Programmed death ligand 1 (PDL1), immune checkpoint protein expressed on activated immune cells and tumor cells.
Activated T cells, programmed cell death 1 (PD1) and B7-1 receptor and regulate the immune response and autoimmunity is linked to the limits koinhibitor factor.


PDL1 expression in Cancer, T-cell mediated anti-cancer adaptive immune resistance mechanism to prevent an immune response.

PDL1 (22C3), pembrolizumab is FDA approved supplemental forensic medicine for certain cancers description:

  • Non-small cell lung carcinoma (NSCLC)
  • Cervical squamous cell carcinoma and endocervical adenocarcinoma
  • Head and neck squamous cell carcinoma (HNSCC)
  • Esophageal squamous cell carcinoma (ESCC)
  • Triple negative breast cancer (TNBC)


PDL1 (22C3) in the region of the tumor-specific scoring are. PDL1 excessive/chronic autoimmune inflammation is an immune checkpoint protein that regulate the immune response to prevent. Normally active immune cells (e.g., antigen presenting cells and B cells) it is expressed. High levels of inflammation and cytokines in response to induklener can be expressed by the expression (IFNy)


CD8+ regulatory T cells surface receptors PD1 and B7 is connected. Inhibit T-cell activation and T cell depletion causes.
Cancers, as a mechanism to weaken the host antitumor immune response adaptive immune resistance PDL1 can express.

PD1/PDL1 blockade prevent selective inhibition of the axis of T cell and T cell-mediated tumor cell killing to reactivate it, is used as a therapeutic strategy in the treatment of multiple cancers.


PDL1 (22C3), human monoclonal antibody blocking PD1 is accompanying with the diagnosis of pembrolizumab. Pembrolizumab, tumors high expression of PDL1 (the ratio of the tumor-score ≥ 50%) have EGFR or ALK genomic tumor aberrations, and non-metastatic non-small cell lung carcinoma were treated previously with systemic chemotherapy for metastatic non-small cell lung carcinoma is indicated for the treatment of patients with.


Pembrolizumab, tumor PDL1 expression (showing the ratio of the tumor-score ≥ 1%) showing disease progression during platinum-containing chemotherapy and metastatic non-small cell lung carcinoma is indicated for the treatment of patients with.

  • Patients with EGFR or ALK genomic tumor aberrations , these deviations must have before taking pembrolizumab for disease progression.


KEYNOTE-158 according to the results of clinical trials in Previously Treated Patients with advanced stage cervical cancer for FDA approval of pembrolizumab ( Christoph F J Clin 2019;37:1470 )


KEYNOTE-052 based on clinical studies with cisplatin containing chemotherapy for locally advanced or metastatic urothelial carcinoma patients who are not suitable for FDA approval of pembrolizumab ( Christoph F Lancet 2017;18:1483 )


FDA, KEYNOTE-048 clinical studies ( Lancet 2019;394:1915 ) on the basis of recurrent or metastatic head and neck squamous cell carcinoma approval for pembrolizumab as first-line treatments for patients with gave.


KEYNOTE-355 according to the results of clinical trials in advanced/metastatic triple-negative breast cancer FDA approval of pembrolizumab ( F J Clin Christoph 2020;38:1000 )


KEYNOTE-181 based on clinical studies, locally advanced, recurrent or metastatic esophageal squamous cell carcinoma for FDA approval for pembrolizumab ( F J Clin Christoph 2020;38:4138 )


PDL1 PharmDX (22C3) test, that target the extracellular space of PDL1 mouse monoclonal anti-PDL1 using the Clone 22C3 immunohistochemical test.

  • Evaluation of tumor cells must be present for at least 100 live
  • Necrotic areas should be avoided without scoring
  • The degree of staining of any intensity (1+ to 3+) contributes to scoring
  • Scoring depends on the region of the tumor
  • Painting and immune cells (IC) and tumor cells (TC) components may be present in
  • Tumor cells
    • Only membrane staining should be evaluated
    • Includes partial or complete membrane staining
    • Cytoplasmic staining is not included
  • Immune cells
    • High N:C ratio because of membrane and cytoplasmic staining is usually indistinguishable
    • Therefore, both were included in both cytoplasmic staining of the membrane of inflammatory cells
    • Staining in lymphocytes and macrophages are counted only for
    • Neutrophils, eosinophils, and plasma cells not staining
  • The recommended control tissue: benign human tonsil

Non-small cell lung carcinoma (NSCLC)


The ratio of the tumor score (TPS) were evaluated using

  • The TPS, according to partial or complete membrane staining in the examples all live tumor cells (≥ 1+) is the percentage of tumor cells showing live
  • TPS ≥ %of the sample 1 and PDL1 expression TPS ≥ 50% should be considered to have a high PDL1 expression


Is divided into 3 levels:

  • TPS
  • TPS 1 TO 49%: PDL1 expression
  • TPS ≥ 50% and a high of PDL1 expression

Cervical carcinoma

The expression in the United positive points (CPS) is determined by using.

  • CPS PDL1 stained cells (tumor cells, lymphocytes, macrophages) of the total number of tumor cells is obtained by multiplying by 100 and dividing the number of live.
  • CPS ≥ 1 PDL1 expression of the sample should be considered to have
  • The denominator of the cells in the tumor that are directly related to invasive tumor cells and the response of all live mononuclear immune cells (lymphocytes and macrophages in the tumor and adjacent organs, supporting nests) includes; adjacent mononuclear immune cells, the cells in the same tumor area is defined as 20x.

CPS value > 100 may be, but the reported maximum value is 100

Are divided into 2 groups:

  • CPS
  • CPS ≥ 1: PDL1 expression

Head and neck squamous cell carcinoma (HNSCC)

The expression in the United positive points (CPS) is determined by using.

  • CPS PDL1 stained cells (tumor cells, lymphocytes, macrophages) of the total number of tumor cells is obtained by multiplying by 100 and dividing the number of live.
  • PDL1 expression (CPS ≥ 1), is used to report the patient's compliance to the primary treatment with pembrolizumab.
  • The denominator of the cells in the tumor that are directly related to invasive tumor cells and the response of all live mononuclear immune cells (lymphocytes and macrophages in the tumor and adjacent organs, supporting nests) includes; adjacent mononuclear immune cells, the cells in the same tumor area is defined as 20x.

Are divided into 3 groups:

  • CPS
  • CPS ≥ 1: PDL1 expression
  • CPS ≥ 20: PDL1 expression*

*The level of PDL1 expression CPS ≥ 20 might be of interest to the treating physicians, but first-line therapy does not determine eligibility for.


Esophageal squamous cell carcinoma (ESCC)

The expression in the United positive points (CPS) is determined by using.

  • CPS PDL1 stained cells (tumor cells, lymphocytes, macrophages) of the total number of tumor cells is obtained by multiplying by 100 and dividing the number of live.
  • CPS ≥ 10 PDL1 expression of the sample should be considered to have
  • The denominator of the cells in the tumor that are directly related to invasive tumor cells and the response of all live mononuclear immune cells (lymphocytes and macrophages in the tumor and adjacent organs, supporting nests) includes; adjacent mononuclear immune cells, the cells in the same tumor area is defined as 20x.

Are divided into 2 groups:

  • CPS
  • CPS ≥ 10: PDL1 expression

Triple negative breast cancer (TNBC)

The expression in the United positive points (CPS) is determined by using.

  • CPS PDL1 stained cells (tumor cells, lymphocytes, macrophages) of the total number of tumor cells is obtained by multiplying by 100 and dividing the number of live.
  • CPS ≥ 10 PDL1 expression of the sample should be considered to have

Are divided into 2 groups:

  • CHS
  • CPS ≥ 10

Urothelial carcinoma

The FDA's Oncologic Drugs Advisory Committee (ODAC) meeting (2021), followed by pembrolizumab certified indication platinum-containing chemotherapy are not suitable for the treatment of patients with locally advanced or metastatic urothelial carcinoma has not been updated for; this update due to pembrolizumab in patients with urothelial carcinoma to determine the appropriateness of the test is no longer PDL1 therapy is not indicated
 

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