Multiple Polypoid Colonic Metastases from Primary Gastric Signet Ring Cell Carcinoma

Correspondence To the Editor: Gastric carcinoma is a common gastrointestinal (GI) malignancy while signet ring cell carcinoma (SRCC) is a well-known poorly differentiated histological type that has a strong tendency for metastasis. The dissemination of gastric carcinoma mainly presents in three patterns. The most common approach for metastasis is through the regional lymph node. Hematogenous spread is also very common and mostly occurs in the liver, lungs, bones, and adrenal gland. In addition, direct adjacent invasion, peritoneal seeding, and Krukenberg tumor are less seen but are also very important in clinic with poor prognosis. In this report, we present a case of rare colonic metastases in the form of multiple polyps from primary gastric SRCC. A 48-year-old women presented with a symptom of the upper abdominal pain accompanied by regurgitation and hiccup for the past year. On June 26, 2015, she underwent esophagogastroduodenoscopy in a local hospital, which revealed a large ulcerative lesion in the greater curvature near the antrum of the stomach, and biopsy of the lesion indicated signet ring cell adenocarcinoma. Abdominal computed tomography (CT) scan with intravenous contrast was also performed, which revealed the diffused uneven thickening of the antrum of the stomach without any adjacent infiltration. Then, the patient was admitted to the Minimally Invasive Surgery Center of Ruijin Hospital for laparoscopic distal gastrectomy plus D2 lymph node dissection and Roux-en-Y anastomosis on July 10, 2015. Postoperative UICC staging of the primary tumor was pT4aN2bM0, Stage IIIC. She recovered well from surgery and was discharged. Since postoperative follow-up revealed no decrease in tumor markers, total colonoscopy was performed on the patient, which revealed several discrete polypoid lesions in the transverse and ascending colon, measuring 5–10 mm in diameter. Almost all lesions had depressions on the tip, and the margin was unclear [Figure 1a]. The largest one was in the form of a flat discoid shape with erosion at the center [Figure 1b]. Colonoscopy-guided biopsy revealed a signet ring cell adenocarcinoma. Then, a laparoscopic complete mesocolic excision for right-hemicolon cancer was conducted, and no proof for distant metastasis was found during the intraoperative exploration. The pathological report came out several days later, which was quite out of our expectation and revealed six lesions in the specimen. All of which were confirmed as SRCC, which has grown through the seroma and infiltrated the nerves and vessels. Regional lymph nodes were 15/23 positive for tumor metastases (pT4aN2bM0, Stage IIIC). …