Stephen H. Bennett

Bio: Stephen H. Bennett is an academic researcher from National Institutes of Health. The author has contributed to research in topics: Autotransfusion & Perfusion. The author has an hindex of 8, co-authored 10 publications receiving 384 citations. Previous affiliations of Stephen H. Bennett include Walter Reed Army Medical Center.

Prognostic significance of histologic host response in cancer of the larynx or hypopharynx.

Abstract: A series of 84 patients with carcinoma of the larynx or hypopharynx was studied with regard to tumor host interaction. Prognostic evaluation of the “tumor” aspects of this interaction included preoperative staging (TNM), histologic grading of the primary tumor, and histologic examination for the presence of metastases confined to regional lymph nodes or extranodal spread. Morphological evidence of host resistance was judged by the presence and degree of lymphoid inflammatory infiltration around the primary tumor and factors suggestive of enhanced immune reactivity in lymph nodes, i.e., sinus histiocytosis, germinal center hyperplasia, plasmacytosis, and the presence of pyroninophilic blast cells. Of the factors evaluated, those which appeared to correlate best with 5-year survival were stage of disease, presence or absence of positive regional nodes, histologic grade of the primary tumor, lymphoid infiltration in the primary tumor, and extensive germinal center hyperpiasia in the regional nodes. The favorable prognosis attached to the presence of lymphoid infiltration or germinal center hyperpiasia, however, was not uniform for all patients. The presence of lymphoid infiltration was a favorable sign only in the group of patients with positive nodes or in those patients with well-differentiated (Grade I, II) tumors. The presence of extensive germinal center hyperpiasia was a favorable prognostic sign only in those patients with positive nodes or in those patients who had a poorly differentiated (Grade III, IV) tumor. None of the other morphological structures related to lymph node reactivity showed favorable prognostic significance. The relationship of morphology to host immune mechanisms was discussed.

Fluid volume and albumin kinetics occurring with major surgery.

Abstract: Studies investigating fluid volume dynamics and albumin kinetics in patients undergoing major abdominal surgery indicate that during the operation, marked deficits develop in the total red blood cell volume, plasma volume, extracellular fluid volume, and the total exchangeable albumin pool. A disproportionate deficit in the plasma volume occurring in the course of the operation is believed to be secondary to a functional extracellular fluid volume deficit and abnormal losses of albumin from the intravascular compartment. Deficits in these compartments occurred during the operation in every patient studied. In some patients the plasma volume deficit immediately postoperatively amounted to close to 50% of the volume present when the patient went into the operating room. In the course of a regional node dissection in nine patients studied, a 29% deficit developed in the total body albumin pool.

Effects of autotransfusion on blood elements

Abstract: The effects of autotransfusion on cellular and other components of autologous blood were studied in forty adult dogs. An increase in free plasma hemoglobin and a decrease in hematocrit, red blood cells, and white blood cells were seen immediately after autotransfusion with canine blood exposed to the peritoneal cavity (group II) and blood collected in a siliconized beaker (group I). After autotransfusion, a significant decrease in platelets and a significantly higher free plasma hemoglobin level were noted in dogs in group II. In the five day period after autotransfusion the white blood cell and fibrinogen levels remained elevated whereas free plasma hemoglobin, hematocrit, red blood cell, and platelet levels returned to near normal. Prothrombin time, thrombin time, and partial thromboplastin time were within normal limits throughout the experimental period. Red blood cell survival after autotransfusion was found to be normal relative to controls. Screen filtration pressure was markedly elevated in blood suctioned from the abdominal cavity. Filtration with the autotransfusion reservoir filter resulted in a decrease in screen filtration pressure to a measurable but elevated level whereas screen filtration pressure returned to normal after Dacron wool filtration. No alteration in lipoproteins or elevation of plasma lipids was found with prolonged autotransfusion and no fat emboli were observed histologically. All dogs survived and showed no evidence of bleeding, thrombosis, or insult to pulmonary or other organ system function.

Pulmonary effects of autotransfused blood: A comparison of fresh autologous and stored blood with blood retrieved from the pleural cavity in an in situ lung perfusion model

Abstract: An in situ pulmonary lobe perfusion model in dogs was used to examine the pulmonary effects of autotransfused blood as compared with fresh and stored blood. Fresh arterial blood was collected in heparin solution from ten dogs and was drained into and collected from the pleural cavity using a commercially available autotransfusion device for continuous filtration. Results of perfusion with autotransfused blood were compared with results of perfusion of blood stored at 4 °C in ACD solution for twenty-four hours in seven dogs and those of perfusion of blood stored for twenty-one days at 4 °C in ACD solution in seven dogs. The fresh and stored blood samples were passed through a standard recipient set filter prior to perfusion. Perfusion with autotransfused blood resulted in a decreased arteriovenous pO 2 gradient as compared with results in control blood, but there was no concomitant elevation in pulmonary vascular resistance (PVR) or endobronchial pressure (P b ) for the autotransfused blood. Stored blood by comparison showed significantly increased PVR and P b but a progressive decline in A-VpO 2 which was in excess of the level reached by perfusion of autotransfused blood. Fresh blood showed essentially no change in pulmonary functional parameters during perfusion. The great majority of animals whose lungs were perfused with stored blood had microscopic evidence of interstitial pulmonary edema, perivascular hemorrhage, intra-alveolar fluid, and alveolar congestion. Significantly fewer animals showed these changes when lungs were perfused with autotransfused or fresh blood. Wet-dry weight ratios of lung tissue after perfusion indicated significantly higher uptake of water by the lung perfused with stored blood than by those perfused with autotransfused or fresh blood.

The biology of cancer invasion and metastasis.

Abstract: Publisher Summary This chapter summarizes the findings and hypotheses of cancer metastasis and elucidates the complex mechanisms involved in the pathogenesis of metastasis. The development of a metastasis is dependent on the interplay of host and tumor cell properties. The process is complex, highly selective, and represents the end stage of several destructive events from which few tumor cells survive. Malignant neoplasms may consist of a variety of subpopulations of cells with differing capabilities for invasion and metastasis. Only a few tumor cells within a primary neoplasm may actually invade blood vessels, and of those, even fewer survive in the circulation. The unique characteristics of tumor cells, including modifications in cell surface properties, adhesive capacities, cell motility, and enzyme secretion, are of paramount importance in determining the eventual outcome of the metastasis. Such acquired properties of malignant cells allow for interaction with host tissues and cells, which leads to tumor cell survival and growth. Three mechanisms are invoked to explain tumor cell invasion—(1) the rapid multiplication of malignant cells leading to growth and infiltration by mechanical pressure, (2) the destruction of host tissue by the products of the tumor cell, and (3) the lack of tumor cell adhesiveness accompanied by an increase in the cell motility.

Transfusion-related acute lung injury : Definition and review

Abstract: Background:Transfusion-related acute lung injury (TRALI) is now the leading cause of transfusion-associated mortality, even though it is probably still underdiagnosed and underreported.National Heart, Lung, and Blood Institute Action:The National Heart, Lung, and Blood Institute convened a working g

The Extracapsular Spread of Tumors in Cervical Node Metastasis

Abstract: • Extracapsular spread (ECS) of lymph node metastases is believed to be an indicator of poor prognosis. In general, it has been thought that ECS was limited to large "fixed" nodes. To test the validity of the assumption that nodes less than 3 cm in diameter do not have ECS, the specimens from 177 radical neck dissections were reviewed retrospectively with regard to ECS. Sixty-five percent of the nodes that were 2.9 cm or less in diameter were found to demonstrate ECS. We found no substantial difference in the number of patients who had no histologic disease in their necks when compared with a second group of patients who had metastasis confined to the lymph node. The patients whose lesions had ECS had statistically significantly reduced numbers of survivors. Other factors, eg, tumor differentiation and the number of malignant nodes, had no prognostic importance. The impact of ECS on staging, the reporting of retrospective reviews, and therapy are discussed. ( Arch Otolaryngol 1981;107:725-729)

Gastric carcinoma with lymphoid stroma. Its morphologic characteristics and prognostic correlations

Abstract: A type of gastric carcinoma was specified under the designation carcinoma with lymphoid stroma. Grossly, this carcinoma was characterized by clear circumscription, usually with a central ulceration. A histologic feature distinguishing this carcinoma was the presence of a nondesmoplastic stroma infiltrated uniformly with an abundance of lymphocytes and plasma cells throughout the entire area of the tumor. Sparse population of less pleomorphic cancer cell nests of thin trabecular, microalveolar, or primitive tubular pattern widely separated by the intervening stroma was another feature peculiar to this tumor. Carcinoma of this type was found in 4% of a total of 1041 cases of gastric carcinoma removed surgically. A high survival rate was noted among the patients undergoing surgery for this carcinoma. A proposal was made on the separate classification of this tumor from common gastric carcinomas.