Child with Cancer Flashcards
Pediatric Cancer Definition
A group of chronic diseases characterized by uncontrolled growth and spread of abnormal cells which, if not adequately treated, results in the death of the patient
What is Cancer?
Genetic mutation: permanent DNA alteration. Can be inherited or caused by external toxins
Genetic Mutation results in:
- lack of differentiation
- loss of contact inhibition
- unregulated growth
- cellular immortality
Cancer is Caused by…
abnormal cellular growth, altered cell begins to multiply as directed by the altered genetic structure of its DNA and the absence or inactivation of tumor suppressor gene
Cancer starts as a genetic mutation (something goes wrong at the DNA level). A result of a newly acquired mutation at the DNA level, beginning in a single cell. DNA mutation results in lack of cell differentiation, loss of contact inhibition, unregulated growth, and cellular immortality. all of these cause the clinical manifestations of the disease.
Lack of cell differentiation
cells remain immature and fail to do work of normal cell
Loss of contact inhibition
normal cells stop dividing when they come in contact with other cells, but cancer cells crowd out normal cells
Unregulated growth
cancer cells multiply out of control - lack feedback mechanism that normal cells have. Mechanisms that tell the cell to die or stop dividing
Cellular immortality
failure of apoptosis/intrinsic suicide program
What Causes Childhood Cancer
Unknown (in most cases)
Not anything anyone did (or failed to do)
Related to peak growth
Possibly related to environmental agents (electromagnetic fields, chemicals, pesticides, viruses)
Kids cells are already growing fast and this might contribute
Certain cancers are related to peak growth periods, and there is an association between certain types of cancers occurring at certain ages
Oncogenes
activated through mutation of a proto-oncogene that normally maintains cellular growth & control; once activated to oncogene, uncontrolled cell growth (primary characteristic of cancer cells) results. Have been identified in leukemia, lymphoma, & some solid tumors.
Tumor-suppressor Genes
Arise from genes that normally suppress cancer formation but have lost their suppressor function, leading to uncontrolled growth. Have been identified in osteosarcoma, rhabdomyosarcoma, leukemia, retinoblastoma, and Willms tumor
Children at Increased Risk for Cancer (4)
Genetic predisposition (down syndrome: leukemia. Li-Fraumeni syndrome, retinoblastoma gene)
Immunodeficiency: higher risk because cancer has to do with immune system (congenital/acquired, treatment-related)
History of cancer
Prior cancer treatment
Classification of Childhood Cancer
Childhood cancer is not a single disease, but a wide range of diseases that are classified into two broad subcategories:
1. Hematological malignancies (leukemias and lymphomas)
2. Solid tumors
Within these classifications, tumors are named based on the type of tissue and/or site that the cancer develops in.
Three germ layers
Developing embryo has 3 germ cell layers:
- ectoderm (outermost layer - skin, mouth, nose, and anus)
- mesoderm (middle layer- blood vessels)
- endoderm (inner layer - respiratory, GI)
All body tissues arise from one of the embryonal tissue layers
Most childhood cancers arise from which embryonic germ layers
and adult?
Mesoderm and Ectoderm
(tissues deep within body)
Often referred to in pathology reports.
Don’t see skin & bowel cancers in children
And adult cancers arise from the endoderm (tissues exposed to the environment)
