Histological Grading Criteria Research Articles

Clinical points in diagnosis and treatment of mucoepidermoid tumor of the parotid gland ; Review of our cases

Two hundred and sixty-eight patients with parotid tumor were treated in our department from 1985-1994. Eight patientd (3 %) were with mucoepidermoid tumor. In all 8 cases, tumors were partially fixed to surrounding tissues. However, facial paralysis and pain were noted in one patient respectively. Seven patients were examined ultrasonographically. Malignant pattern was found in 6 cases and intermediate pattern in one, and boundary echo was unclear in all cases. Aspiration biopsy was performed in 6 cases ; malignancy was suggested in 5 cases, and 2 were diagnosed as mucoepidermoid tumor. Total parotidectomy with removal of involved surrounging tissue was done in all 8 patients. A regional lymph node dissection was done in 5 cases, and 2 had lymph node metastasis. Postorative radiotheraphy was done in 4 cases. Generally, a progonsis of mucoepidermoid tumors is good except for high grade malignant tumor, which have predominent epidermoid cells. In our cases, one have died of disease, and 7 patients are alive with no evidence of tumors. We propose a new histological grading criteria for mucoepidermoid tumors. Recommendations for treatment should be based no a histological grading of the tumor.

Detection of the growth fraction in colorectal tumours by a monoclonal antibody against DNA polymerase α

The cell kinetics of 54 colorectal tumours were examined by immunohistochemical methods, using the monoclonal antibody DNA polymerase alpha which reacts with an antigen found only in proliferating cells. The rate of DNA polymerase alpha positive cells in colorectal cancer was 44.8%, a figure that was significantly higher than the 21.9% found in colorectal adenomas. The rate of DNA polymerase alpha positive cells tended to rise as the degree of differentiation decreased according to the standard histological grading criteria for colorectal cancer. Positive cells were detected in much greater numbers in tumours with liver metastasis (55.4%) than in those without metastasis (41.7%). The rate of DNA polymerase alpha positive cells for aneuploid lesions was higher than that for lesions with a diploid pattern. The determination of growth fractions with a monoclonal antibody (DNA polymerase alpha) may be a biological marker of great prognostic significance.

The effect of histocompatibility matching on canine frozen bone allografts.

The value of histocompatibility matching in frozen bone allografts was studied in a canine cancellous ulnar segmental-replacement model. Frozen bone that was exchanged across strong and weak transplantation barriers was evaluated histologically and radiographically at thirteen and twenty-six weeks after grafting. Histological grading criteria quantified the type of union at each end of the graft and the degree of remodeling of the marrow, spongiosa, and compacta. Radiographic grading criteria included the presence of union at each end of the graft and the degree of remodeling of the graft segment. In vitro studies for serum antibody and cell-mediated immunity were carried out by isotopic cytotoxicity methods at seven intervals during the twenty-six-week study period. Histologically, the strong-barrier allografts had fewer osseous unions and less reorganization of spongiosa and marrow when compared with autograft controls at both thirteen and twenty-six weeks. Radiographically, the strong-barrier allografts at thirteen weeks had fewer unions and marked resorption of grafts material when compared with autograft controls. There were no differences between weak transplantation-barrier grafts and control autografts radiographically or histologically at thirteen and twenty-six weeks after grafting. Frozen bone allografts did not elicit detectable serum antibody or lymphocytes that were cytotoxic for donor cells.