Clinical Features Of Pre leukemia, Myelodysplastic Syndrome, NeuroLeukemia And Testicular Leukemia
Pre-leukemia And Myelodysplastic Syndrome
Four undermentioned groups of conditions fall under this category since they may develop into acute myeloid leukemia on follow up.
- Well defined hematological disorders such as plycythemia vera, idiopathic myelofibrosis, paroxysmal nocturnal hemoglobinuria, Fanconi’s anemia, idiopathic sideroblastic anemia, multiple myeloma and lymphomas.
- Genetic disorders like Down’s syndrome
- Primary malignancies such as those of the breast or ovaries when treated with cytotoxic drugs or immunosuppressants.
- The myelodysplastic syndromes.
It is not clear whether prophylactic therapy will prevent the emergence of acute leukemia and thereby change the natural history and therefore the treatment is symptomatic.
This disease is senn rarely in elderly subjects presenting as refractory anemia. The anemia is generally normocytic and normochromic. The marrow is hypercellular and all elements show hyperplasia. Dyserythropoiesis is evidence by nuclear atypia, megaloblastosis, ringed sideroblasts and mutinuclearity. Intercurrent infections are common and may be fatal. After variable periods (months to years) some develop acute myeloid leukemia. The underlying processes are not clear and therefore, various synonyms are used for this condition, eg, smouldering leukemia, pre-leukemia, oligoblastic leukemia, low percent leukemia and refractory anemia with excess blasts (RAEB). It is likely that this condition is the result of proliferation of an abnormal stem cell. When acute myeloid leukemia supervenes, antileukemic therapy is given but results are less satisfactory than in de novo cases.
Bone Marrow Transplant In Leukemia Cases
Bone marrow transplantation
Cases of acute leukemia not satisfactorily responding to drugs have shown very encouraging results with bone marrow transplantation. Acute myeloid leukemia in first remission and acute lymphatic leukemia in second remission are indications for bone marrow transplantation. The patient’s marrow is ablated by giving cyclophosphamide 50/mg/Kg intravenously for 2-3 days and total body irradiation. After this the donor marrow is infused. The marrow starts functioning within a few days. Bone marrow transplantation has been successful in effecting cure and prolonging life in the majority of patients.
Non-availability of drugs
It is a major problem in treating acute leukemic subjects in developing countries. Cyclophosphamide 1 g/m2 given intravenously weekly for 8-12 doses along with prednisolone 40 mg/m2/daily was found to produce remission in 66.7% of acute lymphatic leukemia and 45.8% in acute myeloid leukemia in adults. Maintenance treatment and neuroprophylaxis were the same as described earlier. Subjects tolerated this regimen better. This is not an ideal regimen. There is a great need to develop drug schedule to suit subjects of developing countries, especially Indian subjects.
Convulsion In Neuroleukemia
Enlarged Testes In Testicular Leukemia
Neuroleukemia And Testicular Leukemia
Neuroleukemia occurs in 50% of Acute Lymphocytic Leukemias (ALL) and 10-12% of Acute Myelocytic Leukemias (AML) cases, if neuroprophylaxis is not given along with initial therapy.
Pathological lesions include infiltration by leukemic cells, hemorrhage and demyelination. In addition, drug toxicity, late consequences of irradiation and occlusion of cerebral microcirculation due to leukostasis add to the total neurological picture. When the leptomeninges are infiltrated, CSF shows the presence of a large number of blast cells, rise in protein and increased pressure and this may be mistaken for meningitis. Neuroleukemia may manifest during remission, or this may even be the presenting symptom in some.
Clinical features may be those of meningitis raised intracranial tension with papilledema, stupor, coma, focal neurological symptoms like convulsions or paralysis, cranial nerve palsies, spinal cord or spinal root compression, or intracranial hemorrhage. Sometimes hyperviscosity syndrome develops because of very high leucocyte counts (above 200 X 109/liter- 200,000/cmm). Symptoms of cellular hyperviscosity include auditory and visual disturbances, ataxia, headache, profound lethargy and coma. Leucapheresis relieved these symptoms dramatically.
It is started after achieving remission and is a must in acute lymphatic leukemia. Intrathecal methotrexate in a dose of 10-12 mg/m2 should be given twice a week for a total of 6 doses. A single dose should not exceed 15 mg. An alternative is cytosine arabinoside 50 mg intrathecally given twice a week for 6 doses.
Another modality of treatment is irradiation over the CSF cisterns with a total dose of 2000 to 2400 rads over a period of 16-23 days. Treatment of established neuroleukemia is less effective. Cranial or craniospinal irradiation combined with intrathecal methotrexate or cytosine arabinoside is the method of choice.
The testes may be enlarged, firm and tender or the involvement may be clinically inapparent. Affection of the testes may occur before, during or after the induction therapy. Testicular involvement leads on to relapse. Treatment of testicular lesion is by irradiation with 1000-2000 rads over a period of 2-10 days. Prophylactic irradiation of the testes has been tried in some centers, but the high incidence of sterility limits its routine application.
© 2014 Funom Theophilus Makama