A case of gastric carcinosarcoma

Carcinosarcoma is a malignant tumor consisting of both epithelial and mesenchymal elements that rarely occurs in the stomach [1]. We present a case of gastric carcinosarcoma presenting as anemia and with interesting endoscopic features.

An 83-year-old woman with a history of pulmonary tuberculosis underwent esophagogastroduodenoscopy (EGD) because of anemia (hemoglobin 6.3 g/dL) that had been diagnosed 2 weeks previously. EGD revealed an ulcerative lesion in the gastric antrum ([Fig. 1]). An exophytic mass was protruding from the ulcer base and was covered with whitish exudates and clotted blood ([Fig. 2]). A biopsy specimen was obtained from the ulcerative lesion, and a pathological diagnosis of adenocarcinoma was made. The ulcerative lesion was suspected to be the source of bleeding and the cause of the patient’s anemia. No other source of bleeding was evident. The patient subsequently underwent gastrectomy and extirpation of the affected lymph nodes ([Fig. 3]). Histopathologically, the tumor was seen to involve all the layers of the gastric wall and to consist of both epithelial and spindle cells ([Fig. 4]). The epithelial cells had a solid growth pattern with foci of tubular growth ([Fig. 5]). Proliferation of spindle cells with marked cytological atypia was seen across most of the tumor ([Fig. 6]). Histochemistry was positive for cytokeratin in the epithelial component. The spindle cells stained intensively for vimentin, although neither muscular nor neural differentiation was evident. The tumor was finally diagnosed as a gastric carcinosarcoma.

Fig. 1 Endoscopy showing an ulcerative lesion in the gastric antrum.

Fig. 2 Endoscopy showing an exophytic mass protruding from the base of the gastric ulcer.

Fig. 3 The resected specimen with the protruding mass devoid of mucosa.

Fig. 4 Histopathological section showing the tumor involving all the layers of the gastric wall.

Fig. 5 Epithelial cells displaying a solid growth pattern, with foci of cells showing tubular growth (hematoxylin and eosin; magnification × 200).

Fig. 6 A large part of the tumor was seen to consist of proliferating spindle cells with marked cytological atypia (hematoxylin and eosin; magnification × 400).

Carcinosarcomas in the stomach may be polypoid, exophytic, or endophytic, with generally ulcerated surfaces; they frequently infiltrate the gastric wall in the antral or pyloric region and form large tumor masses [2] [3] [4] [5]. Gastric carcinosarcoma should be taken into consideration when a giant gastric tumor shows endoscopic features that are atypical of gastric cancer.

Endoscopy_UCTN_Code_CCL_1AB_2AD_3AB

References

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• 3 Kayaselcuk F, Tuncer I, Toyganozu Y. et al . Carcinosarcoma of the stomach.  Pathol Oncol Res. 2002;  8 275-277
• 4 Maiorana A, Fante R, Maria C esinaro. et al . Synchronous occurrence of epithelial and stromal tumors in the stomach: a report of 6 cases.  Arch Pathol Lab Med. 2000;  124 682-686
• 5 Ikeda Y, Kosugi S, Nishikura K. et al . Gastric carcinosarcoma presenting as a huge epigastric mass.  Gastric Cancer. 2007;  10 63-68