Massive Gastric Juvenile Polyposis: A Clinicopathologic Study Using SMAD4 Immunohistochemistry

OBJECTIVES

Juvenile polyps involving the stomach are uncommon. Massive gastric juvenile polyposis is even rarer.

METHODS

We describe the clinicopathologic features of nine cases of massive gastric juvenile polyposis.

RESULTS

All patients had anemia; four had hypoalbuminemia. The polyps were composed predominantly of dilated crypts lined by columnar epithelium and abundant edematous stroma with mixed inflammatory infiltrates. One patient had a poorly differentiated adenocarcinoma, arising in juvenile polyp-associated intraepithelial neoplasia. A second patient had a well-differentiated intramucosal adenocarcinoma arising in a juvenile polyp with high-grade dysplasia. Three of our cases had polyposis restricted to the stomach. Six (66.6%) had loss of SMAD4 immunoreactivity, making them subject to severe bleeding and hypoproteinemia, as well as developing severe dysplasia or adenocarcinoma.

CONCLUSIONS

SMAD4 immunohistochemstry is a helpful ancillary diagnostic test in cases of suspected juvenile polyposis syndrome involving the stomach.

Lymphangiomatous Lesions of the Gastrointestinal Tract: A Clinicopathologic Study and Comparison Between Adults and Children

OBJECTIVES

Lymphangiomatous lesions involving the gastrointestinal (GI) tract remain incompletely characterized, and their clinical and histopathologic features have not been systematically evaluated. The distinction between a primary lymphatic malformation (lymphangioma) and a dilation of existing lymphatics (lymphangiectasia) is of clinical significance, since lymphangiectasia may occur in the setting of lymphatic obstruction due to an unsampled malignancy. We describe clinical and morphologic features of lymphangiomas of the GI tract in adult and pediatric populations and contrast them with lymphangiectasia.

METHODS

We performed a retrospective review of adult and pediatric lymphangiomas and lymphangiectasia involving the GI tract.

RESULTS

Thirty-six cases of lymphangioma and lymphangiectasia were retrieved, and clinical presentation and histologic features were compared. Lymphangiomas had distinct clinical presentations in adults and children, with adult lesions being more frequently asymptomatic and more frequently involving the superficial mucosal layers of the GI tract. Microscopically, lymphangiomas mostly consisted of confluent dilated spaces with a smooth muscle component. This appearance differed from lymphangiectasia, which lacked a complete distinct endothelial or smooth muscle lining and diffusely involved the mucosa and submucosa.

CONCLUSIONS

Morphologic features of GI tract lymphangiomas can be reliably distinguished from lymphangiectasia by clinical and pathologic characteristics.

Beta-human chorionic gonadotropin expression in recurrent and metastatic giant cell tumors of bone: a potential mimicker of germ cell tumor

Giant cell tumors of bone (GCTs) are generally benign, locally aggressive neoplasms that rarely metastasize. The beta subunit of human chorionic gonadotropin (beta-hCG) is expressed in syncytiotrophoblasts and several nongynecologic neoplasms but has not been described in GCT. At our institution, we observed cases of elevated beta-hCG in patients with GCT leading to diagnostic difficulty and in one case, concern for metastatic choriocarcinoma. This study aims to determine the frequency of beta-hCG expression in GCT and any relationship to clinical aggressiveness. We evaluated tissue expression of beta-hCG by immunohistochemistry with 58% of cases staining for beta-hCG. Additionally, 2 of 11 patients with available serum and/or urine beta-hCG measurements demonstrated elevated beta-hCG due to tumor. It is important to be aware of beta-hCG expression by GCT and the potential for elevated urine and serum beta-hCG levels in patients with GCT so as to avoid misdiagnosis of pregnancy or gestational trophoblastic disease.