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Photodynamic therapy (PDT) has shown promise in the treatment of a range of solid cancerous tumors. The study by Rigual and colleagues is the first to use 3-(1′-hexyloxyethyl) pyropheophorbide-a (HPPH) PDT for the treatment of squamous cell carcinoma of the oral cavity. PDT-induced signal transducer and activator of transcription 3 (STAT3) cross-linking was measured as a molecular marker for the evaluation of PDT mediated photoreaction. The HPPH-PDT was found safe, while sparing healthy vital and functional structures. The level of STAT3 cross-linking is a significant reporter for evaluating the PDT mediated photoreaction, and has the potential of serving as a prognostic biomarker for evaluating tumor response.Current chemoradiotherapy is effective only for proliferating cancer cells, while having little effect on quiescent cancer stem-like (CS-like) cells. Using a fluorescent ubiquitination cell-cycle indicator (FUCCI), Yano and colleagues demonstrated that oncolytic adenovirus OBP-301 decoys chemoresistant quiescent CS-like cells to cycle and lethally traps them in S-phase. Viability loss of the CS-like cells in the S/G2/M-phase trap was enhanced by chemotherapy, which was initiated at the time of fluorescence indication of entry into S/G2/M-phase. Oncolytic virus treatment and fluorescence indication for the time of chemotherapy initiation are thus a powerful approach to target chemoresistant quiescent CS-like cells.Recently, several studies have reported that FDG-PET-based response assessment may be more predictive than conventional CT-based response assessment after chemotherapy for follicular lymphoma. However, the question has remained whether these individual studies provide enough evidence to incorporate FDG-PET into routine practice. To generate a more evidence-based systematic summary for this issue, Pyo and colleagues conducted a meta-analysis of eight studies, which revealed consistent evidence that FDG-PET is more predictive of progression-free survival after chemotherapy and more efficient in distinguishing complete remission from residual disease than CT. These results favor adopting FDG-PET in the response evaluation of follicular lymphoma.Despite radical surgery and various regimens of chemoradiotherapy (CRT), survival rates remain lower than 50% for head and neck squamous cell cancer (HNSCC). The patients initially responsive to therapy develop recurrent disease, second primaries, or metastases. Mechanisms responsible for HNSCC patients' resistance to CRT remain unclear but may be in part related to CRT effects on the host immune system. Schuler and colleagues show that CRT increases the frequency of highly suppressive regulatory T cells (Treg) in the patients' circulation. The expanded Treg are resistant to activation-induced cell death, increase expression of prosurvival proteins BcL-2/BcL-xL, and are not affected by cisplatin. The persistence of Treg in the patients' circulation could be responsible for post-therapeutic immunosuppression leading to cancer recurrence in HNSCC patients.