI, 6.7%-28.4%] and propensity score-matched primary surgery group: 9.3% [95% CI, 4.1%-20.5%]). Cancer-specific mortality appeared higher in patients treated with HT compared with those treated with primary surgery (9.2% [95% CI, 3.4%-24.0%] vs 2.1% [95% CI, 1.5%-2.8%]). However, this difference was driven by 3 late deaths in the HT group. Sensitivity analyses using a broader definition of cancer-specific mortality provided no statistical evidence of a survival difference between the treatment groups. The hazard ratio for the overall risk of death was 1.45 (95% CI, 0.44-4.74). CONCLUSIONS: Based on this population-based cohort, young patients with low-grade endometrial cancer appear to have excellent survival, regardless of the primary therapy chosen (HT vs primary surgery). The current selection of patients for HT to preserve fertility, which is managed carefully by experienced clinicians, does not appear to significantly worsen clinical outcomes. Cancer 2017;123:1545-1554. © 2017 American Cancer Society.

CAST: A retrospective analysis of cabazitaxel and abiraterone acetate sequential treatment in patients with metastatic castrate-resistant prostate cancer previously treated with docetaxel.

Cabazitaxel and abiraterone have both received approval for treating metastatic castrate-resistant prostate cancer (mCRPC) patients after first-line docetaxel therapy. In the cabazitaxel and abiraterone sequential treatment (CAST) study, the clinical outcome of docetaxel-treated mCRPC patients treated sequentially with both cabazitaxel and abiraterone was studied. Data were collected retrospectively from mCRPC patients at 12 hospitals across the Netherlands who initiated cabazitaxel and/or abiraterone before December 2012. Primary outcome measure was overall survival (OS); secondary measures were progression-free survival (PFS), biochemical PFS, and best clinical and PSA response. Hospital admission data during treatment were collected, as well as toxicities resulting in treatment discontinuation or patient death. Sixty-three and 69 patients received Cab→Abi (cabazitaxel prior to abiraterone) and Abi→Cab before July 10th, 2013, respectively. Median OS was 19.1 months and 17.0 months in Cab→Abi and Abi→Cab treated patients, respectively (p = 0.369). Median PFS and biochemical PFS were significantly longer in Cab→Abi treated patients: 8.1 versus 6.5 (p = 0.050) and 9.5 versus 7.7 months (p = 0.024), respectively. Although partial responses to cabazitaxel occurred in both groups, Abi→Cab treated patients had a significantly decreased antitumor response from cabazitaxel than Cab→Abi treated patients (median PFS 5.0 versus 2.6 months, p < 0.001). Minor differences in toxicities were observed based on therapy sequence; generally, toxicity from cabazitaxel could be severe, while abiraterone toxicity was milder. This retrospective analysis indicates that primary progression on cabazitaxel or abiraterone did not preclude a response to the other agent in mCRPC patients. However, tumor response of both agents, particularly cabazitaxel, was lower when administered as higher-line therapy in the selected study population.

Chemotherapy- and irradiation-induced bone loss in adults with solid tumors.

It is estimated that bone loss occurs in 70 % of all patients dying from cancer, causing a significant disease burden in cancer patients. Bone loss is caused by cancer itself and its metastases, but also by cancer therapies. Of the cancer therapy-induced bone loss, hormone therapies are best known for their bone damaging abilities. However, chemo- and radiotherapy may result in bone loss too. In this review, direct and indirect effects of various chemotherapies (such as methotrexate, imatinib, and taxanes) that cause bone loss are discussed. Furthermore, we discuss bone loss caused by radiotherapy and radionuclides, of which the latter may be reduced with the introduction of the alpha-emitter Radium-223. Finally, agents preventing chemotherapy- or radiotherapy-induced bone loss, in particular denosumab and bisphosphonates, are being reviewed for their efficacy in preventing chemotherapy- and irradiation-induced bone loss in cancer patients.

Under-representation of racial minorities in prostate cancer studies submitted to the US Food and Drug Administration to support potential marketing approval, 1993-2013.

BACKGROUND: US Food and Drug Administration (FDA) approval of new drugs depends on results from clinical trials that must be generalized to the US population. However, racial minorities are frequently under-represented in clinical studies. The enrollment of racial minorities was compared in key clinical studies submitted to the FDA in the last 10 years in support of potential marketing approval for prostate cancer (PCa) prevention or treatment. METHODS: Patient demographic data were obtained from archival data sets of large registration trials submitted to the FDA to support proposed PCa indications. Six countries/regions were analyzed: the United States, Canada, Australia, Europe, the United Kingdom, and Eastern Europe. Background racial demographics were collected from national census data. RESULTS: Seventeen key PCa clinical trials were analyzed. These trials were conducted in the past 20 years, comprising 39,574 patients with known racial information. Most patients were enrolled in the United States, but there appeared to be a trend toward increased non-US enrollment over time. In all countries, racial minorities were generally under-represented. There was no significant improvement in racial minority enrollment over time. The United States enrolled the largest nonwhite population (7.1%). CONCLUSIONS: Over the past 20 years, racial minorities were consistently under-represented in key PCa trials. There is a need for effective measures that will improve enrollment of racial minorities. With increased global enrollment, drug developers should aim to recruit a patient population that resembles the racial demographics of the patient population to which drug use will be generalized upon approval.

Targeting prostate cancer cell lines with polo-like kinase 1 inhibitors as a single agent and in combination with histone deacetylase inhibitors.

Combinations of anticancer therapies with high efficacy and low toxicities are highly sought after. Therefore, we studied the effect of polo-like kinase 1 (Plk1) inhibitors on prostate cancer cells as a single agent and in combination with histone deacetylase (HDAC) inhibitors valproic acid and vorinostat. IC50s of Plk1 inhibitors BI 2536 and BI 6727 were determined in prostate cancer cells by MTS assays. Morphological and molecular changes were assessed by immunoblotting, immunofluorescence, flow cytometry, real-time RT-PCR, and pulldown assays. Efficacy of combination therapy was assessed by MTS and clonogenic assays. IC50 values in DU145, LNCaP, and PC3 cells were 50, 75, and 175 nM, respectively, for BI 2536 and 2.5, 5, and 600 nM, respectively, for BI 6727. Human prostate fibroblasts and normal prostate epithelial cells were unaffected at these concentrations. While DU145 and LNCaP cells were solely arrested in mitosis on treatment, PC3 cells accumulated in G2 phase and mitosis, suggesting a weak spindle assembly checkpoint. Combining Plk1 inhibitors with HDAC inhibitors had synergistic antitumor effects in vitro. DMSO-treated prostate cancer cells were used as controls to study the effect of Plk1 and HDAC inhibition. Plk1 inhibitors decreased proliferation and clonogenic potential of prostate cancer cells. Hence, Plk1 may serve as an important molecular target for inhibiting prostate cancer. Combining HDAC inhibitors with BI 2536 or BI 6727 may be an effective treatment strategy against prostate cancer.