Benign Neoplasia & Tumor Characteristics (PDF)

Benign neoplasia including nomenclature and characteristics of Benign & Malignant Tumours Dr. Sunil Pazhayanur Venkateswaran Associate Professor, Department of Pathology...

Benign neoplasia including nomenclature and characteristics of Benign & Malignant Tumours Dr. Sunil Pazhayanur Venkateswaran Associate Professor, Department of Pathology [email protected] 09/05/2024;1:30-2:30pm Inspire Empower Elevate  Learning/Lesson outcomes At the end of this lecture, you should be able to: Define neoplasia. Discuss the aetiology, Pathogenesis, morphology and spread of benign and malignant tumours. Understand the concept of oncogenesis and molecular basis of neoplasia. Describe and explain tumour progression and metastasis. 2 Presentation Flow Introduction and epidemiology of Neoplasia 1 Terms used in cancer pathology 2 Pathogenesis of Neoplasia Benign vs Malignant neoplasms including metastasis 3 3  Definition-Neoplasia new growth “An abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after cessation of the stimuli which evoked the change”..........................WILLIS doesn't serve any func. Progressive, Purposeless, Pathologic, Proliferation of cells. Uncontrolled cell division 4  Epidemiology In the last 50 years, the overall cancer death rate in men has significantly increased, whereas in women, it has fallen slightly. The increase in men can be largely attributed to lung cancer. Cancer is the second leading cause of death globally and is responsible for an estimated 9.6 million deaths in 2018. Globally, about 1 in 6 deaths is due to cancer. Approximately 70% of deaths from cancer occur in low- and middle-income countries. Source: https://www.who.int/news-room/fact-sheets/detail/cancer 5 Cancer incidence and mortality 6 Malaysia in 2020 (Source- Globocan) 7  Geographic/environmental factors Stomach cancer: 7 to 8 times more in Japan than in United States. Skin cancers are more common in AUS/ NZ than in Iceland due to carcinogenicity of UV. Obesity and being Overweight also increase the risk of developing cancer. Around one third of deaths from cancer are due to the 5 leading behavioural and dietary risks: high body mass index, low fruit and vegetable intake, lack of physical activity, tobacco use, and alcohol use. Alcohol abuse alone increases the risk of carcinomas of the oropharynx, larynx, and oesophagus. Smoking: implicated in cancer of the mouth, pharynx, larynx, oesophagus, pancreas, bladder, kidney, lung. 8  Hereditary association of cancers Inherited cancer syndromes (autosomal dominant): Inherited predisposition indicated by strong family history of uncommon cancer and /or associated marker phenotype. a. Familial retinoblastoma involves retina suffix used for a rise tumors that from primitive cells, often seen in children b. Familial adenomatous polyposis ( FAP) of the colon -develops polyps in the colon - risk of colon cancer be her c. Multiple endocrine neoplasia( MEN) syndromes benign malignanttumor or of multiple endocrine organ associated with neoplastic lesions d. Neurofibromatosis types 1 and 2. 9 10 Hereditary association of cancers Autosomal Recessive syndromes of defective DNA repair Xeroderma pigmentosum Ataxia-telangiectasia Bloom syndrome Fanconi’s anaemia 11  Terms to understand Cancer is the common term for all malignant tumours. Neoplasia literally means ‘ new growth’ and the new growth is called as a neoplasm. Oncology is the study of tumours or neoplasms. Oncologist is the clinician who treats tumours. 12  Non-Neoplastic Proliferation Controlled & Reversible Hypertrophy – Size (P) Hyperplasia – Number 14) /change from 1 mature epithelium to another) Metaplasia – Change Dysplasia – Disordered to the development of cancer, where there's a -a precursor lesion disorder arrangement of the cells in the epithelium - the basement membrane is still intact  Neoplastic Proliferation Uncontrolled & Irreversible* Benign Localized, non-invasive. cusily thatsurrounds the tumor) cunable to invade the basement membrane capsule a fibrous tissue I Malignant (Cancer) basement membrane Spreading, Invasive. ↳) eventually metastasis  Pathogenesis of Neoplasia In nature I Non-lethal DNA damageI tumor starts from a single cell leading to uncontrolled cell division and further DNA mutation damage causing the tumour to acquire specific malignant becomes monoclonal characteristics. Multi-step theory of carcinogenesis  Pathogenesis of Neoplasia ⚫Normal → Metaplasia →(DNA damage) → Dysplasia → (DNA damage) → (DNA damage) Anaplasia→ (DNA damage) Infiltration → (DNA damage) → Metastasis I spread to other organs) Progressive DNA Damage – a feature of neoplasia.  Pathogenesis of Neoplasia Non-lethal genetic damage lies at the heart of carcinogenesis. Acquired Cusily from the environment (genel Inherited in the germ line Three classes of growth regulatory genes are the main targets of genetic damage. Proto-oncogenes, Cresults in the development cancer) Anti-oncogenes/Tumour suppressor genes and I they don't I developed, but rather control essentially suppress the tumor once it's cycle & prevents the cell tumors from developing Genes that regulate apoptosis 17  ifnot successful Molecular When oncogenes are activated & ·requires mutated allele requires mutation in both alleles abnormal cells basis of tumor suppressor genes are inactivated, allws to persist cells divide unregulated uncontrollably: cell & accumulate proliferation cancer tumor cells - benign (non-invasivetumor becomes malignant  For 3rd LO on Carcinogenesis: I T cell proliferation: I Altered differentiation - - latency: -time between the promotion phase & the onset of progression Progression -period of cell accum. - Proliferation of neoplastic cell line driven by accumulated genetic mutations & genetic instability ->malignant neoplasm  Non-neoplastic vs Neoplastic lencapsulated) enclosed usily by capsule by not a enclosed fibrous capsule- pipshe a Normal Adaptation Benign Malignant Non-Neoplastic Neoplastic (Polyclonal) (Monoclonal) 19  Non-neoplastic vs Neoplastic Normal Adaptation Benign Malignant breaks away from the basement membrace Non-Neoplastic Neoplastic (Polyclonal) (Monoclonal) 20  Benign/Malignant neoplasms All tumours, benign and malignant , have two basic components: 1. proliferating neoplastic cells that constitute their parenchyma. 2. supportive stroma made up of connective tissue and blood vessels. If hv a tumor that's you growing very quickly, it will still remains Fast growth → less stroma bcoz the stroma is not neoplastic in nature Less stroma → more necrosis ↳ lesser connective tissue ↳ fewer blood vessels 21  Benign neoplasms Designated by attaching the suffix –oma to the cell of origin.( e.g. fibroma, chondroma, lipoma). They are variably classified, some based on their cells of origin, others on microscopic structure, and still others on their macroscopic patterns. They do not invade adjacent tissues borders, nor do they spread to distant sites. 22  Benign/Malignant neoplasms Biological characteristics means how old the tumor cells /resemble the normal cell. If it resembles the normal cell, the tumor is said to bewell-differentiated /hallmark of all malignant tumours ✓ Differentiation and anaplasia microscopic -> means In thatbackwards malignant of anaplasia: you'll find cells tumours, that looks abnormal. view pleomorphism highnucleuscytoplasmicperchomas an I singingtiple nucleare ✓ Rate of growth -> I Benign tumor:grows malignant tumor:grows slowly rapidly ✓ Local invasion Benign tumor:do not to the capacity to -> invade adjacent structures -> malignant tumor: easily invade the structures nearby ✓ Metastasis Benign tumor doesn't -> Malignant -> tumor -> always metastasize, metastasize meaning it X spread to distant organs 23  Benign vs Malignant Slow growing Fast growing Capsulated Unencapsulated Non-invasive Invasive & Infiltrate Do not metastasize Metastasize Well differentiated I they Well to poorly differentiated ormagneofher I and de can either resemble the cell I often resemble the which which they originate cell from originate from the Add suffix “oma” eg. Fibroma Add suffix “Carcinoma” or - differentiated epithelial in nature: epithelial tissue “Sarcoma” If arises from mesenchymal tissue FEATURES BENIGN MALIGNANT Growth rate Slow Rapid Mitoses Imitosis) Few Many (atypical) Nuclear chromatin Normal Increased (Hyperchromasia) N:C Ratio Normal Increased Differentiation Well differentiated Well to poorly differentiated Local growth Expansive Invasive Encapsulation Present Absent Vessel invasion /Destruction None/ little Frequent/ much of tissue destruction destruction 25 Nomenclature: Cell of origin + Suffix Benign Malignant Suffix – oma fibrous tissue is a mesenchymal cell - so we'lluse the suffix?Sarcoma Carcinoma / Sarcoma Fibroma Fibrosarcoma Osteoma Osteosarcoma Adenoma (anythingorginates gas or from Adenocarcinoma Papilloma I finger-like projections:usily lined by squamous on grangiaronal epothelial Squamous cell carcinoma I Ican also be called as transitional cell carcinoma Chondroma examples of malignant tumors that might look like benign tumor Chondrosarcoma some /for blood ~arising from lymphoid tissue Exceptions: Leukaemia, Lymphoma, Glioma, Hepatoma, ~ not benign cancer Melanoma, Seminoma, etc. I hepatocellular ↳ another name for: from glial cell in brain carcinoma I ↑ hard to say if its benign - skin tumor malignanttumor arises in the testis (seminiferous tubules) or malignant - malignant melanorma  Nomenclature Epithelial neoplasms: (– oma / carcinoma) Adenoma:, which usually forms glandular patterns. Papilloma: derived from squamous/transitional cells producing microscopically or macroscopically visible finger-like or warty projections from epithelial surfaces. Gross description of a projection above a mucosal surface – Polyp (usually benign) 27  Nomenclature maglinant benign ↓ ↓ Mesenchymal neoplasms: (– oma / sarcoma) Derived from fibrous tissue – Fibroma / Fibrosarcoma Derived from bone – Osteoma / Osteosarcoma Derived from cartilage – Chondroma / Chondrosarcoma Derived from fat – Lipoma / Liposarcoma can be a derivation from:ectoderm, endoderm or mesoderm ↑ -can he derivative or I cell germ layer or all 3 germ cell layers Teratomas: more than one germ cell layer (dermoid cyst/cystic teratoma of ovary) 28  Lipoma Intestine This is a benign tumour arising from the adipose/fat tissue. 29  Meningioma -arises from meningo telial set  -green color as it's secreting bile -liver is a gland Hepatic Adenoma 31 This is a benign tumour arising from the liver. Comparison between a benign tumor of the myometrium (leiomyoma) and a malignant tumor of similar origin (leiomyosarcoma). 32 Polyp - Polyp Stalk I called as pedunculated polyp If it doesn't he a stalks called as:sessile polyp darker in color, showing evidence of displasia. Pre neuplastic in nature, can become cancerous Colonic Polyp  Cystic teratoma of the ovary - mushy, yellowish brown material -> sebacious material:sebum, other -monstrong fetus can grow inside a teratoma, tissues agrabhangsinm if it's possible blot this tumor arising from germ cells Osteosarcoma of the Femur big tumor extending outwards Fema tumor malignant 36  Hepatocellular carcinoma - satellite.odules  Well- differentiated adenocarcinoma loss of polarity: anaplasia - Note the glandular pattern of the tumour and the malignant nature of the cells  Poorly- necrosis differentiated necrosis carcinoma Note a lack of pattern of the highly pleomorphic malignant cells(blue arrow) and areas of necrosis(green arrow)  Metastasis This means the development of secondary implants discontinuous with the primary tumour. Not all cancers have equivalent ability to metastasize (e.g. basal cell carcinoma). The more anaplastic and the larger the primary tumour, the more likely is metastatic spread. However, extremely small tumours have been known to metastasize. 40  Pathways of spread Malignant neoplasms spread by one of the 3 pathways: 1. Seeding within body cavities/Transcoelomic spread etc: colon & the ovary - these 2 organs are located in the peritoneal cavity spread themayheisoff singer, a rule, 2. Lymphatic spread of most the carcinomas 3. Haematogenous spread Seeding of cancers: Neoplasms invade a natural body cavity. Carcinoma of colon- seeds into peritoneal cavity. Cancer of the ovary seeds the peritoneal surfaces. 41  Metastatic cascade IThesetumorcellsneeda surviveat I  E-cadherin helps protein to stick to the cell? To & metaphasize go into deeper part of the tissue Molecular basis of cancer -> causes cell to separate & break the the basement membrace & enter the blood vessel - metastasize  CT scan showing a metastatic adenocarcinoma in the liver from the colon -arising The where metastasis takes place: common organ -liver -lung - brain - bones  References  https://gco.iarc.fr/today/data/factsheets/populations/458-malaysia-fact- sheets.pdf  https://www.who.int/news-room/fact-sheets/detail/cancer  Robbins and Cotran Pathologic Basis of Disease, 10th Edition. By Vinay Kumar, MBBS, MD, FRCPath, Abul K. Abbas, MBBS and Jon C. Aster, MD, PhD.  Robbins Basic Pathology: with STUDENT CONSULT Online Access, 10e (Robbins Pathology) 10th Edition. By Vinay Kumar MBBS MD FRCPath (Author), Abul K. Abbas MBBS (Author), Jon C. Aster MD PhD (Author) 45  Thank you. For more information please contact: Insert Name Here: A/P Dr Sunil Pazhayanur Venkateswaran Designation: Associate Professor, Department of Pathology Contact Details: [email protected] IMU Education Sdn Bhd No. 126, Jalan Jalil Perkasa 19 199201005893 (237397-W) Bukit Jalil, 57000 Kuala Lumpur, Malaysia 603 8656 7228 Insert footnotes here (if any). Formerly known as International Medical University. imu.edu.my