A randomised controlled trial of long NY-ESO-1 peptide-pulsed autologous dendritic cells with or without alpha-galactosylceramide in high-risk melanoma.

AIM: We have previously reported that polyfunctional T cell responses can be induced to the cancer testis antigen NY-ESO-1 in melanoma patients injected with mature autologous monocyte-derived dendritic cells (DCs) loaded with long NY-ESO-1-derived peptides together with α-galactosylceramide (α-GalCer), an agonist for type 1 Natural Killer T (NKT) cells. OBJECTIVE: To assess whether inclusion of α-GalCer in autologous NY-ESO-1 long peptide-pulsed DC vaccines (DCV + α-GalCer) improves T cell responses when compared to peptide-pulsed DC vaccines without α-GalCer (DCV). DESIGN, SETTING AND PARTICIPANTS: Single-centre blinded randomised controlled trial in patients ≥ 18 years old with histologically confirmed, fully resected stage II-IV malignant cutaneous melanoma, conducted between July 2015 and June 2018 at the Wellington Blood and Cancer Centre of the Capital and Coast District Health Board. INTERVENTIONS: Stage I. Patients were randomised to two cycles of DCV or DCV + α-GalCer (intravenous dose of 10 × 106 cells, interval of 28 days). Stage II. Patients assigned to DCV + α-GalCer were randomised to two further cycles of DCV + α-GalCer or observation, while patients initially assigned to DCV crossed over to two cycles of DCV + α-GalCer. OUTCOME MEASURES: Primary: Area under the curve (AUC) of mean NY-ESO-1-specific T cell count detected by ex vivo IFN-γ ELISpot in pre- and post-treatment blood samples, compared between treatment arms at Stage I. Secondary: Proportion of responders in each arm at Stage I; NKT cell count in each arm at Stage I; serum cytokine levels at Stage I; adverse events Stage I; T cell count for DCV + α-GalCer versus observation at Stage II, T cell count before versus after cross-over. RESULTS: Thirty-eight patients gave written informed consent; 5 were excluded before randomisation due to progressive disease or incomplete leukapheresis, 17 were assigned to DCV, and 16 to DCV + α-GalCer. The vaccines were well tolerated and associated with increases in mean total T cell count, predominantly CD4+ T cells, but the difference between the treatment arms was not statistically significant (difference - 6.85, 95% confidence interval, - 21.65 to 7.92; P = 0.36). No significant improvements in T cell response were associated with DCV + α-GalCer with increased dosing, or in the cross-over. However, the NKT cell response to α-GalCer-loaded vaccines was limited compared to previous studies, with mean circulating NKT cell levels not significantly increased in the DCV + α-GalCer arm and no significant differences in cytokine response between the treatment arms. CONCLUSIONS: A high population coverage of NY-ESO-1-specific T cell responses was achieved with a good safety profile, but we failed to demonstrate that loading with α-GalCer provided an additional advantage to the T cell response with this cellular vaccine design. CLINICAL TRIAL REGISTRATION: ACTRN12612001101875. Funded by the Health Research Council of New Zealand.

The New Zealand PIPER Project: colorectal cancer survival according to rurality, ethnicity and socioeconomic deprivation-results from a retrospective cohort study.

AIM: To investigate differences in survival after diagnosis with colorectal cancer (CRC) by rurality, ethnicity and deprivation. METHODS: In this retrospective cohort study, clinical records and National Collections data were merged for all patients diagnosed with CRC in New Zealand in 2007-2008. Prioritised ethnicity was classified using New Zealand Cancer Registry data; meshblock of residence at diagnosis was used to determine rurality and socioeconomic deprivation. RESULTS: Of the 4,950 patients included, 1,938 had died of CRC by May 2014. The five-year risks of death from CRC were: Maori 47%; Pacific 59%; non-Maori-non-Pacific (nMnP) 38%. After adjustment for demographic characteristics, comorbidity and disease stage at diagnosis, compared to nMnP the relative risk (RR) for Maori was 1.1 (95%CI: 0.8-1.3) and for Pacific 1.8 (95% CI: 1.4-2.5). We found no differences in risk of death from CRC by rurality, but some differences by deprivation. CONCLUSIONS: Disparity in outcome following diagnosis with CRC exists in New Zealand. Much of this disparity can be explained by stage of disease at diagnosis for Maori, but for Pacific peoples and those in deprived areas other factors may influence outcome. Further analyses of the PIPER data will explore the impact of any differences in management.

A phase I vaccination study with dendritic cells loaded with NY-ESO-1 and α-galactosylceramide: induction of polyfunctional T cells in high-risk melanoma patients.

Vaccines that elicit targeted tumor antigen-specific T-cell responses have the potential to be used as adjuvant therapy in patients with high risk of relapse. However, the responses induced by vaccines in cancer patients have generally been disappointing. To improve vaccine function, we investigated the possibility of exploiting the immunostimulatory capacity of type 1 Natural killer T (NKT) cells, a cell type enriched in lymphoid tissues that can trigger improved antigen-presenting function in dendritic cells (DCs). In this phase I dose escalation study, we treated eight patients with high-risk surgically resected stage II-IV melanoma with intravenous autologous monocyte-derived DCs loaded with the NKT cell agonist α-GalCer and peptides derived from the cancer testis antigen NY-ESO-1. Two synthetic long peptides spanning defined immunogenic regions of the NY-ESO-1 sequence were used. This therapy proved to be safe and immunologically effective, inducing increases in circulating NY-ESO-1-specific T cells that could be detected directly ex vivo in seven out of eight patients. These responses were achieved using as few as 5 × 105 peptide-loaded cells per dose. Analysis after in vitro restimulation showed increases in polyfunctional CD4+ and CD8+ T cells that were capable of manufacturing two or more cytokines simultaneously. Evidence of NKT cell proliferation and/or NKT cell-associated cytokine secretion was seen in most patients. In light of these strong responses, the concept of including NKT cell agonists in vaccine design requires further investigation.

Transient elevation in serum carcinoembryonic antigen while on adjuvant chemotherapy for colon cancer: Is this of prognostic importance?

AIMS: Serum carcinoembryonic antigen (CEA) is used to detect relapses from colon cancer following initial surgical or adjuvant treatment. There are little data on transient elevations of CEA while receiving chemotherapy in the adjuvant setting. We aimed to review patterns of change in CEA levels while receiving adjuvant chemotherapy and investigate associations between transient rises and patient survival. METHODS: A retrospective review of patients in Auckland with a new diagnosis of colon cancer in 2001 or 2005 was performed and CEA values were collected. Three patient groups were defined: no increase in CEA; transient elevation in CEA; and persistent elevation in CEA. Kaplan-Meier methods were used to estimate 5-year survival; Cox regression and log-rank P-values were used to compare survival. RESULTS: Sixty-one patients with stage II or III disease who had received adjuvant chemotherapy had sufficient CEA data to be included in the analysis. Patients were followed up for a minimum of 7.4 years (or death). The 5-year overall survival was higher in the transient elevation in CEA group 95.0% and the no increase in CEA group 85.2% compared with the persistent elevation in CEA group 42.9%. There was no statistically significant difference in overall survival between the transient elevation group and the no increase group (P = 0.2). CONCLUSIONS: The group with a transient elevation in CEA during adjuvant chemotherapy did not have a poorer prognosis compared with the group that had no increase in CEA. This will be further examined in a population-based New Zealand-wide study of colorectal cancer diagnosis, treatment and outcome.

Methods of a national colorectal cancer cohort study: the PIPER Project.

AIM: Colorectal cancer is one of the most common cancers, and second-leading cause of cancer-related death, in New Zealand. The PIPER (Presentations, Investigations, Pathways, Evaluation, Rx [treatment]) project was undertaken to compare presentation, investigations, management and outcomes by rurality, ethnicity and deprivation. This paper reports the methods of the project, a comparison of PIPER patient diagnoses to the New Zealand Cancer Registry (NZCR) data, and the characteristics of the PIPER cohort. METHOD: National, retrospective cohort review of secondary care medical records (public and private) of all cases of ICD-10-AM C18-C20 on the NZCR in the calendar years 2007 and 2008 (main cohort) and an extended sample of Maori and Pacific cases, and non-Maori non-Pacific controls in 2006 and 2009 (extended cohort). RESULTS: Of the 6,387 patients identified from the NZCR 5,610 (88%) were eligible for PIPER. Reasons for exclusion were non-adenocarcinoma histology (3%) and non-colorectal primary (2%). Data were collected on 3,695 patients with colon cancer, 1,385 with rectal cancer and 466 with cancer of the recto sigmoid junction. CONCLUSIONS: The PIPER Project has generated comprehensive population level data detailing the diagnosis and management of colorectal adenocarcinoma in New Zealand. This will be used to assess the care provided to patients, and the impact of variations in care occurring between patient groups.