[Ⅰ seed brachytherapy for recurrent salivary gland carcinoma after external radiotherapy].

OBJECTIVE

To investigate the clinical application and efficacy of Ⅰ radioactive seeds implantation in the treatment of recurrent salivary gland carcinoma after external radiotherapy.

METHODS

From July 2004 to July 2016, 43 cases of recurrent salivary gland carcinoma of the neck after external radiotherapy or surgery combined with external radiotherapy were treated. According to the conventional segmentation radiotherapy for head and neck cancer (once a day, 1.8-2.0 Gy each time, 5 days per week), the cumulative radiation dose of the patients in this group was calculated. In the study, 26 patients received 50-60 Gy, 7 patients received less than 50 Gy, 4 patients received 60-70 Gy, and 6 patients received more than 80 Gy (range: 80-120 Gy). The interval between the last external irradiation and local recurrence was 4-204 months, and the median interval was 48 months. Among them, 25 cases were treated with Ⅰ radioactive seeds implantation only and 18 cases were treated with Ⅰ radioactive seeds implantation after operation. The prescription dose was 100-140 Gy. The control rate, survival rate and disease-free survival rate were recorded to evaluate the side effects.

RESULTS

The median follow-up time was 27 months (ranging from 2.5 to 149.0 months). Among them, the median follow-up time of adenoid cystic carcinoma patients was 31 months (range: 2.5-112.0 months), and the median follow-up time of mucoepidermoid carcinoma patients was 18 months (range: 5-149 months). The local control rates for 1, 3 and 5 years were 66.5%, 48.8% and 42.7%, respectively. The 1-, 3- and 5- year survival rates were 88.0%, 56.7% and 45.8%, respectively. The disease-free survival rates of 1, 3 and 5 years were 58.3%, 45.4% and 38.1%, respectively. There was no statistically significant difference in local control rate, survival rate, and disease-free survival between the radioactive seeds implantation group and the radioactive seeds implantation group after surgical resection. There were 2 cases of acute radiation reaction Ⅰ/Ⅱ and 3 cases of reaction Ⅲ or above. In the late stage of radiotherapy, there were 8 cases with Ⅰ/Ⅱ grade reaction and 3 cases with Ⅲ grade or above reaction. The incidence of radiation reactions of Grade Ⅲ and above was 7%.

CONCLUSION

Ⅰ radioactive seeds implantation provides an alternative method for the treatment of recurrent salivary gland carcinoma after external radiotherapy. The local control rate and survival rate are improved on the premise of low incidence of side effects.