2 Results
In the present study, 140 consecutive patients were screened for
eligibility and 130 patients were enrolled in the clinical trial. Ten
patients were excluded (4 were lost to follow-up and 6 were unbearable
to side effects during concurrent chemoradiotherapy). Patients were
stratified into 3 groups based on the degree of carotid artery
involvement: <180º, n=37; 180º≤IG<270º, n=32; and
≥270º, n=61.
Three patients whose primary tumor located in the nasopharyngeal recess
and carotid artery invasion ≥270° died of massive neck hemorrhage (Table
3; Fig.2).They were confirmed by repeated nasal endoscopy (gray-white
necrotic material) and MRI enhancement of nasopharynx (gray-black
necrotic material, non-neoplastic tissue, T1 phase is low signal, T2
phase is slightly high signal) prior to hemorrhage.No radiation-induced
carotid pseudoaneurysms were confirmed by DSA.
The median follow-up time was 25 months (range 5-97 months). During the
follow-up period, 20 patients died, 22 patients progressed (including 3
patients with recurrence, 2 with cervical lymph node metastasis, 16 with
distant metastasis, and 1 with secondary primary cancer). The overall
5-year survival rates were PFS=75.2%, DMFS=76.8%, LNRFS=90.0%,
LRFS=93.9%, NRFS=95.8% and OS=87.2% (Fig.3-1).
Univariate analysis showed that gender, age, pathological type and
degree of carotid artery involvement were not significantly associated
with survival. Clinical stage, induction chemotherapy regimen,
concurrent chemotherapy regimen and EGFR inhibitors were significantly
associated with PFS and DMFS (P<0.05). Hemoglobin levels
during radiotherapy were significantly associated with DMFS, PFS and OS
(P<0.05) (Supplementary Table 1).
Multivariate analysis showed that EGFR inhibitor was an independent
prognostic factor for DMFS and PFS (P<0.05). Hemoglobin level
during radiotherapy was an independent prognostic factor for OS
(P<0.05) (Supplementary Table 2; Fig3-2~4).
Comparison of three degrees of the carotid artery invasion
(<180°, 180°≤IG<270°, ≥270°) suggested that the
5-year PFS was 82.3%, 72.4% and 59.5%, respectively; 5-year DMFS was
85.8%, 78.0% and 77.1%, respectively; 5-year LNRFS was 95.8%, 90.4%
and 77.1%, respectively; 5-year LRFS was 95.8%, 100% and 77.1%,
respectively; 5-year NRFS was 100%, 90.4% and 100%, respectively; and
5-year OS was 92.9%, 85.2% and 78.0%, respectively (Supplementary
Fig.1-6).