Chemotherapy to potentiate the radiation-induced immune response.

Chemoradiation (CRT) is a conventional therapy used in local cancers, especially when they are locally advanced. Studies have shown that CRT induces strong anti-tumor responses involving several immune effects in pre-clinical models and humans. In this review, we have described the various immune effects involved in CRT efficacy. Indeed, effects such as immunological cell death, activation and maturation of antigen-presenting cells, and activation of an adaptive anti-tumor immune response are attributed to CRT. As often described in other therapies, various immunosuppressive mechanisms mediated, in particular, by Treg and myeloid populations may reduce the CRT efficacy. We have therefore discussed the relevance of combining CRT with other therapies to potentiate the CRT-induced anti-tumor effects.

Response to Chemoimmunotherapy Is Associated With Expansion of Systemic Antitumor CD4 + Th1 Response in Metastatic Non-Small Cell Lung Cancer.

Limited data have reported the evolution of antitumor immune responses under chemoimmunotherapy (chemo-IO) in patients with metastatic non-small cell lung cancer. In this concise study, we performed dynamic monitoring of antitumor CD4 + T helper 1 (Th1) response in peripheral blood from 12 patients receiving a first-line chemo-IO. Tumor-reactive CD4 + Th1 cells were assessed within blood lymphocytes using interferon-gamma enzyme-linked immunospot assay to detect telomerase (TERT)-specific T cells at baseline, 3 and 12 months after treatment. An induction of circulating anti-TERT CD4 + Th1 response were found in 6 of 12 patients at 3 months after chemo-IO. In contrast, 3 patients had a substantial decrease in their preexisting response and 3 remained nonimmune responders. Among patients with chemo-IO-induced immune response, half achieved an objective clinical response and had long-lasting circulating anti-TERT CD4 + Th1 cells detected for at least 1 year. In contrast, no objective response was documented in nonimmune responders and a link between the loss of anti-TERT CD4 + Th1 responses were observed in patients with progressive disease. This preliminary work supports a relationship between the efficacy of combinatorial chemo-IO and circulating anti-TERT CD4 + Th1 responses and highlights the interest to implement blood-based monitoring of tumor-reactive CD4 + T cells that could be additional help for patient management.

[Radiologic response assessment in metastatic colorectal cancers]. / Mesure de la réponse radiologique scannographique des cancers colorectaux métastatiques : état des lieux et perspectives.

The increasing indications of cytostatic biotherapies and the improvement in metastatic surgery have profoundly changed the management of metastatic colorectal cancer (mCRC) patients. Then the development of prognostic and predictive scores would be useful to stratify the treatments. Tumor radiological measurement is crucial to estimate treatment efficacy, and to predict pathological response and survival, and this parameter is included when a prognostic score is developed. But the standard size-based radiologic criteria, the Response Evaluation Criteria in Solid Tumors (RECIST), was designed ten years ago to assess tumor volume reduction after cytotoxic chemotherapy only. Nowadays, this method may be insufficient for mCRC patients. The aim of this review is to describe the different radiological assessments evaluated in mCRC, and to underline their correlations with patient's survival and pathologic response. A better knowledge of these radiological measurements would help to better integrate them in prospective trials, and in the prognostic and predictive scores. The choice of radiological measurement could be discussed regarding patient's situation, combining different approaches, and assessing tumoral mass quantification.