PATHOLOGY OF TUMORS

1. PATHOLOGY OF TUMORSbyNorhan Ahmed El-Meniawy Faculty of medicine Egypt

2. TUMORS (NEOPLASIA) • Def: A neoplasm is an abnormal mass of tissue, the growth of which is virtually autonomous and exceeds that of normal tissue. In contrast to the non-neoplastic proliferations, the growth of tumors persists after cessation of the evoking stimuli. • The basic components of tumors: • All tumors have two basic components: • A-the transformed neoplastic cells: • The majority of tumors are monoclonal (arise from single transforms cell). • Few are polyclonal (neoplastic cells are descendants of many transformed cells). • B-the supporting stroma :composed of non transformed elements as connective tissues and blood vessels. Vascularization is effected by the release of tumor associated antigenic factorsdervied from the tumor cells or inflammatory cells that enter the tumor. NorhanAhmed El-Meniawy

3. The different classification of tumors: • Tumors are classified according to : • I- biological behavior into: • Benign tumor • Malignant tumor • Locally malignant tumors. • II-tissue of origin into: • Composed of one parenchymal cell type :tumors of epithelial origin& tumors of mesenchymal origin. • Composed of more than one neoplastic cell type (mixed tumors):usually derived from one germ layer. • Composed of more than one neoplastic cell type derived from more than one germ layer. Teratoma • III-gross appearance of the tumor (fungating ,annular, ulcerative ) • IV-aetiology of tumors(radiations,chemicalcarcinogens, etc • V-histology (differentiated, anaplastic etc). • IV-function(functioning tumors as insulinoma or nonfunctioning tumors).Norhan Ahmed El-Meniawy

4. There is another classification: • Dormant cancer: it is the appearance of metastasis many years after removal of the primary tumor. Seen in carcinoma of the breast and kidney and in uveal melanoma. • Latent cancer: the proliferation of cells which have the histological features of malignancy but remains clinically silent and do not meatstasis.best example is cancer prostate. • General features of benign tumors: • Benign tumors arise de novo. • The rate of growth is often slow and they rarely reach alarge size . • Mode of growth: • In solid structure :it is expansile.the central cell mass proliferate pushing the peripheral cells. Tumors expands compressing the surrounding structures . • Tumors growing from a surface project to the outside and form a papillary mass. Norhan Ahmed El-Meniawy

5. 2)encapsulation: benign tumors are often capsulated .the tumor is surrounded by a fibrous capsule consisting of compressed connective tissue. The capsule is derived from the host tissues and partly due to pressure atrophy of surrounding tissues. • ****some benign tumors are non capsulated as hemangioma,lymphangioma,naevi,leiomyoma and benign surface epithelial tumors. • d.Gross picture of benign tumors: • Tumors arising from solid organs: • Rounded or oval mass. • Mass is well defined. • Mass is capsulated. • Consistency is firm or soft. • Cut section is either solid ,cystic or papillary cystic. • Secondary degenerative changed in the form of hyaline and myxomatous degenerations may be seen. • Necrosis and hemorrhage are very rare or absent. • Norhan Ahmed El-Meniawy

6. Tumors arising from surface epithelium: • Tumor forms a polypoid mass : • Sessile(broad base) or pedunculated(narrow base). • Simple(smooth surface) or compound(branched surface). • e.Microscopicpicture: • 1.cellular differentiation: it is the extent to which tumor cells resemble comparable normal cells. Cells within benign tumors closely mimic corresponding normal cells. Cells are usually small and of equal size and similar shape. The nuclei are usually small compared to the cytoplasmic mass .mitotic figures are few or absent. • Norhan Ahmed El-Meniawy

7. 2-structural(histological) differentiation: benign tumor cells exhibit histological pattern similar to normal tissue. A benign tumor consists of acini similar to those normal thyroid. • 3.Benign tumors have well formed strong and few blood vessels. • G. Behavior: • Benign tumors are localized at the site of origin .they do not spread. • They do not recur after complete excision. • It may kill the host when compressing a vital organ like the brain. • It may cause obstruction when arise in a hollow organ like intestine. • It may produce hormones as in tumors of endocrine glands. • It may produce hormones as in tumors of endocrine glands. • Malignant transformation may occur and it is evident by: • Increased rate of growth. Norhan Ahmed El-Meniawy • Loss of cellular differentiation. • Inability to form intercellular ground substance. • Invasion of the capsule and surrounding tissues

8. General features of malignant tumors: malignant tumors arise DE novo or on top of precancerous lesion. They have a rapid rate of growth .they reach large size in short time. Mode of growth: mainly by invasion (infiltration).some degree of expansion also exists. Mechanism of invasion: invasion of the extracellular matrix by malignant tumor cells can by resolved into four steps: Detachment of tumor cells from each other Attachment to matrix components. Degradation of extracellular matrix. • Norhan Ahmed El-Meniawy

9. Detachment of tumor cells from each other: • Tumor cells remain attached to each others by several adhesion molecules including a family of glycoproteins called cadherins. • In several carcinoma ,there is down-regulation of epithelial (E) cadherins presumably reducing the cohesiveness of tumor cells. • Attachment to matrix components: • Tumors cells bind to laminin (a basement membrane of extraceller matrix)and fibrenoctin (an interstitial tissue component of extraceller matrix) via cell surface receptors. • Degradation of extracellular matrix: • Tumor cells secrete protolytic enzymes that degrade the extra cellular matrix. • These enzymes include type IV collagenase (cleave basement membrane collagen), cathepsin D ( a cysteine proteinase) and a urokinase –type plasminogen activator • Degradation of extraceller matrix creates passageways for tumor cell migration. • Norhan Ahmed El-Meniawy • Migration of tumor cells:

10. Factors that favor tumor cell migration in the created passageways include auyocrine motility factors cleave products of extraceller of extraceller matrix and repulsion of tumor cells by negative charges on the surface . • d. Gross picture of malignant tumors: • :Tumor arising from solid organs • Tumor forms a large ill defined mass. • False capsule from the compressed surrounding tissue may be seen. • It is infiltrating the surrounding tissues. • Firm consistency . • Sharp borders. • Cut section shows hemorrhage and necrosis. • Tumors arising from surface epithelium • Fungating :cauliflower like mass, surface is irreglar,friable in consistency, cut section shows hemorrhage and necrosis. Norhan Ahmed El-Meniawy

11. ulcerative: Large sized ulcer, edges are raised and everted,floor shows hemorrhage and necrosis ,base is fixed and indurated. Infiltrating :tumor infiltrates the underling tissue, in tubular organs as intestine ,it is either localized to a segment (annular) or may be diffuse. • Microscopic picture of malignant tumors: • 1.cellular anaplasia: it means changes in the cellular morphology and loss of polarity. • ***changes in cellular morphology: • Malignant cells are large in size. • They are available in size. • Nuclei are large with variable size and positions within the cells. • Nuclei are hyper chromatic due to duplication of DNA .the nucleocytoplasmic ratio is increased (1:1 instead of 1:4 or 1:6) • Nucleoli are large and prominent and have variable positions with nuclei.Norhan Ahmed El-Meniawy

12. Abundant mitosis and sometimes abnormal mitotic figures (e.g. . Tripolar spindles). The reflects the proliferative activity. • Tumor giant cells may be seen either contain large polypoid nucleus or multiple nuclei. • *** giant cells may occur in malignant tumors under a Varity of circumstances: • Giant cells that are seen in some tumors as a regular occurrence due to the nature of the growth e.g.osteoclastoma,osteosarcoma and Hodgkin's disease and chriocarcinoma. • They may result from chrosomal aberrations e.g.gaint cell variations of many neoplasms e.g. carcinoma of the lung and thyroid. • Norhan Ahmed El-Meniawy

13. They may form in a tumor that is growing under adverse conditions e.g. a tongue of lung cancer growing into the lumen of a bronchus. • Foreign body giant cells formed in relations to necrotic tissue cjolestrol,keratin . • ***loss of polarity : • Malignant tumors show loss of the normal relation between each cell and the neighboring ones and the surrounding tissues for example malignant acini are variable in size and shape ,their walls may be formed of single or multiple layers and the lumen may be eccentric and irregular .sometimes acinar formation fails and solid groups of tumor cells result. • 2.Structural (histological) differenation: • Malignant tumors fails to reproduce the exact appearance and pattern tissue.according to the degree of resembles of the structural pattern pf the tumor to that of the normal tissue NorhanAhmed El-Meniawy

14. carcinoma may be graded as: • Well differentiated (grade I): greatly similar ti the pattern tissue. • Moderatlydifferentied (grade II):moderately similar to pattern tissue. • Poorly differentird (gradeIII): poorly similar to pattern tissue. • Undifferentied (grade IV,anaplastic carcinoma): not similar to parent tissue .better differentied tumors tend to show lesser degrees of celluleranaplsia. • 3.Other features: • The stroma is highly vascular. • Vessels may be thin walled as in sarcomas. • Secondly changes as myxoiddegeneration may occur. • Areas of hemorrhage and necrosis are common . Norhan Ahmed El-Meniawy

15. F. Behavior and prognosis of malignant tumors: • Malignant tumors do not remain locally at site of origin. They undergo local and distant spread . • Recurrence after surgical removal is common and may be due to : • Tumor cells left over at the operation site .these cells may remain dormant and recurrence appears after years. • A new start near by the first tumor from a field of high neoplastic potentiality . • Malignant tumors lead to death of the patient due to: • Anemia: caused by : • -ulceration and bleeding of the tumor. • -Bone marrow destruction by metastasis. • -folic acid deficiency as it is utilized by tumor cells. Norhan Ahmed El-Meniawy

16. Autoimmune hemolytic anemia. • Malnutrition : tumors of the gastrointestinal tract intefence with ingestion .digestion and absorption of food. • Renal faiule:due to obstruction of the urinary tract caused by tumors of the genitourinary system or rectum. • Obstructive jaundice and liver failure: caused by tumors of the liver ,urinary tract and pancreas. • Increased intracranial tension and pressure on vital centers: caused by intracranial tumors. • Chronic toxemia: caused by secondary bacterial infection in ulcerated tumors . • Cachexia : it is marked wasting manifested by marked weight loss accompanied by anorexia and anemia . Norhan Ahmed El-Meniawy

17. It result from: • Anemia and toxemia . • Functional failure of different organs. • Tumors necrosis factor-α(TNF-α).it is released from activated macrophages and causes suppression of appetite and interferon with fat metabolism. • Mechanism and method of spread of malignant tumors: • Local spread • Distant spread: • Lymphatic spread • Hematogenous spread • Transcoelemic spread • Transluminal spread NorhanAhmed El-Meniawy • Implantation

18. A.Local spread: • Malignant cells spread directly by invasion along lines of least resistance. • Preiosteium,bone,cartilage and fibrous tissues delay direct spread. • Direct spread to skin or mucous membranes results in malignant ulcer. • Safety margin: in malignant tumors, the microscopic extent of the tumor exceeds its macroscopic boundaries so surgical excision must incorporate a wide extent to the surrounding tissues :guided by frozen sections, till reaching a margin that is free of neoplastic cells. • Perineural spread : a particular form of spread occurring along the perinural space as in prostatic carcinoma . It causes nerve compression with severe pain. Norhan Ahmed El-Meniawy

19. lymphatic spread: it is more commonly seen with carcinoma than with sarcoma. Nodal involvement is influced by the interaction of tumor cells with organ specific receptors, for example, certain tumor cells have high levels of CD44;an adhesion molecule that binds endothelial venules in lymph nodes, there by facilating nodal metastasis . Lymphatic spread occurs by two ways; lymphatic embolism and lymphatic permeation. Lymphatic embolism Tumor cells invade the wall of the lymph vessels, detached tumor cells are carried as emboli and reach the lymph node via afferent lymphatic's. Tumor emboli are arrested in the subscapular sinus of lymph nodes. Malignant cells proliferate and gradually destroy the substance of the node invade the capsule. • Norhan Ahmed El-Meniawy

20. Spread from one node to another of the same group may occur via efferent lymphatic or by direct infiltration of the capsule. Distant groups are affected later and finally the thoracic duct is involved and the malignant cells enter the general circulation. Gross picture : Early:the lymph nodes are enlarged,firm,dicrete,mobie,cut section is greyish white with foci of necrosis. Microscopically: The matastatic tumor resembles the primary tumor from which it is derived. Lymphatic permeation: Tumor grows within the lumen of the lymph vessels as a solid cord causing lymphatic obstruction and marked lymph edema. • Norhan Ahmed El-Meniawy

21. 2.Obstruction of the lymph vessels may lead to retrograde lymph flow and retrograde lymphatic spread. • 3.Lymphatic permeation occurs specially in breast, prostatic and bronchogenic carcinomas. • Hematogenous spread • Invasion of extraceller matrix by metastatic sub clone of tumor cells • Vascular dissemination and homing of tumor cells: • By a similar mechanism tumor cells cross the vascular basement membrane and become intravasated. • Tumor cells from emboli by adhering to leukocytes and platlets.aggregation tumor cells are afforded some protection from the antitumor host effector cells. • Tumor emboli adhere to the vascular endothelium, cross basement membrane, become extravasated and settle in a new site and release tumor-associated angoigenic factors and a metastatic growth develops.Norhan Ahmed El-Meniawy

22. Malignant tumor cells may reach blood stream from thoracic duct. • The site where tumor cells emboli lodge and produce secondary growth is influenced by: • Anatomical site of the primary tumor. • The microenvironment of the organ or site. Tissue rich in prostate inhibitors might be resistant to penetration by tumor cells. • Course of tumor emboli: • Emboli derived from primary tumor of organs drained by systemic veins as • breast,skin,bone and kidney are carried by pulmonary arteries to the lungs • Emboli from primary or secondary lung tumors are carried by pulmonary veins to left side of the heart then to systemic circulation causing metastasis in different organs as brain,boneand liver.NorhanAhmed El-Meniawy

23. 3.Emboli from tumors of organs drained by portal blood as the gastrointestinal tract and gall bladder are carried to liver nay occur via hepatic veins to inferior vena cava to right side of the heart to lungs. Emboli from tumor ofpelvic,abdominal or thoracic organs may give metastasis to brain, spinal cord and vertebrae without affecting the lungs via the vertebral system of veins which have wide anastomotic channels connecting them with lumbosacral, abdominal and thoracic veins. Organs of metastasis : The liver,lung,bone and brain are common sites for metastases. Metastasis are rare in muscles,spleen,pancease and intestine. Grossly: metastasis appear as multiple well defined non capsulated nodules with grayish white cut section. • Norhan Ahmed El-Meniawy

24. Microscopically: as primary tumor. • Effects of tumor metastases: • Anemia • Leucopenia • Thrombocytopenia • Metastic calcification • Pathological fracture except cancer prostate(osteosclerotic) • Transcolemic spread: • Occurs in tumors of organs covered with serous membranes. • When serosa covering is infiltrated by malignant cells, tumor cells separate and fail in the related sac . • Cells are implanted on the surface of another organ,prolifertae and produce metastases.NorhanAhmed El-Meniawy

25. 4.This may be accompanied by hemorrhagic effusion caused by malignant occlusion of lymphatics and veins and mechanical irritation by the tumor cells. Trans pleural and trans pericardial spread from carcinoma of the lung or breast causesmatastases on the diaphragm, paravertebral grooves and cost phrenic recess accompanied by hemorrhagic pleural or pericardial effusion. Transperitonial spread from gastric carcinoma causes metastic omental nodules and hemorrhagic ascites. Malignant brain tumors may give rise to tumor cells within the CSF with metastses on the lining of the venticles, base of the brain and spinal cord. • Norhan Ahmed El-Meniawy

26. Krunkenberg tumor: it is bilateral ovarian metastases associated with gastric carcinoma.formel they were thought to be the result of transcolemic spread but now believed to be due to retrograde lymphatic or blood spread .they can also occur in carcinoma of colon,breast,urinary bladder and biliary tract. Transluminal spread: malignant cells detached from trasititional cell carcinoma of the renal pelvis may become implanted in the mucosa of the urinary bladder forming secondary deposits. Implantation: 1.Surgical implantation: instruments contaminated with malignant cells during surgical management of a tumor may transfer tumor cells into the surgical wound causing secondary deposits. 2.Secondry tumor in the upper lip from carcinoma of the lower lip 3.Implantion through trans luminal spread. • Norhan Ahmed El-Meniawy

27. Tumor angiogenesis • Tumor cells ,similar to normal cells, need oxygen ti survive. • Vascularization of tumors by host-dervied blood vessels has a profound influence on tumor growth. • Vasclization is effected by the relase of tumor associated angiogenic factors dervied from tumor cells or im=nflammatory cells as macrophages that enter the tumor .the mist important angiogenic factors are vascular endothelial growth factor(VEGF) and basic fibroblast growth factor (Bfgf).also EGF and PDGF. • Antiangiogenic factors are also produced by tumor cells or host cels.these include angiostatin,endostatin,vasculostatin. • Tumor growth is contrlled by the balance between angiogenic and antiangigenic factors. • Norhan Ahmed El-Meniawy

28. Molecular genetics of metastses: • The sequential steps involved in invasion and metastases may be interrupted at any stage by postal factors . • Cells within a primary tumor are heterogenic with respect to the metastatic abilities. Only certain sub clones can complete all the steps and form secondary tumors at distant sites. • Cells of these sub clones are capable of expressing surface adhesion receptors and can produce collagenases and mobility factors. • No single metastses gene has been identified with the exception of enzymes which is essential for metastses in rhabdomysarcoma and osteosarcoma. • Mutation in the gene for a certain (protein under the plasma membrane to which E-cadherin is linkrd)reduce expression of E-cadherin and facilitates metastses. • Transfection with the gene for tissue inhibitors of metalloproteinase reduces metastasis.Norhan Ahmed El-Meniawy • There are several genes that had been proposed as suppressors of metastasis.theyiclude NM23,KAI-1 AND KISS genes.

29. The kinetics of tumor cell growth and their clinical implications • Kinetics of tumor cell growth: tumor cell growth is influenced by: • Doubling time of the tumor cells: the total cell cycle time of many tumors is equal to or longer than that of corresponding normal cells. • Growth fraction(GF):it is the proportion of cells within the tumor cell population that are in the replicative pool(out of the G0) .most cells within a clinically detectable tumors are not within the replicative pool by being shed, by differentied or reversion to G0.the GF does not usually exceeds 20%.Norhan Ahmed El-Meniawy • Cell production and loss: progressive growth of tumors is explained by an imbalance between cell production and cell loss.in tumors with high GF this imbalance is large resulting in more rapid growth.

30. Clinical implications: The rate of tumor cell growth depend upon the Gf and the degree of imbalance between tumor cell production and cell lise.high GF,as in certain lymphomas is associated with rapid growth. Cancer chemotherapy :most antineoplastic agents act on dividing cells thus tumors with high GF are the most susceptible to anticancer agents. Latent period of tumors: because most tumor cell leave the replicative pool the several months ti years before a tumor becomes clinically detectable. The benign epithelial tumor: papilloma & adenoma. The pathological features and complications of papilloma: Def.: papilloma is a benign tumor of surface epithelium .it is commonly single but may be multiple. • Norhan Ahmed El-Meniawy

31. Types: • Sequamous cell papiloma • Def:benign tumor of stratified squamous epithelium • Sites:skin,lips,oral mucous,pharynx,larynx,cervix,vagina,anal canal. • Gross picture: • :small sessile or pedunculated projection • With growth progression a complete papillary pattern is produced. • Microscopic picture: • Connective tissue cores covered by thick stratified squamous epithelium showing : • Basal hyperplasia • Acanthosis • Hyperkeratosis NorhanAhmed El-Meniawy • Complication: rarely change to squamous cell carcinoma

32. Transitional cell papiloma(villous papilloma) • Def.: benign urothelial tumor • Sites: urinary bladder, ureter, renal pelvis • Gross picture: • Tumor appear as a velvety mass of delicate papillary processes • Microscopic picture: • Delicate vascularized connective tissue cores covered by not more than six layers of regular transitional cells • Complications:hematoma&change to transitional cell carcinoma • Norhan Ahmed El-Meniawy

33. Duct papiloma • Def.: benign tumor occurring in the major ducts of mammary gland • Sites: major duct of mammary gland • Gross picture: • small complex papillary projection inside the duct lumen. • Microscopic picture • Delicate vascular cores covered by regular ductal epithelial cells. • Complications: bleeding per nipple change to duct carcinoma • Adenomatous polyp • Def:benign tumor of gastrointestinal tract mucosa • Sites:mucous of the gastrointestinal tract & gall bladder • Gross picture: • Sessile pedunculated or complex papillary projection. • Microscopic picture: • Proliferated mucosal glands lined by columnar epithelium and a supporting fibro vascular stroma. • Complications:gastreointestinal bleeding &change to adenocarcinoma NorhanAhmed El-Meniawy

34. Adenoma • Def.: adenoma is a benign tumor of endocrine and exocrine glands arising due to glandular proliferation. • Sites: endocrine glands,liver,breast,salivary glands, renal tubules,ovary,mucous glands of stomach and intestine. • Gross picture: • Mass • Well defined • Capsulated • globular or ovoid\cut section may be solid,cystic or papillary cystic • Norhan Ahmed El-Meniawy

35. Microscopic picture: • Simple adenoma (tubular adenoma):proliferated glands lined by cuboidal or columnar delicate fibro vascular stroma. • Fibroadenoma:proliferated fibrous tissue between epithelial elements • Cystadenma:retained secretions in some adenomas leads to cystic spaces lined with cuboidal or columnar • Papillary cystadenoma:the epithelial lining in cyst adenoma continue to proliferate forming papillae. • Simple adenoma: as pancreatic adenoma. • Fibroadenoma:as breast fibro adenoma which consists of ducts lined by inner cuboidal and outer flattened cells and separated by proliferating fibrous tissue. • Cyst adenoma and papillary cyst adenoma :as ovarian cyst adenoma and papillary cyst adenoma.NorhanAhmed El-Meniawy

36. Complications: adenoma of endocrine glands may be hormone secreting thyroid adenoma may lead to thyrotoxicosis. • Malignant transformation to adenocarcinoma • Benign mesenchymal tumors: • Connective tissue tumors: as • fibroadenoma,lipoma,chondroma,osteochondroma,osteoma&myxoma • Tumors of muscles as leiomyoma&rhabdomyoma • Tumor of vessels as haemangioma &lymphangioma • Brain coverings as meningioma • Pathological features of fibroma • Def:fibroma is un common benign tumor of fibrous tissue. • Sites:subcutanous/ sub mucous/periostum/periarticular ligaments/intermuscular septa/fibrous stroma of organs as breast, ovary and kidney. • Norhan Ahmed El-Meniawy

37. Gross picture: • Mass globular, ovoid or pedunculated. • Well defined • Capsulated • Consistency is either soft(cellular fibroma)or hard (hard fibroma). • Cut section shows interlacing or whole bundles .bundles are greyish pink in cellular fibroma and greyish white in hard fibroma. • Microscopic picture: • Tumor consists of variable proportions of fibroblasts (spindle shaped cells with spindle nuclei with tapering ends),collagen and blood vessels. • Fibroblasts are predominant in cellular fibroma while in hard fibroma collagen is predomint. • Norhan Ahmed El-Meniawy

38. Complications: • Hyaline degeneration • Myxomatous degeneration • Cyst formation • Calcification and ossification • Malignant transformation into fibro sarcoma is rare. • Fibromatosis • Def: a group of lesion characterized by non-neoplastic reactive proliferation of fibrous tissue resulting in formation of irregular non capsultd tumor like masses. These lesions are adherent to the surrounding structures(benign infilitrationor pseudosarcomatous proliferation),recurrence after excision is common. Norhan Ahmed El-Meniawy

39. *****desmoid:recurrent aggressive fibromatosis of two types: • Abdominal desmoid:infiltration masses arising from the musculo-aponeurtic structures of the anterior abdominal wall in parous woman. • Extra-abdominal and intra- abdominal desmoids affecting men and woman equally. • **palmer fibromatosis : affecting the palm(dupuytren contracture) • Planter fibromatosis : affecting the foot. • Penile fibromatosis: affecting the penis(peyonie disease) • Lipoma • Def:lipoma is a common benign tumor of fatty tissue. • Sites:mediastenum,omentum,subcutanousfat tissue of the neck ,shoulder,back and buttocks,inramusculaesepta,fat of internal organs as kidney&retroperitonial.NorhanAhmed El-Meniawy

40. Gross picture: • Mass • Well defined • Capsulated • Round or lobulated • Soft consistency • Cut section is bulging, pale yellow and greasy. • Microscopic picture: fibrous septa divide the tumor into lobules consisting of mature fat cells with vacuolted cytoplasm and eccentric flattened nuclei with electron microscopy small oval cells with small cytoplasm vacuoles are seen (precursors of mature fat cells) • Variants: • Fibrolipoma(abdument fibrous tissue) • Angiolipoma(numerous vessels) • Myxolipoma(myxoid change) Norhan Ahmed El-Meniawy

41. Chondroma • Def:chondrolipoma is a benign tumor of cartilage. • Sites: • Short bones of hands and feet. Within the interior of bone(enchondrium). • It is usually solitary but may be multiple(ollier<s disease) • 2) Subperosteal or juxtacorticalchondroma. • 3)Flat bones as sternum ,ribs, scapula and pelvis. • 4)Ends of long bones. • 5)Rarely the larynx and bronchi • 6)Soft tissue chondroma.NorhanAhmed El-Meniawy

42. Gross picture: • Mass • Well defined • Lobulated • Capsulated • Cut section is bluish and translucent. • Consistency is firm • Borders are sharp. • Microscopic picture: • Fibrous septa divide the tumor into lobules of consisting of hyaline matrix and cartilage • cells inside lacunae. • Cartilage cells (chondrocytes)are rounded with vacoulted cytoplasm. They are arranged singly or in groups. Norhan Ahmed El-Meniawy

43. Complications: • Myxomatousdegeneration • Calcification • Ossification • Malignant transformation into chondrosarcoma .it is more common in multiple enchondromasarcomas than with solitary chondroma. • Osteochondroma • Def: • osteochondroma(exostosis) is developmental tumor – like abnormality • It results from aberrant lateral growth of the epiphyseal cartilage.Norhan Ahmed El-Meniawy

44. They arise in long bones specially the fumer. • Their growth is arrested after puberty(with closure of epiphysis). • The lesion may be single or multiple (the multiple varient, called multiple exostosis,is a hereditary autosomal domunt disease). • Gross picture: • Mushroom-shaped lateral projection composed of oa bony stalk and head covered by a cartilaginous cap. • Microscopic picture:cancellous bone covered by cartilage. • Complications: • Pressure effects . • Malignant transformation into chondrosarcoma (more than with mulitpleexostosis). Norhan Ahmed El-Meniawy

45. Osteoma • Def:osteoma is a benign tumor arising from bone. • Types: osteoid osteoma & compact ostoma(ivory) • Ostoidosteoma • Origin and sites: in any bone common in the cortex and less commonly within the medullary cavity. The femur and tibia are the commonest affected. • Gross picture: • Solitary • Less than 1 cm in diameter. • Pink, gritty and friable. • Subperiosteal lesions excite a tremendous amount of reactive bone that encircles the tumor which appears radiologic ally as a translucent small lesion (nidus)with dense sclerotic margins. Norhan Ahmed El-Meniawy

46. Microscopic picture: • Trabecular of osteoid and poorly mineralized oven bone rimmed by osteoblasts • Loose richly vascularized intervening stroma • Complications: pain due to production of prostaglandin E2. • Compact(ivory)osteoma • Origin and site: membranous bones of the skull. • Gross picture: hemispherical non capsulated hard ivory –like mass. • Microscopic picture: concentrically arranged bone lamellae. • Complications:tumor arising from the outer table cause disfigurement. • Tumors arising from inner table cause pressure effect(proptosis)NorhanAhmed El-Meniawy

47. Myxoma • Def: a rare benign tumor composed of myxomatous tissue.it arise from the remnants of primitive mesenchyme. • Sites: heart(atrial septa) • Jaw(in relation to teeth) • Gross picture: • Soft gelatinous mass. • The capsule may be incomplete or absent. • Microscopic picture: stellate shaped myxoma cells embedded in mucoid matrix. • Complications: necrosis • Hemorrhage • Cyst formation • Cardiac myxoma may be pedunculated and block the atriovenous valves.NorhanAhmed El-Meniawy

48. Leiomyoma • Def : a common benign tumor of smooth muscles. • Sites: wall of esophagus,stomach,intestine,urinary bladder and skin& uterus • Gross picture: • Single or multiple . • Well defined • No capsulated but may be surrounded by a false capsule from compressed surrounding muscles. • Firm in consistency. • Cut section is greyish brown and wholly • Uterine leiomyoma may lie with the myometrium(intraluminal or interstitial)or beneath the serosa (subserous) or beneath the endometrium(submucous)NorhanAhmed El-Meniawy

49. Microscopic picture: Interlacing bundles of smooth muscle cells (fusion cells with abundant eosinophiliccytoplasm and fusiform nuclei with blunt ends). Fibrous stroma containing blood vessels. *the fibrous stroma may be abundant in uterine myomaparticularly after the menopause and the tumor is called fibromyoma or fibroid. Complications:hayline degeneration Myxomatousddegeneration Cyst formation Calcification Malignant transformation into leiomyosarcoma is extrmely rare. Uterine myoma may lead to irregular uterine bleeding and infertility • Norhan Ahmed El-Meniawy

50. Rhabdomyoma • Def: rare benign tumor of striated muscle. • Site: the myocardium is the commonest site • Grossly: reddish grey soft mass that may or may not be capsulated. • Microscopically: branched spindle shaped cells with transverse stations separated by fibrous steoma. • Complications: change to rhabdomyosarcoma.Norhan Ahmed El-Meniawy