Tumor Markers Flashcards
What is oncology?
Oncology is the study of tumors
What is a tumor?
Also called neoplasm, it is a mass of tissue that is formed by an accumulation of clonal cells with abnormal growth control, that is, clonal expansion.
What are the two states of a tumor?
Benign (non-cancerous) or malignant (cancerous, invasive)
Can both tumor states cause disease?
Yes
What are tumor markers?
These are substances synthesized and released by tumor cells or that are produced in response to the presence of cancerous cells.
Where can tumor markers be present?
In blood, body fluids, on cell surface or inside cells
What is malignancy?
Malignancy is a cellular disease that changes the normal influences that control cell growth, differentiation, and proliferation
What do malignant cells do?
They divide without control and can invade or spread to nearby tissues, or distal systems for further colonization.
Through what body system does these malignant cells go and what is this called?
Through the bloodstream and lymphatic system. Metastasis
What is it called when a tumor is not malignant, do not invade nearby tissue and are still under some control?
Benign tumors
Is cancer malignant or benign?
Malignant. It included all malignant/invasive cells including the ones solid or hematologic in nature like lymphomas and leukamias
What causes malignant cells?
Genetic or environment or both
List the four stages of cancer
Induction phase
In situ phase
Invasive phase
Dissemination phase
Discuss the induction phase of cancer
This is the long lasting phase in which cells are exposed to some mutagen or teratogen that affects cellular genes, that is their mutation, deletion, gene rearrangement. Abnormal cell function and division begins but is not predominant
Discuss the in situ phase
Transformed cells develop into cancerous cells but the cells remain localized. Tumor begins to grow
Discuss the invasive phase
Abnormally proliferating cells multiply and invade the lymphatic or vascular system
At what stage are most cancers detected?
Invasive stage
Discuss the dissemination phase
Cancerous cells are found in distant sites. It is difficult sometimes I’m this stage to determine the origin or the cells. Often untreatable
How are tumor markers used for screening?
High sensitivity, moderate specificity.
Screening tool means if the test is positive, it is a red flag for further analysis. Does not always mean the pt has a tumor. When negative, there is high confidence pt doesn’t have tumor. Eg Pap smear
How are tumor markers used for diagnosis?
Used in symptomatic patients.
High specificity, moderate sensitivity
Some TM are highly correlated with the existence of certain kinds of tumor. Very few markers can be used for tumor or cancer diagnosis however
How are tumor markers used for monitoring?
Level of tumor markers can be correlated with tumor load. If tumor load is decreased after chemo, it shows as a decrease in tumor marker too. In such cases, tumor markers can be used as a monitor of tumor progression and response to therapy.
How are tumor markers used as detectors?
Used to find disease recurrence if it manifests
