Squamous Cell Carcinoma of the Rectum: Report of Two Cases

Squamous cell carcinoma of the rectum is extremely rare. Herein we report two cases of rectal squamous cell carcinoma. Case 1 was a 44-year-old Korean female presenting with abdominal pain and rectal bleeding for 3 months before her hospital visit. A colonoscopic examination revealed an ulcerated rectal mass 8 cm proximal to the anal verge. Chemoradiotherapy was administered following Hartmann's procedure in case 1. The patient remained alive during 19 months of follow up. Case 2 was a 43-year-old Korean female who had severe constipation for 2 months. A barium enema and computed tomography of the pelvis showed a rectal mass adherent to the sacrum. Based on the results of a colonoscopic biopsy, a diverting colostomy was performed in case 2, with no further treatment. The pathologic findings showed that both tumors were composed of oval-shaped cells with abundant eosinophilic cytoplasm and intercellular bridges with keratin pearls, and thus were diagnosed as well-differentiated squamous cell carcinoma. Neither of the cases showed evidence of HPV infection. The pathogenesis of rectal squamous cell carcinoma has not been clarified. Herein we report two cases of rectal squamous cell carcinoma and briefly discuss the possible histogenesis.

Ovarian Endometrioid Adenocarcinoma with a Yolk Sac Tumor Component

Ovarian endometrioid adenocarcinoma (EAC) with a yolk sac tumor (YST) component is extremely rare. Only twelve cases have been reported in the English literature. We report here two additional cases of this rare tumor. The YST component showed classic microscopic features, and immunohistochemically stained positive for alpha-fetoprotein (AFP), but negative for cytokeratin 7 (CK7), epithelial membrane antigen (EMA), estrogen receptor (ER) and progesterone receptor (PR). The EAC appeared to blend into the YST in several areas and immunohistochemically stained positive for CK7, EMA, ER, and PR, but negative for AFP.