A 59-year-old woman presented with progressive dysphagia. At esophagogastroduodenoscopy,
a mass 4 cm long and 2 cm wide was observed in the cervical esophagus. It was a smooth-surfaced
lesion, with blood vessels branching on top of it (Figure [1]). An initial biopsy showed normal results, and the endoscopist suspected a stromal
tumor. The patient was referred for an endoscopic ultrasound (EUS) examination, which
was carried out with a miniprobe (Olympus UM-2R, 12 MHz). EUS revealed a homogeneous
hypoechoic tumor arising from the mucosa and infiltrating the submucosa (Figure [2], [3]). This feature is atypical for a stromal tumor, which usually appears as a mass
lesion with confined borders that arises from the submucosa or muscularis layers.
EUS identified the mucosal part of the tumor, and repeated pinhole biopsies were taken.
Figure 1 Esophagogastroduodenoscopy showed narrowing of the esophageal lumen due to a smooth-surfaced
mass. There were dilated blood vessels on top of the mass.
Figure 2 The endoscopic ultrasound miniprobe examination showed that the hypoechoic tumor (Tu)
was infiltrating the hyperechoic submucosa (SM), without forming a defined margin.
The muscle layer (M) was normal. A vessel (Ve) was noted outside the opposite wall.
Figure 3 The mucosa (Mu) was intact over most of the tumor (Tu) site, as the tumor was mainly
infiltrating the submucosa (SM), without breaking the mucosa. The muscle layer (M)
was apparently thickened due to oblique scanning. A vessel (Ve) was noted outside
the opposite wall.
The second histological assessment showed that the lesion was a small-cell cancer
(Figure [4]). Positron-emission tomography (PET) showed that there were no other primary or
secondary tumor sites. The patient was diagnosed as having limited primary small-cell
cancer in the esophagus. She received chemoradiotherapy treatment over a 3-month period.
Follow-up PET and CT examinations 7 months later showed that the primary tumor had
completely resolved, with the maximum standardized uptake value (SUV) having decreased
from 9.4 to 3.1. However, the treatment was complicated by an esophageal stricture,
which required repeated endoscopic dilation procedures. Repeated biopsies did not
reveal any malignant cells.
Figure 4 The histological analysis showed esophageal squamous epithelium in the upper left
corner, with infiltrative sheets of small to medium-sized hyperchromatic malignant
cells with stippled chromatin in the rest of the image (hematoxylin-eosin, original
magnification × 40).
Primary esophageal small-cell cancer is an uncommon condition, representing 1.0 -
2.8 % of esophageal cancers [1]
[2]. Patients usually present late with anorexia, weight loss, and dysphagia due to
tumor obstruction. To the best of our knowledge, there have been no previous reports
in the literature on the EUS features of esophageal small-cell cancer. In this patient,
the lesion mimicked a stromal tumor. EUS raised the suspicion of malignant disease,
which was subsequently confirmed by the guided biopsy.
Endoscopy_UCTN_Code_CCL_1AB_2AC_3AB
