MMB (035) Bone and Soft tissue tumours I Flashcards
What is metaplasia ?
an adaptive, reversible change in which one adult “mature, differentiated” cell type is replaced by another of the same category (epithelial or mesenchymal).
What is dysplasia ?
A non-neoplastic, disordered epithelial cell proliferation ;
• Low-grade changes may be reversible
• High-grade dysplasia is premalignant
Cause of Dysplasia ?
Chronic irritation ;
Examples:
-Chronic cervicitis → cervical dysplasia
-Bilharzial Cystitis → urothelial dysplasia
Microscopic features of Dysplasia ?
Atypia + loss of normal orientation “polarity”
Features of atypia ?
- Pleomorphism
- Hyperchromatism
- Increased N/C
- Increased mitosis
Comment on this epidermal slide
Abnormal epidermis with irregular scattering of keratinocytes showingloss of polarity
Grades of Dysplasia ?
Atypia& loss of polarity ;
-Mild: epidermal lower 1/3
-Moderate: 2/3 of epidermis
-Severe: whole epidermal thickness
Neoplasia ?
-an acquired abnormality in which there is abnormal, uncoordinated and excessive cell growth
-persists after the initiating stimulus has been removed (autonomous)
-involves genetic alterations in the neoplastic cells
Detailed definition of Neoplasm ?
A neoplasm is a persistent, abnormal mass of tissue, the growth of which exceeds & is uncoordinated with that of the normal tissue and persists in the same manner after cessation of the stimulus that evoked it.
: The suffix …..oma = neoplasm
Main 2 components of neoplasms ?
- Transformed, neoplastic cells
- Supporting stroma: connective tissue & blood vessels.
Tumor vascularization is affected by (cells) :
- Tumor cells
- Inflammatory cells
Both
» (secrete) tumor- associated angiogenic factors
Compare between malignant and benign tumors accoriding to :
-invasion
-localization
- growth rate
- resemblance to parent tissue
Mode of growth for solid tissue benign tumors ?
Mode of growth for solid tissue surface tumors ?
Non-encapsulated benign tumors include:
-leiomyomas
- hemangiomas
-lymphangiomas
-nevi
-benign surface epithelial tumors
Cell morphology of Benign tumors ?
a. Tumor cells mimic cells of original tissue.
b. Cells are small, uniform in size and shape.
c. N/C is preserved.
d. Mitotic figures are minimal and normal.
Benign Tumor architecture ?
a. Same histological pattern as tissue of origin
b. Well- developed vascular stroma
A major Effect of benign tumors on neighbouring tissue ?
compress neighboring tissue»_space; atrophy
Comment on the possibility of benign tumors recurrence
No recurrence if totally excised
Ways by which a mass neoplasm can be described ?
-Hard
-Fixed
-Irregular
-Ill-defined
Ways by which a surface neoplasm can be described ?
- Polypoid
- Ulcerative mass
- Infiltrative
Anaplasia ?
lack of differentiation
Steps by which a tumor starts invasion ?
1.Detachment of Tumor cells
2.Attachment of cells to matrix components
- Degradation of extracellular matrix
- Migration of tumor cells by chemotactic factors
Mechanisms of distant spread of malignant tumors ?
• Lymphatic
• Hematogenous
• Transcoelomic
• Transluminal
• Implantation
A method of local tumor spread with direct affection on nerves ?
Perineural spread: Spread along perineural space compression»_space; severe pain.
Define Metastasis
development of secondary malignant implants not continuous with the primary tumor.
Do all malignant tumors metastasize ?
Though all malignant tumors undergo local spread, some do not give distant metastasis»_space; LOCALLY MALIGNANT TUMOURS
Lymphatic spread is more common in (carcinoma/sarcoma)
carcinoma
Two ways of lymphatic spread:
- Lymphatic embolism
- Lymphatic permeation
Explain Lymphatic embolism metastasis
Explain Lymphatic permeation metastasis
• Tumor grows as solid cords within lymph vessels causing obstruction of lymph flow»_space; localized edema.
Lymph Node Metastasis Gross ?
Lymph Node Metastasis
• Gross: lymph nodes are:
- enlarged
- firm
Microscopic appearance of matastatic cells ?
Metastatic tumor resembles the primary Tumor ;
(red arrows point to gross and microscopic picture of a lymphoid tissue// yellow arrows point to metastatic infiltration)
Two ways of Hematogenous metastasis ?
1) Direct ; through invasion of basement membrane»_space; enters blood vessels
2) Indirect ; lymphatic spread»_space; Thoracic duct »_space; pulomanry artery
Primary organs that send veinous metastatic emboly ?
- Tumors of organs drained by systemic veins ;
Bone and kidneys
Primary sites where veinous metastatic emboly rest ?
Through which veins can metastatic emboli reach the vertebral system ?
Through :
-Thoracic veins
-Abdominal veins
-Lumbosacral veins
Metastatic tumors(e.g. from lungs, thyroid & breast)usually cause osteolytic/blastic lesions
osteolytic ; osteoclastic bone resorption
prostatic adenocarcinoma metastasis to bone usually cause osteolytic/blastic lesions
osteoblastic bone formation
Bone metastasis in vertebrae, ribs, sternum, pelvis, skull, and ends of long bones ; develops in white/red marrow , causing ….(anemia)
red marrow ; causing pancytopenia
How does an organ invaded with metastatic deposits look like?
• Gross: multiple, well-defined, non-encapsulated nodules
• Cut section: grayish- white nodules
• Microscopic: as the primary tumor.
Define Trans-coelomic spread and give an example
(spread through body cavities)
What do you see ?
And diagnose the abnormality
Dense, compact bone and broad trabeculae of mature bone ;
Osteoma (benign)
Age preferance of Osteoma ?
More frequent in middle- aged males.
Investigate the imaging , point to the lession and give possible diagnosis
Osteoma (benign)
give diagnosis and comment on the findings
Osteogenic sarcoma ;
• Bone destruction with penetration of cortex
• Lifting of the periosteum presents as Codman’s triangle
• Infiltration of adjacent soft tissues
• Spicules of bone arise from the periosteum around the tumor perpendicular to the shaft giving a “Sun- ray, sun-burst, hair on end” appearance
comment on the gross picture
Large grayish-white mass with wide areas of hemorrhage and necrosis.
> > Osteosarcoma
Figure shows gross sample of Osteosarcoma lesion ; can you see codman’s triangle ?
What’s Codman’s triangle ?
Periosteal reaction may appear as the characteristic Codman triangle ; Extension of tumor through the periosteum
comment on microscopy and diagnose
-Tumor cells are present in lacunae and arranged in lobules.
-Osteoid matrix is seen on the lower right of the image.
Diagnosis:
Chondroblastic osteosarcoma
comment on microscopy and diagnose
Figure shows abnormal growth lesion ; diagnose
Benign: Chondroma (Enchondroma) ;
• A benign tumor composed of mature hyaline cartilage
• It can be either solitary or multiple
Comment on gross picture and define what it is
• Well defined, capsulated mass
• Lobulated in shape
• Cut section: bluish and translucent
• Firm in consistency with sharp borders
—Diagnosis : Chondroma
investigate the microscopy and mention what the symbols stand for
-fibrous septa (F) divide the tumor into ;
-lobules (L) of cartilage (hyaline matrix and cartilage cells inside lacunae).
-Cartilage cells (chondrocytes) are rounded with vacuolated cytoplasm. They are arranged singly or in groups
—Diagnosis : Chondroma
investigate the microscopy and mention what the symbols stand for
-fibrous septa (F) divide the tumor into ;
-lobules (L) of cartilage (hyaline matrix and cartilage cells inside lacunae).
-Cartilage cells (chondrocytes) are rounded with vacuolated cytoplasm. They are arranged singly or in groups
—Diagnosis : Chondroma
Comment on x-ray and give a possible diagnosis
Chondroma ;
Localized, radiolucent defect Lobulated with bony expansion
Gross picture illustrates chondrosarcoma samples , Comment , and on the expected consistency
Gross: Firm, grayish- white mass, variable in size.
-Cut section resembles that of cartilage with foci of calcification, cysts and necrotic areas.
What do you see ? And give possible diagnosis
Radiographs of pelvis show a large exophytic growth (G) arising from right iliac bone with chondroid matrix (rings and arcs of calcification).
Radiographic chondroid matrix ?
rings and arcs of calcification
CASE STUDY: An autopsy specimen of a 52 year old man who was complaining of progressive pain and swelling at the left pelvic region for many years.
What do you see ?
CASE STUDY: An autopsy specimen of a 52 year old man who was complaining of progressive pain and swelling at the right pelvic region for many years.
What do you see ?
comment on gross picture and diagnose
comment on radiography and diagnose
Well-defined lytic lesion that involves the metaphysis and epiphysis is typical of a giant cell tumor
typical x-ray presentation of giant cell tumor ?
Well-defined lytic lesion that involves the metaphysis and epiphysis is typical of a giant cell tumor
comment on radiography and diagnose
• Lytic lesion with characteristic soap- bubble appearance
-Well-defined lytic lesion , that involves the metaphysis and epiphysis is typical of a giant cell tumor
Comment on Gross Picture and give possible diagnosis
The tumor mass is greyish-white, showing destruction of the medullary cavity by hemorrhage and necrosis, extending into the cortex and adjacent soft tissues
-Ewing’s sarcoma
(Primitive or peripheral neuro-ectodermal tumor (PNET))
Figure illustrates microscopy of a bone tumor , comment and diagnose
-The tumor is composed of sheets or cords of undifferentiated small round cells larger than lymphocytes.
-Cells have a scanty cytoplasm rich in glycogen.
Diagnosis : Ewing’s Sarcoma ;
(Peripheral neuroectodermal tumour) [PNET]
A bone tumor commonly mistaken for osteomyelitis ?
And why ?
Ewing’s sarcoma
Primitive or peripheral neuro-ectodermal tumor (PNET) :
- due to it’s microscopy resembling large lymphocyte like cells , and increased ESR and leukocytes in CBC
Figure illustrates plain radiography of a bone tumor , diagnose the tumor and comment on it’s x-ray findings
diagnose the tumor using the gross picture
Rhabdomyosarcoma
Parent cell of Rhabdomyosarcoma ?
RHABDOMYOBLASTs
