Neoplasia - Characteristics & Classification of Neoplasm Chhavi Singh
This power point presentation take a detail note on neoplasm (cancer), types of neoplasm, stages of neoplasm, various kinds of carcinogens. This presentation also take interest in the classification and characteristics of the tumor & difference between the normal cells and tumor cells.
Neoplasia - Characteristics & Classification of Neoplasm Chhavi Singh
This power point presentation take a detail note on neoplasm (cancer), types of neoplasm, stages of neoplasm, various kinds of carcinogens. This presentation also take interest in the classification and characteristics of the tumor & difference between the normal cells and tumor cells.
Dear all, Pathologybasics is out with a new series of power point presentations on general Pathology.. Following is link presentation on seventh and the most difficult to understand chapter of robbins.. chapter 7,neoplasia. Any suggestions/feedback/constructive criticism are welcome on facebook.com/pathologybasics or pathologybasics@gmail.com
Dear all, Pathologybasics is out with a new series of power point presentations on general Pathology.. Following is link presentation on seventh and the most difficult to understand chapter of robbins.. chapter 7,neoplasia. Any suggestions/feedback/constructive criticism are welcome on facebook.com/pathologybasics or pathologybasics@gmail.com
Neoplasia
Overview
Characteristics of neoplasms compared to normal tissues
Types of neoplasms
Benign vs malignant
Cellular differentiation
Genetic basis for neoplasia
What is a “neoplasm”?
Lay term of “tumor” conveys usual connotations – ie a new growth or mass
Definition revolves around these features:
Monoclonal proliferation of cells with specific mutations
Excessive and unregulated growth of these cells, often at the expense of surrounding normal tissue
Terms to know about when discussing neoplasia
Metastasis - spread of a malignant tumor from one site to another via blood or lymph
Benign – typically refers to those tumors incapable of metastasis and having a good clinical outcome (prognosis)
Malignant – those tumors capable of invasive growth and/or metastasis, often fatal if not treated effectively
Parenchyma – these are the tumor cells themselves, usually referring to epithelial cells in organs.
Stroma – connective tissue cells that support the parenchymal cells – not actually tumor cells, but are stimulated to grow by the tumor via growth factors, eg angiogenesis
Cellular differentiation
Tumors are often “graded” as to how closely they resemble the normal parent tissue that they are derived from.
Well-differentiated means the cells are very similar in appearance and architectural arrangement to normal tissue of that organ
Differentiation
“Poorly-differentiated” refers to tumors that show only minimal resemblance to the normal parent tissue they are derived from.
“Anaplastic” means the tumor shows no obvious similarity to it’s parent tissue, usually associated with aggressive behavior
So what??????
Differentiation often provides clues as to the clinical aggressiveness of the tumor
Tumors often lose differentiation features over time as they become more “malignant” and as they acquire more cumulative genetic mutations
Differentiation often predicts responsiveness to certain therapies, eg estrogen receptors and Tamoxifen in breast cancers
Benign
– circumscribed, often encapsulated, pushes normal tissue aside
Malignant
– infiltrative growth, no capsule, destructive of normal tissues
Classification of neoplasms
Epithelial tumors
Benign forms – adenoma , papilloma
Malignant forms – carcinoma, eg adenocarcinoma, squamous cell carcinoma
Mesenchymal tumors
Benign forms – fibroma, leiomyoma,
Malignant forms – sarcoma, eg fibrosarcoma, leiomyosarcoma
Classification continued
Tumors of lymphocytes are always malignant – called lymphoma
Tumors of melanocytes
Benign – nevus
Malignant - melanoma
Precursors of neoplasia
Hyperplasia
Metaplasia
Chronic inflammation
dysplasia
Metaplasia, dysplasia, neoplasia
28. Benign vs Malignant Tumor Characteristics Benign Malignant Morphology and Differentiation Well-differentiated appearance Structure similar to tissue origin Little or no anaplasia Usually some lack of differentiation Structure often atypical Variable degree of anaplasia Rate and pattern of growth Slow, progressive expansion Rare mitotic figures Normal-appearing mitotic figures Slow to rapid growth; erratic growth rate Mitotic figures often numerous Mitotic figures sometimes abnormal Local invasion No Invasion Cohesive and expansile growth Capsule often present Local Invasion Infiltrative growth Usually no capsule Metastasis No metastasis Frequent metastasis (definitive criteria for malignancy) Damage to human body Relatively smaller Relatively bigger Prognosis Good Bad
37. Staging of Malignant Neoplasms Stage Definition Tis In situ, non-invasive (confined to epithelium) T1 Small, minimally invasive within primary organ site T2 Larger, more invasive within the primary organ site T3 Larger and/or invasive beyond margins of primary organ site T4 Very large and/or very invasive, spread to adjacent organs N0 No lymph node involvement N1 Regional lymph node involvement N2 Extensive regional lymph node involvement N3 More distant lymph node involvement M0 No distant metastases M1 Distant metastases present
66. Immunohistochemistry (IHC) in Tumor Diagnosis Immunophenotypes of major groups of malignant tumors Tumor type CK VIM S-100 CD45 Carcinoma + - - - Sarcoma - + - - Lymphoma - - - + Melanoma - - + -
69. Specific Cytogenetic Abnormalities Determined in Tumors Tumor type Chromosomal changes Genes involved or fusion genes Follicular lymphoma t(14;18)(q32;q21) JH/Bcl-2 Mantle cell lymphoma t(11;14)(q13;q32) JH/Bcl-1 Synovial sarcoma t(X;18)(p11;q11) SYT-SSX1 Ewing ’ s sarcoma t(11,22)(q24;12) EWS-FL11 Follicular carcinoma t(2;3)(q13;p25) PAX 8 -PPAR γ
70. Cytogenetic investigations - Fluorescent in situ hybridization (FISH) - Identify chromosome rearrangement detecting specific DNA sequences with fluorescently labeled probe
71. Cytogenetic Changes of Lymphoma Determined by FISH FL diagnosed by FISH: IGH/BCL2 t(14;18)(q32;q21) MCL diagnosed by FISH: IGH/CCND1 t(11;14)(q13;q32)
93. Learning without thinking leads to confusion, thinking without learning ends in danger. 学而不思则罔 , 思而不学则殆 -Kong Zi Learning is like rowing upstream: not to advance is to drop back 学如逆水行舟 , 不进则退