Results
A total of 99 patients were enrolled in this study. The demographic data
of the patients are listed in Table 1. Age ranged from 35 to 79 years,
with a mean age of 57 years. Most patients had a history of carcinogen
exposure, including tobacco consumption, alcohol consumption, and betel
quid chewing. In accordance with the American Joint Committee on Cancer
(7th Edition),14 15 patients (15%) were Stage I or
II, 15 (15%) were Stage III, and 69 (70%) were Stage IV. Forty-one
patients (41%) had received radiation therapy or chemoradiation therapy
as primary treatment. Nineteen patients (19%) had a history of SPMs.
The results of IEE examination are summarized in Table 2. A positive
finding of second primary ESCN was detected in 31 patients (31%). The
prevalence of ESCN in the ND group and the FU group were 27% (8
patients) and 33% (23 patients), respectively.
Among the eight patients with second primary ESCNs in the ND group, a
total of 10 lesions were found, and the pathologic examinations showed
that the lesions included severe dysplasia, carcinoma in situ, SCC, and
non-SCC. The locations of the second primary ESCNs included the upper
third, middle third, and lower third segments of the esophagus, and one
patient had multiple-site second primary ESCNs.
In the FU group, second primary ESCNs were detected in 23 patients, and
26 lesions were found. The histology of second primary ESCNs included
severe dysplasia, carcinoma in situ, and SCC. The sites of lesions
involved upper third, middle third, and lower third segments of the
esophagus.
The staging of second primary ESCNs in the ND and FU groups are
presented in Table 2. All second primary ESCNs in the ND group and 74%
of second primary ESCNs in the FU group were determined as early-stage
(from Stage 0–II) lesions.
Table 3 shows the results of the comparison of patient characteristics
and the indices of primary tumors between patients in the FU group with
and without positive lesions. The patient characteristics and the
indices of primary tumors were similar between these two groups,
including carcinogen exposure, TNM classification of the primary tumor,
treatment modality, and presence/absence of symptoms at UGI exam. Only
the history of previous UADT SPMs showed significantly differences.
Subgroup analysis was conducted on the FU group with second primary
ESCNs (Table 4). Seven patients had symptoms (dysphagia, foreign body
sensation) at the time they received IEE. There were significant
differences between the two subgroups in clinical T‑classification and
treatment modality of second primary ESCNs. Nearly half of the second
primary ESCNs were classified as Tis lesions (44%) in patients without
symptoms in the FU group compared with 0% in those with symptoms
(p = 0.0359). The number of patients who were able to be treated
with minimal invasive therapy (defined as endoscopic submucosal
dissection, endoscopic mucosal resection, endoscopic esophagectomy) was
significantly higher among patients without symptoms than those with
symptoms. (75% vs. 0%, p = 0.0013).
The overall malignant and non-malignant findings in IEE examinations are
shown in Table 5. In the 99 patients of hypopharyngeal cancer with IEE,
31 (31%) were found to have malignant lesions; while 46 (46%) had no
malignant findings, including reflux esophagitis in 42 (42%), low-grade
dysplasia in 2 (2%), and moderate-grade dysplasia in 2 (2%).