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Biomedical subjects

D L Morton

Publications and source records attributed to D L Morton.

At least 289 records · Page 16Linked to original sources
PubMed1982

Clinical radiofrequency hyperthermia: a review.

Localized radiofrequency (RF) hyperthermia is being investigated for potential use in cancer therapy, both as a single agent and in combination with radiation therapy and chemotherapy. Standard capacitive and inductive heating techniques and new technology, including magnetrode magnetic-loop induction, are being compared for safety and efficacy. Clinical trials suggest that effective localized RF hyperthermia may be administered safely to both superficial and deep visceral tumors with proper equipment. Temperatures of 42 degrees C or greater appear to be tumoricidal, though higher temperatures and longer and multiple treatments seem most beneficial. Effective heating of tumors has been independent of histology but could be related to size and blood flow. Combined with radiation therapy and chemotherapy, hyperthermia appears to have a synergistic or additive effect. These trials indicate that localized RF hyperthermia may soon provide a significant contribution to our armamentarium against cancer.

Adenocarcinoma↗
PubMed1981

Development of an enzyme immunoassay to detect and quantitate tumor-associated antigens in the urine of sarcoma patients.

This study describes the development of an enzyme immunoassay (EIA) to quantitate antigen in the urine of sarcoma patients and compares its results with those of the authors' previously reported complement fixation assay. Three populations were studied for the presence of urinary antigen by EIA: (1) sarcoma patients who developed metastatic disease after resection of their primary tumor; (2) sarcoma patients who remain clinically disease-free two years after resection of their primary tumor; and (3) normal volunteers with no history of malignant disease. EAch group consisted of nine individuals. None of the urines from normal volunteers and none from sarcoma patients who remained free of disease for two years had elevated antigen titers detectable by EIA. However, all nine patients who developed pulmonary metastatic disease ahd significantly elevated levels of antigen in their urine prior to clinical evidence of disease recurrence. The day-to-day fluctuations in antigen titer detectable by EIA tended to parallel the levels detected by the complement fixation assay. However, EIA detected a significant elevation in antigen titer one to four months earlier than the complement fixation assay in four of the patients in whom disease recurred.

Antigens, Neoplasm↗
PubMed1981

Retroperitoneal sarcomas: a reappraisal of treatment.

Retroperitoneal sarcoma, regardless of the histopathologic grade of malignancy, has a high incidence of local recurrence that is usually fatal. Surgical resection is mandatory and resectability may be improved by a midline transabdominal approach. However, even with total tumor excision, recurrence is high. A preliminary study, combining resection and preoperative adriamycin, found to be effective for established disease, suggests potentially improved prognosis. Further clinical trials employing combined with adjuvant chemotherapy are warranted.

Adolescent↗
PubMed1981

Radio frequency hyperthermia of advanced human sarcomas.

Hyperthermia greater than or equal to 42 degrees C is tumoricidal in vitro and in many animal models, although such temperatures have only recently been achieved experimentally in some human cancers. A recently developed radio frequency device that provides safe hyperthermia to any depth without surface tissue injury now permits evaluation of the effects of hyperthermia on advanced human sarcomas. Twelve patients with large sarcomas located intraabdominally [7], in the chest wall [2], proximal extremity [2], and the neck [1], were evaluated in this study. Tumor types include liposarcoma [3], rhabdomyosarcoma [2], leiomyosarcoma [2], neurofibrosarcoma [2], and one each malignant mesothelioma, undifferentiated sarcoma, and osteosarcoma. Intratumor temperatures greater than or equal to 42 degrees C were observed in all tumors, with virtually no normal tissue injury. Selective tumor heating greater than or equal to 45 degrees C occurred in 9/12 (75%) and greater than or equal to 50 degrees C in 6/12 (50%). One to five weekly treatments greater than or equal to 50 degrees C and ten daily treatments greater than or equal to 45 degrees C resulted in significant tumor necrosis and pain relief in some patients. Hyperthermia of advanced sarcomas is possible with little host toxicity and may be of potential therapeutic benefit.

Adult↗
PubMed1981

Cell-mediated immunity is depressed following cardiopulmonary bypass.

Sequential in vitro lymphocyte function tests in 13 patients undergoing cardiac operation were performed to determine factors that contribute to depressed cell-mediated immunity following operation. Lymphocytes were stimulated with phytohemagglutinin (PHA), pokeweed mitogen, concanavalin A (Con A), and mitomycin-treated, pooled, allogeneic lymphocytes (MLC). Mitogen responses were measured by 3H-labeled thymidine incorporation. Circulating levels of T, B, and Fc-receptor lymphocytes were determined by counting E, EAC, and EA rosettes. Serum cortisol was measured by radioimmunoassay. The T-cell-dependent lymphocyte responses (PHA, Con A, and MLC) were significantly decreased 24 hours after operation, and this was accompanied by a 60% decrease in circulating T-cell levels. The PHA, Con A, and MLC responses, and circulating T-cell levels returned to preoperative values one week following operation. Lymphocyte responses to mitogens remained significantly decreased when the number of T cells in the postoperative cultures were adjusted to preoperative levels. This indicates that the T cells remaining after operation were functionally impaired. We conclude that lymphocyte proliferative responses and antigen recognition are significantly depressed following cardiac operation, and that these responses are related to decreased numbers of circulating T lymphocytes and depressed function of the remaining T lymphocytes.

Cardiopulmonary Bypass↗
PubMed1981

Melanoma. Associated antigens in benign melanocytic disorders.

Three instances of depigmentation occurring in children with congenital large nevocytic nevi are reported. Serologic studies for tumour-associated antigens to melanoma were performed by indirect immunofluorescence and complement fixation on these patients and others with benign melanocytic disorders. Positive reactivity in several children was observed. The small numbers studied and lack of uniformity of other testing methods leave open the question of relevance of such reactivity to malignant conversion or protection in congenital nevi.

Adolescent↗
PubMed1981

Oncofetal antigen-I: distribution in human tumors.

Oncofetal antigen-I (OFA-I) is a human tumor-associated fetal antigen that cross-reacts with fetal brain. The biological distribution of this antigen was studied in a variety of histologic types of human tumors and normal tissues. A total of 170 human tumors and 89 normal tissues obtained from biopsied and autopsied specimens were tested by immune adherence absorption assay. The antigen was most prevalent in malignant melanomas (82%); next in order of incidence were lung carcinomas (71%), sarcomas (61%), brain tumors (58%), and breast carcinomas (53%). However, OFA-I was found in only 15% of gastrointestinal tumors. The four hepatoma specimens tested were negative for OFA-I. OFA-I was also present in metastases and normal-appearing tissues of patients with OFA-I positive tumors but was not found in normal tissues from noncancer patients. These studies demonstrated that OFA-1 is widely distributed among human tumors. It appears to be more prevalent in tumors of ectodermal and mesodermal origin.

Antigens, Neoplasm↗
PubMed1981

Prolonged survival for melanoma patients with elevated IgM antibody to oncofetal antigen.

Antibody directed against a cultured melanoma cell line known to express an oncofetal antigen was measured in sera obtained from patients with stage II melanomas. This study was undertaken to determine if an inhibiting or enhancing effect on tumor growth would be suggested by a positive or negative correlation of antibody levels with tumor recurrence or patient survival. A positive correlation with disease-free interval and survival was detected among patients who had high levels of the IgM class of antibody before and shortly after surgery for state II disease. The IgG class of antibody over the period measured did not correlate consistently with tumor recurrence. Absorption of the IgM antibody with fetal brain confirmed that the dominant detectable reactivity was directed to the oncofetal antigen. The relevance of these findings is related to that of other evidence indicating that immunity to fetal antigens expressed on tumor cells is a participant in host-tumor interaction.

Antibodies, Neoplasm↗