Neuplasm = abnormal and extensive autonomous growth of
tissue
- Derived from cells with a capacity to proliferate
- Stimuli responsible for uncontrolled proliferation may
not be identifiable
- Involvement of genes regulating cell growth, death or
repair
- Involvement of epigenetic factors
- May express varying degress of differentiation
Benign vs malignant tumors
- No invasion in adjacent tissue - Ability to invade in adjacent tissue
- No metastases - Ability to metastasize
Characteristics of benign tumors
- Usually well differentiated; resemble tissue of origin
- No infiltration in surrounding tissue, no metastases
- Disappear after resection
- No fatal outcome
o Anatomical position
o Excess hormone production
Characteristics of malignant tumors
- Do not resemble tissue of origin – cellular atypia
- Invasive growth
- Metastases
- Can regrow after resection
- Fatal outcome (without treatment)
Histologic diagnosis of malignancy
High degree of cellular atypia (anaplasia)
1. Variation in size and shape of cells an cell nuclei (pleomorphism)
2. Enlarged and hyperchromatic nuclei (clumped chromatin, prominent nucleoli)
3. Atypical mitosis
4. Bizarre cells (giant cells)
,High mitotic acitivity
Disorganized growth pattern (and often compromised blood supply)
Invasion into surrounding tissue
Metastases
Colon tumors – different degrees of differentiation
Tumor morphology
All tumors (benign and malignant) have 2 basic components:
1. Parenchyma (transformed or neuplastic cells)
a. Determines the behaviour of the tumor
2. Host derived non-neoplastic stroma (connective tissue, blood vessels and inflammatory cells)
a. Crucial to the growth of the neoplasm
CAF = cancer associated
fibroblast
MSC = mesenchymal stem cell
Cancer nomenclature – names of cancer
Location where the cancer originated (e.g. breast cancer, lung cancer, skin cancer)
- Even when metastasized to other parts of the body the cancer will keep its name
, Histological tissue type affected
- Epithelial origin
o Derived from ectoderm: epidermis, glands on skin
o Derived from endoderm: epithelial lining digestive tract, incl liver parenchyma,
epithelial lining respiratory tract, lungs, epithelium of bladder and urethra, glands
- Mesenchymal origin (embryonic connective tissue)
o Derived from mesoderm: muscle, bone, fat, cartilage
Some exceptions:
Leukemias: malignant neoplasm of hematopoietic cells (lymphoid or myeloid)
Lymphoma: malignant neuplasm of lymphoid cells/tissues
Glioma: Malignant tumor derived from non-neural supporting brain tissue
Melanoma: malignant tumor of the skin (melanocytes)
90% of human cancers are carcinomas, give 2 possible reasons:
Carcinoma heeft veel contact met de buitendwereld (UV en andere dingen) waardoor het sneller
malignent wordt
➔ Is ook veel differentiatie en dus meer kans op een fout
Angiogenesis is important for tumor growth
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller elinehamersma. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.32. You're not tied to anything after your purchase.