A 67-year-old woman, current smoker (25 pack-years), with stage IV lung adenocarcinoma diagnosed 18 months before, under chemotherapy, presented to the emergency department with progressive dysphagia, abdominal pain, nausea and vomiting in the last 15 days. Laboratory data revealed hypochromic and microcytic anemia (hemoglobin 7.4g/dL). Esophagogastroduodenoscopy showed an extensive ulcerated lesion with elevated irregular borders in the posterior wall of the gastric lower body (Fig. 1A); biopsies were obtained, and pathological examination of specimens demonstrated poorly differentiated invasive adenocarcinoma (Fig. 1B and C). In the immunohistochemical studies, tumor cells were positive for thyroid transcription factor 1 (TTF-1) (Fig. 1D) and cytokeratin 7 (CK-7) (Fig. 1E); and negative for cytokeratin 20 (CK-20), consistent with metastasis from lung adenocarcinoma. As the patient's general condition was quickly deteriorating and considering her poor overall performance status, best supportive care management was the recommended treatment. She died 21 months after the initial diagnosis.
(A) On the posterior side of the gastric lower body, a deep ulcer with elevated edges was observed, with an extension of about 5cm – biopsies of the edges were performed. (B) and (C) Hematoxylin-and-eosin staining of the gastric lesion showed a papillary pattern and cohesive neoplastic cells forming irregular gland-like tubular structures, findings compatible with poorly differentiated adenocarcinoma. The positivity of (D) thyroid transcription factor 1 (TTF-1) and (E) cytokeratin 7 (CK-7) stained in brown was determined by immunohistochemistry.
Metastasis to gastrointestinal tract from lung cancer is uncommon with reported incidences ranging from 0.5% to 10%. The specific occurrence of gastric metastasis ranges from 0.2 to 0.5% thus representing a very rare event. Immunochemistry is a very useful tool for differentiating primary gastric cancer from gastric metastasis in equivocal cases.1,2
FundingNo funding.
Conflicts of InterestsNo conflicts of interests.
