An optimized model for network intrusion detection systems in industry 4.0 using XAI based Bi-LSTM framework

Industry 4.0 enable novel business cases, such as client-specific production, real-time monitoring of process condition and progress, independent decision making and remote maintenance, to name a few. However, they are more susceptible to a broad range of cyber threats because of limited resources and heterogeneous nature. Such risks cause financial and reputational damages for businesses, well as the theft of sensitive information. The higher level of diversity in industrial network prevents the attackers from such attacks. Therefore, to efficiently detect the intrusions, a novel intrusion detection system known as Bidirectional Long Short-Term Memory based Explainable Artificial Intelligence framework (BiLSTM-XAI) is developed. Initially, the preprocessing task using data cleaning and normalization is performed to enhance the data quality for detecting network intrusions. Subsequently, the significant features are selected from the databases using the Krill herd optimization (KHO) algorithm. The proposed BiLSTM-XAI approach provides better security and privacy inside the industry networking system by detecting intrusions very precisely. In this, we utilized SHAP and LIME explainable AI algorithms to improve interpretation of prediction results. The experimental setup is made by MATLAB 2016 software using Honeypot and NSL-KDD datasets as input. The analysis result reveals that the proposed method achieves superior performance in detecting intrusions with a classification accuracy of 98.2%.

Cabazitaxel versus abiraterone or enzalutamide in poor prognosis metastatic castration-resistant prostate cancer: a multicentre, randomised, open-label, phase II trial

BACKGROUND

Treatment of poor prognosis metastatic castration-resistant prostate cancer (mCRPC) includes taxane chemotherapy and androgen receptor pathway inhibitors (ARPI). We sought to determine optimal treatment in this setting.

PATIENTS AND METHODS

This multicentre, randomised, open-label, phase II trial recruited patients with ARPI-naive mCRPC and poor prognosis features (presence of liver metastases, progression to mCRPC after <12 months of androgen deprivation therapy, or ≥4 of 6 clinical criteria). Patients were randomly assigned 1 : 1 to receive cabazitaxel plus prednisone (group A) or physician's choice of enzalutamide or abiraterone plus prednisone (group B) at standard doses. Patients could cross over at progression. The primary endpoint was clinical benefit rate for first-line treatment (defined as prostate-specific antigen response ≥50%, radiographic response, or stable disease ≥12 weeks).

RESULTS

Ninety-five patients were accrued (median follow-up 21.9 months). First-line clinical benefit rate was greater in group A versus group B (80% versus 62%, P = 0.039). Overall survival was not different between groups A and B (median 37.0 versus 15.5 months, hazard ratio (HR) = 0.58, P = 0.073) nor was time to progression (median 5.3 versus 2.8 months, HR = 0.87, P = 0.52). The most common first-line treatment-related grade ≥3 adverse events were neutropenia (cabazitaxel 32% versus ARPI 0%), diarrhoea (9% versus 0%), infection (9% versus 0%), and fatigue (7% versus 5%). Baseline circulating tumour DNA (ctDNA) fraction above the cohort median and on-treatment ctDNA increase were associated with shorter time to progression (HR = 2.38, P < 0.001; HR = 4.03, P < 0.001). Patients with >30% ctDNA fraction at baseline had markedly shorter overall survival than those with undetectable ctDNA (HR = 38.22, P < 0.001).

CONCLUSIONS

Cabazitaxel was associated with a higher clinical benefit rate in patients with ARPI-naive poor prognosis mCRPC. ctDNA abundance was prognostic independent of clinical features, and holds promise as a stratification biomarker.

Adverse event profile for immunotherapy agents compared with chemotherapy in solid organ tumors: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Immunotherapy agents are an innovative oncological treatment modality and as a result their use has expanded widely. Understanding the treatment-related adverse events (AEs) of these drugs compared with traditional chemotherapy is crucial for clinical practice.

DESIGN

A systematic review of studies indexed in Medline (PubMed), Embase, Web of Science, and the Cochrane Databases from January 2000 to 14 February 2019 was conducted. Randomized clinical trials comparing immunotherapy [cytotoxic T-lymphocyte protein-4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed death-ligand 1 (PD-L1)] with standard-of-care chemotherapy in the treatment of advanced solid-organ neoplasms were included if AEs were reported as an outcome. Primary outcome was AEs ≥ grade 3 in severity. Secondary outcomes were proportion of overall AEs, treatment discontinuation due to AEs, deaths due to AEs, and specific AEs [fatigue, diarrhea, acute kidney injury (AKI), colitis, pneumonitis, and hypothyroidism]. Paule-Mandel pooling and a random effects model were used to produce odds ratios (ORs) for measures of effects.

RESULTS

Among 10 598 abstracts screened, we included 22 studies involving 12 727 patients. In the immunotherapy group, 16.5% of patients developed an AE ≥ grade 3 in severity, compared with 41.09% in the chemotherapy arm [OR = 0.26, 95% confidence interval (CI) 0.19-0.35, I² = 92%]. Patients receiving immunotherapy also had lower odds of developing an AE overall (OR = 0.35, 95% CI 0.28-0.44; I² = 77%), terminating therapy due to an AE (OR = 0.55, 95% CI 0.39-0.78, I² = 80%), or dying from a treatment-related AE (OR = 0.67, 95% CI 0.46-0.98, I² = 0%). When treated with chemotherapy versus immunotherapy, patients more frequently experienced fatigue (25.10% versus 15.83%), diarrhea (14.97% versus 11.13%), and AKI (1.79% versus 1.31%). However, colitis (1.02% versus 0.26%), pneumonitis (3.36% versus 0.36%), and hypothyroidism (6.82% versus 0.37%) were more common in those treated with immunotherapy.

CONCLUSIONS

Treatment of advanced solid-organ malignancies with immunotherapy compared with traditional chemotherapy is associated with a lower risk of AEs.

Nomogram Predicting Bladder Cancer-specific Mortality After Neoadjuvant Chemotherapy and Radical Cystectomy for Muscle-invasive Bladder Cancer: Results of an International Consortium

BACKGROUND

Cisplatin-based neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (MIBC) is associated with improved overall and cancer-specific survival. The post-NAC pathological stage has previously been reported to be a major determinant of outcome.

OBJECTIVE

To develop a postoperative nomogram for survival based on pathological and clinical parameters from an international consortium.

DESIGN, SETTING, AND PARTICIPANTS

Between 2000 and 2015, 1866 patients with MIBC were treated at 19 institutions in the USA, Canada, and Europe. Analysis was limited to 640 patients with adequate follow-up who had received three or more cycles of NAC.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A nomogram for bladder cancer-specific mortality (BCSM) was developed by multivariable Cox regression analysis. Decision curve analysis was used to assess the model's clinical utility.

RESULTS AND LIMITATIONS

A total of 640 patients were identified. Downstaging to non-MIBC (ypT1, ypTa, and ypTis) occurred in 271 patients (42 %), and 113 (17 %) achieved a complete response (ypT0N0). The 5-yr BCSM was 47.2 % (95 % confidence interval [CI]: 41.2-52.6 %). On multivariable analysis, covariates with a statistically significant association with BCSM were lymph node metastasis (hazard ratio [HR] 1.90 [95% CI: 1.4-2.6]; p < 0.001), positive surgical margins (HR 2.01 [95 % CI: 1.3-2.9]; p < 0.001), and pathological stage (with ypT0/Tis/Ta/T1 as reference: ypT2 [HR 2.77 {95 % CI: 1.7-4.6}; p < 0.001] and ypT3-4 [HR 5.9 {95 % CI: 3.8-9.3}; p < 0.001]). The area under the curve of the model predicting 5-yr BCSM after cross validation with 300 bootstraps was 75.4 % (95 % CI: 68.1-82.6 %). Decision curve analyses showed a modest net benefit for the use of the BCSM nomogram in the current cohort compared with the use of American Joint Committee on Cancer staging alone. Limitations include the retrospective study design and the lack of central pathology.

CONCLUSIONS

We have developed and internally validated a nomogram predicting BCSM after NAC and radical cystectomy for MIBC. The nomogram will be useful for patient counseling and in the identification of patients at high risk for BCSM suitable for enrollment in clinical trials of adjuvant therapy.

PATIENT SUMMARY

In this report, we looked at the outcomes of patients with muscle-invasive bladder cancer in a large multi-institutional population. We found that we can accurately predict death after radical surgical treatment in patients treated with chemotherapy before surgery. We conclude that the pathological report provides key factors for determining survival probability.

A network approach to developing immuno-oncology combinations in Canada

Immune checkpoint inhibitors have revolutionized care for many cancer indications, with considerable effort now being focused on increasing the rate, depth, and duration of patient response. One strategy is to combine immune strategies (for example, ctla-4 and PD-1/L1-directed agents) to harness additive or synergistic efficacy while minimizing toxicity. Despite encouraging results with such combinations in multiple tumour types, numerous clinical challenges remain, including a lack of biomarkers that reliably predict outcome, the emergence of therapeutic resistance, and optimal management of immune-related toxicities. Furthermore, the selection of ideal combinations from the myriad of immune, systemic, and locoregional therapies has yet to be determined. A longitudinal network-based approach could offer advantages in addressing those critical questions, including long-term follow-up of patients beyond individual trials. The molecular cancer registry Personalize My Treatment, managed by the Networks of Centres of Excellence nonprofit organization Exactis Innovation, is uniquely positioned to accelerate Canadian immuno-oncology (io) research efforts throughout its national network of cancer sites. To gain deeper insight into how a pan-Canadian network could advance research in io combinations, Exactis invited preeminent clinical and scientific advisors from across Canada to a roundtable event in November 2017. The present white paper captures the expert advice provided: leverage longitudinal patient data collection; facilitate network collaboration and assay harmonization; synergize with existing initiatives, networks, and biobanks; and develop an io combination trial based on Canadian discoveries.

Borealis-1: a randomized, first-line, placebo-controlled, phase II study evaluating apatorsen and chemotherapy for patients with advanced urothelial cancer

Background

Five-year survival of patients with inoperable, advanced urothelial carcinoma treated with the first-line chemotherapy is 5%-15%. We assessed whether the Hsp27 inhibitor apatorsen combined with gemcitabine plus cisplatin (GC) could improve overall survival (OS) in these patients.

Patients and methods

This placebo-controlled, double-blind, phase II trial randomized 183 untreated urothelial carcinoma patients (North America and Europe) to receive GC plus either placebo (N = 62), 600 mg apatorsen (N = 60), or 1000 mg apatorsen (N = 61). In the experimental arm, treatment included loading doses of apatorsen followed by up to six cycles of apatorsen plus GC. Patients receiving at least four cycles could continue apatorsen monotherapy as maintenance until progression or unacceptable toxicity. The primary end point was OS.

Results

OS was not significantly improved in the single or combined 600- or 1000-mg apatorsen arms versus placebo [hazard ratio (HR), 0.86 and 0.90, respectively]. Exploratory study of specific statistical modeling showed a trend for improved survival in patients with baseline poor prognostic features treated with 600 mg apatorsen compared with placebo (HR = 0.72). Landmark analysis of serum Hsp27 (sHsp27) levels showed a trend toward survival benefit for poor-prognosis patients in 600- and 1000-mg apatorsen arms who achieved lower area under the curve sHsp27 levels, compared with the placebo arm (HR = 0.45 and 0.62, respectively). Higher baseline circulating tumor cells (≥5 cells/7.5 ml) was observed in patients with poor prognosis in correlation with poor survival. Treatment-emergent adverse events were manageable and more common in both apatorsen-treatment arms.

Conclusions

Even though apatorsen combined with standard chemotherapy did not demonstrate a survival benefit in the overall study population, patients with poor prognostic features might benefit from this combination. Serum Hsp27 levels may act as a biomarker to predict treatment outcome. Further exploration of apatorsen in poor-risk patients is warranted.

A phase II study of the HDAC inhibitor SB939 in patients with castration resistant prostate cancer: NCIC clinical trials group study IND195

BACKGROUND

SB939 is a potent oral inhibitor of class 1, 2, and 4 histone deacetylases (HDACs). These three HDAC classes are highly expressed in castration resistant prostate cancer (CRPC) and associated with poor clinical outcomes. We designed a phase II study of SB939 in men with metastatic CRPC.

METHODS

Patients received SB939 60 mg on alternate days three times per week for 3 weeks on a 4-week cycle. Primary endpoints were PSA response rate (RR) and progression-free survival (PFS). Secondary endpoints included objective response rate and duration; overall survival; circulating tumor cell (CTC) enumeration and safety. Exploratory correlative studies of the TMPRSS2-ERG fusion and PTEN biomarkers were also performed.

RESULTS

Thirty-two patients were enrolled of whom 88 % had received no prior chemotherapy. The median number of SB939 cycles administered was three (range 1-8). Adverse events were generally grade 1-2, with five pts experiencing one or more grade three event. One patient died due to myocardial infarction. A confirmed PSA response was noted in two pts (6 %), lasting 3.0 and 21.6 months. In patients with measurable disease there were no objective responses. Six patients had stable disease lasting 1.7 to 8.0 months. CTC response (from ≥5 at baseline to <5 at 6 or 12 weeks) occurred in 9/14 evaluable patients (64 %).

CONCLUSION

Although SB939 was tolerable at the dose/schedule given, and showed declines in CTC in the majority of evaluable patients, it did not show sufficient activity based on PSA RR to warrant further study as a single agent in unselected patients with CRPC.

Clinical variables associated with PSA response to abiraterone acetate in patients with metastatic castration-resistant prostate cancer

BACKGROUND

Abiraterone acetate (abiraterone) prolongs overall survival (OS) in patients with metastatic castration-resistant prostate cancer (mCRPC). This study's objective was to retrospectively identify factors associated with prostate-specific antigen (PSA) response to abiraterone and validate them in an independent cohort. We hypothesized that the neutrophil/lymphocyte ratio (NLR), thought to be an indirect manifestation of tumor-promoting inflammation, may be associated with response to abiraterone.

PATIENTS AND METHODS

All patients receiving abiraterone at the Princess Margaret (PM) Cancer Centre up to March 2013 were reviewed. The primary end point was confirmed PSA response defined as PSA decline ≥50% below baseline maintained for ≥3 weeks. Potential factors associated with PSA response were analyzed using univariate and multivariable analyses to generate a score, which was then evaluated in an independent cohort from Royal Marsden (RM) NHS foundation.

RESULTS

A confirmed PSA response was observed in 44 out of 108 assessable patients (41%, 95% confidence interval 31%-50%). In univariate analysis, lower pre-abiraterone baseline levels of lactate dehydrogenase, an NLR ≤ 5 and restricted metastatic spread to either bone or lymph nodes were each associated with PSA response. In multivariable analysis, only low NLR and restricted metastatic spread remained statistically significant. A score derived as the sum of these two categorical variables was associated with response to abiraterone (P = 0.007). Logistic regression analysis on an independent validation cohort of 245 patients verified that this score was associated with response to abiraterone (P = 0.003). It was also associated with OS in an exploratory analysis.

CONCLUSIONS

A composite score of baseline NLR and extent of metastatic spread is associated with PSA response to abiraterone and OS. Our data may help understand the role of systemic inflammation in mCRPC and warrant further research.

Abstract P6-07-06: Primary prophylaxis of febrile neutropenia during adjuvant docetaxel and cyclophosphamide (TC) chemotherapy for breast cancer

Background: The combination of docetaxel and cyclophosphamide (TC) for adjuvant treatment of early stage breast cancer improves overall survival compared with doxorubicin and cyclophosphamide (AC) (Jones et al., 2006). Although cardiotoxicity is avoided with TC, the risk of febrile neutropenia (FN) is higher. For TC, reported rates of FN without prophylactic granulocyte colony-stimulating factor (G-CSF) range from 5% in the phase III trial to as high as 46% in retrospective chart reviews. G-CSF is not covered by our provincial cancer funding agency for primary prophylaxis of FN with TC chemotherapy, however it is often prescribed for patients with private insurance. Our aims were twofold: i) to determine the incidence of FN with TC chemotherapy with and without prophylactic G-CSF or antibiotics in two Ontario comprehensive cancer centres, and ii) to evaluate the cost-effectiveness of primary prophylaxis with G-CSF vs. antibiotics.

Methods: Patients who received adjuvant TC chemotherapy between January 1, 2008 and December 31, 2012 were identified through pharmacy databases. Electronic charts were retrospectively reviewed to extract patient characteristics, treatment details including G-CSF and antibiotic use, as well as incidence of FN and duration of hospitalization. A Markov model comparing primary G-CSF prophylaxis, primary antibiotic prophylaxis and secondary G-CSF prophylaxis was constructed to compare the cost-effectiveness of these strategies over a four cycle time horizon. Costs were based on resource utilization from this retrospective cohort and supplemented by the published literature, adjusted to 2012 Canadian dollars. The model took the perspective of the third party payer. Both one-way and probabilistic sensitivity analyses were performed.

Results: 340 patients were treated with TC over the study period. Of the 73 (21%) who did not receive any primary prophylaxis with G-CSF or antibiotics, 23 (32%) developed FN requiring hospitalization and treatment with intravenous antibiotics. However, only 2 of the 192 patients (1%; P &lt;0.0001) who received primary G-CSF prophylaxis (funded by the patient or a third party payer), and 6 of the 53 patients (11%; P &lt;0.01) who received primary antibiotic prophylaxis (97% receiving ciprofloxacin) developed FN. Age ≥65 was a significant risk factor for FN in the absence of G-CSF (56% vs. 25%, P = 0.02). The results of the cost-effectiveness analysis will be presented at the meeting.

Conclusions: The FN rate associated with TC chemotherapy without primary prophylaxis exceeds 30% but may be reduced with prophylactic antibiotics or G-CSF. Unless prophylactic antibiotics are substantially more cost-effective than prophylactic G-CSF for TC chemotherapy in a particular region or country, primary prophylactic G-CSF should be funded, given its greater effectiveness than antibiotics and the global need to minimize the emergence of antibiotic resistance.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-07-06.

Abstract P1-13-14: Discordance of ER and PR status between primary and recurrent breast cancer in association with endocrine therapy

Background: Discordance in tumor receptor status between primary and recurrent tumors has been previously reported. Discordant ER/PR status has been used to differentiate recurrences from new primaries. We evaluated discordance rates of ER and PR expression between the primary and locoregional/contralateral recurrences and examined the relationship with adjuvant endocrine therapy (ET).

Methods: We conducted a retrospective chart review of breast cancer patients (pts) treated with lumpectomy and adjuvant locoregional radiation (RT) from 1999-2005 at the Princess Margaret Cancer Centre. Tumor recurrence was classified as locoregional recurrence (LRR) for ipsilateral breast or lymph node recurrence, contralateral disease (CD) or distant recurrence. ER and PR were assessed by immunohistochemistry; positive if &gt;10% tumor cells staining, borderline if 10% staining, and negative if &lt;10% staining. Univariate analyses were applied to determine the association of receptor discordance with age, menopausal status, tumor grade, endocrine therapy or adjuvant chemotherapy.

Results: All 441 pts had a lumpectomy with negative margins and RT, and had a median follow-up of 8.3 years. The median age at primary surgery was 57, and 67% of pts were postmenopausal. ET (tamoxifen and/or aromatase inhibitors) was initiated in 294 (84%) eligible patients. There were 24 (5.4%) pts with LRR, 20 (4.5%) pts with CD, and 28 (6.3%) with distant metastases. Nine pts with LRR also had distant disease, and 3 pts with CD also had distant disease. Among pts with LRR, 17 had ER/PR status available for comparison. Discordance rates for ER and PR were (1/17) 5.9% and (3/17) 17.6%, respectively, and the most common change was ER becoming positive, and PR becoming negative (75%). For pts with CD, 18 had ER/PR status available for comparison. Discordance rates for ER and PR were (7/18) 38.9% and (9/18) 50%, respectively. The most common change was ER becoming positive (86%), and PR becoming positive (75%). Distant disease receptor status was only available for two patients, therefore not included. The patient with LRR and discordant ER did not receive ET, while pts with LRR and discordant PR all received ET. Among patients with CD, 15% of patients with discordant ER status received ET, and 33% with discordant PR received ET. There was no statistically significant association between discordance rates in either LRR or CD groups and use of ET. Similarly, discordance rates were not associated with the other patient or tumor variables studied, or the development of distant metastases or death.

Conclusions: Discordance of ER and PR expression was low in LRR and higher in CD, where the majority of changes were from negative to positive receptor status. Receptor discordance was not associated with endocrine therapy. This study suggests that the biology of LRR and CD may be different, and re-evaluation of receptor status could lead to additional treatment options becoming available from an endocrine standpoint.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-13-14.

Translating clinical trials to clinical practice: outcomes of men with metastatic castration resistant prostate cancer treated with docetaxel and prednisone in and out of clinical trials

BACKGROUND

Multiple factors can influence outcomes of patients receiving identical interventions in clinical trials and in routine practice. Here, we compare outcomes of men with metastatic castrate-resistant prostate cancer (mCRPC) treated with docetaxel and prednisone in routine practice and in clinical trials.

PATIENTS AND METHODS

We reviewed patients with mCRPC treated with docetaxel at Princess Margaret Cancer Centre. Primary outcomes were overall survival and PSA response rate. Secondary outcomes were reasons for discontinuation and febrile neutropenia. Outcomes were compared for men treated in routine practice and in clinical trials, and with data from the TAX 327 study.

RESULTS

From 2001 to 2011, 438 men were treated, of whom 357 received 3-weekly docetaxel as first-line chemotherapy: 314 in routine practice and 43 in clinical trials. Trial patients were younger and had better performance status. Median survival was 13.6 months [95% confidence interval (95% CI) 12.1-15.1 months] in routine practice and 20.4 months (95% CI 17.4-23.4 months, P = 0.007) within clinical trials, compared with 19.3 months (95% CI 17.6-21.3 months, P < 0.001) in the TAX 327 study. PSA response rates were 45%, 54%, and 53%, respectively (P = NS). Reasons for treatment discontinuation were similar although trial patients received more cycles (median: 6 versus 8 versus 9.5, P < 0.001). Rates of febrile neutropenia were 9.6, 0, and 3% (P < 0.001) while rates of death within 30 days of last dose were 4%, 0%, and 3%, respectively (P = NS).

CONCLUSIONS

Survival of patients with mCRPC treated with docetaxel in routine practice is shorter than for men included in trials and is associated with more toxicity.

A phase 2 study of patupilone in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel: Canadian Urologic Oncology Group study P07a

BACKGROUND

The purpose of this study was to determine the clinical activity of patupilone in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel.

PATIENTS AND METHODS

Eligible patients had progressive disease within 6 months of receiving docetaxel. Patupilone was administered 10 mg/m2 i.v. every 3 weeks. The primary end point was the proportion of patients with a confirmed≥50% prostate-specific antigen (PSA) decline.

RESULTS

Eighty-three patients were enrolled. At baseline, the median time to progression after prior docetaxel was 1.4 months (range 0-5.7). Gastrointestinal serious adverse events occurred in four of the six initial patients leading to a reduction of the starting dose of patupilone to 8 mg/m2 for subsequent patients. Grade 3-4 toxicity at this dose included diarrhea (22%), fatigue (21%), and anorexia (10%). One patient experienced grade 3-4 hematologic toxicity. A PSA decline of ≥50% occurred in 47% of patients. A partial measurable disease response occurred in 24% of assessable patients. A patient-reported pain response was observed in 59% of assessable patients. Median time to PSA progression was 6.1 months [95% confidence interval (CI) 4.7-8.0] and median overall survival was 11.3 months (95% CI 9.8-15.4).

CONCLUSIONS

Patupilone at 8 mg/m2 was tolerable, had antitumor activity, and was associated with symptomatic improvement in patients previously treated with docetaxel.

A review of the patterns of docetaxel use for hormone-resistant prostate cancer at the Princess Margaret Hospital

BACKGROUND

Based on the TAX 327 phase III trial, docetaxel-based chemotherapy is the standard first-line treatment for hormone-resistant prostate cancer (HRPC); however, there is some heterogeneity in the use of this agent in routine clinical practice. The aim of the present study was to examine the patterns of docetaxel use in routine clinical practice at our institution and to compare them with docetaxel use in the TAX 327 clinical trial.

METHODS

We conducted a retrospective chart review of HRPC patients treated with first-line docetaxel between 2005 and 2007 at the Princess Margaret Hospital.

RESULTS

In the first-line setting, 88 patients with HRPC received docetaxel. The main reasons for initiating docetaxel were rising prostate-specific antigen (PSA, 98%) and progressive symptoms (77%). The PSA response rate was 67%; median time to response was 1.5 months, and duration of response was 6.8 months. Median survival was 15.9 months (95% confidence interval: 12.4 to 20.5 months). Patients received a median of 7 cycles of treatment, and the main toxicities were fatigue (35%) and neuropathy (24%). Post docetaxel, 36 patients received second-line treatment with a 22% response rate.

CONCLUSIONS

In routine clinical practice, HRPC patients received docetaxel mainly because of symptomatic disease progression. Overall response rates and toxicities were comparable to those in the TAX 327 trial. However, our patients received a median of only 7 cycles of treatment versus the 9.5 administered on trial, and survival was slightly shorter in our single-institution study. A larger prospective multicentre analysis, including performance status and quality-of-life parameters, may be warranted to determine if docetaxel performs as well in routine clinical practice as it does in the clinical trial setting.

Phase II study of maintenance therapy with temsirolimus (TEM) after response to first-line docetaxel (TAX) chemotherapy in castration-resistant prostate cancer (CRPC)

160

Background: TAX is the standard first-line chemotherapy for CRPC. However, a number of questions remain regarding the optimal use of TAX following maximal response. Aside from intermittent TAX, maintenance therapy with well-tolerated agents such as the mTOR inhibitor TEM could be one strategy to prolong treatment response and the chemotherapy-free interval, without significantly compromising quality of life. In fact, the mTOR pathway is involved in many aspects of CRPC, and mTOR inhibitors have demonstrated significant anti-CRPC activity in preclinical testing.

Methods: CRPC pts eligible for this single-arm, multicenter phase II trial must have received between 6 to 8 cycles of first-line TAX (75 mg/m2 q3wks) with documented treatment response by PSA (>50% decline from baseline) or RECIST criteria. 30 pts will be enrolled and administered weekly TEM (25 mg iv × 4/cycle). The primary endpoint is time to treatment failure (TTF, by RECIST or symptomatic progression). Secondary endpoints include safety (NCI-CTCAE v3.0), quality of life (FACT-P, PPI), changes in PSA doubling time and time to PSA progression, objective tumor response rate (RECIST), and overall survival. We will also study correlative endpoints using plasma and peripheral blood mononuclear cells (i.e., markers of mTOR inhibition, of antiangiogenic TEM effects and of intratumoral hypoxia/acidosis, the latter as potential predictive markers).

Results: 10 pts have been enrolled to date: mean age 68 (range 52-80), prior definitive local therapy (7)—radiation (6), prostatectomy (1), mean PSA at entry 99.28 (2.3- 380.7), ECOG 0 (4) or 1 (6), prior cycles of TAX 6 (6) or 8 (4), sites of metastasis—bone (8), lymph nodes (4), visceral (3). 6 pts have been discontinued due to treatment failure after a mean of 5.3±1.9 cycles (range 3-8) - RECIST (1), symptomatic (2), combined (3). 4 pts are on cycle 1-2-8-9, respectively. TEM has been generally well tolerated without unexpected side-effects, but may have contributed to worsening lymphedema in 1 pt.

Conclusions: TEM maintenance therapy in CRPC pts that have responded to first-line TAX is well tolerated and appears to result in meaningful TTF.

No significant financial relationships to disclose.

The neoadjuvant management of bladder cancer in Canada: A survey of genitourinary medical oncologists

285

Background: The uptake of neoadjuvant chemotherapy (NC) for the treatment of stage II/III bladder cancer remains variable despite evidence supporting its use. The aim of this study is to better understand the use of NC in Canada to facilitate standardization of practice and develop a platform for clinical trials.

Methods: The survey was initially tested on a subset of medical oncologists. It was then e-mailed to 30 medical oncologists across Canada who primarily treat bladder cancer.

Results: In total, 25 (83%) surveys were completed. Respondents were 92% academic based, 100% full time, and 52% in practice for >10 years. The majority of referrals for all stages came from urologists with 4 respondents (16%) seeing 5-10 cases/yr, 10 (40%) seeing 11-15/yr, 5 (20%) seeing 16- 20/yr and 6 (24%) seeing >20/yr. Of these 8 reported having only 1-2 referrals for NC; 7 had 3-4 NC referrals; 7 had 5-6 NC referrals; and 2 reported seeing >6 referrals/year. Patients referred for NC tended to be younger (50-65); Performance Status (PS) 0/1; T-stage T3a/T3b; or nodal status N1/N2. 96% indicated they do offer NC to selected patients as both standard of care and to downsize tumors. Key factors cited for not offering NC were: Age >85, PS 3/4; T-stage T2a or T4a; Nodal status: N3; GFR <40ml/min. Main baseline staging modalities included CT chest/abdomen/pelvis, bone scan and cystoscopy. Gemcitabine/cisplatin was most commonly used with 20% using high-dose MVAC. Six (27%) reported doing midway staging with CT abdomen/pelvis and cystoscopy; 36% report staging after completion of chemo. Average time from last chemotherapy to cystectomy was 4-6 wks, with no patients being offered adjuvant chemotherapy postoperatively.

Conclusions: The majority of GU MO in Canada would offer NC. Stage, PS, renal function, and comorbidities were the biggest determinants of offering NC, while age played a lesser role. The number of overall referrals for NC, however, remains relatively low. We plan to survey urologists in Canada to determine if differences in attitudes about NC or barriers to referrals account for the low number of referrals.

No significant financial relationships to disclose.

Use of serum and tissue biomarker analysis embedded in a phase II clinical trial of cytarabine in castration-refractory prostate cancer to investigate prostate cancer biology

59

Background: Other than the androgen receptor, the TMPRSS2-ERG genomic aberrations in prostate cancer provide the first recent opportunity to target therapy in castration refractory prostate cancer (CRPC). We initiated a phase II clinical trial of cytarabine in docetaxel refractory CRPC on the basis of microarray, in vitro and case report evidence that cytarabine may be particularly effective in men harbouring abnormalities of the ERG oncogenes. Embedded in this clinical trial was the first use of blood mRNA levels of prostate cancer related genes as biomarkers of response and prognosis.

Methods: Patients with docetaxel refractory progressive CRPC received intravenous cytarabine at doses between 1g/m2-0.25 g/m2 q3 weekly. Responses were defined according to PCWG2C. 10 patients were enrolled between June 2007 and January 2010. TMPRSS2:ERG, PSA and PCA3 mRNA copies in whole blood collected with PAXgene tubes at the beginning of each cycle and at trial termination were quantified using transcription-mediated amplification assays. The prototype TMPRSS2:ERG assay detects the gene fusion isoform TMPRSS2 exon1 to ERG exon4.

Results: No patients demonstrated a serum PSA response (PCWG2C). The average number of cycles administered was 2.6. Significant toxicities including grade 3-4 thrombocytopenia (2) and grade 3-4 neutropenia (3). These toxicities necessitated several dose reductions in the protocol, however most patients were removed from trial for serum PSA progression alone. PCA3 and PSA mRNAs were detectable in 8/10 and 9/10 cases, respectively; there was no correlation between serum PSA and PCA3 or PSA mRNA copy levels in blood. Testing for TMPRSS2:ERG in blood was able to predict the presence or absence of the TMPRSS2-ERG rearrangement in 9/10 cases when compared to 3 colour FISH carried out on baseline biopsies/ prostatectomies (2/10 positive for Exon 4:Exon 1 deletion).

Conclusions: Cytarabine administation is ineffective in docetaxel refractory CRPC. Blood mRNA levels of prostate cancer genes reveal novel aspects of prostate cancer biology and have implications for the understanding of circulating tumour cells.

[Table: see text]

Results of a phase II study of single-agent nab-paclitaxel in platinum-refractory second-line metastatic urothelial carcinoma (UC)

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Background: There is currently no standard second-line chemotherapy for platinum- refractory UC. Both paclitaxel and docetaxel are commonly used but response rates are < 20% and no survival advantage has been shown. In this multi-institutional phase II study, we evaluated the efficacy and tolerability of a new albumin-bound nanoparticle formulation of paclitaxel, known as Abraxane (ABI-007) as a single agent in patients with platinum-refractory metastatic UC.

Methods: Patients with measurable UC, progressing on or after first-line platinum-based chemotherapy were enrolled onto this two-stage trial. ABI-007 was given at 260 mg/m2 IV q3weekly until progression. Clinical evaluation, CBC and blood chemistries were performed every cycle with restaging CT scans every 2 cycles.

Results: Accrual is now complete with 48 patients enrolled. Baseline characteristics: Male: Female 40:8; median age 68; ECOG Performance Status 0:1:2, 15:24:8. 248 cycles were delivered: median 5.5 cycles/pt with 17/48 pts (35%) requiring dose reductions. Most frequent adverse events (AE) were alopecia (12%), fatigue (12%), pain (12%), neuropathy (9%) and nausea (4%). The most frequent grade 3+ AE were pain (45%), hypertension (14%), fatigue (8%), joint stiffness (5%), neuropathy (4%) and weakness (4%). Forty patients are evaluable for response: 1 (2.5%) complete response (CR), 11 (28%) partial responses (PR), 9 (23%) stable disease (SD) and 20 (49%) progressive disease. One patient was inevaluable for response, 7 patients are too early for evaluation.

Conclusions: Single-agent ABI-007 was well tolerated with a response rate (CR+PR) of 33% (12/36) and a clinical benefit rate (CR+PR+SD) of 58% (21/36), representing one of the highest reported response rates to date in the second-line UC setting. These results suggest further study of ABI-007 in urothelial carcinoma is warranted.

No significant financial relationships to disclose.

A phase II study of patupilone in patients (pts) with metastatic castration- resistant prostate cancer (CRPC) who have progressed after docetaxel

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Background: Chemotherapy for pts with CRPC who have progressed after docetaxel remains to be defined. Patupilone is an epothilone with broad spectrum pre-clinical activity including in taxane resistant models. Methods: Multicenter, 2-stage design. Pts with metastatic CRPC with progressive disease during or within 6 months of receiving docetaxel were eligible. Patupilone was initially given 10mg/m 2 IV every 3 weeks. PSA response rate (≥50% decline) was the primary endpoint (H0 = 15%, H1 = 25%, α = 0.1, β = 0.2). Secondary endpoints were measurable disease response, serial pain and analgesics scores, progression free survival (PFS) and overall survival (OS). Results: 83 pts were enrolled from March 2007-June 2008. 401 cycles administered (median 5, range 1–15). Baseline characteristics (range): median age 67 (47–85), PSA 212 (2.6–11520), hemoglobin 118 (89–160), median time to progression after docetaxel 1.0 months (0.0–6.0), number of prior chemotherapy regimens 1:2:3+ in 45:28:10 pts, ECOG PS 0–1:2 in 73:10 pts, disease in bone/lymph nodes/viscera in 76/47/14 pts respectively. In the first 6 pts, gastrointestinal serious adverse events (AE) occurred in 4 pts (diarrhea and vomiting) which lead to a dose reduction of patupilone to 8 mg/m2 for subsequent patients. Grade 3/4 related adverse events at this dose included fatigue (16%), diarrhea (13%) and anorexia (5%). There were no grade 3/4 hematologic AEs. In 78 pts evaluable for PSA response, PSA declines of ≥30% and ≥50% have occurred in 44/78 (56%) and 35/78 (45%) with a confirmed PSA response in 25 pts (32%). Partial response occurred in 5% and stable disease in 64% of 44 evaluable pts. Pain response (2 point decline on 6 point scale) occurred in 36 (51%) of 71 pts eligible for analysis. Median PFS for PSA and non-PSA outcomes (measurable disease/symptomatic progression or death) was 7.6 months (3.7–11.5) and 5.6 months (3.9–7.3) respectively. Follow up for OS is continuing. Conclusions: Patupilone 8 mg/m2 every 3 weeks was well tolerated and associated with encouraging PFS, PSA and pain responses in pts with docetaxel resistant/refractory disease. Further investigation of patupilone in this population is warranted.

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Impact of age at diagnosis on survival of hormone-refractory prostate cancer (HRPC) patients

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Background: Conflicting data exist for age as a determinant of overall survival (OS) in pts with HRPC. We hypothesize that young (<55) HRPC pts represent a more aggressive biological phenotype and therefore have a decreased OS. Methods: A retrospective chart review was conducted on 334 consective HRPC pts treated between 1995–2005. Summary statistics for demographic and clinical factors were generated, and Kaplan-Meier (KM) OS curves were created. Bivariate Cox Proportional-Hazards regression was used to test the association of age at diagnosis while adjusting for a covariate, with significant covariates entered into multivariate models. Results: Overall median survivals in the age stratified categories (<55, ≥55–65, ≥65–75, ≥75) were 5.5, 6.9, 7.9, and 4.3 yrs, with 5 yr survivals 51.9%, 67.4%, 67.0%, and 34.9%, respectively. KM curves showed divergence with an overall significant log-rank test (p < 0.0001). Compared to pts ≥65–75, the hazard ratios (HR) for HRPC pts <55 and ≥75 were 1.40 (95% CI 0.90–2.60) and 2.52 (95% CI 1.67–3.82), respectively. However, following multivariate analysis HRs for HRPC pts <55 and ≥75 were 1.60 (95% CI 0.98–2.62) and 1.25 (95% CI 0.71–2.20). Pts <55 and ≥75 presented with advanced stage at diagnosis and progressed to bone metastasis earlier. Pts ≥75 had decreased performance status, more comorbidities, higher PSA at diagnosis, shorter duration of hormone sensitive disease, and were less likely to receive chemotherapy than pts <75. The percentage of rapid PSA doubling times was highest in the <55 cohort. In multivariate analysis with age as a categorical variate, ECOG 3–4 (HR 2.65), time from diagnosis to both HRPC (HR 0.78) and bone metastasis (HR 0.80), and duration of response to androgen ablation (HR 0.86) remained highly predictive. Conclusions: Age at diagnosis influences OS in HRPC with a bimodal survival curve. Pts <55 and ≥75 present with more aggressive disease, translating into reduced median and 5 yr survivals. Other covariates, especially ECOG status, likely account for the decreased OS in the ≥75 cohort. Conversely, pts <55 had an adjusted HR of 1.60 (p = 0.06). Our study supports a growing body evidence that suggests a poor prognosis in younger men; correlating these differences at the molecular level could lead to better targeted therapies.

No significant financial relationships to disclose.

A phase II study of single agent abraxane as second-line therapy in patients with advanced urothelial carcinoma

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Background: Metastatic urothelial cancer progressing on or after first-line platinum-based chemotherapy is incurable and has a very poor prognosis. There is no standard second-line therapy, but the taxanes including paclitaxel, have previously shown activity. Abraxane (ABI-007) is a novel well tolerated albumin-bound nanoparticle formulation of paclitaxel. The goal of this study was to determine the efficacy and tolerability of single agent Abraxane in the second-line metastatic urothelial cancer setting. Methods: Patients with measureable metastatic urothelial cancer, who progressed on or after first-line cisplatin based chemotherapy were enrolled onto this phase II, two-stage multicenter trial. Patients received Abraxane 260 mg/m2 intravenously every 3 weeks. Clinical evaluation, CBC and blood chemistries were performed every cycle and restaging CT scans every 2 cycles. Results: Fourteen patients have been enrolled to date. Patient demographics: M: F 12:2; mean age 64 (range 45–80); ECOG 0:1:2 4:5:5. A total of 57 cycles, avg 4 cycles/ patient (range 1–9) have been administered. There were three dose delays due to neuropathy, pain, and low neutrophil count respectively. There were two dose reductions due to fatigue and neuropathy. Most frequent adverse events (AE) were fatigue, alopecia, anorexia, cough and joint pain; the most frequent grade 3+ AE were fatigue, joint pain, hypertension, joint stiffness and back pain. Fourteen patients are currently evaluable for best response using RECIST criteria. There have been 5 partial responses (PR), 5 stable disease (SD) and 4 progressive disease (PD). Conclusions: Single agent Abraxane was well tolerated in the 2nd line, cisplatin refractory/resistant metastatic urothelial cancer setting. Preliminary efficacy results are encouraging with a clinical benefit rate of 71% (10 out of 14 evaluable pts having either SD or PR). Stage 1 response criteria have been met and accrual is ongoing to a total of 48 patients.

No significant financial relationships to disclose.

A review of the patterns of docetaxel use for hormone refractory prostate cancer (HRPC) at the Princess Margaret Hospital

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Background: Docetaxel is standard of care for the treatment of HRPC, based on two large randomized clinical trials. The aim of this study was to determine if docetaxel use and effectiveness in routine clinical practice was similar to that seen in the TAX 327 randomized phase III clinical trial. Methods: A retrospective chart review was undertaken to assess patterns of docetaxel use for HRPC at our institution for the 2-year period since its approval for the first-line treatment of HRPC in 2005. Results: Eighty-eight patients, median age 71 and baseline PSA 107, received docetaxel in the first line setting. Main reasons for initiating docetaxel were rising PSA (90%) and progressive symptoms (71%). Eighteen percent of patients received docetaxel for rising PSA alone. A median of 7 cycles was administered. PSA response rates were 61%, time to response 1.5 months, and response duration 6.8 months. Disease progression was the most common reason for treatment discontinuation (36%). Main toxicities were fatigue (32%) and neuropathy (22%). Kaplan Meier survival analysis showed median duration of survival was 15.9 months (95% CI 12.4–20.5) from first drug use. 1-year survival was 0.63 (95% CI 0.52–0.72). Post-docetaxel, 36 patients received second-line treatment, mostly with mitoxantrone (89%). Second-line response rates were 22%, and median duration of response was 4 months. Conclusions: In routine clinical practice, docetaxel is a well-tolerated regimen for the treatment of HRPC. Response rates and toxicity profiles were comparable to the randomized trials. However, compared with the TAX 327 clinical trial, survival was slightly shorter than expected (15.9 vs. 18.9 months), possibly due to inclusion of patients with poorer performance status and comorbidities, who may be excluded from clinical trials. Second-line response rates were also comparable with previous reports.

No significant financial relationships to disclose.

Phase II study of the angiogenesis inhibitor AZD2171 in first line, progressive, unresectable, advanced metastatic renal cell carcinoma (RCC): A trial of the PMH Phase II Consortium

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Background: AZD2171 is an oral, highly potent inhibitor of VEGFR1, VEGFR2, with activity also against cKit, PDGFRβ and Flt-4. We conducted a two-stage, phase II trial of AZD 2171 in first line advanced RCC, with a planned sample size of 37 pts, and a primary endpoint of tumor control rate (PR+SD). Methods: Pts had progressive, unresectable, advanced RCC, measurable disease, a performance status of ≤ 2 and no prior cytokine or antiangiogenic therapy. Pts received AZD2171 45 mg orally, daily, continuously (1cycle = 4wks) as monotherapy. Disease was evaluated with cross-sectional imaging every 8 wks. Functional DCE-MRI imaging was performed at baseline, 24h and 28d after the first dose. Pharmacokinetic studies were performed on day 8, 15 and 28. Results: From January- November 2006, 24 pts median (range) age 62 (44–80), were entered on study. Sixteen pts evaluable for response, 7 too early; 23 pts evaluable for toxicity; 1 pt inevaluable due to withdrawal. There have been 6 confirmed PR (6/16=38%), 1 unconfirmed PR, 5 SD, 4 PD. Tumor control rate 12/16=75%. Seventeen patients remain on treatment, 6 now off due to PD and 1 off due to consent withdrawal. Eighteen patients had dose reductions due to toxicity. Most common toxicities (any grade) were fatigue (21pts), voice alteration (14pts), hypertension (12pts), diarrhea (15pts), and increased creatinine (10pts). Common (>5% of cycles) grade 3+ adverse events were hypertension (5pts), joint pain (4pts), fatigue (7pts), dyspnea (2pts), increased ALT (2pts) and anorexia (3pts). Preliminary pK analysis is available on 6 patients: median (range) Tmax: 2hr (2- 6hr), Cmax: 107.8± 29.8 ng/ml, T1/2: 12.1 ± 2.2hr. Conclusion: AZD2171 is an active agent in first line, progressive, unresectable, advanced RCC with a partial response rate of 38% and tumor control rates of 75%. Accrual is ongoing with pharmacokinetics, functional imaging, and correlative studies. This agent warrants further investigation.

No significant financial relationships to disclose.

A phase II study of the antisense oligonucleotide GTI-2040 plus docetaxel and prednisone as first line treatment in hormone refractory prostate cancer (HRPC)

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Background: Despite initial responses to chemotherapy, median survival in HRPC remains a dismal 18 mos. Novel therapeutic approaches are clearly needed. The enzyme ribonucleotide reductase (RNR) composed of 2 subunits, R1 and R2 is essential for DNA synthesis and repair. The R2 subunit is often overexpressed in tumors increasing their malignant potential and promoting drug resistance. GTI-2040 (Lorus Therapeutics, Canada) is an antisense oligonucleotide to the R2 subunit downregulating its expression. In preclinical studies, GTI-2040 has shown antitumor activity in prostate cancer xenografts, synergy and non-overlapping toxicity with the taxanes. It is therefore a rational choice for combination with docetaxel in HRPC. Objectives: To determine efficacy of this regimen using PSA response rate. Secondary objectives include: duration of response, TTP, objective tumor response rate, safety and tolerability. Pharmacokinetic (PK) studies will be performed. PBMC will be used to determine RNR activity and R2 subunit quantitation. Methods: HRPC patients with PS 0–2, adequate organ function and no prior chemotherapy were treated with GTI-2040 5mg/kg/d continuous infusion for 14d, docetaxel 75 mg/m2 IV every 21d, and prednisone 5mg twice daily. Results: Twenty-two pts in 5 centers have been enrolled. Pts have received a total of 107 cycles to date. Median age 63 (52–77); median baseline PSA 140 (26–1256); ECOG 0:1:2: 14:7:1; prior radiotherapy in 14 pts. Pts received a median of 5 cycles (2–10). Grade 3/4 hematologic toxicities were lymphophenia (10pts), leukopenia (7pts), and neutropenia (7pts). Anemia (any grade) was seen in 19 pts across 92 cycles. Most frequent non-hematologic toxicities were fatigue and pain. PSA responses seen in 9/22 pts. Objective tumor response:1 PR, 9 SD, 3 PD, 3 off due to toxicity prior to objective response measurement, 3 no measureable lesions, 3 to be assessed. 19 pts off treatment: 9 PD, 4 toxicity (1 toxic death), 2 completed 10 cycles, 2 at investigator’s discretion and 2 withdrew consent. Three pts remain on study. Median TTP estimated at 17 wks. Accrual has been sufficient to meet stage 1 requirements. Final response, toxicity, pK, RNR and R2 subunit analysis will be available and presented.

No significant financial relationships to disclose.

Significance of left axis deviation in patients with chronic left bundle branch block

Forty-nine patients with chronic left bundle branch block and a normal frontal axis were compared with 53 patients with left bundle branch block and left axis deviation. The following clinical variables were more frequent (P less than 0.05) in patients with left axis deviation: greater age, exertional angina, congestive heart failure, cardiomegaly, cardiac functional class II to IV, coronary artery disease and presence of organic heart disease. Absence of organic heart disease (primary conduction disease) was seen only in patients with a normal axis. Patients with left axis deviation had longer (P less than 0.05) mean P-R, A-H and H-V intervals and atrial and atrioventricular (A-V) nodal effective refractory periods. All patients were prospectifely followed up for 30 to 2,271 days with a mean +/- standard error of the mean follo-up period of 538 +/- 72 for the group with a normal axis and 604 +/- 72 days for the group with left axis deviation (difference not significant). A-V block developed in three patients (6 percent) with left axis deviation and in none of those with a normal axis. The cumulative 4 year mortality rate for the entire group approached 75 percent. The patients with left axis deviation had greater cardiovascular mortality (P less than 0.05). In conclusion, among patients with left bundle branch block, those with left axis deviation have a greater incidence of myocardial dysfunction, more advanced conduction desease and greater cardiovascular mortality than those with a normal axis.