neoplasia 1 pre lab lectures
TRANSCRIPT
Pre-Lab LectureDr. Renan
Neoplasia / “New Growth”
Abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persist in the same excessive manner after the cessation of stimuli, which evoked the change.
Fundamental to the origin of all neoplasms are heritable or genetic changes that allow excessive and unregulated proliferation that is independent of physiologic growth regulatory stimuli.
Oncology
The study of tumors
Benign Tumors Gross and microscopic
features are relatively innocent
Remain localized Cannot spread to other
sites Amenable to local surgical
removal Patient generally survives
Malignant Tumors Referred to as cancers Can invade tissues Can destroy adjacent
structures Spread to distant sites:
Metastasize to cause death.
Basic Tumor Components
Parenchyma Made up of transformed
neoplastic cells Largely determines the
tumors biological behaviorStroma
The supporting, host derived, non-neoplastic portion of the tumor.
Made up of connective tissue, blood vessels, host-derived inflammatory cells.
Provides support for the growth of parenchymal cells, carries blood supply.
Nomenclature
Benign Tumors Designated by attaching
the suffix: OMA to the cell type which the tumor attaches.
Ex: Fibroma – benign tumor
arising from fibrous tissue.
Chondroma – benign cartilaginous tumor
Adenoma – applied to benign epethial tumors producing gland patterns and neoplasm derived from glands.
Papilloma – composed of papillary structures.
Exceptions:o Lymphomao Mesotheliomao Melanomao Seminomao Hepatomao Dysgerminoma
Sarcoma Malignant neoplasm
arising from mesenchymal tissues or its derivatives
Ex: Fibrosarcoma –
malignant tumor of fibrous tissue origin.
Chondrosaroma – a neoplasm composed of malignant chrondocytes.
Carcinoma
Malignant neoplasm of epithelial cell origin.
Ex: Adenocarcinoma –
carcinomas that grow in a glandular pattern,
Squamous Cell Carcinoma – produce’s squamous cells.
Designated based on organ or tissue of origin.
o Renal Cell Carcinoma – kidneys
o Cholangiocarcinoma – bile ducts.
Mixed Tumors
Pleomorphic Adenomas (Salivary Gland) / Benign Mixed Tumor
Epithelial elements on a fibromyxoid stroma
Mesenchymal elements: islands of cartilage or bone.
Fibroadenoma (Breast) Proliferation of ductal
epithelial elements (adenoma_ Loose fibrous stroma
(Fibroma)
Teratoma Tumors containing mature of
immature cells representative of more than one, sometimes all three germ layers
Normally present in ovary or testis, sometimes in sequestered midline embryonic rest.
Should not be confused with mixed tumors.
Harmatoma A malformation that presents
as a mass of disorganized tissue indigenous to a particular site.
Choristoma A congenital anomaly
composed of heterotropic rest of cells, presenting as mass or nodule. (normal tissue in abnormal locations/site)
Ex: A small nodule of well developed and normally organized pancreatic tissue may be found in the submocusa of the stomach or duodenum.
Characteristics of Benign and Malignant Tumors
Differentiation Refers to the extent to which
the parenchymal cells resemble their normal forebears morphologically and functionally.
Desmoplasia
Stromal reaction induced by the tumor, producing a dense, abundant fibrous stroma.
Tumor Differentiation
Well Differentiated Closely resemble normal
counterparts. Retains the functional
capabilities found in normal counterparts.
Moderately Differentiated Some of the above criteria are
retained and can also be like normally resembling the normal counterparts.
Poorly Differentiated Do not resemble normal
counterparts. Looks primitive, disorganized
and immature.
(Squamous cell carcinoma)
Keratin pearl – automatically categorizes a tumor as well differentiated type. Anaplasia
“To form backward”. Dedifferentiation or loss of the
structural and functional differentiation of cells.
Hallmark for malignancy.
Pleomorphism Marked variation in size and
shape
Hyperchromasia Large, darkly staining nuclei
(increase in DNA)
Increased Nuclear to Cytoplasmic Ratio
Normal NC ration 1:4 to 1:6
Tumor Giant Cells One enormous nucleus or
several nuclei. Large/Prominent Nucleoli. Coarse and Clumped
Chromatin.
Presence of Abnormal Mitosis
Tumor Giant Cells characteristic of metastatic neoplasm
Atypical Mitosis (Tripolar form)
Loss of Polarity
Failure to develop recognizable patters of orientation to one another.
“Polarized” – nucleoli are only oriented to one direction.
Dysplasia
o Loss in the uniformity of individual cells and their architectural orientation in the epithelium.
o Disorderly but not neoplastic proliferation of cells.
o Exhibit pleomorphism, possess large, hyperchromatic nuclei.
o More abundant mitotic figures than usual, appearing in abnormal locations within the epithelium
“All anaplastic cells are dysplastic but no all dysplastic cells are anaplastic”
Carcinoma in Situo Dysplastic changes are
markedo Involvement of the
entire thickness of the epithelium
o Pre- invasive cancer
Invasion
Benign Tumorso Well-circumscribed and
remain localized at their site of origin.
o Does not have the capacity to infiltrate. invade of metastasize
o May be encapsulated or unencapsulated.
Malignant Tumorso Poorly circumscribedo Grow by progressive
infiltrationo Invade, destroy and
penetrate the surrounding
Metastasis Identifies a neoplasm as
malignant The most reliable feature that
distinguishes malignant from benign tumor.
The more anaplastic and larger the primary neoplasm, the more like is the metastatic spread.
Pathways
Seeding within the body cavities Typical of ovarian cancers /
most common in the peritoneal cavity
Lymphatic spread Typical of carcinomas
Hematogenous spread Typical of sarcomas
Simple Tumors Tumors of mesenchymal origin
o Connective tissues and derivatives
Fibrous tissues Fibrous and
Histolytic Fatty tissue Bone
o Endothelial and related tissues
o Blood cells and related cells
o Muscle
Tumors of Epithelial Origin
Spindle in shape with blond nuclei –benign
Interlacing fascicles of fibrous tissues, no hemorrhage, necrosis and mitotic figures.
Cells (nuclei) are pleomorphic, hyperchromatic and coarse pattern of chromatic, prominent nuclei, increased NC ratio.
“Adipose tissue”, prominent in the back and extremities.
Nuclei are confined the periphery rendering the appearance of singlet ring.
Histogenetic origin – MesenchymeCell Origin – adipocytes
Benign Tumor of the bone
Benign osteocytes rimming the forming bone
Presence of bone erosion, tumor invaded the bone and bone marrow.
Presence of hemorrhage.
Tumor giant cells with multiple nuclei
Endothelial & Related Tissue Blood Vessels Lymph Vessels
2 Types of Hemangioma Capillary Hemangioma
Small slit like capillaries Cavernous Hemangioma
Bigger and more dilated capillaries
Note: Dilated Lymph vessels and absence of RBC’s
Lymphadenopathies common on the cervical area, cannot diagnose without Reed sternberg cells. (binucleated, prominent macro nucleoli and shares common cytoplasm (acidophilic and eosinophilic)
RS cell is malignant.
Malignant cells are the lymphocytes.
Tumors of Epithelial Origin Stratified Squamous
Epithelium Basal cells of the skin Glandular Ductal Epithelial
lining Respiratory Epithelium Neuroectoderm Renal Epithelium Liver cell Urinary tract epithelium Placental Epithelium Testicular Epithelium
Fingerlike projection of the squamous epithelium
Ulcerated/Necrotic/Hemorrhagic
+ keratin pearls.
AKA: Rodents Ulcer
Basaloid Cells / Peripheral Palicading??? / Retraction artifact
Route of metastasis: Lymphatic
Nuclei are polarized and located basally/ no invasion/ necrosis / hemorrhage
Only difference is the presence of mucinous material in the cytoplasm
Route of metastasis: lymphaticHistogenic Origin: Epithelial
Glandular proliferation / Presence of inflammatory cell infiltrates.
Well differentiated – almost 100% glandular pattern.
Their should be fibrovascular core for diagnostic of “papillary” type of cancinoma.
+papillations.
+ Orphan Ani Nuclei.
+ Psammoma bodies
Hemorrhage/ necoris/ irregular distribution of papliations.
Cannot commit whether epithelial or mesenchymal - very prominent nucleoli and macro nucleoli / no particular pattern whether glandular, squamous or sarcomatous .
Trabecular – thickened composed of several layers of malignant hepatocytes.
Several layers of proliferating malignant transitional cells.
Presence of proliferation trophoblastic cells (syncytiotrophoblast and cytotrophoblast)
Extensive areas of hemorrhageShould not have the presence of villi
Germ Cell Tumor / Malignant Neoplasm of the testis.
Mixed tumor. Epithelial Components (duct architecture) and Mesenchymal Derivative (either cartilaginous of bony)
Triphasic tumor – 3 different cell types proliferation.
1. Stroma2. Ductal Epithelial Cell3. Blastema.
Teratogenous Tumor.
Benign – mature teratoma. Ex. Ovary
Malignant – immature
Presence of neuroectoderm signifies immaturity of the tumor
Histologic and Cytologic Features of Tumors
Benign Neoplasm Encapsulation Differentiation
Complete encapsulation – incomplete capsulation might be follicular carcinoma
Presence of capsule and proliferation of follicles, some does not contain colloid material.
Malignant Neoplasm Differentiation Features of Anaplasia Mitosis Tumor Giant Cells Tumor Necrosis Stromal Invasion and
Desmoplasia Metastasis
Keratin Pearl Dyskeratotic Cells / Individual
keratinization Intracellular Bridges – tight
junction connecting each keratonic cell
Features of Anaplasia Pleomorphism Hyperchromasia Increased N:C ratio Prominence of Nucleoli
Invasion at LOWER LEFT sidePresence of desmoplasia
Presence of malignant ductal cells in cords and tubular structures accompanied by a desmoplastic stroma.
Right side – remnants of normal lymph nodes, Left - metastatic cells.
Pre-invasive Lesions
Dysplasia Intact Basement Membrane
Ex: Cervical intraepithelial
neoplasia (CIN III), Cervix.
Intraductal Carcinoma-In-Situ, Breast
Left side – desplasticRight – normal
Full thickness dysplasia
Urinary Bladder Transitional cells Malignant
Lymph node
Metastasis
Lymphoid Tissue Metastasis Adenocarcinoma
Lipoma Adipocytes Histogenetic origin –
mesenchymal
Lipoma Adipocyes Mesenchymal Hematogenous
MalignantIntact Basement Membrane/Polarized NucleiSerous Adenoma
MalignantHyperchomicity/Increased NC ratio/Mitotic figures
LiverMalignant
Benign Pleomorphic Adenoma (mixed type)
Teratoma – 3 germ cell layers
Desmoplasia
Renal Cell Carcinoma
ThyroidPapillary Carcinoma of the ThyroidLyphatic Route
Metastatic Adeno Carcinoma
Cannon balling - classic sign, as a general rule metastasis are usually multiple against benign which is solitary
Metastatic Adenocarcinoma
BenignFollicular Adenoma of the Thyroid