Abstract
Background : To assess the efficacy and prognosis of computed
tomography (CT)-guided 125I radioactive seeds
implantation brachytherapy (RSI-BT) for recurrent nasopharyngeal
carcinoma (NPC) after external beam radiotherapy (EBRT).
Methods : Thirty-one
patients with recurrent NPC (forty-one lesions) after EBRT from February
2003 to January 2019 were enrolled in this retrospective study. The
work-follow of CT-guidance RSI-BT was: indication selection, patient
set-up and immobilization on CT couch, CT-simulation, preoperative
planning, prescription doses (PD) definition of 110-160Gy, seed
implantation, postoperative dosimetric evaluation and postoperative
follow-up. Median radioactivity of RSI was 0.43 (range 0.22-0.79,
average 0.61) mCi. Median actuarial number of 125I
seeds was 24 (range 3-83, average 37). Median value of post-operative
D90 was 118.5 (range 62.4-246, average 136.2) Gy. Local control (LC) and
overall survival (OS) were investigated for their relationship with the
prognosis. The adverse events were evaluated by the Radiation Therapy
Oncology Group (RTOG) classification criteria.
Results : Median follow-up was 41.9 (range 2.1-60.2, average
44.1) months. Median LC was 35.8 (range 2.1-60.2, average 34.9) months.
LC at 1-, 3- and 5-year was 71.3%, 41.9% and 27.9%, respectively.
Median OS was 22.6 (range 2.1~60.2, average 27.1)
months. OS at 1-, 3- and 5-years was 57.7%, 23.8% and 11.9%,
respectively. Univariate analysis suggested that sex (P=0.037) and
frequency of previous EBRT (P=0.001) were prognostic factors influencing
LC. Moreover, univariate analysis also suggested that frequency of
previous EBRT (P=0.012) was prognostic factors influencing OS.
Prevalence of side effects (≥grade 3) was 6.5%.
Conclusion : 125I RSI-BT was a safe and
feasible salvage treatment for recurrent NPC after EBRT.
Key words : recurrent
nasopharyngeal
carcinoma; External beam radiotherapy; 125I seed
implantation brachytherapy; overall survival; local control; side
effects.