T-cell prolymphocytic leukemia (T-PLL)
- Method:
- Anticoagulant:
- Recommendation:
- Method:
- Anticoagulant:
- Recommendation:
- Method:
- Anticoagulant:
- Recommendation:
- Method:
- Anticoagulant:
- Recommendation:
- Method:
- Anticoagulant:
- Recommendation:
- Method:
- Anticoagulant:
- Recommendation:
Based on the current guidelines and the current state of research, there are different diagnostic recommendations for patients with T-prolymphocytic leukemia. We have summarized the most important information on the classification and diagnostic methods at MLL. In addition, we provide further links to therapeutic approaches for T-prolymphocytic leukemia, so that you can inform yourself in more detail.
T-PLL: Classification
T-prolymphocytic leukemia is a very rare, usually aggressive malignant disease of the lymphatic system. It accounts for approximately 2% of all mature lymphocytic leukemias in adults over 30 years of age and is described by WHO as a distinct entity within the mature T-cell and NK-cell neoplasms (WHO 2022). To gain further insight into this very rare entity, any newly diagnosed T-PLL should be included in the German CLL Study Group (DCLLSG) registry study "Long-term follow-up of patients with CLL, B-PLL, T-PLL, SLL, T/ NK-LGL, HCL and Richter Transformation" (NCT02863692) at the University of Cologne for the purpose of systematic data collection.
T-PLL: Diagnostics according to consensus criteria of the international T-PLL study group
Differentially, T-PLL must be distinguished from other mature cell lymphomas. The diagnosis according to the criteria of the T-PLL International Study Group (T-PLL-ISG) (Table 1) can usually be made on the basis of cytomorphology and immunophenotype. Genetic testing can significantly support the diagnosis. T-PLL cells can be found in peripheral blood, bone marrow, lymph nodes, spleen, liver or skin. In routine clinical practice, peripheral blood is usually sufficient for confirming the diagnosis (Staber et al. 2019).
Table 1: Consensus criteria of the T-PLL-ISG (Staber et al. 2019)
A diagnosis of T-PLL can be made when either all three major criteria are met or the first two major criteria plus one minor criterion are met. |
|
Major criteria |
Minor criteria |
>5 x 109 /l cells with T-PLL phenotype in blood or bone marrow |
Abnormalities involving chromosome 11 (11q22.3; ATM) |
Detection of T cell clonality (by PCR for TRB/TRG or by flow cytometry) |
Abnormalities of chromosome 8: idic(8)(p11), t(8;8), trisomy 8 |
Abnormalities of 14q32 or Xq28 or expression of TCL1A/B or MTCP1 * |
Abnormalities in chromosomes 5, 12, 13, 22, or complex karyotype |
Involvement of T-PLL-specific site (e.g., splenomegaly, effusions) |
|
* Cases without TCL1A, TCL1B, or MTCP1 rearrangement or their respective overexpression are collected as TCL1-family negative T-PLL. |
T-PLL: Diagnostic methods and their relevance
T-PLL: Prognosis
The overall rather uniform unfavorable prognosis for patients and the rarity of T-PLL hinders the prospective validation of clinical or biological prognostic factors. In clinical practice, there are currently no validated prognostic factors that can be used as a basis for specific stratification and therapeutic decisions.
T-PLL: Therapy
The disease course of T-PLL can be divided into the asymptomatic "inactive phase" and the "active phase" with characteristic symptoms such as lymphadenopathy, leukocytosis, hepato- and/or splenomegaly. In the inactive phase, a prudent watch-and-wait approach with close monitoring is indicated. After 1-2 years, even initially inactive diseases transition to the active phase, which requires treatment. A detailed overview of therapeutic approaches is provided in the Onkopedia guideline T-prolymphocytic leukemia and by Gutierrez et al (Gutierrez et al. 2023).
Status: November 2023