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Paper text:
hamartomatous polyps are uncommon and usually found as a part of peutz - jegher syndrome , a rare autosomal dominant disorder associated with mucocutaneous pigmentation and family history .
hamartomatous polyps are composed not only of epithelial elements , but also of bundles of smooth muscle cells .
such hamartomatous gastric polyps are almost always found in patients with peutz - jeghers syndrome , in association with intestinal polyps . in hamartomatous polyps
, there is an increased risk of malignancy in both the gastrointestinal and extra - intestinal sites [ 2 - 4 ]
. the risk increases with age ( range , 1 to 33% ) between 30 and 60 years .
fifty seven years - old man with a history of epigastric pain was transferred from an outside hospital with the diagnosis of early gastric cancer . physical examination and laboratory
no pigmentation was found on the lips and perioral region , hands , buccal mucosa , and feet .
endoscopy revealed two masses on the greater curvature side of the prepyloricantrum : a round , 1 cm polypoid lesion and an irregular 3 cm elevated mass with superficial ulcerations ( fig .
1a ) and another 6 cm pedunculated polypoid mass on the greater curvature side of prepyloricantrum ( fig .
upper gastrointestinal series showed three polypoid lesions in the gastric antrum which was considered as an advanced , borrmann type i carcinoma preoperatively ( fig .
subsequently , the patient underwent a radical subtotal gastrectomy , which revealed a 6  5 cm mass confined to the mucosa of the greater curvature of the lower body and another 5.5  2 cm mass invading into the submucosa of the greater curvature of the antrum ( fig .
the 5.5  2 cm sized mass looked like two masses , but was a fused mass intraoperatively .
microscopic analysis of the specimen revealed adenocarcinoma within the hamartomatous polyps demonstrated by proliferation of smooth muscle bundles within the lamina propria and between carcinomatous glands ( fig .
4a ) with evidence of epstein - barr virus ( ebv ) in both lesions ( fig .
the patient had an uneventful postoperative course and was discharged home on the 9th postoperative day .
reported four cases of patients with multiple benign gastric hamartomatous polyps that were not associated with polyposis coli .
however , syndrome - associated hamartomatous polyps may have malignant potential as cases of malignant hamartoma have been described [ 8 - 10 ] . from our review of the english - language literature
, this case report appears to be the first documented case of adenocarcinoma derived from gastric hamartomatous polyps which was not accompanied by a known syndrome .
we present a case report of a patient with malignant gastric hamartomatous polyps in the absence of familial polyposis nor pigmentation .
furthermore , this case exhibited positive expression via in ebv - encoded rna ( eber ) in situ hybridization .
to date , there is no report about incidence of adenocarcinoma in hamartomatous polyps in eber - positive in situ hybridization .
most hamartomatous polyps in the stomach occur in patients with adenomatous polyposis coli and dysplasia . 
 the authors report a case of a 57-year - old man without prior history of polyposis coli who presented with adenocarcinomas derived from hamartomatous polyps in the stomach . 
 the patient underwent a radical subtotal gastrectomy with billroth i anastomosis . 
 pathology revealed adenocarcinomas with moderate differentiation without evidence of lymph node metastasis in 60 nodes . 
 we report a case of gastric cancers arising from de novo gastric hamartomatous polyps .