Simultaneous development of adenocarcinoma and gastrointestinal stromal tumor (GIST) in the stomach: case report.
BACKGROUND
Gastrointestinal stromal tumors (GISTs) and adenocarcinoma are distinct neoplasms originating from different cell layers. Approximately 20% of patients with GIST develop other cancers.


METHODS
We report a case of the coexistence of adenocarcinoma and gastrointestinal stromal tumor (GIST). Gastric endoscopy showed the ulcerated tumor with bleeding along the lesser curvature of the proximal stomach and a submucosal nodule that measured about 3 cm in diameter in the lower part of the stomach body. Their pathological examination showed gastric cancer (poorly differentiated diffuse adenocarcinoma) and GIST (low-risk category). Further, immunohistochemical staining for C-kit and CD34 was positive, while that for SMA and S-100 was negative.


CONCLUSIONS
Although it is not easy to speculate on the coexistence of adenocarcinoma and GIST, pre-and post-operative diagnoses may be essential, and such cancer development is not considered to be unusual.
Department of Surgery, Kansai Medical University, Hirakata, Japan. yamamotd@hirakata.ac.jp
Daigo
D
Yamamoto
Yoshinori
Y
Hamada
Yu
Y
Tsubota
Katsuhiro
K
Kawakami
Chizuko
C
Yamamoto
Mitsuo
M
Yamamoto
D000230:Adenocarcinoma / Q000150:complications* / Q000473:pathology* / Q000601:surgery; D018952:Antigens, CD34 / Q000032:analysis; D046152:Gastrointestinal Stromal Tumors / Q000150:complications* / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000209:etiology* / Q000473:pathology* / Q000601:surgery; D011379:Prognosis; D013274:Stomach Neoplasms / Q000150:complications* / Q000473:pathology* / Q000601:surgery
D018952:Antigens, CD34