Chemotherapy in frail elderly patients with hormone-refractory prostate cancer: A "real world" experience

Metronomic Chemotherapy in Elderly Patients

PURPOSE OF REVIEW

This review describes the most relevant studies found in the scientific literature regarding metronomic chemotherapy (MCT) in the geriatric oncology population to support its use as a feasible treatment of care in the frail elderly patients.

RECENT FINDINGS

Recent years have seen a reevaluation of cancer chemotherapeutic drugs and MCT is an emerging schedule in phase II and III clinical trials. Ageing is one of the risk factors for the development of cancer, the incidence of whom increases dramatically in people who live longer. To date, standard oncological protocols involve chemotherapeutic drugs in short cycles of therapy at the maximum tolerated dose (MTD). Although these therapeutic regimens may be successful, they can cause important adverse drug reactions, especially in elderly or frail patients. MCT is a different modality of delivery of chemotherapeutic drugs (frequent low dose for prolonged time) and it looks at the overcoming of the limitations and disadvantages of MTD, in particular the toxicity aspect. We reviewed the experience of clinicians who have used MCT in clinical trials enrolling elderly patients with different cancer types.

Activity and safety of KEES - an oral multi-drug chemo-hormonal metronomic combination regimen in metastatic castration-resistant prostate cancer

BACKGROUND

Metastatic castration-resistant prostate cancer (mCRPC) remains a therapeutic challenge and evidence for late-line treatments in real-life is limited. The present study investigates the efficacy and safety of an oral metronomic chemo-hormonal regimen including cyclophosphamide, etoposide, estramustine, ketoconazole and prednisolone (KEES) administered in a consecutive biweekly schedule.

METHODS

A retrospective cohort study in two Swedish regions was conducted. Overall (OS) and progression-free survival (PFS), biochemical response rate (bRR) and toxicities were analyzed.

RESULTS

One hundred and twenty-three patients treated with KEES after initial treatment with at least a taxane or an androgen-receptor targeting agents (ARTA) were identified. Of those, 95 (77%) had received both agents and were the primary analysis population. Median (95% CI) OS and PFS in the pre-treated population were 12.3 (10.1-15.0) and 4.4 (3.8-5.5) months, respectively. Biochemical response, defined as ≥ 50% prostate-specific antigen (PSA) reduction, occurred in 26 patients (29%), and any PSA reduction in 59 (65%). PFS was independent of prior treatments used, and KEES seemed to be effective in late treatment lines. The bRR was higher compared to historical data of metronomic treatments in docetaxel and ARTA pre-treated populations. In multivariable analyses, performance status (PS) ≥ 2 and increasing alkaline phosphatase (ALP) predicted for worse OS. Nausea, fatigue, thromboembolic events and bone marrow suppression were the predominant toxicities.

CONCLUSIONS

KEES demonstrated meaningful efficacy in heavily pre-treated CRPC patients, especially those with PS 0-1 and lower baseline ALP, and had an acceptable toxicity profile.

LncRNA SSTR5-AS1 as a Prognostic Marker Promotes Cell Proliferation and Epithelial-to-Mesenchymal Transition in Prostate Cancer

This study is aimed to investigate the clinical significance and biological function of long non-coding RNA somatostatin receptor 5 antisense RNA 1 (SSTR5-AS1) in prostate cancer (PCa). Here, we found that SSTR5-AS1 expression was upregulated in PCa tissues compared with adjacent tissues using quantitative real time PCR analysis. The results from Chi-square test showed that increased SSTR5-AS1 expression levels were correlated with preoperative prostate specific antigen, tumor stage and lymph node metastasis. Kaplan-Meier survival curve described patients with high SSTR5-AS1 expression level showed poor survival. Univariate and multivariate cox regression analysis further identified SSTR5-AS1 expression as a poor independent prognostic factor for PCa patients. Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine incorporation assay, wound-healing assay and Transwell assay were performed to investigate the functional role of SSTR5-AS1 in PCa cells. The in vitro results indicated that SSTR5-AS1 knockdown inhibited, while SSTR5-AS1 overexpression promoted the proliferation, migration, and invasion of PCa cells. At molecular level, SSTR5-AS1 knockdown downregulated the protein levels of proliferating cell nuclear antigen, N-cadherin and vimentin, and upregulated E-cadherin expression in PC-3 cells. SSTR5-AS1 overexpression obtained opposite results on these protein markers in DU145 cells. In conclusion, these findings indicated that SSTR5-AS1 promotes PCa cell behaviors, which might provide a potential therapeutic target for PCa patients.

Metronomic Chemotherapy for Advanced Prostate Cancer: A Literature Review

Metastatic castration-resistant prostate cancer (mCRPC) is the ultimately lethal form of prostate cancer. Docetaxel chemotherapy was the first life-prolonging treatment for mCRPC; however, the standard maximally tolerated dose (MTD) docetaxel regimen is often not considered for patients with mCRPC who are older and/or frail due to its toxicity. Low-dose metronomic chemotherapy (LDMC) is the frequent administration of typically oral and off-patent chemotherapeutics at low doses, which is associated with a superior safety profile and higher tolerability than MTD chemotherapy. We conducted a systematic literature review using the PUBMED, EMBASE, and MEDLINE electronic databases to identify clinical studies that examined the impact of LDMC on patients with advanced prostate cancer. The search identified 30 reports that retrospectively or prospectively investigated LDMC, 29 of which focused on mCRPC. Cyclophosphamide was the most commonly used agent integrated into 27/30 (90%) of LDMC regimens. LDMC resulted in a clinical benefit rate of 56.8 ± 24.5% across all studies. Overall, there were only a few non-hematological grade 3 or 4 adverse events reported. As such, LDMC is a well-tolerated treatment option for patients with mCRPC, including those who are older and frail. Furthermore, LDMC is considered more affordable than conventional mCRPC therapies. However, prospective phase III trials are needed to further characterize the efficacy and safety of LDMC in mCRPC before its use in practice.

Efficacy and safety of Androgen Deprivation Therapy (ADT) combined with modified docetaxel chemotherapy versus ADT combined with standard docetaxel chemotherapy in patients with metastatic castration-resistant prostate cancer: study protocol for a multicentre prospective randomized controlled trial

Background

Androgen deprivation therapy (ADT) combined with docetaxel chemotherapy is the standard treatment for metastatic castration-resistant prostate cancer (mCRPC) patients. However, mCRPC patients are mainly frail elderly men, constantly accompanied by comorbidities and showing poor tolerance to standard docetaxel chemotherapy. Some exploratory studies administering modified chemotherapy regimens have reported noninferior oncologic outcomes with fewer adverse events, yet most are retrospective or small studies, and prospective randomized controlled trials have rarely been conducted. Therefore, we designed this modified docetaxel chemotherapy regimen in patients with mCRPC, aiming to evaluate its efficacy and safety compared with the standard docetaxel chemotherapy regimen.

Methods

This is an open-label, multi-institutional, prospective, randomized non-inferiority trial. A total of 128 patients with mCRPC will be randomized to receive ADT combined with modified docetaxel chemotherapy (experimental group, n=64) or ADT combined with standard docetaxel chemotherapy (control group, n=64). Patients in the experimental group will receive a modified regimen with docetaxel 40 mg/m2 on the 1st day and 35 mg/m2 on the 8th day, repeated every 21 days. The primary endpoint is progression-free survival at 2 years. Secondary endpoints include overall survival, prostate-specific antigen response rate, pain response rate, toxicity and quality of life.

Discussion

The expected benefit for the patient in the experimental arm is noninferior efficacy with decreased toxicity and improved quality of life compared with that in the control arm. To the best of our knowledge, this will be the first multicentre prospective randomized study to assess the efficacy and safety of modified docetaxel chemotherapy in patients with mCRPC in China. The results of this trial may provide benefit to mCRPC patients, especially those with poor performance.

Trial registration

chictr.org.cn Identifier: ChiCTR2100046636 (May 24, 2021). Ongoing study.

Which Way to Choose for the Treatment of Metastatic Prostate Cancer: A Case Report and Literature Review

Background

Prostate cancer (PCa) is the second most common cancer among males in the world and the majority of patients will eventually progress to the metastatic phase. How to choose an effective way for the treatment of metastatic PCa, especially in the later stage of the disease is still confusing. Herein we reported the case of a patient diagnosed with metastatic PCa and conducted a literature review on this issue.

Case Presentation

A 57-year-old man with metastatic PCa had been managed by Dr. J.P. since April 2012 when the patient was admitted to the Third Affiliated Hospital of Sun Yat-sen University by aggravating frequent urination and dysuria. The prostate-specific antigen (PSA) concentration was 140 ng/ml, and the diagnosis of PCa was confirmed by prostate biopsy, with Gleason score 4 + 5 = 9. Chest CT and bone scan indicated multiple metastases in the lungs and bones. Triptorelin, bicalutamide, zoledronic acid, and docetaxel were then administered, six cycles later, the metastatic tumors in the lungs disappeared and those in the bones lessened significantly, along with a remarkable reduction in PSA level (< 2 ng/ml). Intermittent androgen deprivation was subsequently conducted until August 2018, when the serum PSA level was found to be 250 ng/ml, again docetaxel 75 mg/m² was administered immediately but the patient was intolerant this time. Instead, abiraterone was administered until March 2019 because of intolerable gastrointestinal side-effects and increasing PSA level. In October 2019, the patient came to our center, a modified approach of docetaxel (day 1 40 mg/m² + day 8 35 mg/m²) was administered. Luckily, the PSA level decreased rapidly, the bone pain was greatly relieved, and no obvious side effects occurred. However, four cycles later, docetaxel failed to work anymore, the metastatic tumor in the liver progressed. We proposed several regimens as alternatives, but they were soon denied due to the high prices or unavailability or uncertain effect of the drugs. In addition, the patient’s condition deteriorated speedily and can no longer bear any aggressive treatment. Finally, the patient died of multiple organ failure in August 2020.

Conclusion

The experiences of this case provide valuable evidence and reference for the treatment choices of metastatic PCa, in some circumstances modified and advanced regimens may produce unexpected effects.

De-escalating cancer treatments during COVID 19 pandemic: Is metronomic chemotherapy a reasonable option?

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COVID 19 pandemic represents an emergency for public health services.

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The reorganization of the healthcare system has had an important impact on the management of cancer patients.

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Oral treatments and de-escalation strategies are encouraged.

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Oral metronomic chemotherapy could be a reasonable treatment option in some cancer patients subgroups during COVID 19 pandemic.

COVID 19 pandemic represents an emergency for public health services and containment measures to reduce the risk of infection have been promptly activated worldwide.

The healthcare systems reorganization has had a major impact on the management of cancer patients who are considered at high risk of infection.

Recommendations and guidelines on how to manage cancer patients during COVID 19 pandemic have been published. Oral administration of chemotherapy is recommended to limit the access of cancer patients to hospital facilities and in some cases to guarantee the continuum of care.

Low-dose metronomic administration of chemotherapy with different drugs and schedules has emerged in the last years as a possible alternative to conventional chemotherapy, due to its promising tumor control rates and excellent safety profiles. Moreover, given that many metronomic schedules use the oral route administration, it could represent a therapeutic strategy to ensure continuum of cancer care during COVID 19 pandemic.

In this review we have selected all the clinical studies that have used the metronomic strategy, especially with oral drugs, in order to identify the subgroups of cancer patients who can benefit most from a metronomic approach even during COVID 19 pandemic.

Pharmacotherapeutic strategies for castrate-resistant prostate cancer

INTRODUCTION

Metastatic castration-resistant prostate cancer (CRPC) is a potentially symptomatic disease with an eventual lethal outcome. Novel pharmaceutical agents are continuously studied with encouraging results in CRPC.

AREAS COVERED

In this perspective, the authors present established and promising pharmacotherapeutic strategies for the management of CRPC; both with and without metastases. Apart from the different treatment strategies, the authors present the relevant sequence of treatment through disease progression.

EXPERT OPINION

Usually, docetaxel should be considered the first line treatment in mCRPC. Abiraterone acetate (AA) plus prednisone or enzalutamide (ENZ) could be alternative treatments in chemotherapy naïve patients. Sipuleucel-T has been approved for the treatment of asymptomatic or minimally symptomatic mCRPC. Ra-223 has been approved for patients with mCRPC with symptomatic bone metastases (not visceral metastases). Cabazitaxel has been approved as the second line treatment to docetaxel in mCRPC. No differences in the overall survival has been observed between sequences starting with docetaxel versus AA/ENZ. Between AA-to-ENZ and ENZ-to-AA sequence, the AA-to-ENZ sequence appeared to be more favorable than the ENZ-to-AA regarding progression-free survival but not overall survival. Carbazitaxel seemed to retain its activity regardless of the treatment sequence. Of note, ENZ and apalutamide have been approved in non-metastatic CRPC.

Is there still a place for vinorelbine in advanced metastatic castration resistant prostate cancer?

The aim of this paper was to evaluate the activity and tolerability of oral vinorelbine in patients with advanced castration resistant prostate cancer (CRPC) who progressed after a minimum of three lines including: abiraterone acetate, docetaxel, cabazitaxel, and enzalutamide.Treatment consisted of weekly oral vinorelbine 60 mg/m. Chemotherapy was administered until disease progression or unacceptable toxicity.Twenty-six patients received vinorelbine: their median age was 74 years (range 58-84 years). Twenty-four (92.3%) patients had bone metastases. A decrease in PSA levels ≥50% was observed in 2 patients (7.7%). Among the subjects who were symptomatic at baseline, pain was reduced in 3 patients (13.6%) with a significant decrease in analgesic use. Median progression-free survival was 9 weeks (95% CI: 7 to 11) and median overall survival was 17 weeks (95% CI: 12 to 22). Treatment was well tolerated, and no grade 4 toxicities were observed.Our findings do not suggest the use of oral vinorelbine on a weekly schedule, in CRPC heavily pre-treated.

Metronomic Chemotherapy: A Systematic Review of the Literature and Clinical Experience

Metronomic chemotherapy, continuous and dose-dense administration of chemotherapeutic drugs with lowered doses, is being evaluated for substituting, augmenting, or appending conventional maximum tolerated dose regimens, with preclinical and clinical studies for the past few decades. To date, the principle mechanisms of its action include impeding tumoral angiogenesis and modulation of hosts' immune system, affecting directly tumor cells, their progenitors, and neighboring stromal cells. Its better toxicity profile, lower cost, and easier use are main advantages over conventional therapies. The evidence of metronomic chemotherapy for personalized medicine is growing, starting with unfit elderly patients and also for palliative treatment. The literature reviewed in this article mainly demonstrates that metronomic chemotherapy is advantageous for selected patients and for certain types of malignancies, which make it a promising therapeutic approach for filling in the gaps. More clinical studies are needed to establish a solidified role for metronomic chemotherapy with other treatment models in modern cancer management.