Adjuvant Systemic Therapies in Patients with Colorectal Cancer: An Audit on Clinical Practice in Italy

Aims and Background

Rarely are conclusions from clinical trials summarized in international consensus conferences and promptly transferred to patient care. The adjuvant therapy for colorectal cancer used in daily clinical practice in Italy is described and compared with the recommendations of the 1990 NIH Consensus Conference.

Patients and Methods

We audited prescriptions of adjuvant systemic therapies for Italian colorectal cancer patients in 82 centers during a fixed one-week period.

Results

Among 434 patients receiving adjuvant chemotherapy there were 139 (42.5%) colon cancer patients with N- and 169 (51.7%) with N+ regional nodal involvement. Treatment at academic centers, a young age, T4 and a low total number of lymph nodes removed at surgery were the factors potentially justifying the decision for adjuvant chemotherapy in stage II colon cancer patients. The most common chemotherapy used was a bolus of 5-fluorouracil/folinic acid for 6 months (75.8%). Adjuvant radiotherapy was not administered to 37 (38.5%) of 96 patients with stage II and III rectal cancer.

Conclusions

The study shows that a substantial proportion of patients on adjuvant treatment at a certain time point in a large enough sample of Italian centers are stage II (potential over-treatment) and that an under-treatment of stage II and III rectal cancer patients (lack of radiotherapy) occurs too often in daily clinical practice in this country.

Targeting the androgen receptor pathway in castration-resistant prostate cancer: progresses and prospects

Androgen receptor (AR) signaling is a critical pathway for prostate cancer cells, and androgen-deprivation therapy (ADT) remains the principal treatment for patients with locally advanced and metastatic disease. However, over time, most tumors become resistant to ADT. The view of castration-resistant prostate cancer (CRPC) has changed dramatically in the last several years. Progress in understanding the disease biology and mechanisms of castration resistance led to significant advancements and to paradigm shift in the treatment. Accumulating evidence showed that prostate cancers develop adaptive mechanisms for maintaining AR signaling to allow for survival and further evolution. The aim of this review is to summarize molecular mechanisms of castration resistance and provide an update in the development of novel agents and strategies to more effectively target the AR signaling pathway.

Androgen receptor expression in circulating tumour cells from castration-resistant prostate cancer patients treated with novel endocrine agents

BACKGROUND

Abiraterone and enzalutamide are novel endocrine treatments that abrogate androgen receptor (AR) signalling in castration-resistant prostate cancer (CRPC). Here, we developed a circulating tumour cells (CTCs)-based assay to evaluate AR expression in real-time in CRPC and investigated nuclear AR expression in CTCs in patients treated with enzalutamide and abiraterone.

METHODS

CTCs were captured and characterised using the CellSearch system. An automated algorithm to identify CTCs and quantify AR expression was employed. The primary aim was to evaluate the association between CTC AR expression and prior treatment with abiraterone or enzalutamide.

RESULTS

AR expression in CTCs was evaluated in 94 samples from 48 metastatic CRPC patients. We observed large intra-patient heterogeneity of AR expression in CTCs. Prior exposure to abiraterone or enzalutamide was not associated with a change in CTCs AR expression (median intensity and distribution of AR-positive classes). In support of this, we also confirmed maintained nuclear AR expression in tissue samples collected after progression on abiraterone. AR staining also identified additional AR-positive CD45-negative circulating cells that were CK-negative/weak and therefore missed using standard protocols. The number of these events correlated with traditional CTCs and was associated with worse outcome on univariate analysis.

CONCLUSIONS

We developed a non-invasive method to monitor AR nuclear expression in CTCs. Our studies confirm nuclear AR expression in CRPC patients progressing on novel endocrine treatments. Owing to the significant heterogeneity of AR expression in CTCs, studies in larger cohorts of patients are required to identify associations with outcome.

Baseline neutrophil-lymphocyte ratio (NLR) is associated with survival and response to treatment with second-line chemotherapy for advanced prostate cancer independent of baseline steroid use

BACKGROUND

The neutrophil-lymphocyte ratio (NLR), proposed as an indicator of cancer-related inflammation, has known prognostic value in prostate cancer. We examine its association with survival (OS) and response in patients treated with second-line chemotherapy.

METHODS

We analysed patients with metastatic castration-resistant prostate cancer (mCRPC) treated in the TROPIC trial, evaluating cabazitaxel versus mitoxantrone. Cox regression models were used to investigate the association of baseline NLR (BLNLR) with OS and the significance of a change in NLR count with treatment. Logistic regression models were used to determine the association of BLNLR counts with prostate specific antigen (PSA) and RECIST responses. The optimal NLR cut-off was established based on the concordance index of different values.

RESULTS

Data from 755, 654 and 405 patients was available for OS, PSA and RECIST response analysis respectively. Median OS was 14.0 months [95% confidence interval (CI) 13.2-14.8]. Median NLR was 2.9 (IQR: 1.9-5.1). BLNLR was associated with survival (HR 1.5, 95% CI 1.1-2.1, P = 0.011) in multivariable analysis (MVA) independently of variables included in the Halabi nomogram, treatment arm and corticosteroid use. The optimal cut-off for a dichotomous NLR was selected at 3.0 based on its higher c-index related to survival. BLNLR ≥3.0 was associated with lower PSA response (40.1% versus 59.9%; P < 0.001) and RECIST response (7.7% versus 15.6%, P = 0.022) in MVA. Conversion from high (≥3) to low (<3) NLR was associated with improved survival (HR 0.66; 95% CI 0.51-0.85; P = 0.001) and higher PSA response rates (66.4% versus 33.6%; P = 0.000). Use of corticosteroids at baseline did not modify the association between NLR and survival.

CONCLUSIONS

NLR is a valid prognostic biomarker in CRPC and is associated with survival, PSA and RECIST responses in patients treated with second-line chemotherapy. Changes in NLR counts with treatment may indicate benefit. NLR prognostic value is independent of prior use of corticosteroids.

CLINICALTRIALSGOV

NCT00417079.

Tumour responses following a steroid switch from prednisone to dexamethasone in castration-resistant prostate cancer patients progressing on abiraterone

BACKGROUND

Abiraterone is a CYP17A1 inhibitor that improves survival in castration-resistant prostate cancer (CRPC). Abiraterone is licensed in combination with prednisone 5 mg twice daily to prevent a syndrome of secondary mineralocorticoid excess. We hypothesised that a 'steroid switch' from prednisone to dexamethasone would induce secondary responses in patients progressing on abiraterone and prednisone 5 mg b.i.d.

METHODS

We performed a 'steroid switch' in patients with CRPC at PSA progression on abiraterone and prednisolone. Patients were monitored for secondary declines in PSA, radiological tumour regression and toxicity.

RESULTS

A retrospective analysis of 30 CRPC patients who underwent a steroid switch from prednisolone to dexamethasone while on abiraterone was performed. A total of six patients (20%) had a ⩾50% PSA decline that was confirmed by a second PSA level at least 3 weeks later. In all, 11 patients (39.2%) had a confirmed ⩾30% PSA decline. Median time to PSA progression on abiraterone and dexamethasone was 11.7 weeks (95% CI: 8.6-14.8 weeks) in the whole cohort and 27.6 weeks (95% CI: 14.5-40.7 weeks) in patients who achieved a confirmed 50% PSA decline. Nine patients had RECIST evaluable disease: two of these patients had RECIST partial response, six patients had stable disease and one patient had progressive disease at the first imaging assessment. Treatment was well tolerated, with no grade 3 and grade 4 adverse events. One patient had to be reverted to prednisolone because of grade 2 hypotension.

CONCLUSIONS

Durable PSA responses occur in up to 40% of patients following a 'steroid switch' for PSA progression on abiraterone and prednisone. Studies are ongoing to elucidate the mechanisms underlying this response.

Visceral disease in castration-resistant prostate cancer

Metastatic involvement of the viscera in men with advanced castration-resistant prostate cancer (CRPC) has been poorly characterised to date. In 359 CRPC patients treated between June 2003 and December 2011, the frequency of radiologically detected visceral metastases before death was 32%. Of the 92 patients with computed tomography performed within 3 mo of death, 49% had visceral metastases. Visceral metastases most commonly involved the liver (20%) and lung (13%). Median survival from diagnosis of visceral disease was 7.1 mo (95% confidence interval, 5.9-8.3). Survival was affected by the degree of bone involvement at detection of visceral disease, varying from 6.1 mo in men with more than six bone metastases to 18.2 mo in men with no bone metastases (p=0.001). Heterogeneity was noted in clinical phenotypes and prostate-specific antigen trends at development of visceral metastases. Visceral metastases are now more commonly detected in men with CRPC, likely due to the introduction of novel survival-prolonging treatments.

First-in-human Phase I study of EZN-4176, a locked nucleic acid antisense oligonucleotide to exon 4 of the androgen receptor mRNA in patients with castration-resistant prostate cancer

BACKGROUND

Prostate cancer remains dependent of androgen receptor (AR) signalling, even after emergence of castration resistance. EZN-4176 is a third-generation antisense oligonucleotide that binds to the hinge region (exon 4) of AR mRNA resulting in full-length AR mRNA degradation and decreased AR protein expression. This Phase I study aimed to evaluate EZN-4176 in men with castration-resistant prostate cancer (CRPC).

METHODS

Patients with progressing CRPC were eligible; prior abiraterone and enzalutamide treatment were allowed. EZN-4176 was administered as a weekly (QW) 1-h intravenous infusion. The starting dose was 0.5 mg kg(-1) with a 4-week dose-limiting toxicity (DLT) period and a 3+3 modified Fibonacci dose escalation design. After determination of the DLT for weekly administration, an every 2 weeks schedule was initiated.

RESULTS

A total of 22 patients were treated with EZN-4176. At 10 mg kg(-1) QW, two DLTs were observed due to grade 3-4 ALT or AST elevation. No confirmed biochemical or soft tissue responses were observed. Of eight patients with <5 circulating tumour cells at baseline, a conversion to <5 was observed in three (38%) patients. The most common EZN-4176-related toxicities (all grades) were fatigue (59%), reversible abnormalities in liver function tests ALT (41%) and AST (41%) and infusion-related reactions including chills (36%) and pyrexia (14%).

CONCLUSION

Activity of EZN-4176 at the doses and schedules explored was minimal. The highest dose of 10 mg kg(-1) QW was associated with significant but reversible transaminase elevation.

Antitumour activity of enzalutamide (MDV3100) in patients with metastatic castration-resistant prostate cancer (CRPC) pre-treated with docetaxel and abiraterone

BACKGROUND

The new generation anti-androgen enzalutamide and the potent CYP17 inhibitor abiraterone have both demonstrated survival benefits in patients with metastatic castration-resistant prostate cancer (CRPC) progressing after docetaxel. Preliminary data on the antitumour activity of abiraterone after enzalutamide have suggested limited activity. The antitumour activity and safety of enzalutamide after abiraterone in metastatic CRPC patients is still unknown.

PATIENTS AND METHODS

We retrospectively identified patients treated with docetaxel and abiraterone prior to enzalutamide to investigate the activity and safety of enzalutamide in a more advanced setting. Prostate specific antigen (PSA), radiological and clinical assessments were analysed.

RESULTS

39 patients with metastatic CRPC were identified for this analysis (median age 70years, range: 54-85years). Overall 16 patients (41%) had a confirmed PSA decline of at least 30%. Confirmed PSA declines of ⩾50% and ⩾90% were achieved in 5/39 (12.8%) and 1/39 (2.5%) respectively. Of the 15 patients who responded to abiraterone, two (13.3%) also had a confirmed ⩾50% PSA decline on subsequent enzalutamide. Among the 22 abiraterone-refractory patients, two (9%) achieved a confirmed ⩾50% PSA decline on enzalutamide.

CONCLUSION

Our preliminary case series data suggest limited activity of enzalutamide in the post-docetaxel and post-abiraterone patient population.

Antitumour activity of abiraterone and diethylstilboestrol when administered sequentially to men with castration-resistant prostate cancer

BACKGROUND

Abiraterone is a standard treatment for men with castration-resistant prostate cancer (CRPC). We evaluated the antitumour activity of abiraterone following the synthetic oestrogen diethylstilboestrol (DES).

METHODS

Castration-resistant prostate cancer patients treated with abiraterone were identified. Demographics, response variables and survival data were recorded.

RESULTS

Two-hundred and seventy-four patients received abiraterone, 114 (41.6%) after DES. Pre-chemotherapy abiraterone resulted in ≥50% PSA declines in 35/41 (85.4%) DES-naïve and 20/27 (74.1%) DES-treated patients. Post-docetaxel abiraterone resulted in ≥50% PSA declines in 40/113 (35.4%) DES-naïve and 23/81 (28.4%) DES-treated patients. Time to PSA progression was similar regardless of prior DES.

CONCLUSION

Abiraterone has important antitumour activity in men with CRPC even after DES exposure.

Weekly Vinorelbine and Docetaxel as Second-Line Chemotherapy for Pretreated Non-Small Cell Lung Cancer Patients: a Phase I-II Trial

Docetaxel was proven to be effective as second-line therapy for patients with advanced NSCLC after failure of platinum-based front-line chemotherapy. We designed this phase I/II study to define the Maximum Tolerated Dose of weekly docetaxel combined with weekly vinorelbine, and subsequently evaluate tolerability and activity of this schedule in NSCLC patients who were progressive after treatment with either cisplatin and gemcitabine or carboplatin and paclitaxel regimens. To be eligible for the study, patients were required to have a WHO performance status < or =2, failure after at least two cycles of first platinum-based chemotherapy, and no prior treatment with docetaxel and vinorelbine. A total of 27 patients were enrolled in this phase I/II study. A weekly docetaxel dose of 25 mg/m2 was recommended in combination with fixed vinorelbine dose of 20 mg/m2, and 24 patients were treated at this dose level. Severe neutropenia (62%) and febrile neutropenia (29%) were the most frequent toxicities, with 83% of patients requiring dose modification or delay. In the phase II study, 5 (21%) patients obtained a partial response, 8 (33%) patients had stable disease, whereas 10 (42%) patients progressed. After a median follow-up of 18.7 months, median survival was 8 months, with 30% surviving at 1 year. Regardless of the use of weekly docetaxel schedule, this regimen was highly myelosuppressive, and did not seem to improve response rate and survival compared to single-agent docetaxel. No further developments of this schedule are warranted.

Association between a high BK virus load in urine samples of patients with graft-versus-host disease and development of hemorrhagic cystitis after hematopoietic stem cell transplantation

BK virus (BKV) load in urine alone or in combination with acute graft-versus-host disease (GVHD) was correlated to development of hemorrhagic cystitis (HC). BKV load in combination with acute GVHD discriminated the best, while BKV and viral load alone, but not GVHD, still showed predictive ability for HC.