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Identification of pancreatic cancer in patients presenting with an enlarged pancreatic mass is a major diagnostic problem. Positron emission tomography (PET) using the radiolabeled glucose analogue 18F-fluorodeoxyglucose (FDG) has been suggested to provide excellent accuracy for noninvasive determination of suspicious pancreatic masses. We conducted a prospective study to verify these results. Forty-two patients admitted for pancreatic surgery underwent PET scanning. Image analysis was based on visual film evaluation and quantification of regional tracer uptake. PET imaging was visually analyzed by three observers blinded for the results of other diagnostic tests; they qualitatively graded the scans using a five-point scale (I = low to V = high) for the presence and intensity of focal FDG uptake. Diagnosis was proven by histology (n = 38) or follow-up (n = 4). Furthermore, the results of PET were compared with helical computed tomography (CT) and conventional ultrasonography (US), done during the routine diagnostic workup before pancreatic cancer surgery. Regarding only the results with scores of IV and V as positive for representing definite malignancy yielded a sensitivity of 71% and a specificity of 64% for film reading. Quantification of regional tracer uptake contributed no significant diagnostic advantage for differentiation between benign and malignant tumors. Helical CT revealed a sensitivity of 74% and a specificity of 45.5% and abdominal US 56% and 50%, respectively. We concluded that PET imaging provides only fair diagnostic accuracy (69%) for characterizing enlarged pancreatic masses. PET does not allow exclusion of malignant tumors. In doubtful cases, the method must be combined with other imaging modalities, such as helical CT. The results indicate that the number of invasive procedures is not significantly reduced by PET imaging.

Minimal residual disease in patients with operable pancreatic carcinoma is frequently missed by current noninvasive tumour staging. We applied an immunocytochemical cytokeratin assay that allows identification of individual pancreatic carcinoma cells disseminated to bone marrow. Prior to therapy, bone marrow was aspirated from the upper iliac crest of 48 patients with ductal adenocarcinoma of the pancreas at various disease stages and an age-matched control group of 33 noncarcinoma patients. Tumor cells in cytologic bone marrow preparations were detected with monoclonal antibodies (mAbs) CK2, KL1, and A45-B/B3 to epithelial cytokeratins (CK) using the alkaline phosphatase antialkaline phosphatase method. CK-positive cells were found in 14 (48.4%) of 31 cancer patients treated with curative intent and in 10 (58.8%) of 18 patients with extended disease. The overall frequency of these cells was 1 to 83 per 5x10(5) mononuclear cells with no significant differences between patients at different tumor stages and lymph node involvement. After a median follow-up of 22.8 months (range 3-48 months), 6 (40.0%) of 15 patients who underwent complete surgical resection but had tumor cells in bone marrow presented with distant metastasis and 7 (46.7%) had local relapse compared to none of 12 corresponding patients without such cells (p<0.05). Univariate survival analyses revealed that the presence of CK-positive cells was predictive of reduced overall survival. In conclusion, anticytokeratin mAbs are reliable probes for the immunocytochemical detection of single pancreatic cancer cells disseminated to bone marrow. Thus the described technique may help identify patients with pancreatic cancer and at potentially high risk of early metastatic relapse. The results promise to be of important assistance for determining prognosis and the consequences in therapy of early stage pancreatic cancer.

A randomized, double-blind multicenter trial was performed to compare the safety and efficacy of a new low-molecular-weight heparin (LMWH) (LU 47311, Clivarine) and standard unfractionated heparin for the prophylaxis of postoperative venous thromboembolism. Altogether 1351 patients scheduled to undergo abdominal surgery were included. Main outcome measures included the incidence of thromboembolic events (deep vein thrombosis, pulmonary embolism, or both) and bleeding complications, including wound hematoma. A total of 655 patients received 1750 anti-Xa IU of LMWH plus a placebo injection daily; 677 patients received 5000 IU of unfractionated heparin (UFH) twice a day. Both drugs were found to be equally effective, as 4.7% of patients in the LMWH group and 4.3% in the UFH group developed postoperative thromboembolic complications. However, the incidence of bleeding complications was significantly reduced in the LMWH group: 55 (8.3%) patients in the LMWH group and 80 (11.8%) in the UFH group developed bleeding complications, a relative risk (RR) of 0.70 (95% CI 0.51-0.97;p = 0.03); wound hematoma occurred in 29 (4.4%) of the LMWH group compared with 55 (7.7%) in those in the UFH group for an RR of 0.57 (95% CI 0.37-0.88;p = 0.01). This study confirmed that a very low dose of 1750 anti-Xa IU daily of this new LMWH is as effective as 10,000 IU of UFH for preventing postoperative deep vein thrombosis. At this dose its administration is associated with a significant reduction in the risk of bleeding including wound hematoma.

Minimal residual disease in patients with operable esophageal cancer is frequently missed by current noninvasive tumor staging. Here we applied an immunocytochemical cytokeratin assay that allows identification of individual esophageal carcinoma cells disseminated to bone marrow. Prior to therapy, bone marrow was aspirated from the upper iliac crest of 71 patients with esophageal cancer at various disease stages as well as an age-matched control group of 20 noncarcinoma patients. Tumor cells in cytologic bone marrow preparations were detected with monoclonal antibodies (mAbs) CK2, KL1, and A45-B/B3 to epithelial cytokeratins (CKs) using the alkaline phosphatase antialkaline phosphatase method. CK-positive cells were found in 14 (36.8%) of 38 cancer patients treated with curative intent and 16 (48.5%) of 33 patients with extended disease. The overall frequency of these cells was 1 per 4 x 10(5) to 82 per 4 x 10(5) mononuclear cells with no significant differences between patients at different tumor stages. After a short median follow-up of 9.5 months (3-24 months), 7 of 11 patients who underwent complete surgical resection but had tumor cells in bone marrow presented with tumor relapse compared to 2 of 19 corresponding patients without such cells (p < 0.01). It was concluded that although bone marrow is not a preferential site of overt metastasis of esophageal cancer, the frequent occurrence of isolated tumor cells at this distant site indicates that hematogenous dissemination of viable malignant cells occurs early in tumor progression.