Hypoplasia of the inferior vena cava with azygous continuation presenting as recurrent leg deep vein thrombosis.

Azygous continuation of the inferior vena cava is a rare congenital malformation. It occurs because of atresia of the retrohepatic segment of the inferior vena cava. The disorder has been described mainly as an incidental finding associated with a number of congenital malformations, including cardiovascular, tracheobronchial, and other visceral malformations. Therapeutic intervention is aimed primarily at accompanying malformations. We report a case of hypoplasia of the inferior vena cava with azygous continuation in a 30-year-old man who presented with recurrent deep venous thrombosis.

Epithelioid angiosarcoma associated with a Dacron vascular graft.

Angiosarcoma developed at the site of a Dacron vascular prosthesis 8 years after an aortobifemoral bypass graft insertion. The tumor was composed of epithelioid cells, which showed positive staining for cytokeratin and expression of the common endothelial markers CD31, CD34, and von Willebrand factor. Ultrastructural examination showed aggregates of large cells with intercellular lumina and focal perinuclear whorls of intermediate filaments. The patient, who had abdominal pain and weight loss, died of disseminated pelvic and abdominal disease 6 months after diagnosis. Sarcomas associated with vascular Dacron grafts and angiosarcomas associated with metal or polymer foreign bodies are rare. Their development is probably analogous to the common experimental development of foreign body-associated sarcomas in rodents. Physicians caring for patients with vascular grafts or metal foreign bodies should be aware of this complication.

Anorectal malignant melanoma. A clinicopathologic study, including immunohistochemistry and DNA flow cytometry.

BACKGROUND: Anorectal malignant melanoma is a rare tumor with an extremely poor prognosis. DNA flow cytometric study as well as detailed immunohistochemical study have not been reported previously. METHODS: Eighteen cases of anorectal melanoma were studied, including immunohistology for melanoma markers and epithelial markers and DNA flow cytometric study of paraffin blocks. RESULTS: Most patients were Ashkenazi Jews, compared with Sephardi Jews and Arabs. Of the 17 patients followed, 14 died of disease at 4-39 months from presentation. Three patients were alive with disease at 12, 53, and 72 months of follow-up. Tumor thickness ranged from 3-35 mm (mean, 12.8 mm). The 2 long term survivors had tumor thickness < or = 7 mm. No correlation was found between the mode of primary surgical treatment (8 patients: abdominoperineal resection; 10 patients: local excision) and outcome. Vimentin, HMB-45, and S-100 protein stainings were positive in 18, 17, and 15 tumors, respectively. Polyclonal carcinoembryonic antigen (CEA), broad-spectrum cytokeratin, epithelial membrane antigen, monoclonal CEA, and TAG-72 (B72.3) stainings were positive in 13, 3 (only focal and rare staining), 2, 0, and 0 tumors, respectively. Thirteen tumors had adequate material for DNA analysis, and all were DNA aneuploid. S-phase fraction could be assessed in 11 tumors and ranged from 7.7-24% (mean, 14%). An S-phase fraction of < 10% was observed in the 2 long term survivors. CONCLUSIONS: Anorectal melanoma in this study carried a grave prognosis. The frequent staining for polyclonal CEA (with negative monoclonal CEA staining) was probably due to nonspecific cross-reacting antigens. The occasional staining for epithelial markers warrants a comprehensive immunohistochemical study to ensure a correct diagnosis, especially in small biopsies of amelanotic undifferentiated tumors that lack junctional changes. The aneuploidy of all tested tumors reflected their highly malignant behavior. A trend toward longer survival was observed in patients with thin tumors and an S-phase fraction of < 10%. However, due to the small number of survivors, the latter observation should be further tested in a larger scale series.