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The ultrasonographic appearance of a diffusely infiltrating gastric lymphosarcoma is presented. The stomach appeared as a large mass with sonolucent periphery and central sonodensity. This appearance should suggest a lesion arising from the gastrointestinal tract.
Mucopolysaccharide was prepared from media in which the Gardner's lymphosarcoma cells were cultured. Multiple intraperitoneal injections of the preparation into syngeneic mice resulted in enhancement of the tumors which were inoculated prior to the injections. Sera of these hosts contained antibodies reacting with antigens of the outer layer of the tumor cells. Chemical analyses of the preparation showed that the mucopolysaccharide is composed of hexosamine, uronic, acid, hexose, and proteins. The mucopolysaccharide was shown to possess unique migration rate on electrophoresis and thin layer chromatography.
Eight patients with acute lymphosarcoma cell leukemia or acute lymphoblastic leukemia received infusions of plasma containing a lymphotoxic factor. The lymphotoxic factor induced a transient fall in the number of "blast" cell forms in the peripheral blood in six of the eight patients but did not produce sustained remissions. Previous investigations have demonstrated that this lymphotoxic factor, found in the plasma of patients with active multiple sclerosis, is of low molecular weight and does not have the properties normally associated with an antibody. This factor appears to selectively interfere with ribonucleic acid synthesis in the thymus-derived lymphocyte. Lymphotoxic factor activity was demonstrated in the serum of one patient during a remission in leukemia induced by a viral illness.
This study was initiated to evaluate the in vivo infectivity and pathogenicity of a group of recombinant feline leukemia viruses (rFeLVs) previously generated by in vitro forced recombination between a FeLV subgroup A virus (FeLV-A) and an endogenous FeLV (enFeLV) envelope (env) element (Sheets et al., 1992, Virology 190, 849-855). To determine infectivity of rFeLVs, neonatal cats were inoculated with rFeLVs alone or in combination with FeLV-A. The recombinant viruses were able to replicate efficiently in vivo only when administered along with FeLV-A. Of six co-infected cats, three developed thymic lymphosarcomas, one severe aplastic anemia, and two cachexia and depression; all were viremic and seroconverted shortly after inoculation. While both virus types were detected in virtually all tissues examined from these tumor-bearing cats, there was a particularly noteworthy sequence reversion in the rFeLVs. It is known that exogenous FeLV isolates carry a conserved neutralizing MGPNL epitope in the middle of the surface glycoprotein domain of the env gene. In contrast, the parental recombinant viruses used to inoculate these cats harbored the enFeLV-derived MGPNP sequence at this position. However, all in vivo-propagated recombinants displayed the MGPNL sequence, while the env-encoded backbone flanking the MGPNL sequence was that of the parental recombinant virus. These results suggest that viruses with the MGPNL epitope have an in vivo proliferative advantage. The data also provide an explanation for the conservation of this epitope in exogenous FeLVs despite the existence of variant forms in enFeLV proviral elements with which they can recombine.
A combined treatment modality imcorporating surgery plus BCG immunotherapy was administered to (C57Bl/6 X DBA/2)F1 mice grafted with EAkR lymphosarcoma. A single preoperative local or postoperative systemic BCG administration cured 20-30% of the animals, but did not prolong the survival time of these groups. Repeated s.c. injections of BCG resulted in a significant increase in survival time compared to the group submitted to surgery alone. In contrast, multiple i.v. injections of BCG before and after surgery were no more effective than surgery alone and were less effective than a single postsurgical i.v. injection in producing cures. We have concluded that for local BCG therapy, multiple injections before and after surgery are more effective than a single injection. However, for systemic therapy, multiple injections are less effective than a single injection applied postoperatively.
The categorization of lymphosarcomas with immune markers has enriched the prognosis value of the WHO classification. The prolymphocytic (centrofollicular) B-type and the null lymphoblastic subtype have a good prognosis, while the (T- or B-) immunoblastic type and the T-lymphoblastic subtype have a poor prognosis.
We have studied 24 cases of secondarily leukemic (stage V) lymphosarcoma (LS), 31 cases of "d'emblée" leukemic LS, and ten cases of lymphoid leukemic neoplasias transitional between "d'emblée" leukemic LS and chronic lymphocytic leukemia (CLL). These cases only concern the common types of the WHO classification of LS, i.e., the prolymphocytic, the lymhoblastic, and the immunoblastic. Some cases have also been classified by cell surface markers. The secondarily leukemic conversion occurred in 40% of the lymphoblastic types, in 14% of the prolymphocytic types, and in 17% of the immunoblastic types. It never occurred at stage I but could occur after any other stage. The mediastinal involvement was observed in three types, but most often in the lymphoblastic type. The prognosis after an acute lymphoid leukemia (ALL) treatment comprising active immunotherapy following chemo(radio)therapy is better for the leukemic prolymphocytic and lymphoblastic LS than for the immunoblastic type. Two patients (one of the lymphoblastic type) are in complete remission after 8 and 5 years, respectively. We have described ten cases of "d'emblée" leukemic LS with either large lymphoid or extra-lymphoid masses, bone marrow leukemic cell involvement, and LS aspects of neoplastic cells. Mediastinal abdominal, or other tumor masses are frequent. The prognosis for "d'emblée" leukemic LS following an ALL treatment is less favorable than ALL prognosis for patients of all ages including children. However, the first remission curve breaks at the 18th month and may form a plateau for about 30% of the patients of all ages. One patient has been in remission for more than 8 years after immunotherapy. We have also described ten cases of lymphoid neoplasia, whose cells cytologically and by the intensity of Ig secretion resemble leukemic prolymphocytic LS cells. However, the disease is more sensitive to CLL treatment than to LS or ALL treatment. Hence, there may be transitional conditions between leukemic LS and CLL. Finally, we have discussed the different possible frontiers between nonleukemic and leukemic LS and proposed two tests to detect the leukemic stage early: the systematic search for LS cells in the peripheral blood after concentration of nucleated cells by centrifugation and for cells carrying immune markers in the isolated mononuclear cell population of peripheral blood and the bone marrow.
A phase II trial of which preliminary results are available for 22 patients indicates that aclacinomycin applied in a continuous modality induced complete and partial remission in four of nine patients with acute lymphoid leukaemia that was resistant to all previously available drugs, and in four of eight patients with stage V lymphosarcoma (leukaemic). Bone-marrow toxicity was the major side-effect. Only one patient of 20 suffered from cardiac toxicity; no one had alopoecia. This very low incidence of myocardial lesions and the absence of hair loss had been predicted, respectively, by our electron microscope study of the myocardium and the light electron microscope study of the skin of golden hamsters [7], a test that detects frequent severe myocardium and skin toxicities for adriamycin and some anthracyclin analogues such as detorubicin, which was found to be toxic in a high percentage of patients in a clinical trial conducted by the E.O.R.T.C. Clinical Screening Group [8].
A patient with B-cell leukemic lymphosarcoma, whose lymphocytes had a monoclonal (IgM/D-L) surface immunoglobulin (SmIg) and formed rosettes with ox red blood cells (ORBC), is described. The leukemic cells were documented to have a monoclonal SmIg and cytoplasmic Ig (CIg) and secreted a monoclonal immunoglobulin (MIg) whose antibody activity was directed to the surface antigen of ORBC. Pretreatment of the leukemic cells with anti-mu, anti-delta, or anti-lambda inhibited E(ox) rosette formation specifically. Pretreatment of the leukemic cells with pronase removed the SmIg and abolished E(ox) rosette formation simultaneously, and regeneration of the SmIg was parallel with recovery of the rosette formation. A small amount of serum MIg could be detected by agarose gel electrophoresis and antiidiotypic antibody against the 19 S component of the serum revealed that the monoclonal SmIg, CIg, and serum MIg shared the same idiotope. This case suggests that lymphocytes of some B-cell malignancies may bind to ORBC through SmIg.
A mathematical model is presented to simulate the time-dependent uptake of methotrexate in spontaneous canine lymphosarcomas in vivo. Blood flow ratew in these tumors are high so that transport to the tumor is limited by cell membrane resistance. A significant amount of rapidly exchangeable methotrexate appears to exist in extracellular space loosely bound to proteins or cell membranes. Transmembrane drug transport follows Michaelis-Menten kinetics, wigh the maximum facilitated transport ranging from 0.002 to 0.007 mug/min/ml for the separate tumors studied and a Michaelis constant for transport equal to 0.2 mug/ml. This is in the range of Michaelis constants reported for normal tissues in rats in vivo and in several cell linnes in vitro.
A very high degree of specific dexamethasone binding to chromatin and a marked in vitro inhibition of RNA-synthesizing capacity of purified lymphoma cell nuclei was found to correlate closely with the very strong cytolethal effect of glucocorticoids on lymphoma cells (in this case neither B- nor T-cells) of a young patient, whose condition rapidly and unexpectedly deteriorated after a total dose fo 90 mg of Prednisone given during a two day period; and in spite of prophylactic antihyperuricaemia treatment, the patient subsequently died. In this case the amount of glucocorticoid bound specifically by lymphoma chromatin was about 400% larger than is normally found in chromatin isolated from normal human thymus cells in persons on this age. The in vitro inhibition of RNA-Synthesizing activity measured with the aggregate enzyme and with isolated nuclei from lymphoma cell-nuclei by dexamethasone correlates closely to the specific dexamethasone binding capacity of chromatin. Thus a better prediction of the therapeutic effect of such lymphosarcoma cells to glucocorticoid may be possible.
In a case with leukemic lymphosarcomatosis huge nucleoli developed at a final stage refractory to chemotherapy. The lymphosarcoma cells were characterized before and after their macronucleolar transformation by cell fractionation and by biochemical characterization of their nuclear 45S RNA fraction after high specific labelling with 32P-orthophosphate. The analyses provided evidence for a marked increase in nucleolar 45S RNA production. Processing of preribosomal RNA did not seem to be blocked. The biochemical alterations are discussed especially with respect to a possible significance of biological changes during the development of drug resistance against cytostatic agents.
A metastatic tumor population was isolated in BALB/c mice during routine s.c. passage of the colon 26 adenocarcinoma. The tumor metastasized to lymph nodes, liver, spleen, ovary and kidney. A primary culture established from the s.c. growing tumor was composed of both adherent and nonadherent cells. These two cell types were successfully separated from the primary culture and designated CMS (suspension cells) and CMA (adherent cells). The CMS and CMA cell lines are morphologically distinct in culture; however both formed similar histopathologic tumors when inoculated s.c. Furthermore, both tumor lines showed identical metastatic patterns in BALB/c mice with involvement of lymph node, liver, spleen, ovary and kidney. CMS and CMA expressed T-antigen as revealed by FITC-labeled-anti-Thy 1.2 antibody. Chromosome analysis and morphologic studies by light and electron microscopy indicated that the present metastatic lines have no relationship with the colon 26 adenocarcinoma and seem to be non-thymic T-cell lymphosarcomas which developed spontaneously in BALB/c mice.
With suitable treatment, the potential for long survival with gastric lymphoma is well-documented. However, since these tumors constitute only about 1-3% of gastric malignancies, they may occur only rarely in a particular radiologist's experience. The present report of a remarkable therapeutic response is a reminder that the possibility of lymphosarcoma should be included in the differential diagnosis of every gastric neoplasm.
An antiserum was raised in rabbits against a primary metastasizing lymphosarcoma (ML) of the hamster. This was made tumor-specific by absorption with normal hamster tissue extracts. Immunoglobulin-G was prepared and tested for its cytotoxicity towards cells derived from the primary tumor and its liver metastases. The ML-specific IgG was found to be 2--5 times more cytotoxic for cells derived from the primary tumor compared to cells obtained from liver metastases.
Treatment of cancer by the administration of interleukin-2 (IL-2) at the tumour site is a very effective approach. The mechanism of this tumour regression is not clear, although it is generally assumed that it involves an IL-2-stimulated immune reaction. There are, however, no immune parameters that consistently correlate with the therapeutic effect. We have studied the histopathological events in a subcutaneously (s.c.) growing SL2 lymphosarcoma (transplantation of tumour cells at day 0) treated with peritumoural IL-2 injections at days 10-14. Most IL-2-treated tumours had already begun to regress from day 12 onwards, showing that local IL-2 therapy was also effective in the present study. The immediate reaction after local IL-2 administration is vascular leakage from the surrounding circulation, causing oedema within the tumour and in a broad zone surrounding it. The presence of oedema is always accompanied by markedly increased tumour necrosis. After a few days extensive angiogenesis occurs at the border between the oedematous area and the healthy connective tissue. Leucocytes, mainly macrophages, migrate via the newly formed blood vessels to gain access to the necrotising tumour site, where they form a granuloma. These macrophages phagocytose the dead tumour material. During growth, the SL-2 tumours infiltrate the surrounding tissue. The infiltrating tumour strands are apparently attacked by macrophages, as the tumour cells in close proximity to the latter are progressively destroyed. Therefore, the body of the tumour and the infiltrating tumour strands are attacked in different ways. The primary effect of IL-2 administration at the tumour site is vascular leakage that causes oedema in and around the tumour. This is followed by extensive angiogenesis, with the resulting migration of white cells from the circulation, which form a granuloma around the tumour. Both the oedema and the granuloma cause tumour regression.
An ascitic lymphosarcoma (LS-A) of Swiss mice that regressed spontaneously on subcutaneous (s.c.) transplantation was investigated for the mechanism of its progressive growth and host mortality on intraperitoneal (i.p.) transplantation. In vitro studies indicated significant inhibition of LS-A proliferation seeded at higher cell density (>10(4)/ml). Culture supernatants of LS-A caused bi-modal growth effects, the early supernatants (24 h) caused stimulation and the late (72 h) supernatants inhibited LS-A proliferation. The 72-h supernatants also suppressed T and B cell response to mitogens in a dose-dependent manner. Pan anti-transforming growth factor-beta antibody abrogated the inhibitory effects of supernatants. The supernatants contained both latent as well as bio-active form of transforming growth factor-beta1 (TGF-beta1) as determined by ELISA. Mice bearing i.p. ascites tumor had elevated serum TGF-beta1, hemoglobulinemia, splenic lymphopenia, impaired response of the T cells to mitogen and reduced expression of transferrin receptor (CD71) on the bone marrow cells. However, mice which rejected s.c. transplants, did not show significant changes in these parameters. Our studies indicated profound influence of site of tumor growth on tumor progression and host immune system mediated by tumor-derived TGF-beta1. It is possible that human tumors which secrete TGF-beta1 may exhibit similar patho-physiological effects in the host depending on the anatomical site of the tumor.
Cyclophosphamide 1.5-2.0-fold increased activity of cathepsins B and L in tumor tissue of mouse lymphosarcoma LS and caused tumor regression. The effect was most pronounced on day 5 after treatment. Twofold treatment with a selective cathepsin inhibitor Ep-475 slightly stimulated tumor growth in control mice and significantly reduced the antitumor effect of cyclophosphamide. Lysosomal cysteine proteases cathepsins B and L are involved, but do not play a key role in TNF-alpha-independent apoptosis in LS cells induced by cyclophosphamide.