Gastroenterol Res

Gastroenterology Research, ISSN 1918-2805 print, 1918-2813 online, Open Access

Article copyright, the authors; Journal compilation copyright, Gastroenterol Res and Elmer Press Inc

Journal website http://www.gastrores.org

Original Article

Volume 11, Number 1, February 2018, pages 25-30

Metastatic Renal Cell Carcinoma as Solitary Subcentimeter Polypoid Gastric Mucosal Lesions: Clinicopathologic Analysis of Five Cases

Figures

Figure 1. Representative endoscopic appearance of metastatic renal cell carcinoma as gastric mucosal lesions. (a) Metastatic renal cell carcinoma presented as a 0.4 cm polyp (arrow) without ulceration in the gastric body (case 2). (b) Metastatic renal cell carcinoma presented as a 0.8 cm sessile polyp with ulcerated surface in the gastric body (case 4).

Figure 2. Representative photomicrographs of metastatic clear cell renal cell carcinoma as gastric mucosal lesions. The lesions demonstrated a bland clear cell proliferation within the lamina propria (a). At the interface between the carcinoma and benign gastric mucosa, the clear cells infiltrated among gastric glands without gland destruction (b). The individual tumor cells showed cytoplasmic vacuoles, small nuclei, nuclear membrane irregularity, and occasional small pinpoint nucleoli (c). Immunohistochemistry demonstrated immunoreactivity for pancytokeratin (d), RCC (e), and PAX8 (f). (a, × 100; b, d, e, f, × 200; c, × 400).

Figure 3. Metastatic renal cell carcinoma with many foamy histiocytes intermingled with the tumor cells (a). However, at least focal nuclear atypia was appreciated in the tumor cells, and immunohistochemistry for CD68 showed patchy staining (c). In contrast, gastric xanthomas were completely devoid of atypia and the cytoplasm was foamy rather than clear (b). Immunoreactivity for CD68 was strong and diffuse in xanthomas (d) (a, b, c, d, × 200).

Table

**Table 1.** Clinicopathologic Characteristics of Metastatic Renal Cell Carcinoma as Subcentimeter Polypoid Gastric Mucosal Lesions
	Year*	Age/sex	Symptoms	Location	Size (mm)	Endoscopic characteristics	Interval^#	Primary stage	Other sites of metastases	Reference
GERD: gastroesophageal reflux disease; GI: gastrointestinal; N/A: no previous history of renal cell carcinoma. *Year of gastric metastasis for the current cases, year of publication for the referenced cases. #Years from the primary renal cell carcinoma diagnosis to the detection of gastric metastasis.
1	2017	84/M	Dysphagia, GERD	Body	6	Sessile polyp	5	pT1NxMx	None	Current
2	2015	58/M	Occasional GERD	Fundus	4	Sessile polyp	6	pT2N0Mx	Adrenal gland, pancreas, liver, lung (2012); brain (2015)	Current
3	2011	74/M	Upper GI bleeding	Antrum	10	Sessile polyp with ulcerated surface	N/A	Unknown	None	Current
4	2008	72/F	GERD, anemia	Body	8	Sessile polyp with ulcerated surface	N/A	pT2N0M1	Liver, pancreas (2009)	Current
5	1998	66/M	Melena, anemia	Body	10	Friable mass	10	pT1aN0Mx	Lung, pancreas, mesentery (1998); brain (2000)	Current
6	2012	59/F	GERD, back pain	Fundus	5	Sessile	N/A	Unknown	Brain (unknown)	[6]
7	2012	60/F	Anemia	Body	6, 6	Non-ulcerated, benign appearing polyps	0.41	pT1bNX	Lung, bone, and right nephrectomy bed (2011)	[7]
8	2012	79/M	Abdominal pain	Body	6	Erosive lesion	synchronous	pT1bN0M1	None	[8]
9	2007	Unknown	Severe anemia with melena	Body	10	Polypoid	10	Unknown	None	[9]