Cure in Advanced Renal Cell Cancer: Is It an Achievable Goal?

BACKGROUND: Immunotherapy has historically been of interest in the management of metastatic renal cell cancer (mRCC) because of its relative chemoresistance and the reproducible but low incidence of spontaneous remission in metastatic disease. Recently, targeted immunotherapies in the form of checkpoint inhibitors have shown durable responses in approximately 20%-30% of patients with solid tumors, with a much more acceptable side-effect profile. Anti-programmed death receptor 1 (PD-1)/programmed death receptor ligand 1 antibodies rely on the presence of host T cells in the tumor microenvironment to be stimulated in order to activate an antitumor response. The presence of tumor antigens augments this stimulation. This has led to further research into combination therapy with anti-PD-1 inhibitors and radiotherapy, chemotherapy, or targeted therapy with the aim of increasing the response rate to these agents. MATERIALS AND METHODS: We describe three cases of patients with mRCC treated with anti-PD-1 antibody therapy in combination with targeted therapy (bevacizumab), anti-cytotoxic T lymphocyte antigen 4 therapy (ipilimumab), or radiotherapy. We perform a comprehensive literature review on combination immunotherapy and the scope for the future. RESULTS: Two patients had a complete clinical response within 3 months of commencing treatment. The third patient had a further significant response to radiotherapy outside the field of treatment after initial response to anti-PD-1 therapy, which lasted for over 12 months. CONCLUSION: We are now in the era of immunotherapy with promising results in select patients. However, the number of complete remissions with single agents are low. This report demonstrates the potential for combination therapy in mRCC to produce complete responses and improved survival rates. Whether these results equate to cure in a subset of patients requires longer follow-up. Further evaluation of dosing regimens, sequencing methods, and biomarkers to select patient population is required to advance this treatment strategy. IMPLICATIONS FOR PRACTICE: Multiple phase I-III studies exploring the benefit of combination immunotherapy are currently under way. Further research into predictive biomarkers to identify the cohort of patients who gain this benefit is pertinent. This case series demonstrates that the combination of immunotherapy with other treatments can lead to complete responses, even in patients with initially bulky disease. Combination therapy with immunotherapy seems to cause more durable responses in patients with metastatic renal cell cancer compared with monotherapy. Significantly longer follow-up is necessary to determine whether durable complete response confers a cure in a select group of patients.

Coronary Flow Velocity Reserve Declines After Anthracycline Therapy in Breast Cancer Patients.

Anthracycline therapy (ANT) is associated with cancer therapy-related cardiac dysfunction. Coronary flow velocity reserve (CFVR) has shown prognostic utility in non-cancer cohorts, but no data have been obtained in a cardio-oncology setting. We investigated the acute effect of ANT on CFVR in breast cancer patients. A total of 12 female breast cancer patients undergoing ANT had pre- and post-ANT CFVR assessment. A significant decline in CFVR occurred (baseline: 2.66 ± 0.41 vs post-ANT: 2.47 ± 0.37, P = 0.016). This prospective study is the first to identify ANT-related coronary physiology changes in humans. Further studies are required to determine their clinical significance.

Le traitement par l'anthracycline est associé à une dysfonction cardiaque liée au traitement anticancéreux. La réserve de débit coronaire a démontré son utilité pronostique dans les cohortes sans cancer, mais aucune donnée n'a été obtenue dans un contexte de cardio-oncologie. Nous avons étudié l'effet aigu de l'anthracycline sur la réserve de débit coronaire chez des patientes atteintes d'un cancer du sein. La réserve de débit coronaire a été évaluée avant et après le traitement par l'anthracycline chez un total de 12 femmes atteintes d'un cancer du sein. Un déclin important de la réserve de débit coronaire est survenu (valeur initiale de 2,66 ± 0,41 par rapport à 2,47 ± 0,37 après le traitement par l'anthracycline, p = 0,016). Cette étude prospective est la première à déceler des changements dans la physiologie coronarienne liés à l'anthracycline chez les humains. D'autres études sont nécessaires pour en déterminer la portée clinique.

Case Series: "Silent" Spinal Epidural Metastases in Metastatic Castrate-Resistant Prostate Cancer.

Introduction: Spinal epidural metastases (SEM) are an uncommon phenomenon and traditionally occur as a preterminal event in heavily pre-treated patients. The introduction of novel anti-androgen therapies, such as enzalutamide and abiraterone acetate, has greatly improved the survival of patients with metastatic prostate cancer but may be changing the pattern of disease. Case Presentation: Four patients diagnosed with metastatic castrate-resistant prostate cancer (CRPC) were commenced on enzalutamide prior to chemotherapy. Baseline scans in all patients demonstrated extensive bony disease and lymph node involvement. All patients experienced a moderate initial PSA response to treatment (median PSA at baseline 53.5 ng/mL to median nadir 24.5 ng/mL). In all four cases, clinical presentation of spinal cord compression was unexpected with no prodromal neurological symptoms, PSA levels either stable or slowly rising, and CT scans and whole-body bone scans showing stable disease at other metastatic sites. Whole-spine MRI on presentation of neurological deficits showed epidural and dural metastases on the background of stable bone disease. Spinal cord compression occurred at a median of 11.4 months after starting enzalutamide. Conclusion: Clinicians should be aware of this change in the pattern of CRPC in patients treated with novel anti-androgen therapy. Onset of "silent" spinal cord compression due to SEM rather than bone metastases, can occur relatively early with minimal warning despite stable disease on PSA and standard imaging. Differential progression in nontraditional sites suggests that research into the androgen microenvironment in a wide range of tissue sites should be undertaken, and may explain why prostate cancer metastasizes preferentially to bone and lymph nodes.

Treatment Exposure and Discontinuation in the PALbociclib CoLlaborative Adjuvant Study of Palbociclib With Adjuvant Endocrine Therapy for Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Early Breast Cancer (PALLAS/AFT-05/ABCSG-42/BIG-14-03).

PURPOSE: The PALLAS study investigated whether the addition of palbociclib, an oral CDK4/6 inhibitor, to adjuvant endocrine therapy (ET) improves invasive disease-free survival (iDFS) in early hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. In this analysis, we evaluated palbociclib exposure and discontinuation in PALLAS. METHODS: Patients with stage II-III HR+, HER2- disease were randomly assigned to 2 years of palbociclib with adjuvant ET versus ET alone. The primary objective was to compare iDFS between arms. Continuous monitoring of toxicity, dose modifications, and early discontinuation was performed. Association of baseline covariates with time to palbociclib reduction and discontinuation was analyzed with multivariable competing risk models. Landmark and inverse probability weighted per-protocol analyses were performed to assess the impact of drug persistence and exposure on iDFS. RESULTS: Of the 5,743 patient analysis population (2,840 initiating palbociclib), 1,199 (42.2%) stopped palbociclib before 2 years, the majority (772, 27.2%) for adverse effects, most commonly neutropenia and fatigue. Discontinuation of ET did not differ between arms. Discontinuations for non-protocol-defined reasons were greater in the first 3 months of palbociclib, and in the first calendar year of accrual, and declined over time. No significant relationship was seen between longer palbociclib duration or ≥ 70% exposure intensity and improved iDFS. In the weighted per-protocol analysis, no improvement in iDFS was observed in patients receiving palbociclib versus not (hazard ratio 0.89; 95% CI, 0.72 to 1.11). CONCLUSION: Despite observed rates of discontinuation in PALLAS, analyses suggest that the lack of significant iDFS difference between arms was not directly related to inadequate palbociclib exposure. However, the discontinuation rate illustrates the challenge of introducing novel adjuvant treatments, and the need for interventions to improve persistence with oral cancer therapies.

Radioimmunotherapy for solid tumors: spotlight on Glypican-1 as a radioimmunotherapy target.

Radioimmunotherapy (i.e., the use of radiolabeled tumor targeting antibodies) is an emerging approach for the diagnosis, therapy, and monitoring of solid tumors. Often using paired agents, each targeting the same tumor molecule, but labelled with an imaging or therapeutic isotope, radioimmunotherapy has achieved promising clinical results in relatively radio-resistant solid tumors such as prostate. Several approaches to optimize therapeutic efficacy, such as dose fractionation and personalized dosimetry, have seen clinical success. The clinical use and optimization of a radioimmunotherapy approach is, in part, influenced by the targeted tumor antigen, several of which have been proposed for different solid tumors. Glypican-1 (GPC-1) is a heparan sulfate proteoglycan that is expressed in a variety of solid tumors, but whose expression is restricted in normal adult tissue. Here, we discuss the preclinical and clinical evidence for the potential of GPC-1 as a radioimmunotherapy target. We describe the current treatment paradigm for several solid tumors expressing GPC-1 and suggest the potential clinical utility of a GPC-1 directed radioimmunotherapy for these tumors.

RetroSPECT: Gallium-67 as a Long-Lived Imaging Agent for Theranostics.

A limitation to the wider introduction of personalised dosimetry in theranostics is the relative paucity of imaging radionuclides with suitable physical and chemical properties to be paired with a long-lived therapeutic partner. As most of the beta-emitting therapeutic radionuclides emit gamma radiation as well they could potentially be used as the imaging radionuclide as well as the therapeutic radionuclide. However, the downsides are that the beta radiation will deliver a significant radiation dose as part of the treatment planning procedure, and the gamma radiation branching ratio is often quite low. Gallium-67 has been in use in nuclear medicine for over 50 years. However, the tremendous interest in gallium imaging in theranostics in recent times has focused on the PET radionuclide gallium-68. In this article it is suggested that the longer-lived gallium-67, which has desirable characteristics for imaging with the gamma camera and a suitably long half-life to match biological timescales for drug uptake and turnover, has been overlooked, in particular, for treatment planning with radionuclide therapy. Gallium-67 could also allow non-PET facilities to participate in theranostic imaging prior to treatment or for monitoring response after therapy. Gallium-67 could play a niche role in the future development of personalised medicine with theranostics.

Safety and tolerability of Miltuximab® - a first in human study in patients with advanced solid cancers.

OBJECTIVES: Miltuximab® is a chimeric antibody targeting Glypican-1 (GPC-1), a cell surface antigen which is overexpressed in solid cancers. Miltuximab® has shown promising safety and efficacy in radioimmunotherapy models of prostate cancer. This first in human study used Miltuximab® radiolabelled with Gallium-67 ([67Ga]Ga-DOTA-Miltuximab®). The primary study endpoint was to establish safety and tolerability of Miltuximab®. Secondary endpoints were biodistribution, tumour targeting and pharmacokinetic analysis. METHODS: Four cohorts of three patients (9 with advanced prostate cancer, 2 with pancreatic and 1 with bladder cancer) were dosed with 1 mg, ~250 MBq of [67Ga]Ga-DOTA-Miltuximab®. Cohort 1 received [67Ga]Ga-DOTA-Miltuximab® alone, while cohorts 2-4 were pre-infused with increasing doses (3.5, 11.5 and 24 mg, respectively) of unlabelled Miltuximab®-DOTA 1 hour prior to [67Ga]Ga-DOTA-Miltuximab®. Safety and tolerability were assessed by clinical and standard laboratory assessments. Patients underwent whole body gamma-camera scans and SPECT/CT scans up to 144 h post-infusion. Total organ radiation exposure was determined by dosimetry of whole-body gamma scans. RESULTS: The dosing regimen was well tolerated, with no drug-related adverse events observed. Liver and spleen uptake of [67Ga]Ga-DOTA-Miltuximab® was observed. Liver uptake was reduced by pre-infusion of unlabelled Miltuximab®-DOTA. Dosimetry analysis showed a favorable exposure profile. [67Ga]Ga-DOTA-Miltuximab® targeting to tumour sites was observed in two prostate cancer patients who had failed enzalutamide treatment. Higher doses of unlabelled antibody achieved lower liver uptake and increased antibody serum half life. CONCLUSIONS: This study is the first in human for Miltuximab® a first in class antibody targeting GPC-1. The trial met its primary endpoint of safety, demonstrating its potential as a safe and tolerable monoclonal antibody. This safety data, together with targeting to tumour lesions and biodistribution information supports the further clinical development of Miltuximab® as a theranostic agent in a planned Phase I human trial.

Clinical trials best practice checklist: Guidance for Australian clinical research sites from CT:IQ.

The Australian clinical trials sector has grown steadily over the past decade, particularly with respect to early phase trials where Australia's research capacity, capability and quality of research is revered. With an increase in the number of internationally sponsored clinical research projects being conducted in Australia, particularly in the early phase setting, there has been a corresponding growth in the number of clinical research sites conducting early phase clinical trials. Australian researchers are guided by a multitude of research codes, guidance and statements which govern the conduct of clinical trials. Although international guidance regarding the conduct of early phase clinical trials exists, there is currently no single source outlining best practice recommendations for the conduct of early phase clinical trials in Australia. In recognition of this Clinical Trials: Impact & Quality (CT:IQ), a collaborative of sector stakeholders, convened a project team with comprehensive knowledge of the Australian clinical trials sector and particularly early phase research, to evaluate and collate broadly applicable and implementable guidance for the conduct of early phase clinical trials. Although the initial intent was to create guidance specific to early phase, we recognize the project outcomes are more broadly implementable irrespective of the research phase and are intended to support all clinical research sites to conduct high-quality clinical trials in Australia.

Real-world experience of the feasibility and tolerability of the 2/1 dosing schedule with sunitinib in the treatment of patients with advanced renal cell carcinoma in Australia.

AIM: Sunitinib is a first-line treatment option for metastatic renal cell carcinoma (mRCC) funded by the Australian Pharmaceutical Benefits Scheme. Toxicities are common with the standard schedule leading to alternative dosing schedules to be suggested. We reviewed Australian treatment practices to evaluate the safety and outcomes of patients on a 2 weeks on, 1 week off treatment schedule (2/1). METHODS: We performed a retrospective review of 63 patients with mRCC treated with first-line sunitinib on a 2/1 schedule at four Australian centers. RESULTS: Forty-six patients (73%) initiated sunitinib on the 2/1 schedule whereas 17 (27%) switched from the 4/2 schedule due to toxicity. Three progressing on a 4/2 schedule tolerated up-titration of their dose with a clinical and radiological response on the 2/1 schedule. The median duration of treatment was 31.9 months; median duration of treatment on the 2/1 schedule in patients changing from 4/2 was 11.5 months. Few (6.3%) ceased due to toxicity. Median overall survival was 37.2 months. CONCLUSION: In this retrospective review of the 2/1 sunitinib schedule, time on treatment with clinical benefit exceeded the overall survival times seen in the phase III trials utilizing the 4/2 schedule. Overall survival also exceeded that seen in these trials. Few patients ceased due to toxicity. The 2/1 schedule appears to be an acceptable schedule to use in selected patients with mRCC both at initiation of first-line treatment and in those intolerant to the 4/2 schedule.

Dose individualization of sunitinib in metastatic renal cell cancer: toxicity-adjusted dose or therapeutic drug monitoring.

PURPOSE: Dose individualization of sunitinib has been proposed using therapeutic drug monitoring (TDM) or toxicity-adjusted dose (TAD). We prospectively studied aspects of TDM and TAD to inform future trials, namely (1) intrapatient variability (CV) of sunitinib and (2) feasibility of a TAD protocol. METHODS: Sunitinib dose was adjusted to ensure grade 1 or 2 toxicity on 10-20 days of each 42-day cycle. Total trough levels (TTL) C min of sunitinib and its active metabolite were measured every 6 weeks. RESULTS: In 45 patients with mRCC, 283 TTL samples were assayed over a median 30 weeks (6-108 weeks). Fifteen patients (33%) had an intrapatient CV of >25% in TTL. Ninety-one percent achieved target toxicity with a final sunitinib dose of 25 mg (18%), 37.5 mg (27%), 50 mg (50%), and 62.5 or 75 mg (7%). TTL C min was <50, 50-100, and >100 ng/mL in 7 (15%), 31 (69%), and 7 patients (15.5%), respectively. The median overall survival was 32 months. CONCLUSIONS: Sunitinib level has minimal variability in the majority of patients on stable dose. A subset of patients had a significant intrapatient variation, so we recommend two samples 4 to 6 months apart. TAD is feasible for dosing sunitinib and showed a favourable outcome.

Use of Neoadjuvant Chemotherapy Plus Molecular Targeted Therapy in Colorectal Liver Metastases: A Systematic Review and Meta-analysis.

BACKGROUND: Surgery remains the standard of care for patients with colorectal liver metastases (CLMs), with a 5-year survival rate approaching 35%. Perioperative chemotherapy confers a survival benefit in selected patients with CLMs. The use of molecular targeted therapy combined with neoadjuvant chemotherapy for CLMs, however, remains controversial. We reviewed the published data on combination neoadjuvant chemotherapy and molecular targeted therapy for resectable and initially unresectable CLMs. MATERIALS AND METHODS: A literature search of the Medline and PubMed databases was conducted to identify studies of neoadjuvant chemotherapy plus molecular targeted therapy in the management of resectable or initially unresectable CLMs. We calculated the pooled proportion and 95% confidence intervals using a random effects model for the relationship of the combination neoadjuvant treatment on the overall response rate and performed a systematic review of all identified studies. The analysis was stratified according to the study design. RESULTS: The data from 11 studies of 908 patients who had undergone systemic chemotherapy plus targeted therapy for CLM were analyzed. The use of combination neoadjuvant therapy was associated with an overall response rate of 68% (95% confidence interval, 63%-73%), with significant heterogeneity observed in the studies (I2 = 89.35; P < .001). Of the 11 studies, 4 used a combination that included oxaliplatin, 2 included irinotecan, and 5 included a combination of both. Also, 7 studies used cetuximab and 4 bevacizumab. The overall progression-free survival was estimated at 14.4 months. CONCLUSION: Current evidence suggests that neoadjuvant chemotherapy plus molecular targeted agents for CLM confers high overall response rates. Combination treatment might also increase the resectability rates in initially unresectable CLM. Further studies are needed to examine the survival outcomes, with a focus on the differential role of molecular targeted therapy in the neoadjuvant versus adjuvant setting.

Patterns and trends in the incidence of paediatric and adult germ cell tumours in Australia, 1982-2011.

PURPOSE: Germ cell tumour (GCT) aetiology is uncertain and comprehensive epidemiological studies of GCT incidence are few. METHODS: Nationwide data on all malignant GCTs notified to Australian population-based cancer registries during 1982-2011 were obtained. Age- and sex-specific, and World age-standardised incidence rates were calculated for paediatric (0-14) and adult (15+) cases using the latest WHO subtype classification scheme. Temporal trends were examined using Joinpoint regression. RESULTS: There were 17,279 GCTs (552 paediatric, 16,727 adult). Age-specific incidence in males (all histologies combined) was bimodal, with peaks during infancy for most sites, and second, larger, peaks during young adulthood. Incidence of ovarian tumours peaked at age 15-19. Around half of paediatric tumours were extragonadal, whereas adult tumours were mostly gonadal. Yolk sac tumours and teratomas predominated in infants, whereas germinomas became more frequent towards adulthood. Increasing incidence trends for some adult gonadal tumours have stabilised; the trend for male extragonadal tumours is also declining. CONCLUSION: Broad similarities in the shape of age-specific incidence curves, particularly for gonadal, central nervous system, and mediastinal tumours provide epidemiological support for commonalities in aetiology among clinically disparate GCT subtypes. Differences in peak ages reflect underlying subtype-specific biological differences. Declining incidence trends for some adult gonadal tumours accords with the global transition in GCT incidence, and supports the possibility of a reduction in prevalence of shared aetiological exposures.