LGL Leukemia (large granular lymphocytic leukemia) is a rare, indolent form of leukemia, whose characteristic feature is the presence of large lmphocytes with granules in bone marrow biopsy specimens or in the blood (10-15%).
The large granular lymphocytes are considered to be "malignant" because they arise from the same clone of cells and proliferate without obeying proper restraints on their growth. The lymphocytes are of two types, cytotoxic T cells (CD8+CD57+) or natural killer (NK) cells, and their clonicity is confirmed by T-cell receptor (TCR) gene rearrangement studies.
Genetic mutations, usually STAT 3 mutations and 20q deletions, are typically seen in LGL leukemia patients when cytogenetic studies are performed.
The bone marrow may be normocellular (31%), hypercellular (56%), or hypocellular (14%). In some patients, there may be features of myelodysplastic syndrome (MDS).
In many patients, there may be few symptoms or no symptoms at all. However, some patients eventually become symptomatic. For example, patients may develop infections when their white blood cell count drops (neutropenia) and require treatment with antibiotics.
Other patients may develop anemia, with fatigue, tiredness, lightheadedness, and palor. Treatment, including bone marrow stimulation with Procrit or red blood cell transfusions, may be required.
Many patients are treated with immunosuppressive medications, because it is felt that the pathogenesis of LGL Leukemia involves autoimmune mechanisms. Approximately 30% of patients with LGL leukemia may have concomitant rheumatoid arthritis or some other autoimmune disorder.
Accordingly treatment with methotrexate, cyclosporine or cyclophosphamide (Cytoxan), has been used. While not curative, approximately 40-50% of patients typically have a reasonably good response to these drugs. Sanikemmu, SR, et al. "Clinical features and treatment outcomes in large granular lymphocytic leukemia (LGL leukemia)." Leuk Lymphoma 2018 Feb; 59(2):416-422.
Other treatments that are used, when methotrexate, cyclosporine or cyclophosphamide are either ineffective or stop working, include anti-thymosin globulin (ATG), Campath (anti-CD52), tofacitinib (Xeljanz), abatacept (Orencia), or splenectomy.
Both G-CSF and GM-CSF improve neutropenia in patients with LGL leukemia whose absolute neutrophil count (ANC) drops <500 and who develop recurrent or severe infections.
Reduced-intensity stem cell transplant (Mini-SCT)
An alternative option for older individuals that may not be able to tolerate the intensive pre-treatment with radiation and chemotherapy that a conventional SCT requires, is what has been called a "mini"-SCT. Mini-transplant patients are pre-treated with lower doses of chemotherapy, generally without radiation therapy, which they tolerate better. They then receive an infusion of donor stem cells from a compatible donor, which reconstitute the bone marrow with healthy stem cells that give rise to normal red blood cells, white blood cells, and platelets.
Mini-SCT has been successfully used to treat aplastic anemia, leukemia, myelodysplasia, myeloproliferative diseases, lymphoma, and multiple myeloma. Unlike conventional SCT, which essentially eliminates all lthe stem cells in the bone marrow, mini-SCT suppresses the bone marrow to allow healthy donor stem cells to reconstitute the bone marrow.
While there are still significant risks with the mini-SCT, it is an option for older patients that may not tolerate conventional bone marrow therapy.
Disability Benefits with LGL Leukemia
Whether you are eligible for long-term disability benefits under the Social Security Act (SSDI) and/or in accordance with an employer-based disability plan (ERISA), will depend on the stage of your LGL leukemia, the symptoms and functional limitations that you have, and the adequacy of the medical documentation in your medical record.
If you have LDL leukemia and are prone to repeated infections, by virtue of a low white blood cell count, then certain working environments (crowds, multiple-person offices) may be medically contraindicated, because of the risk of exposure to infection. If you require treatment with immunosupressive drugs or chemotherapy, side effects from those drugs may also restrict your ability to work.If you suffer from chronic anemia, with a hemoglobin level <10, and have tiredness, severe fatigue, weakness, light-headedness, and other related symptoms, your functional capacity may be "less than sedentary" (meaning you are unable to perform even a "desk job"), and your chances of a long-term disability benefit award should be favorable.