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K Sheahan
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Exterminating the year 2000 bug.
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Noncirrhotic hepatoma presenting with paraneoplastic neurologic manifestations: two cases.
Hepatocellular carcinoma usually occurs in patients with cirrhosis and is rarely associated with paraneoplastic neurologic disorders. We describe two young patients with hepatomas occurring in noncirrhotic livers, both of whom presented with neurologic symptoms. A 19-yr-old man who presented with coma and a 23-yr-old woman with a 3-month history of progressive hemiparesis, dysarthria, and altered affect were each found, at autopsy, to have hepatocellular carcinoma occurring in a noncirrhotic liver. Neuropathologic examinations revealed widespread multifocal necrotizing leukoencephalopathy in the man and occlusive noninflammatory cerebral vasculopathy with widespread cortical and subcortical infarcts in the woman. It is unlikely that the neuropathologic findings in these patients are explicable on the basis of antibody-mediated tissue injury.
Urokinase-type plasminogen activator in colorectal cancer: relationship with clinicopathological features and patient outcome.
Urokinase-type plasminogen activator (u-PA) is a serine protease that has been implicated in cancer invasion and metastasis. We quantitated u-PA levels in normal colorectal mucosa, adenomatous polyps, and colorectal cancers and correlated these levels with clinicopathological features and patient survival. Detergent extracts were prepared from 133 colorectal cancers, 133 corresponding colorectal mucosal samples, and 15 synchronous adenomatous polyps. u-PA levels were determined using an ELISA, and a cancer:normal u-PA ratio was calculated for each case. u-PA levels were higher in cancers than in normal tissues, whereas adenomas had intermediate levels (P < 0.0001). u-PA levels were unrelated to clinical or pathological features. Survival was decreased in patients with a high cancer:normal u-PA ratio (P = 0.007). Multivariate survival analysis of patients undergoing curative surgery confirmed that the u-PA cancer:normal ratio was related to outcome (relative risk, 2.67; P = 0.02) and was independent of tumor stage (relative risk, 2.26; P = 0.03). Our study suggests that a high ratio of cancer to normal mucosal u-PA indicates an increased risk of colorectal cancer progression. Measurement of u-PA may provide useful prognostic information in patients undergoing curative surgery for colorectal cancer. The aggressive behavior of colorectal cancers with a high u-PA ratio suggests that the protease might be a suitable target for the development of therapeutic agents to prevent invasion and metastasis.
Prognostic significance of p53 abnormalities in colorectal carcinoma detected by PCR-SSCP and immunohistochemical analysis.
Abnormalities in the p53 tumour suppressor gene and in the expression of its protein are common in colorectal carcinoma. The prognostic significance of these p53 abnormalities was studied in 66 patients with colorectal cancer, followed for more than 10 years. Single-strand conformation polymorphism (SSCP) analysis was used to detect alterations in exons 5-8 of the p53 gene. Paraffin sections were examined immunohistochemically for p53 overexpression with the monoclonal antibody DO-7 (Dako) both with and without microwave antigen retrieval. Abnormalities of the p53 gene were found in 41 per cent of cases by SSCP analysis. Outcome was unrelated to SSCP abnormalities (P = 0.19), except for the Dukes' A and B subgroup, where decreased survival was found in cases with abnormal SSCP (P = 0.01). Overexpression of p53 protein was seen by immunohistochemistry in 47 per cent of cases without, and in 52 per cent of cases with microwave antigen retrieval. Immunohistochemical overexpression of p53 protein either with or without microwave antigen retrieval was an independent prognostic indicator of poor survival. These results suggest that for routine purposes, immunohistochemical detection of the p53 protein product may be more useful than SSCP analysis of the encoding p53 gene in identifying those at high risk of colorectal cancer recurrence and death.
Pathological evidence in support of total mesorectal excision in the management of rectal cancer.
Some 50 total mesorectal excision specimens were examined following rectal excision for cancer. Circumferential margin involvement was rare, but mesorectal tumour deposits were present in 17 of 44 patients with pT3 tumours, and 23 of 44 had mesorectal nodal involvement. No patient with a pT2 tumour had mesorectal involvement. Failure to excise the mesorectum completely has the potential to leave gross or microscopic residual disease that may in theory predispose to local failure. Total mesorectal excision is necessary to avoid incomplete pathological evaluation of the mesorectum and understaging of rectal cancer.
Aggressive thyroid cancer associated with toxic nodular goitre.
Reports of concurrent thyrotoxicosis and thyroid cancer have appeared in the last three decades. While most of the tumours have been clinically inconsequential, it has been suggested that thyroid carcinomas arising in patients with Graves' disease tend to behave aggressively, while those associated with toxic nodular goitre follow a more benign course. We report a contrary clinical experience with four cases of thyrotoxicosis associated with metastatic thyroid cancer, two of which were fatal. All four patients had toxic nodular goitre. Thyroid eye signs were uniformly absent. Two patients had received 131I therapy; none had other history of irradiation to the head or neck. Antimicrosomal and antithyroglobulin antibodies were absent in all four patients. Thyroid-simulating immunoglobulin, which was measured in one patient, was also absent. Histopathological examination of the resected thyroid glands revealed two papillary cancers. one mixed anaplastic/papillary and one anaplastic cancer. All four patients had cervical node involvement and one had pulmonary metastases. Both patients with anaplastic carcinoma succumbed to their disease within 6 months: neither of the patients with papillary cancer had disease recurrence after 2 and 4 years, respectively. The experience reported here of aggressive thyroid cancer associated with toxic nodular goitre may represent coincidence or, alternatively, it may represent the early recognition of a change in the natural history of toxic nodular goitre.
Urokinase-type plasminogen activator and outcome in Dukes' B colorectal cancer.
Urokinase-type plasminogen activator (u-PA) is a serine protease involved in cancer metastasis. Using immunohistochemical methods, we examined the relation between u-PA and long-term survival in 70 patients with Dukes' B colorectal cancer. 8-year survival was 81% in patients whose tumours demonstrated low-grade epithelial u-PA staining and 43% in those with high-grade staining (log-rank test, p = 0.01). Survival was unrelated to stromal u-PA staining. These results suggest that u-PA may be useful in the identification of patients with non-metastatic colorectal cancer at risk of tumour recurrence.
Human cathepsin B-encoding cDNAs: sequence variations in the 3'-untranslated region.
We have isolated two cathepsin B (CTSB)-encoding cDNAs, hCBF1 and hCBF2, from a normal human embryonic fibroblast library. These clones demonstrate 98% identity to overlapping regions of published human hepatoma and kidney CTSB cDNAs, but show some interesting differences from the published sequences in the 3'-untranslated region (3'-UTR). Both hCBF1 and hCBF2 contain a 10-bp insertion in the 3'-UTR that may permit formation of a highly stable stem-loop structure not present in mRNAs without this insertion. Our hCBF1 cDNA also contains a 1019-bp extension of the 3'-UTR sequence that resembles the long 3'-UTR reported for murine CTSB cDNAs. Probes unique to this 3'-UTR extension hybridize to 4.0- and 1.7-kb CTSB RNAs on Northern blots, but not to the major 2.2-kb mRNA transcript. Our data reveal variations in normal human CTSB transcripts that result from differences in the length of the 3'-UTR, as well as the presence or absence of a stem-loop stabilizing sequence.
Soft tissue and visceral sarcomas in Irish patients. Interim analysis of data obtained by the Dublin Soft Tissue Tumour Panel.
The Dublin Soft Tissue Sarcoma Panel was established in 1989 with a view to achieving a unified approach to diagnosis and management of soft tissue and visceral sarcomas. This interim report presents data on 265 prospectively-evaluated patients and on a separate retrospective series of 126 patients. The patients in the prospective series were treated by 93 different surgical and medical specialists. Tumours presented in all anatomic sites and ranged in size from 0.2 to 60 cm. Leiomyosarcoma was the commonest tumour type. Eighty-nine tumours were inoperable at clinical presentation. There was a consensus panel diagnosis in over 90%, non-neoplastic reactive lesions and primitive round cell tumours being the most difficult cases diagnostically. Management, including onward referral for chemotherapy or radiation therapy, was inconsistent. The 2-year survival figures were: 43% (1989-91) and 37% (1980-88). These findings should provide a basis for the evaluation of coherent treatment strategies for Irish sarcoma patients.
Metastatic adenocarcinoma of an unknown primary site. A comparison of the relative contributions of morphology, minimal essential clinical data and CEA immunostaining status.
Measurement of the relative contributions of morphology alone; minimal essential clinical data; immunohistologic reactivity of a prototypic tumor marker, carcinoembryonic antigen (CEA); and the process by which a pathologist can identify the origin of a metastatic adenocarcinoma of unknown primary site is the subject of this report. To standardize the case material, we used an image digitizing and archival system to present 100 metastatic adenocarcinomas of known primary site as unknowns to two pathologists. The images were selected to show only gland-forming areas of the carcinomas and excluded all normal tissue elements. They were viewed, initially without, and then with, identification of gender and metastatic site. Subsequently, the results of immunoperoxidase staining for CEA, assessed independently by a third pathologist, were provided. Our analysis showed that, overall, the correct primary site was chosen as choice 1, 2, or 3 in 72% and 76%, and as choice 1 in 49% and 47% of cases, respectively. Accuracy was highest for prostatic, ovarian, and breast carcinomas, and lowest for upper-gastrointestinal tract, biliary tract, and pancreatic adenocarcinoma. Statistical analysis showed the largest increments in accuracy in the choice 1 prediction in each tumor category were achieved by provision of minimal essential clinical data. Knowledge of CEA status did not affect overall accuracy; however, it increased the odds of making the correct diagnosis for ovarian, colorectal, and endometrial (both pathologists) carcinomas, and for prostatic, pulmonary and esophago-gastric adenocarcinomas (one pathologist). The study exemplifies a model for the objective measurement of the contribution of ancillary studies, such as immunoperoxidase markers, to the accuracy of pathologic diagnosis.
Cytogenetic studies of an adrenal cortical carcinoma.
Cytogenetic findings in the third reported case of adrenal cortical carcinoma are described. In contrast to the two previous cases, hypodiploidy characterized almost all cells, which had as many as eight abnormal chromosomes in each cell analyzed.
Analysis of epithelial and lymphoid phenotypic markers in relation to growth pattern of colorectal adenomas.
The relationship of villous to tubular adenomas is poorly understood and often difficult to characterize morphologically. A villous growth pattern in colorectal adenomas has been associated with a higher frequency of high-grade dysplasia. We compared phenotypic markers using immunoperoxidase techniques in paired samples of villous (75% to 100% villous) and pure tubular adenomas matched for size and degree of dysplasia, which were selected by review of 1,000 polyps from our files. The following monoclonal antibodies were used: CAM 5.2 and AE1/AE3 to cytokeratins; B18, D14, B7.1, and B7.8 to four distinct carcinoembryonic antigen epitopes; Leu-M1 and LN3 to HLA-DR antigen; LN2 to invariant chain class II major histocompatibility complex; LN1 and MB2 to B-cell markers; UCHL1 and MT1 to T-cell markers; Leu-7 to natural killer cells; Mac 387 to macrophages; S-100 to Langerhans-type cells; and a polyclonal antibody to secretory component. LN3 reactivity correlated with villous morphology and secretory component correlated with tubular morphology. Combined HLA-DR and secretory component expression discriminated between tubular and villous growth patterns in 12 of 15 pairs of adenomas (P less than .001). LN2 was expressed more frequently than LN3, but did not correlate with growth pattern. Neuroendocrine cells (Leu-7) were more frequent in tubular adenomas. Carcinoembryonic antigen epitopes did not relate to growth pattern. We did not confirm previously reported differences in cytokeratin expression. We concluded that among the markers tested, HLA-DR expression, which may have an immunologic basis, is most characteristic of colorectal adenomas that exhibit a villous growth pattern.
Immunohistochemical analysis of small cell tumors of the thyroid gland: an Eastern Cooperative Oncology Group study.
The majority of small cell anaplastic tumors of the thyroid gland are generally believed to be non-Hodgkin's lymphomas, including most of those formerly classified as small cell carcinomas. Using a panel of antibodies capable of detecting epithelial, neuroendocrine, and B and T cells in paraffin-embedded tissue sections, we studied 68 thyroid neoplasms in which the original diagnosis was small cell carcinoma or lymphoma. Sixty-three of the tumors were identified as lymphomas of B-cell origin on the basis of L26 reactivity used in conjunction with light chain restriction and MB2 immunostaining. Two additional tumors were classified as lymphomas of indeterminate phenotype. Immunophenotyping indicated an epithelial origin in the remaining three tumors. No cases of medullary carcinoma were detected by immunostaining. Histologic review revealed a predominance of large cell and immunoblastic lymphomas, with low-grade lymphomas of mucosa-associated lymphoid tissue histology accounting for only five cases. Our findings indicate that the majority of small cell anaplastic tumors of the thyroid are B-cell lymphomas. Although primary small cell carcinoma of the thyroid may rarely occur, this diagnosis should not be made without immunohistologic confirmation.
Cysteine endopeptidase activity levels in normal human tissues, colorectal adenomas and carcinomas.
We have assayed cysteine endopeptidase activities in 17 types of normal human tissue and in matched sets of colorectal mucosa, adenoma and carcinoma samples. Our data indicate that cathepsin B enzyme levels vary 70-fold and cathepsin L enzyme levels vary 20-fold from one normal tissue to another. Cathepsin B specific activity in normal tissues fell into 3 categories. High activity, with a mean of 156.7 +/- 41.5 nmoles min-1 mg-1 protein, was measured in liver, thyroid, kidney and spleen; intermediate activity, with a mean of 60.2 +/- 8.3 nmoles min-1 mg-1 protein, was measured in heart, colon, adrenal and lung; and low activity, with a mean of 18.4 +/- 9.7 nmoles min-1 mg-1 protein, was measured in prostate, testis, nerve, stomach, pancreas, brain, skeletal muscle, skin and breast. Cathepsin L specific activity fell into 2 categories. High activity, with a mean of 51.1 +/- 4.9 nmoles min-1 mg-1 protein, was measured in thyroid, liver and kidney; and low activity, with a mean of 11.4 +/- 5.5 nmoles min-1 mg-1 protein, was measured in spleen, colon, heart, adrenal, lung, testis, brain, nerve, skin, stomach, pancreas, skeletal muscle, prostate and breast. Our characterization of these enzyme levels provides a reference standard for normal cathepsin B and L activities in human tissues that should enhance the detection of their deregulation in disease states. For example, in studies of colorectal carcinoma and normal mucosa, we observed a significant tumor-specific increase in cathepsin B and L activities with particularly high activity levels in earlier (Dukes' A and B) compared to later (Dukes' C and D) stages of colorectal cancer. In contrast, adenomas from colorectal cancer patients expressed normal levels of cathepsin B activity, providing evidence that the increase in expression of cathepsin B may be a sensitive marker for progression from the pre-malignant to the malignant state in the development of colorectal cancer.
Stage-specific increases in cathepsin B messenger RNA content in human colorectal carcinoma.
Cathepsin B mRNA levels and banding patterns were characterized in human colorectal mucosa and carcinoma tissues from patients with tumors of different Dukes' stages. Quantitation of mRNA content using slot blot hybridization demonstrated an increase in cathepsin B message in seven of eight tumor tissues with an average increase of 3.5-fold over patient-matched control mucosa samples. This tumor-specific increase in cathepsin B mRNA confirms and extends our previous observation that cathepsin B enzyme specific activity levels are significantly elevated in colorectal carcinomas. In fact, the increase in mRNA levels is greater and more consistent than the observed increase in enzyme activity, suggesting that posttranscriptional or posttranslational regulation of cathepsin B expression occurs in colorectal tumors. The mRNA data also support our earlier observation that cathepsin B enzyme activity levels are inversely correlated with Dukes' stage. The tumor-specific increase in cathepsin B mRNA content is almost 4 times greater in earlier stage (Dukes' A and B) tumors than in later stage (Dukes' C and D) tumors. Thus, increased cathepsin B gene expression is particularly characteristic of tumors which are in the process of invading the bowel wall or local tissues compared with tumors which have already spread to more distant sites. Northern blot data on cancer/normal pairs indicate that the increase in cathepsin B mRNA in colorectal carcinoma is due primarily to changes in the amount of the 2.2- and 4.0-kilobase transcripts which are seen in control tissue. However, low levels of two additional cathepsin B mRNA transcripts (1.5 and 3 kilobases in size) were also observed in tumor tissue.
Differential reactivities of carcinoembryonic antigen (CEA) and CEA-related monoclonal and polyclonal antibodies in common epithelial malignancies.
To evaluate the role of carcinoembryonic antigen (CEA) in solving problems of tumor histogenesis in surgical pathology, monoclonal antibodies to four distinct epitopes of CEA (E-Z-EM) were applied to paraffin sections of 303 epithelial neoplasms from multiple sites. Two epitopes were CEA specific (D14 and B7.1), one was shared with nonspecific cross-reacting antigen (NCA) (B7.8), and the fourth (B18) was common to CEA, NCA, and biliary glycoprotein antigen (BGP). A sample of the tumors (n = 110) was also stained with a polyclonal anti-CEA (DAKO). Gastrointestinal adenocarcinomas, including esophageal and gastric (n = 19), small intestinal (n = 8), colorectal (n = 56), biliary tract (n = 8), and pancreatic adenocarcinomas (n = 14), were consistently positive with all five antibodies. Other predominantly gland-forming carcinomas tested, comprising lung (n = 22), ovary (n = 18), and endometrium (n = 12), were either invariably negative with all five antibodies (endometrial adenocarcinoma, non-mucinous ovarian adenocarcinoma) or demonstrated selective and variable positivity (lung: D14, 50%; ovarian mucinous: D14, 50%). Among large polygonal cell carcinomas (hepatocellular carcinoma, renal cell carcinoma, melanoma, and adrenal carcinoma), only hepatomas stained positively, showing a distinctive canalicular staining pattern with the B18 (BGP epitope) (55%) and polyclonal antibody (50%). In the small polygonal cell carcinoma category, true CEA positivity was rare in breast (D14, 10% and B7.1, 14%) and never seen in prostatic carcinomas and carcinoid tumors. A subset of these breast (8 of 42), prostate (4 of 22), and carcinoids (4 of 7) showed exclusive positivity for the B18 antibody (NCA/BGP epitope). Ovarian serous papillary carcinomas (n = 14), papillary carcinomas of thyroid (n = 12), transitional cell carcinomas of the bladder (n = 11), and mesotheliomas (n = 3) were negative with all monoclonal antibodies. Metastatic carcinomas (n = 74) showed a similar pattern of reactivity to primary tumors. The authors conclude that CEA immunostaining may assist in identifying the histogenesis of epithelial tumors in several morphologic categories; that differential reactivities of the CEA monoclonal antibody panel exceed those of the polyclonal antibody; and that the discriminating power of the monoclonal panel is related to whether (1) CEA is or is not produced or (2) NCA or BGP is produced without concomitant CEA production. There is little evidence to support a concept of site-specific CEA species.
Anti-estradiol immunoperoxidase labeling of nuclei, not cytoplasm, in paraffin sections, determines estrogen receptor status of breast cancer.
We evaluated a commercially available polyclonal antibody to 17 beta-estradiol as the basis for an estrogen receptor (ER) assay of breast carcinoma in formalin-fixed paraffin tissues and then compared it with both the ER-ICA antibody in serial paraffin sections and the biochemical assay of corresponding fresh tissue. Using the estradiol antibody, 49 of 50 cases showed some cytoplasmic staining; 38 cases had nuclear staining. Sensitivity and specificity for different proportions of positive nuclear and cytoplasmic staining were calculated using receiver-operator characteristic curves. The optimum correlation with the biochemical assay was obtained with nuclear staining alone. Greater than 30% nuclear positivity as a cut-off point yielded a sensitivity of 76% and a specificity of 82%. The corresponding ER-ICA values in 38 cases yielded a sensitivity of 93% and a specificity of 56%. The methodology for the ER-ICA assay was more technically demanding in paraffin sections than that of the estradiol antibody and considerably more expensive. This study is the first to show that with nuclear staining only, and not cytoplasmic staining, as the parameter of positivity, the immunocytochemical assay of ER with anti-17 beta-estradiol antibody in routinely processed, formalin-fixed, archival material is an accurate and specific method for the determination of the ER status of breast carcinoma.