What does subcortical cystic change growth

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Carcinogenesis


・ Overview (5)

- initiation


- latency period


- PhD


- progression


- invasion and metastasis

Carcinogenesis
・ Initiation (3)

- Induction of DNA damage (↑ oncogene / ↓ tumor suppressor genes) by a genotoxic carcinogen (so-called initiators)


- The affected cell irreversibly transforms into a potential tumor cell which, however, does not yet grow in an uncontrolled manner


- DNA damage is not transferred to the daughter cells and can be corrected by DNA repair enzymes.

Carcinogenesis
・ Latency Period (1)

- Time between initiation and promotion

Carcinogenesis
・ Promotion (2)

- Cocarcinogens lead to an increase in the proliferation of the initiated cell


- DNA damage can be passed on to daughter cells

Carcinogenesis
・ Progression (1)

- As a result of clonal reproduction and expansion of the transformed cell, a malignant tumor develops with irreversible autonomy.

Carcinogenesis
・ Invasion and Metastasis (2)

- Due to the loss of the differentiation antigens on their surface, the tumor cells lose their “feeling of belonging”.


- detach themselves from the tissue association and settle in other tissues.

Benign tumors


・ Definition (4)

- locally limited


- grow slowly, displacingly and expansively


- Often surrounded by a connective tissue capsule that clearly separates it from its neighboring tissue and usually enables complete surgical removal.


- Infiltration of neighboring structures / systemic spread does not take place

Benign tumors
・ Differentiation (3)

- well differentiated (similar to the mother tissue)


- homologous tissue


- monomorphic cells (all cells have the same degree of differentiation)

Benign tumors
・ Cell changes (6)

- hardly any cell atypia
- Nuclei and cells monomorphic
- euploid DNA
- regular chromatin distribution
- real plasma-core-relation
- low mitotic activity

Malignant tumors


・ Definition (4)

- grow quickly


- can infiltratively and destructively grow into neighboring structures


- Can spread along conduction pathways, penetrate the lymphatic and bloodstream and form daughter tumors (metastases) away from their place of origin.


- can therefore only be completely resected in the early stages.

Malignant tumors


・ Differentiation (3)

- dedifferentiated (no resemblance to mother tissue)


- heterologous tissue (cells with different degrees of differentiation)


- "colorful cut surface"

Malignant tumors


・ Cell changes (9)

- numerous cell atypia
- nucleus and cells polymorphic
- polychromatic nuclei
- polyploid / aneuploid DNA
- irregular chromatin ("salt and pepper aspect")
- shifted plasma-nucleus ratio in favor of the nucleus (dyskaryosis)
- high mitotic activity with atypical mitotic figures
- crush artifacts (weakened cell cytoskeleton)
- Basophilia of the cytoplasm (accumulations of endoplasmic reticulum and ribosomes)

Semimalignant tumors


・ Definition (5)


- grow slowly


- but behave malignantly at their place of origin (can invasively and destructively penetrate their surroundings)


- metastasize only extremely rarely or not at all. - Histological uniform cell appearance, palisade-shaped cell arrangements and few mitoses.


- high tendency to recur after surgical removal.


(- e.g. basalioma or basal cell carcinoma)

Borderline tumors


・ Definition (1)

- Dignity cannot be clearly determined histologically


(- e.g. some thyroid adenomas)

Stages of tumor development


・ Overview (4)

- precancerous lesions



- Precursors of malignant tumors


→ Intraepithelial neoplasia (dysplasia)


→ leukoplakia


→ Carcinoma in situ (Cis)



- Malignant lesions


→ Microinvasive carcinoma (early carcinoma)


→ Metastatic / invasive carcinoma



- Tumor-like lesion

Precancerous lesions


・ Definition (1)

- Tissue changes that are associated with an increased risk of degeneration.

Precancerous lesions
・ Classification (2) (table)

- facultative precancerous diseases


→ Risk of degeneration <30%


→ long period of time between occurrence of the precancerous condition and degeneration



- obligatory precancerous diseases


→ Risk of degeneration> 30


→ short period of time between occurrence of the precancerous condition and degeneration

Intraepithelial neoplasia (dysplasia)


・ Definition (3)

- Potentially reversible tissue malformation that deviates from the original tissue at the histological and cellular level in response to chronic stimuli


- The fewer cell atypia, the lower the degree of intraepithelial neoplasia (and vice versa)


- High grade intraepithelial neoplasia represents a serious change and is therefore one of the facultative precanceroses.

Leukoplakia


・ Definition (4) (image)

- Focus-shaped change in the squamous epithelium, which leads to a whitish, non-wipeable change in the surface epithelium in response to chronic stimuli


- occurs mainly on the mucous membrane in the mouth and throat, esophagus, genitals and urinary bladder


- Histological characteristics are hyperkeratosis, excessive horn formation (nucleated horny scales), hyperplasia of the basal cell layer and possibly lymphocytic stroma infiltration


- If it is accompanied by dysplastic changes (evidence of cell atypia), it is one of the facultative precanceroses.

Carcinoma in situ (Cis)


・ Definition (3) (image)

- non-invasive malignancy (in situ) is limited and cannot yet metastases.


- histolopathologically a highly atypical epithelium


- no invasive growth (basement membrane is not broken, the tumor grows purely intraepithelially)

Microinvasive carcinoma (early carcinoma)


・ Definition (3)

- Invasiveness limited to the mucous membrane of the affected organ


- Since they have broken through the basement membrane, early carcinomas (e.g. carcinoma in situ) can metastasize.


- With timely treatment, very good prognosis

Tumor-like lesions


・ Definition (1)

- have the morphological appearance and behavior of a tumor, but do not arise from an autonomous new tissue formation (aka pseudotumor)

Tumor-like lesions
・ Epulis (3)


- Cell structure consisting of granulation tissue (= granular cell tumor), which arises as a reaction to chronic inflammation (inflammatory-reactive granuloma)


- develops in the gums and on the alveolar process


- tendency to relapse after extraction

Tumor-like lesions
・ Myositis ossificans (1)

- Osseous metaplasia of the BGW of the skeletal muscles, which arises as a reaction to chronic stress and appears as a rapidly growing “tumor”.