Salivary duct carcinoma (cribriform salivary carcinoma of the excretory ducts [CSCED]) is an uncommon malignant tumor which occurs predominantly in men (83% in this series; mean age, 61 years) and most often in the parotid gland (92% in this series). The outcome is unfavorable for most patients; of 11 of 12 patients with follow-up, 45% had local recurrence, 54% had distant metastasis, and 45% were dead of disease within 10 years of diagnosis (mean, 3 years). Metastases to lymph nodes were common (72%). Immunohistochemical studies on paraffin-embedded tissue revealed that most tumors reacted with antibodies known to mark adenocarcinoma: B72.3 (11 of 11) and Lewis Y (ten of ten). High and low molecular weight cytokeratins were present in most tumors (nine of ten and seven of nine cases, respectively), supporting the concept that these adenocarcinomas were of ductal origin. Parotid ducts adjacent to CSCED expressed B72.3 in six of nine cases studied, but parotid ducts from normal tissue (adjacent to benign mixed tumors or enlarged periparotid lymph nodes) rarely expressed this marker (one of 17 cases). The detection of B72.3 diffusely in parotid ducts, especially those with atypia, may imply the presence of malignant tumor nearby, which could be useful in evaluating limited tissue from the parotid. However, further studies are necessary to confirm the significance of this finding.

The expression of tumor‐associated glycoprotein (TAG‐72), an oncofetal mucin‐like tumor‐associated glycoprotein derived from membrane‐enriched fractions of metastatyic breast carcinoma, has been detected by monoclonal antibody (MoAb) B72.3 in adenocarcinomas of breast, colon, lung, endometrium, pancreas, and ovary. The authors reported the scope of TAG‐72 expression detected by MoAb B72.3 in salivary neoplasia. They examined 96 salivary lesions (53 malignant and 37 benign primary tumors, 2 metastatic carcinomas, and 4 other benign lesions) and 17 normal tissues from parotid glands and found: diffuse TAG‐72 expression in 29 of 55 (53%) malignant tumors and 6 of 36 (17%) benign tumors and in no normal tissue; focal TAG‐72 expression in 10 of 55 (17%) malignant salivary tumors, 10 of 37 (25%) benign salivary tumors (all benign mixed tumors), and 1 of 17 (6%) histologically normal parotid gland ducts. Any expression of TAG‐72, whether diffuse or focal, was found to have a 71% sensitivity for detecting salivary malignant tumors, but an unacceptably low specificity for malignant lesions (57%). Alternatively, if only diffuse TAG‐72 expression was regarded as indicative of malignancy, the specificity of diffuse TAG‐72 expression was 86%, but sensitivity of detection decreased to 53%. The authors studied a subset of benign and malignant mixed tumors (BMT and MMT) and found that 12 of 15 (80%) MMT diffusely and strongly expressed TAG‐72, 2 of 15 MMT (13%) expressed TAG‐72 focally, and 1 MMT (7%) was nonreactive. By contrast, most BMT did not express TAG‐72; only sparse, focal TAG‐72 expression was seen in 10 of 27 (37%) BMT. If diffuse TAG‐72 expression is considered indicative of malignancy, its sensitivity and specificity for malignant mixed tumors is 80% and 100%, respectively. The authors suggest that diffuse TAG‐72 expression may resolve conflicts in determining whether or not a mixed tumor is malignant.

We analyzed the DNA ploidy and the nuclear size of hepatocytes within hepatocellular carcinoma, putative preneoplastic (clear cell and basophilic foci) and adjacent non-neoplastic liver in 30 woodchucks neonatally infected with the woodchuck hepatitis virus. In livers from control woodchucks, in clear cell foci and in most chronic portal hepatitis, the hepatocytes were diploid, with less than 10% tetraploid cells. Aneuploid peaks were found in 50% of the livers with chronic active hepatitis, in 63% of basophilic foci and in 90% of hepatocellular carcinoma. Within the same tumor, aneuploid peaks with different DNA indices were observed frequently, indicating heterogeneity of tumor. S-phase was always elevated, indicating an increased rate of proliferation. Aneuploid cells had nuclei that were larger than those of control liver cells. In some basophilic foci and in some livers with chronic active hepatitis, abnormal DNA was demonstrated before the development of hepatocellular carcinoma, suggesting that these may be populations of hepatocytes at risk of neoplastic transformation. (HEPATOLOGY 1994;20:21-29.)Woodchucks may be infected with the woodchuck hepatitis virus (WHV) that causes chronic hepatitis and hepatocellular carcinomas (HCC) without cirrhosis (1,2). Certain lesions such as basophilic or hyperplastic nodules, clear cell foci and nodules have been described associated with or preceding HCC (3-6), but little is known about the evolution of these lesions. 31/1/66809Foci of altered hepatocytes appear during hepatocarcinogenesis induced by chemicals and they have been considered precursors of carcinomas based on morphological, enzymatic and biochemical studies (7-11). These foci may display abnormal DNA content (12, 13) and may constitute a cell population at risk of neoplastic progression. Little is known, however, regarding the biological behavior of altered hepatocellular foci observed during viral hepatocarcinogenesis. A recent report indicates that focal enzymatic alterations emerging in WHVinfected woodchucks may be closely linked to neoplastic transformation of hepatocytes (14).DNA ploidy studies have become an important method in cancer research. They can provide valuable information and be useful in assessing tumor aggressiveness and prognosis ( 15-2 1).To better understand the biological characteristics of the putative preneoplastic and neoplastic lesions in viral hepatocarcinogenesis, we have analyzed by image analysis and flow cytometry the DNA ploidy and the nuclear size of the putative preneoplastic lesions and of HCC of woodchucks experimentally infected with WHV injection. MATERIALS AND METHODSThirty-seven formalin-fixed, paraffin-embedded liver biopsy blocks from 30 woodchucks were obtained from the New York State College of Veterinary Medicine, Ithaca, New York. These woodchucks had been inoculated subcutaneously during the first 3 days of life with 100 p,l of a 10-dilution of the WH7-PI pool infected with WHV. Woodchuck hepatitis surface antigen (WHsAg) and antibodies were detected in the...