Acute Myeloid Leukemia (AML)

Diagnosis & Tests

• The doctor would initially conduct a thorough physical exam and check whether the liver, spleen, groin, neck and lymph nodes in the under arms are showing any kind of swelling.
• A CBC blood test would be ordered for finding out the complete blood count that evaluates the number of white and red blood cells and platelet count in the blood. Additionally, the blood sample is microscopically analysed to check for appearance of the cells and in determining the amount of mature cells and leukemia cells known as blasts. Though blood tests might show the presence but they mostly do not reveal the type of leukemia that is present.
• For further identification of the type of leukemia, a bone marrow aspiration and biopsy procedure is conducted by the haematologist (specialist in blood disorders) or oncologist (cancer expert) wherein a needle in inserted within a large-sized bone (generally the hip bone) and aspirating out a miniscule quantity of liquid bone marrow and a part of the sponge-like tissue present within the bone (biopsy). The procedure lasts for nearly twenty minutes. As soon as the biopsy and aspiration are acquired, the haematologist, oncologist or pathologist would microscopically scan the samples.
• Further studies like the peroxi-dase and/or immunophenotyping might be needed for corroborating the detection and revealing the precise subtype of AML.
• Additionally, a small quantity of liquid bone marrow is forwarded for special chromosome testing known as cytogenetics that can at times provide crucial data concerning the treatment and recovery prospects.

Acute Myeloid Leukemia Treatment:

Those having AML go through a wide-ranging preliminary work-up that includes:

• An evaluation of the history and a physical exam.
• Blood analysis.
• Cardiac testing.
• Aspiration of the bone marrow employing biopsy procedure.
• Immunophenotyping of the bone marrow.
• A specialized chromosomal test known as Cytogenetics.

This material helps the leukemia doctors and pathologist in coming to a conclusion about the exact subtype of AML subsequent to which treatment is initiated.

The AML treatment is known to vary according to the age, overall health condition during diagnosis and the outcome of the cytogenetics . Majority of the patients that are aged 65 years and lesser are suggested to go in for an autologous transplant as part of the preliminary consolidation treatment. Largely, characteristic AML treatment involves 3 phases, namely:

• First phase

  Induction chemotherapy.

• Second phase

  Consolidation chemotherapy that might involve stem cell transplantation.

One subtype of AML known as acute promyelocytic leukemia or APL has a distinctive biology and is cured in a different manner. This form of leukemia could be cured using a vitamin pill known as altransretinoic acid or ATRA alongside chemotherapy. Majority of the individuals have to endure several cycles of this treatment. At times, bone marrow transplantation is the preferable choice.

First Phase – Induction Chemotherapy

The objective of undergoing induction chemotherapy is for eradication of leukemia cells present in the blood and bone marrow and for inducing a remission. A total remission is described as one wherein there is no perceivable appearance of leukemia cells in the blood or bone marrow and normal blood count levels in the absence of transfusions.

Induction chemotherapy in those aged 65 years or lesser generally involves elevated dosages of ARA-C and daunorubicin chemotherapy. The medications are administered over a span of a 6-day period. Though side effects are anticipated to be quite severe, the necessary palliative care measures like transfusions, antibiotics course and medicines are provided for effectual allaying of those side effects.

Chemotherapy is generally administered over nearly 5-7 days. During majority of the times of hospitalization, patients are offered concentrated palliative care for protecting them during times of quite depleted blood counts, involving red blood cells and platelets transfusions for correcting anemia and averting bleeding. Antibiotics are employed for both averting and in treating bacterial and fungal infections. Further antibiotics course could be prescribed in case other infections surface.

Growth factors like G-CSF or Neupogen could aid in normalising the patient’s white blood cell count and might aid in averting the infections. The chemotherapy agents are additionally linked with total but impermanent loss of hair, oral sores and rashes noted on the throat and skin.

Other supportive approaches involve nausea averting and decreasing drugs, drugs for treating diarrhea, eye drops for preventing irritation and beverages rich in nutrients for improving the daily nutritional intake.

For this procedure hospitalization is required for 4-5 weeks. The patients are discharged from the hospital once the blood counts have normalised and there is proper bowel functioning. During the conclusion of the induction therapy, a bone marrow biopsy is conducted for verifying whether a total remission has occurred. Nearly 70-80% of cases are likely to achieve total remission. In case a total remission is attained, the patients are then given a gap of one treatment-free month for preparing for the subsequent second (consolidation) treatment cycle.

Second Phase – Consolidation Chemotherapy

With total remission achieved, further chemotherapy would be required for eradicating any remnant leukemia cells in the body. Consolidation chemotherapy comprises of:

• Further rigorous chemotherapy cycles.
• A bone marrow transplant employing the patient’s own bone marrow known as autologous transplant.
• A bone marrow obtained from sibling donor used in the transplant known as allogeneic transplant.

This form of consolidation therapy is given on the basis of subtype of the leukemia, the preliminary cytogenetics and the proficiency of the leukemia doctor and the medical center.

The second phase of treatment mostly would comprise of analogous chemotherapy medicines like drug ARA-C (cytarabine). The real number of the chemotherapy cycles needed in the consolidation chemotherapy and the requirement for stem cell transplant tends to differ in each case.

By and large, consolidation therapy has analogous toxicities like induction therapy and additionally needs intensive palliative care. In some centers, the consolidation treatments could be performed on an outpatient-basis, though majority of the patients are given treatment in the hospital that need 4-5 weeks of hospital stay. Largely, about 30-40% of cases needing consolidation chemotherapy get cured.

Those undergoing an autologous stem cell transplantation, the stem cells are accumulated following the culmination of the consolidation chemotherapy stage and as soon as their blood counts normalise. A method known as mobilization facilitates the amassing of the stem cells from the blood. In case the white blood cell counts are higher than 10,000 cells/uL, a big-sized IV catheter known as a Quentin catheter is introduced into one of the bigger veins present in the neck region. This catheter is joined to an ‘apheresis’ machine for segregating the blood into separate constituents allowing solely the white blood cells to be collected with the rest of the blood constituents transferred back to the patient. Every apheresis procedure consumes 4 hours, and 2-3 sessions are generally needed for collection of adequate amounts of stem cells.

After resolving the other toxicities and a collection of the stem cells being done, the patient could be discharged from the hospital. The stem cells are kept preserved in deep freeze for future utilisation. A one month’s treatment-free gap is given so that the patients could ready themselves for the high-dose chemotherapy and the stem cells to be re-infused.

High-Dose Chemotherapy and Stem Cell (Bone Marrow) Transplantation

Stem Cell or bone marrow transplantation is mostly suggested in both intermediate and low-risk AML. Autologous stem cell transplantation –employing cells taken from the patient’s own bone marrow subsequent to having attained total remission – emerges to be providing a cure in about 50-55% of the intermediate-risk AML cases.

This stage of treatment is imperative and quite risky and needs a month’s hospital stay. The purpose of this treatment is for utilizing much elevated chemotherapy doses for total obliteration of any remnant leukemia cells. The side effects are quite acute and the likelihood of death due to treatment-associated complications is about 2-5%.

The chemotherapy medicines comprise of Busulfan and etoposide that are administered over a span of 5 days. Subsequent to 2 days of chemotherapy, a re-infusion of the frozen stem cells via an IV catheter is done. The remaining part of the hospital stay comprises of waiting till the new growth of the stem cells and in this time period, palliative care is offered as required. As soon as the blood counts start showing improvement, and the other side effects have subsided, the patients might be discharged. Majority of the patients are able to resume normal day-to-day functioning within 3-6 months following transplantation.

The autologous stem cell transplantation is the chosen treatment among those having good or intermediary-risk cytogenetics. Those patients having bad cytogenetics are preferably treated with allogeneic transplantation.

Allogeneic transplantation

This procedure having cure rates of about 50-60% employs stem cells or bone marrow from a matching sibling. Though allogeneic transplantation has major complications and risks as compared to either chemotherapy or autologous transplantation and about 20-30% of the cases fail to survive in the initial 3 months of being treated. Hence, this is the last option and set aside only in more complex cases. About 20-25% cure rates are attained in poor-risk AML patients that are idyllically treated using allogeneic transplant in spite of its complications and risks. An unrelated donor might be sought from the NMDP or National Marrow Donor Program for those patients having poor-risk leukemia that do not have a matching sibling donor.

Trial Therapies

Mylotarg is the novel drug used in treating leukemia that merges an antibody that distinctively targets leukemia cells and then interleaves them with a toxin. This treatment is favourable as it doesn’t lead to hair loss, oral sores or gastrointestinal tract upsets. But this treatment tends to lead to protracted periods of diminished blood counts. Additionally, the likelihood of attaining a remission is not as effectual as compared to chemotherapy. Also, ancillary work is pending in order to ascertain the best task of this agent for treating AML.

Popularity: 25% [?]