Session Item

The recommended treatments for basal cell carcinoma (BCC) in the head and neck (H&N) region are Mohs surgery, standard surgical excision, and radiotherapy. According to the available literature, the local recurrence after primary surgical treatment in this area is associated with a worse prognosis in the case of re-treatment. To our knowledge, there are no scientific reports on the results of treating only the BCC of the H&N region by high-dose brachytherapy (HDR-BT), both in the case of primary lesions and relapses after previous standard surgical excision. The aim of this study is to fill this gap in the literature.

Between 03.2012 and 02.2017 a total number of 510 patients with diagnosed skin neoplasms were treated with different techniques, dose rates, and schedules of BT. The clinical inclusion criteria for this study were pathologically confirmed BCC, tumor location in the H&N region, treatment performed with superficial HDR-BT in 2D planning using the 10 x 5 Gy fractionation scheme, and a minimum follow-up of 12 months from the end of treatment. A retrospective analysis was performed on a group of 90 patients in whom a total of 102 tumors were treated. Subsequently, tumors were divided into two subgroups - those treated initially with HDR-BT and treated with this method due to local recurrence after previous standard surgical excision. The primary treatment group included 59 tumors (47 T1 and 12 T2). Whereas 43 tumors were included in the recurrent group (35 T1 and 8 T2). Early skin toxicity was assessed 4 weeks after the treatment, then every 3-6 months the late toxicity was evaluated (using the RTOG scale).

Statistical analysis didn’t reveal any significant differences between the groups in terms of age (both medians 72.9 y, p=0.43), duration of treatment (both medians 11 d, p=0.17), follow-up time (median 41.4 m vs. 43.5 m, p=0.96), sex (p=0.18), local advancement (p=0.83) and location (p=0.68). The Kaplan-Meier-estimated 5-year relapse-free survival was 96.4% in the primary group and 94.6% in the recurrent group. Using the log-rank test, no statistically significant difference was found in the number of recurrences in both groups (p=0.72). In the primary group toxicity presented as follows: early G1-20.3%, G2-28.8%, G3-42.4%, G4-8.5%; late G1-33.9%, G2-50.8%, G3-1.7%, G4-11.9%. Whereas, in the recurrent group toxicity presented as follows: early G1-16.3%, G2-41.9%, G3-37.2%, G4-4.6%; late G1-30.2%, G2-62.8%, G3 - 4.6%. There were no statistically significant differences in the early nor late toxicity between the groups (p=0.54 and p=0.16). The analysis of factors influencing the increased toxicity showed higher degrees of late complications after the treatment of T2 tumors (p=0.028).

Superficial 2D HDR-BT in the presented fractionation scheme is a highly effective treatment method for both primary and recurrent BCC after standard surgical excision of the H&N region and is associated with acceptable early and late skin toxicity.