Significance: Regulatory T (Treg) cells, expressing CD25 and Foxp3, constitute about 5 to 10% of peripheral CD4⁺T cells and maintain immunological self-tolerance through the suppression of various immune responses. Here we found that skin Treg cells expanded by UVB exposure possess a unique TCR repertoire and a healing function. UVB-expanded skin Treg (UVB-skin Treg) cells expressed proenkephalin (PENK), an endogenous opioid precursor, and amphiregulin (AREG), the epidermal growth factor receptor ligand. The Treg-derived PENK and AREG promoted keratinocyte outgrowth in a skin explant assay. Moreover, UVB-expanded skin Treg cells played a key role in promoting wound healing in vivo. Our results provide a new implication in developing a therapy using PENK⁺UVB-skin Treg cells.

The present study aimed to clarify the incidence and clinical outcomes of nasopharyngeal carcinoma (NPC) in the Chubu region of Japan from 2006 to 2015, compared with previous reports. A retrospective analysis was conducted based on medical records from 40 hospitals located in the Chubu region in the central Japanese main island, with a population of around 22.66 million individuals. This study was designed in line with to two previous clinical studies into NPC conducted in the same area of Japan. We recruited NPC patients diagnosed in hospitals across this area over a 10-year period (2006–2015) using a questionnaire about sex, age, primary site, clinical symptoms, pathology, Union for International Cancer Control (UICC) staging, serological exam, treatment, and survival. A total of 620 NPC patients were identified. The age-standardized incidence of NPC from 2006 to 2015 was 0.27 per 100,000 individuals per year. There were no significant differences between this study and the previous two studies conducted in the same area of Japan. The five-year overall survival rate for all patients was 75.9%, while those for patients with stages I, II, III, and IVA were 97%, 91%, 79%, and 68%, respectively. The age-standardized annual incidence of NPC in the present study was 0.27 per 100,000 individuals per year, which was relatively low and stable. The five-year overall survival rate for all NPC patients was significantly improved in this decade compared with previous studies. The smoking rates in male and female NPC patients were 64.5% and 18.8%, respectively, thereby suggesting the involvement of smoking in the incidence of NPC.

Induction chemotherapy for patients with head and neck cancer is widely performed, and several advantages of induction chemotherapy have been reported. However, there is currently insufficient evidence to strongly recommend induction chemotherapy. In this study, we analyzed the outcomes for patients treated with induction chemotherapy and subsequent definitive treatments. Operable patients with untreated oropharyngeal, hypopharyngeal and laryngeal squamous cell carcinoma treated with induction chemotherapy were included in this retrospective study. We conducted induction chemotherapy using docetaxel, cisplatin and 5-fluorouracil and performed subsequent surgical treatment or radiotherapy according to the response to induction chemotherapy. A total of 65 patients were included in this study, and 50 patients (76.9%) had Stage IV tumors. The response to induction chemotherapy was CR in two patients, PR in 55 patients, and SD in eight patients. The subsequent definitive treatment was radiotherapy in 60 patients, and surgery in five patients. The 3-year overall survival rates for patients who received radiotherapy and surgery were 88.4% and 75.0%, respectively (P = 0.30). The 3-year disease-free survival rates for patients who received radiotherapy and surgery were 68.0% and 0%, respectively (P = 0.01). The 3-year laryngeal dysfunction free survival rates for patients who received RT and surgery were 77.8% and 0%, respectively (P < 0.01). We achieved favorable survival outcomes and high larynx preservation rates. Our results suggest that induction chemotherapy using TPF regimen is one of the optimal treatment strategies when treating head and neck cancers. Further prospective studies with a larger cohort are required to confirm our findings.

Background: In recent years, particle therapy has shown promise as a local treatment for salivary gland carcinoma (SGC); however, its efficacy and safety remain unclear. This study aimed to evaluate the clinical outcomes of intensity‐modulated proton therapy (IMPT) for SGC.Methods: We performed a single‐institution retrospective analysis of patients with SGC who underwent IMPT.Results: IMPT was performed on 28 SGC patients, of which 18 were for definitive treatment and 10 were for postoperative treatment. The 2‐year overall survival (OS), progression‐free survival (PFS), and local control (LC) rates for definitive treatment cases were 70.1%, 25.0%, and 82.5%, respectively. The 2‐year OS, PFS, and LC rates for postoperative treatment cases were 100%, 80.0%, and 90.0%, respectively. Quality of life scores in the EORTC QLQ‐C30 and QLQ‐HN35 were preserved for 1 year after treatment.Conclusions: Our study suggests the efficacy and safety of IMPT in SGC patients.

Background: The NTRK fusion gene is detected in most salivary gland secretory carcinomas. While tropomyosin receptor kinase (TRK) inhibitors are used for various solid tumors with the fusion gene, there are no reports regarding TRK inhibitor use for unresectable parotid gland carcinomas that subsequently shrink and become resectable. Here, we report a case of salivary gland secretory carcinoma in which conversion surgery was performed after TRK inhibitor use. Methods: The patient was a 33‐year‐old man with a left parotid gland tumor. Examinations revealed a tumor invading the poststyloid compartment and ETV6 ‐ NTRK3 fusion gene expression. Results: Entrectinib administration shrunk the tumor to a size surgically resectable with an adequate margin. The patient underwent total parotidectomy with left supraomohyoid neck dissection. Conclusions: Conversion surgery and TRK inhibitor use were effective against unresectable parotid gland carcinoma with the NTRK fusion gene. The case provides a reference for conversion surgery use for unresectable parotid gland carcinomas.