Collecting-duct carcinoma of the kidney with prominent signet ring cell features.

We report a case in a 74-year-old woman of collecting-duct carcinoma of the kidney with prominent signet ring cell features. Grossly, the tumor measured 5.5 cm in greatest dimension, occupied the entire upper pole of the kidney, and was well circumscribed. Microscopically, it displayed a predominant tubulopapillary pattern of growth with a hyalinizing stroma. The tumor tubules were lined by a single layer of cells with large, pleomorphic nuclei, some of which had a hobnail appearance. Large intracytoplasmic vacuoles with compression of nuclei (signet ring cells) were present throughout the tumor. Alcian blue, mucicarmine, and periodic acid-Schiff stains failed to identify intracellular mucin or glycogen in the signet ring cells. Enlarged cells with intracytoplasmic vacuoles were also noted in the adjacent collecting ducts. The tumor cells were immunohistochemically positive for cytokeratin including cytokeratin 7, CAM 5.2, AE1/3, and 34 beta E12, vimentin, peanut lectin agglutinin, and Ulex europaeus agglutinin. Electron microscopy revealed that the intracytoplasmic vacuoles were due to intracellular edema. To the best of our knowledge, this is the first reported case of renal collecting-duct carcinoma with prominent signet ring cell features.

Colorectal cancer recurrence during pregnancy--unique and poorly understood clinical entity: report of a case.

The detection of primary or recurrent colorectal cancer during pregnancy is a rare event. Early diagnosis is difficult, because symptoms are often attributed to pregnancy. Here we describe a case of recurrent adenocarcinoma of the colon in a 23-year-old pregnant patient. The relationship between various hormonal and immunological changes of pregnancy and colorectal cancer is discussed.

Percutaneous large-core biopsy of papillary breast lesions.

OBJECTIVE: This study was undertaken to assess the accuracy of percutaneous large-core biopsy in evaluating papillary breast lesions. MATERIALS AND METHODS: A retrospective review of imaging-guided large-core breast biopsy of 1077 consecutive lesions revealed that papillary lesions were diagnosed in 34 (3%) cases. Surgical correlation (n = 22) or minimum 2 years' mammographic follow-up (n = 4) were available for 26 papillary lesions. Mammographic and histologic findings in these 26 cases were reviewed. RESULTS: Percutaneous biopsy histology had benign findings in nine lesions, atypical in 10, and malignant in seven. Of seven lesions yielding benign papilloma at percutaneous biopsy, none (0%) had carcinoma at surgery or mammographic follow-up. Surgery revealed carcinoma in one of two lesions yielding papillomatosis at percutaneous biopsy. This lesion was a spiculated mass; surgical biopsy, recommended because of mammographic-histologic discordance, revealed a radial sclerosing lesion and ductal carcinoma in situ (DCIS). Of 10 papillary lesions with atypical ductal hyperplasia at percutaneous biopsy, surgery revealed DCIS in three (30%). Of seven lesions in which percutaneous biopsy yielded papillary DCIS, surgery revealed DCIS in all seven; three (43%) also had invasive carcinoma. CONCLUSION: Among our patients, diagnosis by percutaneous core biopsy of benign papillary lesions proved to be accurate when concordant with imaging findings. Surgical excision was indicated when diagnosis by percutaneous biopsy revealed atypical papillary lesions or papillary DCIS. A larger series with longer follow-up is required to assess the clinical course of benign papillary lesions without atypia that are not excised after percutaneous large-core breast biopsy.