13. Characteristics of tumors

Page 1: Introduction to Tumors

  • Topic: Characteristics of tumors.

  • Course: Surgical Semiology, 3rd year

Page 2: Occurrence and Classification

  • Method of Occurrence:

    • Congenital

    • Acquired

  • Location: Anatomical location

  • Number:

    • Single (solitary)

    • Multiple

Page 3: Tumor Consistency and Area

  • Consistency:

    • Soft

    • Elastic

    • Firm

    • Hard (stone, wood)

    • Pasty

    • Fluctuant (fluid)

    • Gas

  • Area:

    • Smooth

    • Irregular

Page 4: Sensitivity and Margins

  • Sensitivity:

    • Painful:

      • Spontaneously

      • Caused (touch)

    • Painless

  • Margins:

    • Linear

    • Curves

  • Dimensions: Measured in mm or cm (dimensional)

  • Form: Reported in figures and geometrical shapes

Page 5: Limits and Skin Changes

  • Limits:

    • Narrowly defined (better)

    • Vaguely delimited (bad)

  • Skin:

    • Unchanged

    • Modified (color, skin folds, hair growth, ulcers)

  • Mobility:

    • Mobile

    • Immobile (fixed)

  • Locoregional Adenopathy:

    • Absence

    • Presence-character

Page 6: Tumor Ulceration

  • Ulceration:

  • Location:

    • Reported to the topographic anatomical region

    • Reported to the tumor:

      • Central

      • Peripheral (excentric)

  • Number:

    • Single

    • Multiple

Page 7: Tumor Characteristics

  • Area:

    • Smooth

    • Irregular

  • Walls (sides):

    • Lines

    • Abrupt

  • Bottom Covered by:

    • Secretions (saliva, blood, milk, pus)

    • Crusts

    • Cellular debris

Page 8: Neoplasia Overview

  • Institution: Universitatea de Medicina Farmacie, Științe și Tehnologie George Emil Palade din Târgu Mureș

Page 9: Global Impact of Tumors

  • Context: Tumors are prevalent globally.

  • Statistics: In developed countries, malignant tumors are leading causes of death.

  • Challenges: Despite advancements in oncology, morbidity and mortality from malignant tumors are rising.

  • Contributors: Air pollution, stress, obesity, unhealthy lifestyles, and an aging population.

Page 10: Definition of Neoplasm

  • Definition: A neoplasm is an abnormal mass of tissue, characterized by uncontrolled growth exceeding that of normal tissue and persisting despite cessation of facultative stimuli. (Dr. R.A. Willis)

Page 11: Molecular Basis of Neoplasm

  • At Molecular Level:

    • Disorder of growth regulatory genes.

    • Activation of proto-oncogenes and inactivation of tumor suppressor genes.

    • Develops in multistep fashion, leading to genetic changes varying among neoplasms of the same histological type.

Page 12: Features of Neoplasm

  • Characteristics:

    • Excessive cellular proliferation

    • Lack of responsiveness to regulatory control mechanisms

    • Independence from continuous stimulus presence.

Page 13: Structure Characteristics of Tumors

  • Appearance: The gross appearance of tumors varies and relates to histogenesis, site, and biological behavior.

Page 14: Gross Appearance of Tumors

  • Shape:

    • Polypoid

    • Papillary

    • Nodular

    • Lobulated

    • Cystic

    • Fungating

    • Ulcerated

Page 15: Color of Tumors

  • Tumor Color: May indicate characteristics of different tumors (examples: lipoma, hepatocellular carcinoma).

Page 16: Tumor Composition

  • Components:

    • Parenchyma: Made up of proliferating neoplastic cells; determines tumor behavior and classification.

    • Supporting Stroma: Composed of connective tissue, blood vessels, and possibly lymphatics.

Page 17: Supporting Structures of Tumors

  • Components:

    • Parenchyma

    • Supporting stroma

Page 18: Tumor Nomenclature

  • Principle: Neoplasms are named using a binomial system denoting their histogenic origin and biological behavior.

Page 19: Classification of Tumors

  • Benign Tumors: End with “~oma” (e.g., fibroma, lipoma).

  • Malignant Tumors: End with “~carcinoma” or “~sarcoma”.

Page 20: Types of Tumors (Examples)

  • Benign: Thyroid adenoma, colonic adenoma, fibroadenoma of breast, leiomyoma of uterus.

  • Malignant: Adenocarcinoma of colon, hepatocellular carcinoma, squamous cell carcinoma.

Page 22: Differentiation and Anaplasia

  • Definition: Tumor differentiation denotes the extent to which a neoplastic cell resembles mature normal cells morphologically and functionally.

Page 23: Benign vs. Malignant Tumor Differentiation

  • Benign Tumors: Usually well-differentiated, resembling normal counterparts.

  • Malignant Tumors: Exhibit varying degrees of differentiation; undifferentiated cells labeled as "anaplastic" (no resemblance to normal tissue).

Page 24: Understanding Anaplasia

  • Definition: Lack of differentiation; does not represent reverse differentiation of normal cells but indicates a regression in differentiation.

Page 25: Growth Patterns

  • Tumor Growth Rates: Varies greatly; crucial for distinguishing benign from malignant.

  • General Rule: Higher growth rates correlate with increased malignancy.

Page 26: Benign Tumor Growth Characteristics

  • Benign Tumors: Grow as cohesive masses; localized, slow growth; often develop a fibrous capsule, allowing for easy excision.

  • Surface Growth: Tumors may grow away from epithelial surfaces, forming polypoid structures.

Page 27: Example of Benign Tumor

  • Lipoma: Example of a benign lipoma on small intestine's serosal surface, characterized by well-circumscribed and slow growth.

Page 28: Malignant Tumor Growth Characteristics

  • Malignant Tumors: Infiltrate, invade, and destroy surrounding tissue; lack well-defined cleavage planes.

  • Initial Stages: May form protrusions but will eventually invade normal tissue.

Page 29: Example of Malignant Tumor

  • Squamous Cell Carcinoma: Example of lung cancer showing invasive characteristics along bronchi.

Page 30: Comparison of Tumor Types

  • Hepatic Adenoma vs. Hepatocellular Carcinoma: Demonstrates differences in well-demarcation, consistency, and the setting of the tumor.

Page 31: Understanding Metastasis

  • Definition: Formation of a secondary neoplastic mass through transfer of neoplastic cells from the original tumor.

Page 32: Routes of Metastasis

  • Methods:

    • Lymphatogenous Metastasis: Common for carcinomas; sarcomas may also use.

    • Hematogenous Metastasis: Typical for sarcomas but may occur in carcinomas.

    • Body Cavity Metastasis: Direct seeding into cavities (e.g., peritoneum, pleura).

Page 33: Characteristics of Tumors

  • Comparison:

    • Differentiation: Well differentiated (benign) vs. range from well differentiated to undifferentiated (malignant).

    • Growth Rate: Slow (benign) vs. rapid (malignant).

    • Type of Growth: Expansive (benign) vs. infiltrative (malignant).

    • Separation from Tissues: Encapsulated (benign) vs. poorly separated (malignant).

    • Metastasis: No (benign) vs. yes (malignant).

Page 34: Precancerous Lesions

  • Definition: Abnormality in tissue that is one step away from cancer; not all become malignant.

  • Importance: Recognizing precancerous lesions can allow for surgical excision, which is often curative.

Page 35: Understanding Dysplasia

  • Definition: Abnormality in differentiation and maturation characterized by increased nuclear size, hyperchromatism, and abnormal chromatin distribution.

Page 36: Carcinoma in Situ

  • Definition: An epithelial neoplasm with malignant features that has not yet invaded through the basement membrane, allowing for curative excision if detected early. Significant in population screening programs.