The feasibility of individualized primary CTV for lateralized nasopharyngeal carcinoma / 中华放射肿瘤学杂志

Objective:To investigate the feasibility of individualized primary clinical target volume (CTV) delineation in intensity-modulated radiotherapy for nasopharyngeal carcinoma (NPC).Methods:Clinical data of 87 consecutive patients newly diagnosed with lateralized NPC in Jiangsu Cancer Hospital between October 2016 and February 2018 were retrospectively analyzed. Lateralized NPC is defined as tumor invasion not exceeding the contralateral wall. According to the tumor spread, the primary CTV was optimized as follows: CTV2 only covered the medial part of the contralateral pterygopalatine fossa, whereas the contralateral foramen oval was not included; on the level of parapharyngeal space, the contralateral side of CTV only covered the posterior lateral lymph nodes, whereas the contralateral internal jugular vein was not regularly covered. Failure patterns and 5-year survival [local control rate (LCR), progression-free survival (PFS) and overall survival (OS)] were evaluated by Kaplan-Meier method. Paired t-test and rank-sum test were used to analyze the dose variation in the optimized region and adverse reactions. Results:The median follow-up time was 59.5 months. The 5-year LCR, PFS, and OS were 98.9%, 86.5% and 92.1%, respectively. There was no local recurrence in the optimized area of CTV. Dosimetric comparison results showed that the doses of parotid gland, temporal lobe, cochlea and middle ear on the contralateral side were reduced by 13.45%, 9.14%, 38.83%, and 29.36%, respectively. Four cases (4.6%) developed grade 3 hearing loss, all on the ipsilateral side. The optimized scheme significantly alleviated the hearing loss on the contralateral side compared to that on the ipsilateral side ( P<0.001). Other grade 3 late adverse reactions included cranial nerve injury, subcutaneous fibrosis in the neck and visual impairment, with 1 case each. Conclusion:Individualized primary CTV for lateralized NPC is feasible and safe, with obvious dosimetric advantages and reduced adverse reaction rate, which is worthy of clinical promotion.

Optimizing the target volume to boost the efficacy of radiation-induced immunomodulatory effects / 中华放射肿瘤学杂志

Radiotherapy is a pivotal method in cancer treatment harbouring immunomodulatory effects. Radiotherapy combined with immunotherapy has been proven to yield promising preliminary results in certain types of tumors. Most studies have concentrated on the dose fractionation of radiotherapy and timing of radiotherapy and immunotherapy. With the development of related studies, attention has been gradually paid to the influence of target volume upon circulating lymphocytes and tumor microenvironment. The interaction between target volume and immunotherapy has been valued. For tumors not suitable for hypofractionated radiotherapy, such as advanced esophageal cancer, conventional fractionated radiotherapy has been adopted. The volume and planning of target volume play a pivotal role in radiotherapy combined with immunotherapy. This article illustrates the feasibility of radiotherapy combined with immunotherapy, theory and conception of optimizing target volume.