Novel patterns of response under immunotherapy.

Novel patterns of response and progression to immunotherapy have been reported that are not observed with conventional cytotoxic or targeted anticancer treatments. A major breakthrough with immunotherapy is its potential to achieve durable responses in a subset of patients with advanced cancer that can be maintained several years even after stopping the treatment. No standardized definition of durable response exists in the literature, and the optimal duration of treatment in case of durable response is not clearly established. However, the majority of patients do not respond to immunotherapy. Initially reported in advanced melanoma patients, pseudoprogression occurs when tumor index lesions regress after initial progression, supporting the concept of treating some patients beyond progression. Overall, reported rates of pseudoprogression never exceeded 10%, meaning that the large majority of patients who have a disease progression will not eventually respond to treatment. The decision to pursue treatment beyond progression must therefore only be taken in carefully selected patients with clinical benefit, who did not experience severe toxicities with immunotherapy. Conversely, rapid progressions, called hyperprogressions, were reported by several teams with rates ranging from 4% to 29%. These observations need to be confirmed from randomized trials. It is essential to interrupt the treatment in patients with hyperprogression, in order to switch to another potentially active treatment. Finally, some patients experience dissociated responses, with some lesions shrinking and others growing. Local treatment with surgery or radiotherapy for growing lesions may be considered. Several immune-specific-related response criteria were developed to better capture benefits of immunotherapy. These criteria only address the pseudoprogression pattern of response, and do not capture the other patterns of response such as hyperprogression and dissociated response. The classic RECIST remains a reasonable and meaningful method to assess response to immunotherapy in the clinic.

Prognostic value of tumor mutational burden in patients with oral cavity squamous cell carcinoma treated with upfront surgery.

BACKGROUND: Oral cavity is the most prevalent site of head and neck squamous cell carcinomas (HNSCCs). Most often diagnosed at a locally advanced stage, treatment is multimodal with surgery as the cornerstone. The aim of this study was to explore the molecular landscape of a homogenous cohort of oral cavity squamous cell carcinomas (OCSCCs), and to assess the prognostic value of tumor mutational burden (TMB), along with classical molecular and clinical parameters. PATIENTS AND METHODS: One hundred and fifty-one consecutive patients with OCSCC treated with upfront surgery at the Institut Curie were analyzed. Sequencing of tumor DNA from frozen specimens was carried out using an in-house targeted next-generation sequencing panel (571 genes). The impact of molecular alterations and TMB on disease-free survival (DFS) and overall survival (OS) was evaluated in univariate and multivariate analyses. RESULTS: Pathological tumor stage, extranodal spread, vascular emboli, and perineural invasion were associated with both DFS and OS. TP53 was the most mutated gene (71%). Other frequent molecular alterations included the TERT promoter (50%), CDKN2A (25%), FAT1 (17%), PIK3CA (14%), and NOTCH1 (15%) genes. Transforming growth factor-ß pathway alterations (4%) were associated with poor OS (P = 0.01) and DFS (P = 0.02) in univariate and multivariate analyses. High TMB was associated with prolonged OS (P = 0.01 and P = 0.02, in the highest 10% and 20% TMB values, respectively), but not with DFS. Correlation of TMB with OS remained significant in multivariate analysis (P = 0.01 and P = 0.005 in the highest 10% and 20% TMB values, respectively). Pathological tumor stage combined with high TMB was associated with good prognosis. CONCLUSION: Our results suggest that a high TMB is associated with a favorable prognosis in patients with OCSCC treated with upfront surgery.

Combining immunotherapy with an epidrug in squamous cell carcinomas of different locations: rationale and design of the PEVO basket trial.

Squamous cell carcinomas (SCCs) are among the most frequent solid tumors in humans. SCCs, related or not to the human papillomavirus, share common molecular features. Immunotherapies, and specifically immune checkpoint inhibitors, have been shown to improve overall survival in multiple cancer types, including SCCs. However, only a minority of patients experience a durable response with immunotherapy. Epigenetic modulation plays a major role in escaping tumor immunosurveillance and confers resistance to immune checkpoint inhibitors. Preclinical evidence suggests that modulating the epigenome might improve the efficacy of immunotherapy. We herein review the preclinical and the clinical rationale for combining immunotherapy with an epidrug, and detail the design of PEVOsq, a basket clinical trial combining pembrolizumab with vorinostat, a histone deacetylase inhibitor, in patients with SCCs of different locations. Sequential blood and tumor sampling will be collected in order to identify predictive and pharmacodynamics biomarkers of efficacy of the combination. We also present how clinical and biological data will be managed with the aim to enable the development of a prospective integrative platform to allow secure and controlled access to the project data as well as further exploitations.

Efficacy of molecularly targeted agents given in the randomised trial SHIVA01 according to the ESMO Scale for Clinical Actionability of molecular Targets.

BACKGROUND: A randomised trial SHIVA01 compared the efficacy of matched molecularly targeted therapy outside their indications based on a prespecified treatment algorithm versus conventional chemotherapy in patients with metastatic solid tumours who had failed standard of care. No statistical difference was reported between the two groups in terms of progression-free survival (PFS), challenging treatment algorithm. The European Society for Medical Oncology (ESMO) Scale for Clinical Actionability of molecular Targets (ESCAT) recently defined criteria to prioritise molecular alterations (MAs) to select anticancer drugs. We aimed to retrospectively evaluate the efficacy of matched molecularly targeted agents (MTAs) given in SHIVA01 according to ESCAT tiers. PATIENTS AND METHODS: MAs used in SHIVA01 were retrospectively classified into ESCAT tiers, and PFS and overall survival (OS) were compared using log-rank tests. RESULTS: One hundred fifty-three patients were treated with matched MTAs in SHIVA01. MAs used to allocate MTAs were classified into tiers II, IIIA, IIIB and IVA according to the ESCAT. Median PFS was 2.0 months in tier II, 3.1 in tier IIIA, 1.7 in tier IIIB and 3.2 in tier IVA (p = 0.13). Median OS in tier IIIB was worse than that in tiers II, IIIA and IVA (6.3 months versus 11.7, 11.2 and 12.1, p = 0.002). CONCLUSIONS: Most MAs used to allocate therapy in SHIVA01 were shown to improve outcomes in other tumour types (tier IIIA). Worst outcome was observed in patients treated based on another type of alteration than the one reported to improve outcomes (tier IIIB), highlighting the crucial impact of the type of the alterations beyond the gene and the signalling pathway.