1 / 39

Disorders of Growth

Disorders of Growth. Dr. Tarek Atia. Introduction:. Tumor: Swelling / new growth / mass Two types of growth disorders: Non-Neoplastic Secondary / adaptation due to other cause. Neoplastic. Primary growth abnormality. Non-Neoplastic growth. Neoplastic growth. Hypertrophy ----- Size

ronaldmthomas
Télécharger la présentation

Disorders of Growth

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Disorders of Growth Dr. Tarek Atia

  2. Introduction: • Tumor: Swelling / new growth / mass • Two types of growth disorders: • Non-Neoplastic • Secondary / adaptation due to other cause. • Neoplastic. • Primary growth abnormality.

  3. Non-Neoplastic growth Neoplastic growth • Hypertrophy ----- Size • Hyperplasia ----- Number • Metaplasia ------ Change • Dysplasia ----- Disordered • Uncontrolled & Irreversible • Benign • Localized, non-invasive. • Malignant (Cancer) • Spreading, Invasive.

  4. Pathogenesis of cancer:Smoke and Lung cancer

  5. Cancer Incidence • 1.4 million new cases of cancer / year • 565,000 deaths from cancer / year • Cancer is 2nd leading cause of death (after heart disease) • Most common cancers • Men: Prostate • Women: Breast

  6. Definitions: Neoplasm is a mass of tissue that grows excessively, and keeps growing even if you remove the stimulus that started it. • Genes involved in cancer transformation: • Proto-oncogenes. • Oncogenes • Tumor suppressor genes

  7. Proto-oncogenes • Proto-oncogenes are a group of genes that cause normal cells to become cancerous when they are mutatedas a result of exposure to chemicals, radiation, or other carcinogens. • Proto-oncogenes encode proteins that function to stimulate cell division, inhibit cell differentiation, and stop cell death. • Mutations in proto-oncogenes are typically dominant in nature, and the mutated proto-oncogene is called an oncogene.

  8. At the cellular level, only one mutation in a single allele is enough to trigger an oncogenic role in cancer development. • The chance that such a mutation will occur increases as a person ages.

  9. Oncogenes • An oncogeneis a gene that, when mutated or expressed at high levels, helps turn a normal cell into a tumor cell. • Many abnormal cells normally undergo apoptosis. Activated oncogenes can cause those cells to survive and proliferate. • Most oncogenes require an additional step, such as mutations in another gene, or environmental factors, such as viral infection, to cause cancer.

  10. Tumor suppressor genes • Tumor suppressor genes play a critical role in regulating cell division. When DNA damage is detected in a cell, some tumor suppressor genes can stop the cell from multiplying until the damage is repaired. • Also, specific tumor suppressor genes can stimulate cells with damaged DNA to under go "apoptosis". • When tumor suppressor genes don't function correctly, the cells with DNA damage continue to divide and can accumulate further DNA damage that can lead to the formation of a cancer cell.

  11. Nomenclature Neoplasm Benign Malignant adenoma angioma rhabdomyoma Carcinoma Sarcoma squamous cell carcinoma adenocarcinoma angiosarcoma rhabdomyosarcoma

  12. Classification of Neoplasms • Benign Tumor (-oma) • Adenoma (“adeno-” means gland-like) • Fibroma • Lipoma (“lipo-” means fat) • Malignant Cancer (carcinoma or sarcoma) • Adenocarcinoma • Fibrosarcoma (“sar-” means fleshy) • Liposarcoma • Leukemia and Lymphoma

  13. Basal Lamina Carcinoma vs Sarcoma EPITHELIUM => CARCINOMA Collagen MESENCHYMAL ORIGIN => SARCOMA fibroblasts blood vessels blood cells muscle adipocytes (fat) bone cartilage

  14. Nomenclature of tumors: Cell of origin + Suffix (Oma, Carcinoma & Sarcoma) • Fibroma: Fibrosarcoma • Osteoma: Osteosarcoma • Adenoma: Adencarcinoma • Papilloma: Squamous cell carcinoma • Chondroma: Chondrosarcoma

  15. Benign Tumors • Usually designated by adding “-oma” to cell type • Adenoma: benign tumor arising from glandular cells • Leiomyoma: benign tumor arising from smooth muscle cells • Chondroma: benign tumor arising from chondrocytes (cartilage)

  16. General characters of Benign Tumors • Small in size • Slow-growing • Non-invasive • Well-differentiated: like normal cells • Stay localized

  17. Malignant Tumors • Carcinomas: arising from epithelial tissue • Adenocarcinoma: malignant tumor of glandular cells • Squamous cell carcinoma: malignant tumor of squamous cells

  18. Sarcomas– arising from mesenchymal tissue • Chondrosarcoma – malignant tumor of chondrocytes (cartilage) • Angiosarcoma – malignant tumor of blood vessels

  19. Confusing Terms

  20. 2- Non-tumors that sound like tumors 1- Malignant tumors that sound benign • Hematoma – collection of a mass of clotting blood within tissue • Lymphoma • Melanoma • Seminoma • Mesothelioma 3- Names that seem to be not tumors • Nevus: benign tumor from melanocytes • Leukemia: malignant tumor from Bone Marrow

  21. Malignant tumours • Grading (Differentiation): How bad do the cells look? • Staging (Progression): Where has the cancer spread? Well differentiated Poor differentiated

  22. Grading Cancer

  23. Differentiation and Anaplasia • Differentiation = how much the tumor cells resemble their cells of origin • Well-differentiated– closely resembles normal counterpart • Moderately-differentiated– sort of resembles normal counterpart • Poorly-differentiated– doesn’t resemble normal counterpart • Benign tumors are usually well-differentiated • Malignant tumors can show any level of differentiation

  24. Characters of Malignant Tumors • Large in size • Fast-growing • Invasive • Irregular, larger nuclei • Poorly-differentiated • Irregular borders • Metastasize

  25. Characters of Malignant Cells • Pleomorphism: Different shape • Hyperchromatic: large nuclei • Irregular nuclear shapes • Lots of mitoses, and atypical mitoses (Abnormal mitosis)

  26. Anaplastic or malignant cells; Abnormal mitoses

  27. Rate of Growth • Malignant tumors grow faster than benign ones. • Poorly-differentiated tumors grow faster than well-differentiated ones. • Growth is dependent on: • Blood supply • Hormonal factors

  28. Local Invasion • Benign tumors • Stay where they are. • Can’t invade or metastasize. • Usually encapsulated. • Malignant tumors • Infiltrate, invade, destroy surrounding tissue. • Then metastasize to other parts of body. • Not encapsulated.

  29. Carcinoma in situ

  30. Invasive carcinoma

  31. Invasive carcinoma

  32. Metastasizing carcinoma

  33. Invasive Squamous Cell Carcinoma

  34. General characteristics Benign Tumors Malignant Tumors Large in size Fast-growing Invasive Irregular, larger nuclei Poorly-differentiated Irregular borders Metastasize • Small in size • Slow-growing • Non-invasive • Regular nuclei • Well-differentiated • Well-defined borders • Stay localized

  35. Benign vs. Malignant

  36. Metastasis Metastasis: development of secondary tumor implants in distant tissues Ways of tumors metastasize Seeding Lymphatic spread Blood spread Tumor Metastasis depends on: • Type of tumor • Size of tumor • Degree of differentiation of tumor

  37. Liver with primary tumor Liver with multiple metastases

More Related