Biomedical subjects
H Leber
Publications and source records attributed to H Leber.
[Cellular immunity during and after high-dose methotrexate therapy in patients with osteosarcoma (author's transl)].
Nine patients with osteogenic sarcoma and one patient with epitheloid sarcoma of bone undergoing treatment with high-dose methotrexate (MTX) therapy were studied immunologically. The following peripheral blood lymphocyte parameters were evaluated: 1-8 days after the intravenous infusion of 7.5 g MTX followed by leucovorin rescue: absolute count/mm3, the stimulatory response to the mitogens, phythemagglutinin (PHA) and pokeweed (PW) and the reactivity in the mixed lymphocyte culture (MLC). The response to PHA remained unaffected during the observation period, whereas the response to PW decreased on the 2nd and 4th day after treatment. The MLC response was inhibited between the 1st and the 4th day. The inhibition manifested itself first in the patients plasma and was demonstrable 48 hours later in the lymphocyte itself. The responsiveness regained normal or even reacted supranormal values about 7 days after treatment. Lymphocyte function remained essentially unaltered after several cycles of treatment. Absolute lymphocyte counts, however, tended to decrease. The MTX sensitive period in vitro lasts from the 2nd to the 6th day of the MLC, which is the period of intense RNA and DNA synthesis. We conclude that high-dose MTX therapy for osteogenic sarcoma leaves the patient without major permanent damage to cellular immune function.
[Clinical observations on the use of high-dose methotrexate treatment in osteogenic sarcoma (author's transl)].
Since January 1976 high-dose methotrexate (HDMTX) therapy has been used in the management of patients with osteogenic sarcoma at the Orthopaedic Department, University of Vienna. 7500 mg MTX/sqm body surface is administrated in a four-hour infusion with citrovorum factor rescue. This therapy is combined with dactinomycin, adriamycin, bleomycin, cyclophosphamide and vincristine in a multi-drug chemotherapeutic program as a prophylactic regimen after surgical treatment of the primary tumour, as well as in the management of metastases. So far, 12 patients have received a total of 46 infusions with HDMTX at montly intervals (6 patients already had widespread metastases). The use of several precautions such as adequate hydration 3 l/sqm body surface fluid), systematic alkalinization of the urine and regular control of the serum MTX level renders HDMTX therapy less hazardous. Five out of the 46 infusions were followed by mild toxic reactions consisting of mouth ulceration, fever and/or bone marrow depression. One out of the 6 patients with metastases and 5 out of the 6 patients receiving HDMTX as a prophylactic measure are without evidence of disease at present. In view of the short observation period, this report is limited to clinical observations only.
Tumor-specific immunity in sarcoma patients.
Stimulatory responses of 40 patients with bone [33] and soft tissue [7] sarcomas to autologous tumor cells were correlated with clinical data and prognosis. Although conclusive judgments for individual patients cannot be made, some genral features emerge: patients with stimulation indices greater than 1.5 have a 50 percent relapse-free interval after surgery of 22 months, patients with indices, below 1.5 have a 50 percent relapse-free interval of 5 months. 7 out of 10 responder patients are tumor-free 1 year after surgery as compared to 5 out of 19 (26 percent of non-responder pateints (p less than 0.05). Removal of the tumor is followed by an increase in the stimulatory response and by the dissappearance of blocking serum factors in patients with favourable prognosis. Responses return to baseline levels in tumor free patients 9-12 months after surgery. The results suggest that tumor-associated immune responses play a role in the development of human sarcomas. In addition, 47 lymphocyte samples of 25 patients were tested for stimulation by autologous tumor cells and for cell-mediated cytotoxicity against allogeneic sarcoma cell lines. Similar results were obtained in both test systems when pre-therapy lymphocytes were used. Discordant results were frequently seen at times after surgery. Both test systems may complement each other and may help clarify the tumor-specificity of certain lymphocytotoxic activities.
[The lateral profile of the lumbar vertebrae following lumbosacral spondylodesis--comparison between Harrington rods and a transpedicular fixation system (Zielke's USIS method)].
We compared the lateral profile of the lumbar spine after lumbosacral dorsal fusion in two groups of each 32 patients with comparable age, sex distribution and indication; one group had been fused with the use of two short Harrington rods, the other with the Universal Spinal Instrumentation System (USIS) according to Zielke/Harms. The sparing of motion segments using a transpedicular system is demonstrated by the average number of 1.7 fused motion segments compared to 2.2 with the Harrington rods. The average increase of cyphosis of the fused area could be reduced with USIS from 7.3 to 3.0 degrees in spite distraction. The greatest difference could be seen in cases of spondylolisthesis (2.0 degrees compared to 8.2) and in fusions including three segments (2.0 versus 7.0). No significant difference in total lordosis of the lumbar spine could be evaluated and there was no influence of preoperative mobility on the grade of postoperative cyphosis. The early results of lumbar fusion using USIS are clinically satisfying in spite of a relative high rate of rod fracture. measures to achieve a higher stability and diminish the rate of implant failure are discussed.