Collision tumor of choriocarcinoma and small cell carcinoma of the stomach: A case report. Int J Surg Case Rep. 2017;37:216-220. [PMID: 28709051 PMCID: PMC5508625 DOI: 10.1016/j.ijscr.2017.06.055]

Collision Tumor of the Stomach

Collison tumor of the stomach is rare, and its endoscopic and pathological features remain poorly described. A 70-year-old woman was referred to our hospital for examination and treatment of undifferentiated gastric cancer. Esophagogastroduodenoscopy revealed a whitish, superficial elevated lesion in contact with a reddish, superficial depressed lesion from the anterior wall of the gastric angle and antrum to the lesser curvature. Laparoscopic distal gastrectomy was performed for preoperative diagnosis of suspected early gastric cancer presenting as a differentiated and undifferentiated collision tumor, which led to the lesion being diagnosed as collision tumor, tub1-tub2+por1-sig, pT1a (M), ly0, v0, N0, stage IA. To our knowledge, this report represents a valuable addition to the collision tumor literature describing a rare case of preoperatively diagnosed collision tumor of the stomach.

Report of three cases of gastric choriocarcinomas-an emphasis on morphologic changes in the non-affected gastric mucosa

Primary gastric choriocarcinomas (PGC) are very rare and aggressive neoplasms with a worrisome prognosis. Most cases are reported in Asia and presented in middle-aged adults with male predominance. Most cases are associated with an intestinal adenocarcinoma; however, the pathogenesis of this tumor is uncertain. No previous reports exist of the characteristics of the non-tumoral stomach in these patients, and this data that could help to clarify their pathogenesis. We presented a series of three cases of PGC in Latin American patients, emphasizing the characteristics of non-neoplastic mucosa.

Primary gastric choriocarcinoma - a rare and aggressive tumor with multilineage differentiation: A case report

BACKGROUND

Primary choriocarcinoma of the stomach (PCCS) is a rare tumor, with fewer than 60 cases published in the English-language literature up to December 2018. In this paper, we present the complex immunoprofile of one PCCS and a hypothesis regarding its histogenesis.

CASE SUMMARY

A 66-year-old previously healthy male underwent an emergency palliative gastrectomy for a gastric obstructive tumor. The histologic examination and immunoprofile of tumor cells showed a mixed tumor that consisted of choriocarcinoma (90%) and moderate differentiated adenocarcinoma (10%), with hepatic metastases (Stage pT2NxM1L1V1R0) and microsatelite stable status. The patient died one month after surgery. The tumor cells showed focal positivity for CDX2 (adenocarcinoma component), HCG (choriocarcinoma) and CD138 (plasmacytoid carcinoma component) and were negative for HER-2, α-fetoprotein, VEGF, maspin and markers of epithelial-mesenchymal transition. The gastric mucosa cells displayed positivity for CDX2, Hepar A and CD138. The complex immunoprofile and literature data synthesis prove that the gastric mucosa cells can present a multilineage differentiation.

CONCLUSION

PCCS should be considered as an aggressive variant of microsatellite stable gastric adenocarcinoma of an epithelial type, and not a germ cell tumor.