Disorders of Growth and Cancer Flashcards
What can cause changes in cell growth?
Different stressors which cannot be dealt with by homeostasis. These stressors can be external (Physical, chemical, infections or nutrition) or internal (hormones, metabolism or immune response). Different adaptations include hypertrophy, atrophy, hyperplasia and metaplasia
Name causes of:
- Hypertrophy,
- Hyperplasia
- Atrophy
Hypertrophy - hormonal stimulation or increased physical demand
Hyperplasia (increase no. cells) - can be normal proliferation of endometrium or normal compensatory hyperplasia etc or pathological such as atypical endometrial hyperplasia
Atrophy - Loss of innervation, diminished blood supply, poor nutrition, decreased workload, loss of endocrine stimulation and aging
Define metaplasia?
Reversible change from one fully differentiated cell type into another. It is a form of adaptation to stress, the change in cell is usually able to withstand the stress better. Eg, GORD - stratified squamous epithelium is replaced by gastric columnar epithelium
Define neoplasm
- An abnormal mass of tissue with excessive growth and uncoordinated compared to adjacent normal tissue. (Not a tumour which means lump)
- New growth of tissue which is abnormal. Can be malignant or benign.
Describe the difference between benign and malignant neoplasms
- Benign neoplasm grows without invading adjacent tissue or spreading to distant sites. Usually well-circumscribed. Growth rate tends to be slow and there are few cells dividing.
- Malignant neoplasms invade surrounding normal tissue and can metastasis. Usually not well-circumscribed. Growth rate is fast and many cells undergo cell division. They have large nuclei which contain high content of DNA.
Describe the histology, clinical effects and treatment of benign and malignant neoplasms
Benign - Cells are well differentiated. Can cause local pressure effects, secrete hormones but rarely lead to death. Treatment is via local excision
Malignant - Poorly differentiated cells. Cause local pressure and destruction, distant metastases and inappropriate hormone secretion, often lead to death. Treatment includes local excision, radiotherapy, chemotherapy and/or supportive treatment
Define dysplasia?
- Disordered cell growth in which cells fail to fully differentiate but are non-invasive.
- Form of benign neoplasm which may progress to become malignant. (often abnormal epithelial cells or melanocytes).
- It is recognised by alterations in the appearance of cells (nuclei may become darker and larger)
What is a carcinoma in situ?
The most severe form of dysplasia. It if full thickness dysplasia extending from the basement membrane to the surface of the epithelium.
Therefore it is only applicable to epithelial neoplasms. If the lesion is no more advanced than this then risk of metastasis is 0 as there are no BVs or lymphatic vessels above the basement membrane.
Explain tumour grading
Low grade = well differentiate
Moderately differentiated
High grade = Poorly differentiated.
Relative differentiation = tumour grade
Absolute differentiation refers to the tumour cell phenotype
What are the names of benign and malignant epithelial tumours
- Covering epithelium (eg skin or squamous epithelium at surfaces) is papilloma or carcinoma.
- Glandular epithelium (Lining tubes or hollow organs) is adenoma or adenocarcinoma
- Epithelia forming solid organs (liver, kidney, thyroid, adrenal) adenoma or carcinoma of a specific type.
Name the benign and malignant tumours of connective tissue
Smooth muscle - Leiomyoma (of the uterus is most common) or leiomyosarcoma.
Skeletal muscle - Rhabdomyoma or rhabdomyosarcoma
Bone - Osteoma or osteosarcoma
Cartilage - chondroma or chondrosarcoma
Fibrous - Fibroma or fibrosarcoma
Blood vessels - Angioma or angiosarcoma
Adipose - Lipoma or liposarcoma
What are the benign and malignant names of the following tumours:
- Lymphoid,
- Haemopoeitc,
- Primitive nerve cells,
- Glial cells,
- Melanocytes,
- Mesothelium
- Germ cells
- Lymphoid - no benign, lymphoma (HL or NHL)
- Hemopoietic - No benign, leukaemia
- Primitive nerve cells - rarely benign, neuroblastoma
- Glial cells - No benign, glioma
- Melanocytes - pigmented naevi or malignant melanomas
- Mesothelium - no benign, mesothelioma
- Germ cells - Teratoma or malignant teratoma or seminoma
What are the modes of cancer spread?
- Local invasion,
- Lymphatic spread (early spread),
- Blood spread (late spread)
- Transcoelomic (serosal) spread (common with ovarian and gastric cancer)
Lymphatic spread it the initial mode of spread for what cancers?
- Carcinomas
- Melanoma
What is the initial mode of spread for sarcomas?
Blood, they rarely use a different mode to transport
