A 76-year-old man was referred to our endoscopic unit with hematochezia and anemia.
He had been receiving palliative treatment, including radiation therapy, for a primary
stage IV parotid gland cancer. Colonoscopy showed that the mucosa of the terminal
ileum had prolapsed into the colonic lumen, and a flat elevated lesion, 8 mm in diameter
and mimicking a small flat adenoma, was seen on the prolapsed ileal mucosa (Figure
[1]). On palpation with biopsy forceps, the lesion felt more solid and harder than an
ordinary adenoma. An endoscopic biopsy sample was sent for histological evaluation,
and the findings were consistent with a metastatic parotid gland cancer (Figure [2]), the histological features being quite similar to those of the primary tumor biopsied
previously. No definite source of bleeding was detected on upper and lower gastrointestinal
endoscopic examinations. Palliative treatment was continued and the patient died 4
months later.
Figure 1 Colonoscopy revealed a small flat elevated lesion on the ileal mucosa that had prolapsed
into the colonic lumen, which felt solid and hard on palpation with biopsy forceps
(a). Chromoendoscopy using 0.4 % indigo carmine dye clearly defined the margin of the
metastatic lesion (b).
Figure 2 Histologically, the biopsy specimen from the flat elevated lesion showed diffuse infiltration
of parotid gland carcinoma cells in both the mucosa and the submucosal layer.
This case of ileal metastasis from a parotid gland cancer appears to be the first
of its kind to have been reported. As the presence of distant metastasis from head
and neck cancer is associated with a poor prognosis, treatment is usually performed
in a palliative setting [1]. A secondary gastrointestinal tumor detected in the early phase of the disease has
never been reported before. Generally among gastrointestinal metastases, the small
intestine is the most common site of secondary involvement of various cancers; metastases
elsewhere in the gastrointestinal tract are relatively rarer, with the stomach and
large intestine involved less frequently than the small intestine, though the esophagus
is affected the least often [2]. Modes of gastrointestinal metastasis include hematogenous or lymphogenous spread,
direct invasion by a noncontiguous primary carcinoma along the fascia and mesenteric
attachments, and dissemination via the peritoneal fluid [2]. Histologically, because the biopsy specimen in this case showed marked lymphatic
permeation of tumor cells, the morphology of the lesion was considered to have been
created by lymphogenous spread of solid tumor cells.
Endoscopy_UCTN_Code_CCL_1AC_2AC
