Signet ring cell carcinoma in a juvenile polyp

Solitary juvenile polyp of the rectum with intramucosal adenocarcinoma

We describe a case of solitary juvenile polyp of the rectum with intramucosal adenocarcinoma. A 55-year-old man presented to our hospital for evaluation after a positive fecal occult blood test. Colonoscopy revealed a pedunculated polyp of 25 mm in size which has an irregular shape and pale red color on the rectum. The polyp had a proliferation of blood vessels and an invisible surface pattern. Endoscopic mucosal resection was performed. Pathologically, it was diagnosed as a solitary juvenile polyp with intramucosal well-differentiated adenocarcinoma. When we encounter juvenile polyps, the possibility of malignancy should be taken into consideration for treatment.

Characteristics and potential malignancy of colorectal juvenile polyps in adults: a single-center retrospective study in China

BACKGROUND

Colorectal juvenile polyps are rare and generally considered benign in adults. Carcinogenesis or neoplastic changes are rarely mentioned in the literature. We systematically evaluated the characteristics and potential malignancy of colorectal juvenile polyps in adults.

METHODS

We retrospectively reviewed the medical records of 103 adults diagnosed with colorectal juvenile polyps from September 2007 to May 2020 at our hospital. The characteristics, endoscopic findings, occurrence of intraepithelial neoplasia, carcinogenesis and diagnostic value of chicken skin mucosa (CSM) were analyzed.

RESULTS

The average age of patients with juvenile polyps was 43.2 years (range, 19 to 78 years). A total of 101 patients (101/103, 98.1%) had a single juvenile polyp, and two patients had multiple polyps (107 polyps in total). Polyp sizes ranged from 0.5 to 5 cm. One (1/107, 0.9%) juvenile polyp was cancerous, and 7 (7/107, 6.5%) developed low-grade intraepithelial neoplasia. Neoplasia and cancerization did not appear in the two patients with multiple polyps. A 27-year-old female had a 2-cm polyp with well-differentiated adenocarcinoma in the mucosa in the sigmoid colon with erosion on the surface. CSM was observed adjacent to 17 polyps, which were all located in the rectum and sigmoid colon, and one polyp showed low-grade intraepithelial neoplasia.

CONCLUSIONS

Colorectal juvenile polyps occur in a wide range of locations and in variable sizes and numbers. These polyps are solitary in most patients and have neoplastic potential. CSM is not a tumorigenic marker in colorectal juvenile polyps and usually occurs in the distant colorectum. Colorectal juvenile polyps in adults may progress from low-grade intraepithelial neoplasia to high-grade intraepithelial neoplasia and then to carcinoma and should be treated when discovered and regularly followed as colorectal adenomas.