A transatlantic perspective on the integration of immuno-oncology prognostic and predictive biomarkers in innovative clinical trial design.

Immuno-therapeutics aim to activate the body's own immune system against cancer and are one of the most promising cancer treatment strategies, but currently limited by a variable response rate. Biomarkers may help to distinguish those patients most likely to respond to therapy; they may also help guide clinical decision making for combination therapies, dosing schedules, and determining progression versus relapse. However, there is a need to confirm such biomarkers in preferably prospective clinical trials before they can be used in practice. Accordingly, it is essential that clinical trials for immuno-therapeutics incorporate biomarkers. Here, focusing on the specific setting of immune therapies, we discuss both the scientific and logistical hurdles to identifying potential biomarkers and testing them in clinical trials.

Intracellular signalling via the AKT axis and downstream effectors is active and prognostically significant in cancer of unknown primary (CUP): a study of 100 CUP cases.

BACKGROUND: Hypothesising that cancer of unknown primary (CUP) may harbour unique characteristics, we present a translational study of the immunohistochemical expression and clinical correlation of key PTEN/AKT pathway molecules. PATIENTS AND METHODS: We collected 100 paraffin-embedded CUP tissue blocks. We studied using tissue microarrays the expression of PTEN, phospho-AKT, Cyclin D1, p21, phospho-RPS6. From the percentage of staining tumour cells and the literature, we selected cut-offs to classify the expression of each biomolecule. We correlated IHC expression with clinical data. RESULTS: PTEN, pAKT, and pRPS6 showed frequent expression. At univariate analysis, high IHC expression of pAKT and pRPS6 displayed statistically significant association with worse survival. Prognosis was worse upon concurrent high IHC expression of pMAPK and pAKT {median overall survival = 8 months [95% confidence interval (CI) 5.3-10.7] versus 17 months [95% CI 13.1-20.9]}. In multivariate analysis, high p21 was associated with better survival (risk ratio [RR] = 0.34 [95% CI 0.16-0.73], P = 0.005). High expression of pAKT (RR = 2.39 [95% CI 1.23-4.66], P = 0.01) or pRPS6 (RR = 2.76 [95% CI 1.31-5.84], P = 0.008) was associated with worse survival. CONCLUSIONS: p21 expression conferred favourable prognosis, while high pAKT or pRPS6 expression predicted worse prognosis. Concurrent MAPK and pAKT expression had a marked adverse impact on survival.

Serial FDG-PET/CT for early outcome prediction in patients with metastatic colorectal cancer undergoing chemotherapy.

BACKGROUND: The study purpose was to assess the predictive value of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computerized tomography (CT) metabolic response after a single course of chemotherapy in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: FDG-PET/CT scans were carried out at baseline and on day 14 in 41 patients with unresectable mCRC treated with a biweekly regimen of chemotherapy. Metabolic nonresponse was defined by <15% decrease in FDG uptake in the dominant proportion of the patient's lesions or if a lesion was found metabolically progressive. The PET-based response was correlated with radiological response (primary end point) and patient's outcome (secondary end points). RESULTS: RECIST response rate in metabolically responding patients was 43% (10 of 23) compared with 0% (0 of 17) in nonresponding patients (P=0.002). The metabolic assessment's predictive performance for RECIST response was sensitivity 100% [95% confidence interval (CI) 69% to 100%], specificity 57% (95% CI 37% to 75%), positive predictive value 43% (95% CI 23% to 66%), and negative predictive value 100% (95% CI 80% to 100%). Comparing metabolically responding versus nonresponding patients, the hazard ratio (HR) was 0.28 (95% CI 0.10-0.76) for overall survival and 0.57 (95% CI 0.27-1.21) for progression-free survival. CONCLUSION: The metabolic response measured by FDG-PET/CT after a single course of chemotherapy in mCRC is able to identify patients who will not benefit from the treatment.

Results of screening in early and advanced thoracic malignancies in the EORTC pan-European SPECTAlung platform.

Access to a comprehensive molecular alteration screening is patchy in Europe and quality of the molecular analysis varies. SPECTAlung was created in 2015 as a pan-European screening platform for patients with thoracic malignancies. Here we report the results of almost 4 years of prospective molecular screening of patients with thoracic malignancies, in terms of quality of the program and molecular alterations identified. Patients with thoracic malignancies at any stage of disease were recruited in SPECTAlung, from June 2015 to May 2019, in 7 different countries. Molecular tumour boards were organised monthly to discuss patients' molecular and clinical profile and possible biomarker-driven treatments, including clinical trial options. FFPE material was collected and analysed for 576 patients with diagnosis of pleural, lung, or thymic malignancies. Ultimately, 539 patients were eligible (93.6%) and 528 patients were assessable (91.7%). The turn-around time for report generation and molecular tumour board was 214 days (median). Targetable molecular alterations were observed in almost 20% of cases, but treatment adaptation was low (3% of patients). SPECTAlung showed the feasibility of a pan-European screening platform. One fifth of the patients had a targetable molecular alteration. Some operational issues were discovered and adapted to improve efficiency.

Targeting c-KIT, PDGFR in cancer of unknown primary: a screening study for molecular markers of benefit.

AIMS: In view of available targeted therapies, we investigated the presence of c-kit, PDGFR gene mutations and protein expression in cancer of unknown primary (CUP) in order to study their contribution in pathogenesis, their prognostic value and potential as therapeutic targets. METHODS: Mutations in hot spots c-kit exon 11 and PDGFR exons 12 and 18 were studied in paraffin-embedded tumour samples from 50 patients with CUP by means of PCR-based single-strand conformational polymorphism and protein expression by means of streptavidin-biotin immunoperoxidase assays. Molecular markers were screened for possible correlations with patient outcome. RESULTS: No shifted band was detected in any of the polyacrylamide gel electrophoreses, indicating absence of c-kit exon 11 and PDGFR exon 12, 18 mutations. Immunohistochemical analysis in 37 tumours revealed positive membranous CD117 expression in 30 samples (81%) of which five exhibited strong (+3), four moderate (+2) and 21 weak (+1) staining. PDGFRa protein staining was seen in 15 out of 30 (50%) cases, mostly weak (13) and rarely moderate (1) or strong (1). The expression of KIT or PDGFRa protein did not correlate with the clinical outcome of the patients in our cohort. CONCLUSIONS: In a moderate-sized CUP patient cohort, KIT or PDGFRa protein overexpression is rare, does not have gross prognostic significance for survival and is not associated with presence of activating mutations.

Systemic dissemination in cancer of unknown primary is independent of mutational inactivation of the KiSS-1 metastasis-suppressor gene.

Cancer of unknown primary represents a heterogeneous group of malignancies characterised by early systemic dissemination and lack of primary site. KiSS1 is a member of the metastasis-suppressor gene family whose functional role is being investigated in human malignancies. We extracted DNA from 50 paraffin-embedded unknown primary tumors and screened KiSS1 exons III and IV for presence of mutations by means of Single Strand Conformational Polymorphism and direct sequencing. Only one tumor specimen harboured a cytosine to guanine point substitution in base 242 of exon IVa, resulting in a proline to arginine switch at codon 81 of the KiSS1 protein (P81R). The remaining 49 tumors harbored wild-type KiSS1 alleles, indistinguishable from those of peripheral blood lymphocytes of 50 healthy controls. Consequently, the propensity for systemic spread of unknown primary tumors may by due to mutations in genes other than KiSS1 or aberrant epigenetic regulation.

Weekday on-weekend off oral capecitabine: a phase I study of a continuous schedule better simulating protracted fluoropyrimidine therapy.

BACKGROUND: Although protracted intravenous 5-fluorouracil is superior to bolus regimens in terms of tumour exposure to the drug during DNA synthesis as well as activity and safety, the oral fluoropyrimidine capecitabine is administered intermittently. In this phase I study, we investigated an alternative, dose-intense continuous regimen. MATERIALS AND METHODS: Oral capecitabine was administered twice daily continuously with weekend breaks, in patients with advanced solid tumours refractory to standard therapy. Dose escalation proceeded from 1,331 to 2,510 mg/m(2) daily. Dose limiting toxicity (DLT) consisted of any grade-3 or 4 adverse event except for alopecia and skin toxicity resolving within 7 days. RESULTS: Twenty-five heavily pretreated patients participated in the study. No DLT occurred in the first four cohorts. Two out of four patients developed grade III diarrhoea in the fourth week of capecitabine at 2,510 mg/m(2) (DLT). The most common toxic episodes during all cycles of treatment were grade 1-2 fatigue, skin erythema, abdominal cramps, nausea, constipation and neutropenia. Disease regression was seen in three and stabilisation with clinical benefit in ten patients (clinical benefit response 54%). Pharmacokinetic studies of capecitabine and metabolites in four patients at 2,250 mg/m(2 )daily showed rapid absorption, short plasma half-lives with the exception of FBAL and absence of accumulation or conversion saturation during the course of therapy. At this dose, administered dose intensity in eight patients was 99.3% of the planned one. CONCLUSIONS: Weekday on-weekend off capecitabine maximizes cytotoxic impact on tumour cells during S-phase by safely simulating protracted fluoropyrimidine therapy at a recommended dose (2,250 mg/m(2)) close to that of the intermittent schedule and clearly higher than the continuous one of 1,331 mg/m(2).