mixed phenotype acute leukemia, B/myeloid

Mixed Phenotype Acute Leukemia (MPAL), B/Myeloid: A Rare and Complex Blood Cancer

Mixed phenotype acute leukemia (MPAL) is a rare type of blood cancer that arises from the bone marrow. Specifically, MPAL, B/Myeloid refers to a subtype of this disease where the cancer cells exhibit characteristics of both B-lymphoid and myeloid lineages.

Characteristics of MPAL, B/Myeloid

• The cancer cells in MPAL, B/Myeloid express markers from both B-lymphoid and myeloid lineages, making it difficult to assign a single lineage of origin.
• This subtype accounts for approximately 4% of all cases of acute leukemia [4].
• The symptoms of MPAL, B/Myeloid are similar to those of other acute leukemias, including anemia, bleeding, and infection.

Diagnosis and Treatment

• Diagnosis of MPAL, B/Myeloid requires extensive immunophenotypic analysis to identify the specific markers expressed by the cancer cells.
• Treatment for MPAL, B/Myeloid typically involves a combination of chemotherapy, targeted therapy, and/or bone marrow transplantation, depending on the individual case.

References

• [1] BS George (2022) - Mixed-phenotype acute leukemia: A heterogenous group of leukemias
• [4] NP Awasthi (2019) - Mixed phenotype acute leukemia: A rare type of blood cancer
• [5] Definition of MPAL, B/Myeloid by a medical organization
• [7] O Wolach (2015) - Mixed-phenotype acute leukemia: A heterogeneous group of rare leukemias

Mixed phenotype acute leukemia (MPAL), specifically the B/myeloid subtype, presents with a combination of symptoms that can be challenging to diagnose. Here are some common signs and symptoms associated with MPAL-B/myeloid:

• Bleeding or bruising: Easy bruising, tiny red dots (petechiae) on the skin, and bleeding gums may occur due to a shortage of normal blood platelets [3].
• Recurrent infections: Frequent viral, bacterial, or fungal infections can happen because of a reduced number of white blood cells [3].
• Bone or joint pain: Pain in the bones or joints can be a symptom of MPAL-B/myeloid, likely due to leukemia cells crowding out normal bone marrow cells [6][9].
• Easy bruising or bleeding: This is another common symptom, which can be caused by a lack of normal blood platelets [3][9].

It's essential to note that these symptoms can also be present in other types of leukemia, making diagnosis more complex. A definitive diagnosis of MPAL-B/myeloid requires a combination of clinical evaluation, laboratory tests, and molecular analysis.

References:

[1] Context result 2 [3] Context result 3 [6] Context result 6 [9] Context result 9

To diagnose Mixed Phenotype Acute Leukemia (MPAL) with a B/myeloid lineage, several tests and exams can be performed.

• A physical exam and health history are typically the first steps in diagnosing MPAL. This includes assessing the patient's overall health, medical history, and symptoms.
• Bone marrow examination is also crucial in diagnosing MPAL. It involves collecting a sample of bone marrow from the hipbone or sternum using a needle. The sample is then examined for any abnormalities, such as an excess of immature white blood cells.

Immunophenotyping tests are also used to diagnose MPAL. These tests involve analyzing the markers on the surface of leukemia cells to determine their lineage and maturity. In the case of B/myeloid MPAL, these tests may include:

• Flow cytometry: This is a laboratory test that uses fluorescent dyes to detect specific proteins (markers) on the surface of leukemia cells. It can help identify the presence of both B-cell and myeloid markers in the same cell.
• Immunohistochemistry: This is a technique used to visualize the distribution of specific proteins (markers) within cells. It can be used to confirm the presence of both B-cell and myeloid markers in MPAL.

These tests are essential in confirming the diagnosis of MPAL with a B/myeloid lineage, as they help identify the specific characteristics of the leukemia cells.

References:

• [2] Mixed phenotype acute leukemia diagnosis​​ Tests and exams to diagnose mixed phenotype acute leukemia may include: Physical exam and health history. Bone marrow ...
• [8] Mar 15, 2022 — Health experts use an immunophenotyping method, known as flow cytometry , on blood or bone marrow samples to identify these markers on leukemia ...

Treatment Options for Mixed Phenotype Acute Leukemia (MPAL), B/Myeloid

Mixed phenotype acute leukemia (MPAL) is a rare and aggressive type of blood cancer that combines characteristics of both lymphoid and myeloid leukemias. The treatment approach for MPAL, specifically the B/myeloid subtype, involves a combination of chemotherapy, targeted therapy, and in some cases, stem cell transplantation.

• Chemotherapy: Chemotherapy is often used as an initial treatment to induce remission. The current treatment recommendation is an ALL-like induction regimen followed by allogeneic stem cell transplant (allo-sct) in the first complete remission [2][8].
• Targeted Therapy: Targeted therapy, such as dasatinib plus steroids and intrathecal chemotherapy, has shown excellent short-term results for older adults with MPAL [1].
• Stem Cell Transplantation: Stem cell transplantation may be a reasonable treatment consideration for some patients. Further study is needed to optimize the management of MPAL [4].

Additional Treatment Options

Other treatment options that have been explored or recommended for MPAL, B/myeloid include:

• Radiation Therapy: Radiation therapy may be used in certain cases, such as when there are specific symptoms or complications.
• Acute Myeloid Leukemia (AML)-type and Acute Lymphoblastic Leukemia (ALL)-type therapy approaches: These hybrid-type therapy approaches have been used to treat MPAL [5].

Current Recommendations

The current treatment recommendation for MPAL, B/myeloid is an ALL-like induction regimen followed by allogeneic stem cell transplant (allo-sct) in the first complete remission. However, further study is needed to optimize the management of this rare and aggressive disease.

References:

[1] O Wolach · 2015 · Cited by 183 [2] BS George · 2022 · Cited by 16 [3] Mixed phenotype acute leukemia treatment · Chemotherapy (“chemo”) · Stem cell (bone marrow) transplant · Radiation therapy · Targeted therapy. [4] KM Nix · 2017 — An ALL approach with stem cell transplant may be a reasonable treatment consideration for some patients. Further study is needed to optimize the managements of ... [5] Nov 2, 2023 — Typical treatments include acute myeloid leukemia (AML)-type, acute lymphoblastic leukemia (ALL)-type or hybrid-type therapy approaches. [6] by S Gurbuxani · Cited by 1 — Acute myeloid leukemia: Induction therapy in medically fit adults ... treatment · Clinical manifestations, pathologic features, and diagnosis of B ... [7] by E Orgel · 2020 · Cited by 44 — Hybrid indicates components of AML + ALL therapy (n = 2). Regimen 1 was prednisone, thioguanine, cytarabine, daunorubicin, vincristine, and ... [8] by BS George · 2022 · Cited by 16 — The current treatment recommendation is an ALL-like induction regimen followed by allogeneic stem cell transplant (allo-sct) in the first ...

The differential diagnosis for mixed phenotype acute leukemia (MPAL) with a B/myeloid lineage involves distinguishing it from other types of acute leukemias.

• Acute Lymphoblastic Leukemia (ALL): MPAL with a B/myeloid lineage can be distinguished from ALL by the presence of myeloid markers in the blasts, which is not typically seen in ALL [1].
• Acute Myeloid Leukemia (AML): Conversely, MPAL with a B/myeloid lineage can also be distinguished from AML by the presence of lymphoid markers in the blasts, which is not typically seen in AML [2].
• Biphenotypic Acute Leukemia: This condition should be distinguished from biphenotypic acute leukemia, which is characterized by the co-expression of B-lymphoid and myeloid lineage markers without a clear predominance of one lineage over the other [5].

In addition to these differential diagnoses, MPAL with a B/myeloid lineage can also be considered in the context of other conditions that present with mixed lineage features.

• Mixed Phenotype Acute Leukemia (MPAL): As mentioned earlier, MPAL is characterized by leukemic blasts that express both myeloid and lymphoid lineage markers. The presence of a B/myeloid lineage in MPAL suggests a specific subtype of this condition [4].
• T/megakaryocyte or T/myeloid lineages: In some cases, MPAL can also present with T/megakaryocyte or T/myeloid lineages, which can be challenging to diagnose due to the presence of t(3;3) [7].

Overall, the differential diagnosis for MPAL with a B/myeloid lineage requires careful consideration of these various conditions and their characteristic features.

References:

[1] BS George (2022) [2] S Gurbuxani (cited by 1) [4] K Takahashi (2018) [5] A Porwit (2015) [7] Y Jia (2022)