The role of sentinel lymph node mapping in staging of colon and rectal cancer.

PURPOSE: Nodal metastasis is the best predictor of survival for patients with colon cancer. Statistical models based on random distribution of positive lymph nodes suggest that to correctly classify nodal status with 95 percent confidence, 20 nodes are needed for T1 lesions, 17 nodes for T2, and 15 nodes for T3. The mean number of nodes identified in American patients is 8, suggesting that they might not be accurately staged. Patients in our tumor registry staged as "node-negative" had a short survival when they had < or =10 lymph nodes evaluated when compared with patients with >10 lymph nodes evaluated (p < 0.01). We hypothesized that the use of sentinel lymph node may assist in the staging of colon cancer. METHODS: Thirty-eight consecutive patients with colon lesions were prospectively enrolled into this trial between February 1998 and November 1999. Thirty-one patients met criteria for analysis. During surgery, Lymphazurin blue dye was injected subserosally into the area around the tumor. Routine nodal evaluation, with extra cuts of all sentinel nodes, was undertaken. RESULTS: At least one sentinel lymph node was found in 18 of 31 patients (58 percent). Sensitivity of 67 percent, specificity and positive predictive value of 100 percent, and negative predictive value of 94 percent were found when sentinel lymph nodes were identified. In 2 of these 18 patients, the sentinel lymph node was the only positive lymph node found. CONCLUSIONS: Application of the sentinel lymph node technique to colon cancer may make it easier to identify lymph nodes most likely to contain metastatic disease, potentially "down-staging" more patients. This may have implications in postoperative care.

Analysis of cathepsin D in human breast cancer: usefulness of the processed 31 kDa active form of the enzyme as a prognostic indicator in node-negative and node-positive patients.

The relative amounts of the precursor (52 kDa) and processed (31,27 kDa) forms of cathepsin D have been analyzed by Western blotting in biopsied breast tissue cytosols from 134 lesions from invasive breast cancer patients, 24 lesions from patients with ductal carcinoma in situ (DCIS), 227 lesions from benign breast disease patients, and 28 lesions from normal control subjects. The mean relative percentage amount of the 31 kDa form was significantly increased (p < 0.001) in the invasive breast cancer group compared to the other three groups. In addition, the mean relative percentage amount of the 31 kDa form was significantly increased (p < 0.05) in node-positive compared to node-negative breast cancer patients. In the benign breast disease group, patients with proliferative-type disease had a significantly increased (p = 0.02) mean relative percentage amount of the 31 kDa form of cathepsin D compared to patients with nonproliferative-type disease. Invasive breast cancer patients were followed for up to 75 months to determine if the relative percentage amount of the 31 kDa form of cathepsin D was predictive of disease-free and overall survival. Although the amount of the 31 kDa form was not predictive of disease-free survival, patients in the 'high' 31 kDa group (> 18%) were significantly (p < 0.05) more likely to die than patients in the 'low' 31 kDa group (< or = 18%). The 12 patients who died were all node-positive and in the high 31 kDa group. It thus appears that the relative amount of the processed, active 31 kDa form of cathepsin D is a useful prognostic indicator, at least in node-positive breast cancer patients.

Biliary CA 19-9 values correlate with the risk of hepatic metastases in patients with adenocarcinoma of the pancreas.

Serum values of the tumor-associated antigen CA 19-9 are useful as an independent predictor of survival in patients with adenocarcinoma of the pancreas. However, the utility of biliary CA 19-9 values is unknown. This study was undertaken to determine whether biliary CA 19-9 levels are predictive of hepatic metastases. Between 1991 and 1996, thirty-eight patients treated for adenocarcinoma of the pancreas were evaluated using a biliary CA 19-9 assay. Bile was obtained from percutaneous stents placed during the perioperative period. Five of the 38 patients had low serum levels of CA 19-9 (<2 U/ml) and were excluded from the study. Twenty-seven (80%) of the 33 patients developed distant metastases: five pulmonary, five peritoneal, and 17 hepatic. Liver metastases were discovered initially in 10 and after resection of the primary tumor in seven (median interval 10 months). Biliary CA 19-9 values were significantly higher in patients with hepatic metastases (median 267, 400 U/ml; range 34,379 to 5,000,000 U/ml) compared to patients without metastatic disease (median 34,103 U/ml; range 6,620 to 239, 880 U/ml; P <0.006). Patients with hepatic, peritoneal, and pulmonary metastases had median survivals of 8,14, and 35 months, respectively (P <0.0041). All patients without metastatic disease are alive (median follow-up 13 months). Biliary CA 19-9 values are associated with a stepwise increase in the risk of developing metastatic disease. Patients with biliary CA 19-9 levels greater than 149,490 U/ml have an increased risk of developing recurrent disease in the liver and may warrant further hepatic evaluation or therapy.

Comparison of bax, waf1, and IMP dehydrogenase regulation in response to wild-type p53 expression under normal growth conditions.

Recently, we demonstrated that downregulation of inosine-5'-monophosphate dehydrogenase (IMPD; IMP:NAD oxidoreductase, EC 1.2.1.14), the rate-limiting enzyme for guanine nucleotide biosynthesis, is required for p53-dependent growth suppression. These studies were performed with cell lines derived from immortal, nontumorigenic fibroblasts that express wild-type p53 conditionally by virtue of a metal-responsive promoter. Here, the p53-dependent properties of the original "p53-inducible" fibroblasts are presented in detail and compared to related properties of epithelial cells that also express wild-type p53 conditionally, but by virtue of a temperature-responsive promoter. Both types of p53-inducible cells were designed to approximate normal physiologic relationships between the host cell and the regulated p53 protein. Together, they were used to investigate expression relationships between IMPD and other p53-responsive genes proposed as mediators of p53-dependent growth suppression. In both types of cells, IMPD activity, protein, and mRNA were consistently coordinately reduced in response to p53 expression. In contrast, mRNAs for waf1, bax, and mdm2 showed disparate patterns of expression, being induced in one conditional cell type, but not the other. This distinction in regulation pattern suggests that under normal growth conditions, unlike IMPD downregulation, bax and waf1 induction is not a rate-determining event for p53-dependent growth suppression.

Prediction of recurrence and survival by post-resection CA 19-9 values in patients with adenocarcinoma of the pancreas.

BACKGROUND: CA 19-9 levels are useful for the diagnosis of patients with pancreatic adenocarcinoma. However, interest has recently turned toward its use as a prognostic indicator. The purpose of this study is to determine whether postoperative CA 19-9 levels predict disease-free survival (DFS) and median survival (MS) in patients after resection. METHODS: Between 1988 and 1996, 40 patients underwent resection for pancreatic adenocarcinoma and were evaluated with postoperative CA 19-9 assays. Eight patients had low preoperative levels of CA 19-9 (< 2) and were excluded. RESULTS: CA 19-9 levels are good predictors of DFS and MS. Patients whose postoperative CA 19-9 values normalized by 3 to 6 months (< 37 U/ml) had longer DFS (24 vs. 10 months, p < 0.04) and MS (34 vs. 13 months, p < 0.04). Patients with postoperative CA 19-9 values less than 180 U/ml at 1 to 3 months had a similar DFS (19 vs. 5 months, p < 0.0009) and MS (34 vs. 13 months, p < 0.0001) compared to patients with normal values at 3 to 6 months. CONCLUSIONS: Postoperative measurements of CA 19-9 were the best predictors of DFS and MS. Values < 180 U/ml at 3 months were as predictive as normal values by 3 to 6 months postoperatively. Consequently, CA 19-9 levels should be obtained for use as a stratification parameter in phase III trials.

Humoral modulation of lymphokine-activated killer (LAK)-cell induction in humans: IgG-related and non-IgG inhibitors in sera from cancer patients.

Soluble inhibitors of lymphokine-activated killer (LAK) cell induction were characterized and purified from serous fluids from healthy donors or from patients with advanced cancer. Inhibitory activity in sera from cancer patients was partially absorbed with protein A agarose or anti-human IgG agarose. Following absorption, residual inhibition varied with individual sera, suggesting the presence of IgG-related and non-IgG inhibitory factors, and the proportions varied in the patient population. IgG, purified by affinity chromatography from ascitic fluids, from plasma of cancer patients, and from plasma of healthy donors, significantly inhibited IL-2 induction of LAK cells in a dose-dependent manner. Irrespective of the sources, inhibitory activity resided in the high-molecular-weight IgG fraction composed of IgG aggregates and immune complexes, but not monomeric IgG. Commercially prepared human IgG in aggregated form, but not in monomeric form, inhibited LAK cell induction in a dose-dependent manner. In contrast, neither bovine IgG nor human albumin affected LAK cell induction, even at higher concentrations. Aggregated human IgG inhibited LAK cell induction in unfractionated peripheral blood mononuclear cells (PBMC) but not in monocyte-depleted peripheral blood lymphocytes (PBL). Despite extensive (greater than 99%) depletion of IgG by protein-G affinity chromatography, the serous fluid from cancer patients displayed significant inhibitory activity. Fractionation of the IgG-depleted inhibitory materials by Sephacryl S-300, high-pressure ion-exchange column (HPIEC) or gel-permeation chromatography (HPGPC) demonstrated a 65-kDa inhibitor, distinct from IgG. Affigel-blue affinity chromatography of the 65-kDa fraction depleted albumin but did not remove the inhibitory activity, suggesting that the 65-kDa inhibitor is not serum albumin nor an albumin-bound component. These results suggest that serous fluids from patients with advanced-stage cancer contain 2 distinct regulators for LAK cell induction: (I) aggregated IgG and (2) a 65-kDa inhibitor, distinct from albumin.

Patterns of human tumor-infiltrating lymphocytes in 120 human cancers.

Tumor-infiltrating lymphocytes from 120 samples of human cancers, including melanoma, renal cell carcinoma, breast cancer, sarcoma, and colon cancer, were examined. The percentage of lymphocytes recovered from the cancer varied widely; that of renal cell carcinoma was higher than that of breast or colon cancer (65% vs 45%), which was higher than that of melanomas or sarcomas (30% to 35%). The types of lymphocytes before and after interleukin 2 activation showed specific patterns. CD4+ helper T cells predominated in all tumors except melanomas, which had more CD8+ cytotoxic T cells. CD16+ natural killer cells were recovered in renal cell carcinoma and sarcomas. Three different cytotoxic lymphocytes were identified among interleukin 2-activated tumor-infiltrating lymphocytes: (1) CD3+ CD16- cytotoxic T lymphocytes with cytotoxicity restricted to autologous tumor cells in melanomas, (2) CD3-CD16+ natural killer cells with vigorous major histocompatibility complex-nonrestricted cytotoxicity in renal cell carcinoma, and (3) CD3+ CD16- T cells with modest levels of major histocompatibility complex-nonstricted cytotoxicity in all cancers except melanomas. Thus, there was considerable diversity of tumor-infiltrating lymphocytes among these histologically distinct tumors with respect to magnitude of lymphocyte infiltration, phenotypic expression, and functional capacity.

Biochemical characterization of 1-butanol-extracted murine tumor-specific transplantation antigens.

This investigation sought to characterize biochemically the tumor-specific transplantation antigens (TSTA) expressed on the cell surface of a panel of chemically induced fibrosarcomas of C3H/HeJ mice. Results suggest a uniform antigenic framework upon which individual specificities are superimposed. The antigens expressed by the 3-methylcholanthrene-induced fibrosarcomas MCA-D, MCA-F, and MCA-2A fulfill the requirements of a TSTA; namely, immunization of syngeneic hosts with irradiated cells or soluble extracts engenders a tumor-specific immune response such that animals resist challenge with the same, but not another, tumor. Brief incubation of intact tumor cells in single-phase aqueous solutions of 2.5% (v/v) 1-butanol extracts an immunoprotective TSTA, but not alloantigenic activity, from MCA-F cells. This extraction protocol was extended to the two other MCA-induced neoplasms. The butanol-extracted TSTA from the three tumors displayed isoelectric pHs of 6.4 to 6.6 following preparative isoelectric focusing. The tumor-specific immunoprotective activity from all three tumors displayed an apparent molecular weight of 150,000 (150 kDa) during high-performance gel permeation chromatography. The chromatographic properties of the 150 kDa antigens were unaffected by reduction using dithiothreitol, but incubation in acetate buffer, pH 3.0, dissociated the 150 kDa complex into at least two components with molecular weights of 70 to 100 kDa and 20 to 40 kDa. Only the smaller component displayed TSTA activity. The presence of two major components in the 150-kDa antigen was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. TSTA activity was sensitive to digestion with pronase, papain, chymotrypsin, and alpha-mannosidase, but resistant to DNase, RNase, neuraminidase, trypsin, endoglycosidase H, and a mixed-function glycosidase. In addition, the TSTA activity was unaffected by heating. These data demonstrate that MCA carcinogenesis results in the expression of immunologically unique epitopes on biochemically related glycoproteins and suggest a unified mechanism for the generation of TSTA polymorphism.

Determination of palladium, platinum and rhodium in geologic materials by fire assay and emission spectrography.

A method is described for the determination of palladium down to 4ppb (parts per billion, 10(9)), platinum down to 10 ppb and rhodium down to 5 ppb in 15 g of sample. Fire-assay techniques are used to preconcentrate the platinum metals into a gold bead, then the bead is dissolved in aqua regia and diluted to volume with 1M hydrochloric acid. The solution is analysed by optical emission spectrography of the residue from 200 mul of it evaporated on a pair of flat-top graphite electrodes. This method requires much less sample handling than most published methods for these elements. Data are presented for G-1, W-1, and six new standard rocks of the U.S. Geological Survey. The values for palladium in W-1 are in reasonable agreement with previously published data.