What is T-Cell Lymphoma?

T-cell lymphoma accounts for about 10% to 15% of non-Hodgkin's lymphoma, a higher proportion in China. In 2008, the World Health Organization (WHO) classified T-cell lymphoma into different pathological subtypes: T-cell, NK-cell lymphoma / leukemia. It can be roughly divided into two categories: pre-T cell tumors and post-thymic T-cell lymphomas, which can be primary in lymph nodes, extranodal tissues or skin. Compared with invasive B-cell lymphoma, mature or peripheral T-cell lymphoma has a worse prognosis. However, anaplastic large cell lymphoma (ALCL) uses anthracycline-based chemotherapy regimens, such as the CHOP regimen, and its effectiveness is similar to DLBCL. PTCL originating from the innate immune system occurs in adolescents, and it is mostly extranodal involvement. The most common sites are skin and mucous membranes. Peripheral T-celllymphomas (PTCL) originating in other immune systems are more common in adults In humans, most are lymph node involvement, accounting for more than 2/3 of PTCL.

T-cell lymphoma accounts for about 10% to 15% of non-Hodgkin's lymphoma, a higher proportion in China. In 2008, the World Health Organization (WHO) classified T-cell lymphoma into different pathological subtypes: T-cell, NK-cell lymphoma / leukemia. It can be roughly divided into two categories: pre-T cell tumors and post-thymic T-cell lymphomas, which can be primary in lymph nodes, extranodal tissues or skin. Compared with invasive B-cell lymphoma, mature or peripheral T-cell lymphoma has a worse prognosis. However, anaplastic large cell lymphoma (ALCL) uses anthracycline-based chemotherapy regimens, such as the CHOP regimen, and its effectiveness is similar to DLBCL. PTCL originating from the innate immune system occurs in adolescents, and it is mostly extranodal involvement. The most common sites are skin and mucous membranes. Peripheral T-celllymphomas (PTCL) originating in other immune systems are more common in adults In humans, most are lymph node involvement, accounting for more than 2/3 of PTCL.

Chinese name

T-cell lymphoma

Pathological subtype

T cell, NK cell lymphoma / leukemia

Causes and common diseases of T-cell lymphoma

Skin T-cell lymphoma is one of the tumors with a poor prognosis worldwide. Skin ulceration and plaque formation can occur early, and it is easy to gradually expand and develop. Recent studies have shown that malignant T cells control the inflammatory environment, inhibit cellular immunity and anti-tumor responses, while forming a chronic inflammatory microenvironment that promotes their own expansion.

1. Primary cutaneous T-cell lymphoma Primary cutaneous T-cell lymphoma (CTCL) is a type of extranodal non-Hodgkin's lymphoma. The diseases caused by hyperplasia are composed of a group of diseases with different clinical manifestations, histological characteristics and prognosis. The routine diagnosis of CTCL is based on clinical manifestations and histopathological examination. However, due to the diversity and complexity of the disease, especially early cases and rare cases, the clinical manifestations are diverse. Pathological often requires repeated biopsies, and sometimes the disease is further developed before being diagnosed, leading to CTCL and benign lymphatic proliferation. Sexual or skin inflammatory diseases are difficult to distinguish. Dermal T-cell lymphoma (CTCL) is primary in the skin and is characterized by the monoclonal expansion of T lymphocytes, which can involve lymph nodes, bone marrow, and internal organs. CTCL is the most common type of primary cutaneous lymphoma. Mycosis fungoides (MF) and Sézary syndrome (SS) are the two main subtypes of cutaneous T-cell lymphoma.

2. Tumor inflammation-microenvironment

The tumor microenvironment is the cellular and molecular environment in which a tumor exists and continuously interacts with it. This microenvironment is very interesting because it plays a key role in regulating tumor cell survival and proliferation, promoting immune escape, and the development of therapeutic resistance. In the tumor microenvironment, inflammatory cells and pro-inflammatory cytokines are beneficial to tumor growth and development, and induce immune suppression in the body, thereby inhibiting the body's anti-tumor effect; on the other hand, tumor susceptibility is related to the body's own inflammatory cytokine genes Polymorphisms or deletions, or conditions where inhibitors of inflammatory factors are suppressed. Recent evidence supports that malignant T cells can control the inflammatory environment, inhibit cellular immunity and anti-tumor responses, and at the same time can form a chronic inflammatory environment to promote its own expansion.

3. Malignant inflammation of cutaneous T-cell lymphoma Skin T-cell lymphoma (CTCL) is characterized by the presence of malignant T cells in long-term inflammatory skin lesions. CTCL lesions can show different degrees of inflammation, gradually changing from early inert lesions to progressive advanced diseases, this process is accompanied by significant changes in the nature of tumor-related inflammation. This shift does not appear to be a phenomenon, but a key step in disease progression. In T cell-mediated inflammation, the excessive activation of T cells and the high expression of various pro-inflammatory factors in the inflammatory microenvironment lead to abnormal expression of oncogenes, which promotes the malignant transformation of T cells and the generation of tumor clones. However, there are few studies on the mechanism of T cell-mediated inflammation and T cell tumorigenesis. As we all know, the main way of the body's anti-tumor immunity is cellular immunity, and helper T cells (Th) play an important regulatory role. In recent years, the status of Th1 / Th2 cell subsets has become a research focus in tumor immunotherapy.

T cell lymphoma treatment principles

Except for ALCL and ALK-positive patients, the total effective rate (ORR) of PTCL using the CHOP protocol is 60% to 70%, but the 5-year survival rate (OS) is only 25% to 35%, and the progression-free survival rate ( PFS) is lower [2]. Therefore, many chemotherapy regimens have been derived based on the CHOP regimen, but patients' survival has improved little. For early patients, radiotherapy combined with chemotherapy is the first choice.

Pralatrexate is the first drug approved for relapsed / refractory PTCL. It is a folic acid antagonist and has a high affinity for reduced folic acid carrier (RFC). Early-stage clinical trials have confirmed the antitumor activity of prazotroxacin, and a phase II study has subsequently been conducted. 48 patients with lymphoma were enrolled, with an ORR of 31% and a CR of 17%. By subgroup analysis, the ORRs of B-cell and T-cell lymphomas were 10% and 54%, respectively. All 8 patients with CR were T-cell lymphoma, 6 of them had PR in PTCL, and 4 of them were negative for PET-CT. This shows that T-cell lymphoma has a greater benefit on pratafloxacin than B-cells.

Cutaneous T-cell lymphoma (CTCL) is a group of primary T-cell lymphoma that originates in the skin and can affect lymph nodes, bone marrow, and internal organs. Mycosisfungoides (MF) and Sézary syndrome (SS) are the two most common subtypes of CTCL. For early localized patients, local medication or physical therapy is often used, and patients with advanced disease who are refractory are mostly treated with systemic or combined therapy. Local medication and physical therapy play a significant role in the treatment of CTCL.