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Biomedical subjects

Z Fuks

Publications and source records attributed to Z Fuks.

At least 163 records · Page 9Linked to original sources
PubMed1989

Brachytherapy as part of the definitive management of squamous cancer of the base of tongue.

Between 1981 and 1986, 17 patients were treated at the Department of Radiation Oncology at the Memorial Sloan-Kettering Cancer Center with squamous cancer of the base of the tongue whose definitive treatment included brachytherapy. The patient sample consisted of 14 men and 3 women with age range of 35 to 71 years (median = 58). There were four patients with T1 lesions, six with T2, six with T3, and one with T4. In general, treatment consisted of 5000-5400 cGy with external beam radiation and 2000-3000 cGy boost to the base of tongue via an Ir-192 implant using afterloading catheters. Necks were managed with elective radiation alone in the N0 group (n = 5) or with radiation plus neck dissection in the N+ group (n = 12). Five patients who would have required laryngectomy had they undergone primary surgery received neoadjuvant chemotherapy followed by external beam and implant as part of a larynx preservation study that was being done at our institution (4-T3, 1-T2). The range of follow-up is 8 to 59 months, with median follow-up of 24 months. No patients have been lost to follow-up. Crude local control by T-Stage are as follows: T1-4/4, T2-5/6, T3-5/6, T4-1/1. Actuarial local control at 24 months is 87%. There have been no neck failures. There have been five patients who had soft tissue ulceration (STU) and one patient who had osteoradionecrosis (ORN). All soft tissue ulceration patients have been successfully managed conservatively. The patient with osteoradionecrosis is currently being managed. In 4 of these 6 cases, the implant was the initial therapeutic intervention and the entire tumor bed was implanted. On the other hand, when external beam was the initial treatment, the boost was administered to the smaller volume of residual disease. Overall, 4 of 7 patients who had implant first developed either soft tissue ulceration or osteoradionecrosis, as opposed to 2 of 10 patients who had implant after external beam and/or chemotherapy. The numbers are too small to be statistically significant, but our current policy is to perform brachytherapy after the external beam. In addition, all those with either soft tissue ulceration or osteoradionecrosis were implanted with a non-looping technique. Overall, 6 of 12 patients treated with a non-looping technique developed an injury, whereas none of the five treated with a looping technique has developed one.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1989

Perturbation of endothelial functions by ionizing irradiation: effects on prostaglandins, chemoattractants and mitogens.

Numerous studies have shown that early radiation injury is characterized by vascular damage and that the initial site of damage appears to be the EC lining of the vessel wall. Chronic irreversible tissue reactions to radiation include thrombotic occlusion of capillaries, enhanced atherosclerosis in larger vessels, inflammatory changes, and late tissue fibrosis. These processes may be mediated by endothelial products released as a result of cellular injury. Using EC cultures, we show that ionizing irradiation affects one of the major vascular defense mechanisms against platelet activation, thrombosis, and atherosclerosis--the capacity to produce PGI2. Dose- and time-related damage to enzymes of the arachidonic acid cascade were demonstrated. Radiation damage is associated with oxidant stress and production of free radicals. The oxygen radical scavenger, vitamin C, was found to protect the capacity of irradiated ECs to produce PGI2. Radiation injury often induces an acute inflammatory response. We found that irradiated ECs release a chemotactic factor for neutrophils, which is a lipid product of the lipoxygenase pathway. Late radiation-induced tissue fibrosis and the capacity of radiation to enhance arteriosclerosis may involve participation of mitogens released from perturbed and damaged ECs. We show that conditioned medium of irradiated ECs contain larger amounts of newly synthesized mitogens capable of stimulating the proliferation of fibroblasts, SMCs, and ECs. Hence, it may be assumed that the mitogenic activity released by irradiated ECs includes both PDGF and FGF-like mitogens.

Animals↗
PubMed1989

Basic fibroblast growth factor is an extracellular matrix component required for supporting the proliferation of vascular endothelial cells and the differentiation of PC12 cells.

Vascular endothelial cells (ECs) seeded sparsely on extracellular matrix (ECM) will proliferate in the absence of exogenous basic fibroblast growth factor (bFGF). This ECM will also stimulate neurite outgrowth in PC12 cells in the absence of exogenous growth factors. We have previously shown that bFGF is found in subendothelial ECM (Vlodavsky, I., J. Folkman, R. Sullivan, R. Fridman, R. Ishai-Michaeli, J. Sasse, and M. Klagsburn. 1987. Proc. Natl. Acad. Sci. USA. 84:2292-2296) and in basement membranes (Folkman, J., M. Klagsburn, J. Sasse, M. Wadzinski, D. Ingber, and I. Vlodavsky. 1988. Am. J. Pathol. 130:393-400). The actual requirement of ECM-associated bFGF for the growth of ECs and differentiation of PC12 cells was shown in two ways. First, polyclonal anti-bFGF antibodies added to subendothelial ECM inhibited both EC proliferation and PC12 neurite outgrowth. Secondly, PF-HR-9 cells, which do not synthesize bFGF and which produce an ECM not permissive for EC proliferation and PC12 neurite outgrowth, were transfected with bFGF cDNA. PF-HR-9 cells transfected with bFGF, but not with the dominant selectable marker SV2-neomycin, were found to express bFGF and to produce an ECM which did support both EC proliferation and PC12 differentiation. The ECM-mediated stimulatory effects were inhibited by anti-bFGF antibodies but not by anti-nerve growth factor antibodies or nonimmune rabbit IgG. These results indicate that bFGF associated with ECM is a required ECM component for ECM-mediated cell proliferation and differentiation.

Adrenal Gland Neoplasms↗
PubMed1989

The role of postoperative radiotherapy after resection of single brain metastases.

To assess the value of whole brain radiotherapy (WBRT) after complete resection of a single brain metastasis we reviewed the records of 98 patients who had elective craniotomy between 1978 and 1985. Seventy-nine patients received postoperative WBRT (Group A) and 19 patients no radiotherapy (RT) (Group B). Neurological relapse was designated as local (i.e., at the site of the original metastasis) or distant (i.e., elsewhere in the brain). Postoperative WBRT significantly prolonged the time to any neurological relapse (P = 0.034) with a 1-year recurrence rate of 22% in Group A and 46% in Group B patients; however, it did not specifically control either local or distant cerebral recurrence. Recurrence of metastatic brain disease was not affected by location of the original lesion; however, meningeal relapse occurred in 38% of cerebellar lesions, but only in 4.7% of supratentorial metastases (P = 0.003). The total radiation dose or fractionation scheme of RT did not affect survival nor time to neurological relapse. The median survival was 20.6 and 14.4 months for Groups A and B, respectively (not statistically different). Forty-eight percent of Group A and 47% of Group B patients survived for 1 year or longer; however, 11% of patients who had received RT and survived 1 year developed severe radiation-induced dementia. All patients with radiation-related cerebral damage received hypo-fractionated RT with high daily fractions as commonly designed for rapid palliation of macroscopic brain metastases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Generation of lipid neutrophil chemoattractant by irradiated bovine aortic endothelial cells.

Radiation injury to blood vessels is associated with an acute inflammatory process. We investigated the capacity of cultured bovine aortic endothelial cells (BAEC) to produce chemotactic factors after radiation injury. BAEC in serum-free media were irradiated with a cobalt-60 Gammacell 220 and the cell supernatants were assayed for chemotactic activity for human neutrophils in a Boyden chamber. There was a rapid release of chemotactic activity into the BAEC supernatants which was dependent both on the dose of radiation (5 to 40 Gy) and the time between irradiation and sample collection. In contrast, isolation of BAEC lysates by freeze-thawing was not associated with the presence of similar chemotactic activity. The chemotactic activity released from the irradiated BAEC was not destroyed by boiling nor by treatment with trypsin. The release of the chemotactic activity was, however, inhibited by the addition of a lipoxygenase inhibitor but not by the addition of a cyclooxygenase inhibitor before the irradiation. The chemotactic activity was recovered from the cell supernatants in the lipid phase after extraction with chloroform/methanol. Furthermore, the chloroform/methanol extracts co-eluted with authentic leukotriene B4 when the BAEC were prelabeled with [14C] arachidonic acid. However, we were unable to detect endogenous leukotriene B4 with RIA. Instead, the only detectable endogenous lipid present in the supernatants was 13-hydroxyoctadecadienoic acid which is derived from linoleic acid via the lipoxygenase pathway. 13-Hydroxyoctadecadienoic acid, however, had no chemotactic activity. These findings suggest that endothelial cells rapidly release a chemotactic agent after irradiation, the release of which is associated with a lipoxygenase pathway. The release of this chemotactic activity may account in part for the acute inflammatory response that is observed after ionizing irradiation.

Animals↗
PubMed1988

Cerebral necrosis following neutron radiation of an extracranial tumor.

Radiation necrosis of the brain is a rare complication of irradiation for extracranial tumors. We present a patient who emphasizes the potential hazard of neutron therapy, the sensitivity of magnetic resonance imaging (MRI) which may detect white matter changes prior to the development of clinical symptoms, the potential diagnostic value of 18F-fluorodeoxyglucose/positron emission tomography, and the importance of a combined surgical and medical approach for proper treatment.

Brain↗
PubMed1988

Differentiating human leukemia cells express heparanase that degrades heparan sulfate in subendothelial extracellular matrix.

Human promyelocytic (HL-60) and monoblast-like (U-937) leukemia cell lines were tested for expression of an endoglycosidase (heparanase) capable of degrading heparan sulfate (HS) side chains in the subendothelial extracellular matrix (ECM). Heparanase activity has been previously shown to be expressed by activated lymphocytes and macrophages and by highly metastatic tumor cells, in correlation with their ability to invade blood vessels and extracellular matrices. Incubation of HL-60 and U-937 cells with sulfate-labeled ECM in the presence of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) resulted in heparanase-mediated release of heparan sulfate degradation products. This degradation was inhibited by heparin, stimulated by plasminogen and not expressed by cells treated with retinoic acid or dimethylsulfoxide and undergoing neutrophilic differentiation. Heparanase activity was not detected in media conditioned by HL-60 and U-937 cells but was found in their cell lysates, regardless of whether or not the cells were exposed to TPA. These findings imply that TPA-induced differentiation of human myeloid leukemic cells to macrophage-like cells, but not to neutrophilic granulocytes, is associated with expression on the cell surface of a preformed heparanase activity. The enzyme may serve as a marker for human cell differentiation into macrophages, allowing the differentiating cells to traverse the vascular compartment and reach their target sites.

Cell Line↗
PubMed1988

Improved survival of poor prognosis diffuse histiocytic (large cell) lymphoma managed with sequential induction chemotherapy, "boost" radiation therapy, and autologous bone marrow transplantation.

From 1981 to 1985, 33 patients with the diagnosis of diffuse histiocytic (large cell) lymphoma (DHL) with a poor prognosis received induction multi-drug chemotherapy followed by autologous marrow cryopreservation. Thirty patients who had residual disease after chemotherapy were given "boost" irradiation to these sites, followed immediately by hyperfractionated total body irradiation, 1320 to 1375 cGy in 11 fractions over 4 days, then cyclophosphamide (60 mg/kg/d) for 2 days. All patients received an autologous bone marrow transplant (ABMT), with 15 patients receiving marrow purged with 4-hydroperoxycyclophosphamide. Patients were transplanted either as part of a planned induction-transplant approach (Group I), or as salvage after relapse on the same induction regimen (Group II), or other conventional chemotherapy regimens (Group III). In the entire group, 16 of 33 patients (48%) are alive free of lymphoma with a median follow-up of 32 months (11 to 53 mo). Actuarial (Kaplan-Meier) survival is 51% at 2 years and 46% at 3 years, with only 1 patient dying after 2 years out of 11 at risk. Eight patients (24%) succumbed to early treatment related complications. Nine patients (27%) died from relapse. Patients receiving ABMT as planned sequential therapy post-induction (Group I) did significantly better than patients given ABMT as salvage therapy after relapse on prior chemotherapy (Groups II and III) and better than the historical group of patients treated with chemotherapy alone. At 2 years, the survival in Group I is 79% versus 0% for Group II versus 48% for Group III. Historically, this group of high risk patients had a 2-year disease-free survival of 20% or less with chemotherapy alone.

Adolescent↗
PubMed1988

Preliminary results of alternating combination chemotherapy (CT) and hyperfractionated radiotherapy (HART) in advanced rhabdomyosarcoma (RMS).

In an attempt to reduce treatment (Rx) related acute toxicity and improve protocol compliance without compromising local control nor overall survival, a Phase II single arm pilot employing alternating intensive multiagent CT and radiotherapy (RT) in children with gross residual or metastatic RMS was begun at Memorial Sloan-Kettering Cancer Center (MSKCC) in 1984. Hyperfractionated radiotherapy (HART) was adopted to allow for timely delivery of both the RT and CT. From July, 1984 through July, 1986 12 patients (pts), aged 2 to 23 yr (median 10 yr) were enrolled on study. CT treatment was delivered over approximately 14 months and included 2 induction and 5 maintenance cycles. The induction CT consisted of two repetitive cycles of Vincristine, Dactinomycin, Cyclophosphamide, Adriamycin, Bleomycin, and Methotrexate; the maintenance CT included the same agents as reduced drug doses. The HART was delivered to the primary site during cycle I of induction at fractions of 150 cGy BID to a total dose of 5400 cGy in 2 courses of 3000 cGy and 2400 cGy, respectively. One hundred percent of patients completed the recommended dose of HART; 0% required unplanned interruptions of HART due to treatment toxicity. With a median follow-up (f/u) from diagnosis of surviving patients of 25 months (range 20-30), the local control rate is 83% (10/12 pts) and the overall survival, 58% (7/12 pts). The median time (MT) to any failure, local or metastatic, is 9 months (mo); and to death, 14 mo. Comparison of results with 12 historical controls with concomitant split-course standard fractionation RT (180-200 cGy/per fraction) and T6 CT during a MSKCC trial from 1975-1984, matched by site and stage of primary, revealed that 9 pts (75%) completed the recommended dose of RT, and 7 pts (58%) required interruptions of RT. With a median f/u of 78 mo (range 34-109), the local control rate was 75% (9/12 pts) and the overall survival, 42% (5/12 pts). The MT to any failure was 14 mo; and to death, 18 mo. These results indicate that the mode of alternating CT and HART (HART T6) as employed in this pilot study is well tolerated. It appears to offer a significant improvement in protocol compliance over previous protocols using concomitant CT and RT without any apparent compromise in local primary control or survival rates with a median f/u suggestive of adequate elapsed time for the appearance of most relapses and deaths in advanced RMS.

Adolescent↗
PubMed1988

A comprehensive three-dimensional radiation treatment planning system.

A comprehensive software system has been developed to allow 3-dimensional planning of radiation therapy treatments using the extensive anatomical information made available by imaging modalities such as CT and MR. Biological structures of interest and tumor volumes are defined by outlines drawn on a sequence of CT slices. Beam set-ups may then be determined in three dimensions by displaying the structure contours in a beam's eye view, or in two dimensions using a single CT cut. Each beam defined may be shaped by the specification of block aperture contours, and its intensity may be modified with the use of planar compensators. 3D dose calculation algorithms are discussed. To evaluate the calculation results, dose volume histograms are provided, as well as various types of displays in two and three dimensions, including dose on arbitrarily oriented planes, dose on the surface of anatomical objects, and isodose surfaces. Computer generated beam films are also available as an aid in patient set-up verification. These tools, and others, provide the basis for a comprehensive 3D system that can be used throughout the treatment planning process.

Humans↗
PubMed1988

Chemotherapeutic and surgical induction of pathological complete remission and whole abdominal irradiation for consolidation does not enhance the cure of stage III ovarian carcinoma.

Thirty-eight patients with stage III ovarian carcinoma were treated with a protocol consisting of an initial phase of induction of remission with cyclophosphamide, hexamethylmelamine, doxorubicin, and cisplatin (CHAD) combination chemotherapy and a second laparotomy for resection of residual tumors, followed by a consolidation phase with curative doses of whole abdominal radiation. Six patients (16%) had stage IIIA disease, ten (26%) IIIB, and 22 (58%) had stage IIIC disease. All patients received three to 14 courses of CHAD chemotherapy with a clinical response rate (complete [CR] and partial [PR]) of 91%. Thirty-three patients underwent the second operation. In 14 patients no residual tumor was found, and in another 11 residual tumors found were totally resected. Thus, 25 of 33 (76%) were classified as in pathological complete remission (PCR) after this operation. Whole abdominal irradiation was well tolerated, although 12 of 29 (42%) of the irradiated patients required more than a 2-week interruption of the treatment course because of leukopenia and/or thrombocytopenia. The actuarial 5-year survival and disease-free survival rates for the whole group were 27% and 17%, respectively, and for the 29 patients who received the complete sequence of the prescribed protocol treatments, 35% and 20%, respectively. A univariate analysis of clinical parameters showed that inherent biological features, such as histology and grade, were the most dominant factors affecting prognosis, and that neither the aggressive surgical approach employed, nor the high-dose whole abdominal irradiation, significantly affected the outcome. The long-term results suggest that although our combined modality protocol was well tolerated, it failed to enhance the cure of stage III ovarian carcinoma. The possible biological and therapeutic vectors affecting this outcome are discussed.

Abdomen↗
PubMed1987

Soluble antigen induces T lymphocytes to secrete an endoglycosidase that degrades the heparan sulfate moiety of subendothelial extracellular matrix.

The antigen-mediated induction of heparanase, an endoglycosidase capable of degrading heparan sulfate from the subendothelial extracellular matrix (ECM), was investigated in a rat T lymphocyte cell line reactive against the basic protein (BP) of myelin. We found that nonactivated T lymphocytes could be induced to express heparanase activity following exposure to soluble but not to ECM-bound BP. The induction of heparanase was immunologically specific and independent of the presence of syngeneic or allogeneic antigen presenting cells (APC). However, anti-IA antibodies inhibited heparanase expression. Soluble BP induced secretion of heparanase into the culture medium within minutes, despite inhibition of protein synthesis. Cell lysates of T lymphocytes contained heparanase activity. Thus, T lymphocytes secrete a preformed heparanase following exposure to specific antigen.

Animals↗
PubMed1987

Recovery of prostacyclin capacity of irradiated endothelial cells and the protective effect of vitamin C.

Ionizing irradiation has been reported to affect prostacyclin (PGI2) production by intact blood vessels and cultured endothelial cells (EC) due to damage of enzymes of the arachidonate cascade. In the present study, we investigated whether EC can recover from radiation injury and regain their capacity to produce PGI2. Bovine aortic EC were exposed to radiation doses of 3 and 6 Gy and their capacity to produce PGI2 in response to stimulation with arachidonic acid was tested, at various times after irradiation. The results of these experiments showed clearly that EC exposed to single or fractionated irradiation could recover their capacity to produce PGI2 depending on the radiation dose and the time period following radiation. Radiation damage is associated with oxidant stress and the production of free radicals. We therefore tested the ability of an oxygen radical scavenger, vitamin C, to protect the capacity of irradiated EC to produce PGI2. Pretreatment of EC with low concentrations of vitamin C inhibited the radiation induced release of PGI2 to the culture medium. Vitamin C also enhanced the capacity of irradiated EC to produce PGI2 following short stimulation with arachidonic acid. Treatment with this scavenger however, did not protect the cells against the cytopathic effects of radiation.

Animals↗
PubMed1987

Is cranial radiation necessary for CNS prophylaxis in pediatric NHL?

The records of 95 consecutive children less than or equal to 21 years of age with previously untreated diffuse histology NHL registered in our protocols from 1978 to 1983 were reviewed. Seventy-nine patients were considered eligible for analysis. The histologic subtypes represented included lymphoblastic (LB) 37%; histiocytic (DHL) 29%; undifferentiated (DU) 19%; poorly differentiated (DPDL) 9%; and unclassified (UNHL) 6%. Distribution of the patients according to stage showed Stage I, 0%; Stage II, 11%; Stage III, 53%; Stage IV, 36%. Four different Memorial Hospital protocols for systemic chemotherapy were used (LSA2L2 73%; L10 9%; L17 10%; L17M 8%); however, the IT (intrathecal) chemotherapy was uniform (Methotrexate: 6.0-6.25 mg/M2 per treatment course) and was included in the induction, consolidation, and maintenance phases of all treatment protocols. Cranial radiation was included in the induction, consolidation, and maintenance phases of all treatment protocols. Cranial radiation was not included in the CNS prophylaxis program. The overall median time of follow-up was 43 months. The overall CNS relapse rate was 6.3%, however, the incidence of CNS lymphoma presenting as the first isolated site of relapse in patients in otherwise complete remission (minimum follow-up of 19 months with 97% of patients off treatment) was only 1/58 (1.7%). Our data suggests that IT chemotherapy when given in combination with modern aggressive systemic combination chemotherapy, and without cranial radiation appears to be a highly effective modality for CNS prophylaxis regardless of stage, histology, or bone marrow or mediastinal involvement. Therefore, with the commonly used aggressive combination chemotherapy for the management of all stage diffuse pediatric NHL, and the known increased risk of leukoencephalopathy with combination of cranial radiation and intensive systemic and intrathecal chemotherapy, we believe that cranial radiation may not be indicated for CNS prophylaxis in pediatric NHL.

Adolescent↗
PubMed1987

Combined surgery and radiation in endometrial carcinoma: an analysis of prognostic factors.

From 1969 to 1979, 300 patients with the diagnosis of endometrial cancer operated elsewhere were referred for treatment to the Department of Radiation Oncology at Memorial Sloan-Kettering Cancer Center. All the patients were staged according to FIGO classification. One hundred and seventy-three patients were Stage IA, 105 patients were Stage IB, and 22 patients were Stage II. Within Stage IA, 141 patients had well differentiated tumor (G1), 20 had moderately well differentiated tumor (G2), and 12 patients had poorly differentiated (G3). One hundred and thirty-three patients had superficial myometrial invasion and 40 patients had deep myometrial invasion. Within Stage IB, 69 patients had G1 tumor, 23 had G2, and 13 had G3 tumors. Seventy-four patients in this group had superficial myometrial invasion and 31 patients had deep myometrial invasion. Two hundred and eighty-three patients had adenocarcinoma, 13 patients had adenoacanthoma, 4 patients had adenosquamous and other histological types. All of the patients received combined surgery (total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH/BSO) and radiation. The radiation treatments consisted of external pelvic radiation and intravaginal vault radiation. External pelvic radiation was delivered with a megavoltage apparatus for a total dose of 4,000 cGy in 4 weeks preoperatively (47 patients) or postoperatively (105 patients) in patients presenting with high grade (G2,G3), more than 1/3 myometrial invasion, Stage II and extrauterine extension of disease at surgery. All patients received in addition, postoperative intravaginal vault irradiation consisting of 2100 cGy in 3 fractions over 4 weeks with a high dose rate remote afterloading technique. The follow-up in these patients ranged from 5-14 years. Survival data was calculated according to Kaplan-Meier Method and Cox regression multivariate analysis to identify the prognostic factors. The 10-year survival rate in Stage IA was 91%; in Stage IB 75%; and in Stage II it was 71%. Eleven patients (4%) developed recurrent disease with either local and/or distant metastasis. Nine-percent of the patients developed mild to moderate complications which resolved with conservative treatment. Patients with gross extra-uterine pelvic extension of disease had a poor survival compared with those presenting with microscopic involvement (40% vs. 80% at 5-years). No statistically significant difference in survival was observed between patients who received either preoperative or postoperative external pelvic irradiation.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗