Oral Pathology PDF

Wondershare PDFelement 8 Raghad Al-Jabari Lina Hasan Dana al-Toum Dr.Faleh |Page1 Wondershare PDFelement Salivary gland (SG) tumors - uncommon - Incidence around 1-6 cases per 100,000. - Mainly seen in females in middle age and elderly. - These tumors develop in : Major salivary glands...

Wondershare PDFelement 8 Raghad Al-Jabari Lina Hasan Dana al-Toum Dr.Faleh |Page1 Wondershare PDFelement Salivary gland (SG) tumors - uncommon - Incidence around 1-6 cases per 100,000. - Mainly seen in females in middle age and elderly. - These tumors develop in : Major salivary glands (80%): 90% of it in the parotid gland ~10% in the submandibular gland ~.3% in sublingual gland Minor salivary glands (20%): (55%) in the palate (The most common site) (20%) in the upper lip (The second most common site) It is Rare to have salivary gland tumor in the lower lip. (~25%) Other sites where minor SG can develop SG tumors, like buccal mucosa, floor of the mouth, soft palate …. - In term of malignancy: • Around 15% of parotid glands tumors are malignant. • 30% of Submandibular glands tumors are malignant. • The vast majority of sublingual gland tumors are malignant (85%). It is rare to have a tumor in the sublingual gland, but when you do there is 85% chance for it to be malignant. • In the minor salivary gland, 50% chance for malignancy. ~15% |Page2 Wondershare PDFelement Slow growing, soft or rubbery, x ulcer, x N ~ fast-growing, ± hard, ± ulcerate, ± invasion, ± N - Basic classification of salivary glands tumors: A) Benign tumors (adenomas) 1)Slow growing (over years). 2)Soft or rubbery swelling in the gland (on palpation). 3)Do Not cause ulceration to the mucosa in the oral cavity or in the skin. 4)Do Not cause neural manifestations (numbness, paresthesia, or paralysis to the nerve). The most common type is pleomorphic adenoma, also warthin tumor, basal cell adenoma, oncocytoma, canalicular adenoma and ductal papillomas can develop in the salivary glands. |Page3 Wondershare PDFelement B) Malignant tumors (Carcinomas) : 1) Fast growing. 2) Usually they are Hard clinically. 3) They cause ulceration to the overlying mucosa or skin. 4) Invasion to the surrounding tissues, may cause necrosis in the area. 5) The patient may develop neural manifestations like facial paralysis (paresthesia to facial nerve). Most common types: Muco-epidermoid Carcinoma and Adenoid cystic Carcinoma. Benign Tumors ➢ Pleomorphic adenoma (PA) - As the name implies “pleomorphic”, it is not a result of pleomorphism, but actually there is a mixture of tissues (epithelium and connective tissue components mixed together in the tumor), and it is highly difficult to find 2 identical tumors or even 2 identical areas in the tumor itself because of this mixture between epi. And CT components. - So, there is NO pleomorphism in the cells and also it is called mixed tumor. The origin of the tumor is epithelium and/or myoepithelium cells (it is NOT from mixed origin, but because of the mixture in the components between epi. And CT it is called mixed tumor). Again NOT MIXED ORIGIN. - It is the most common tumor, 40-60% of all salivary glands tumors, so it is important to know its details. |Page4 Wondershare PDFelement - 84% of PA cases develop in the parotid gland, which represents 70% of all the parotid gland tumors and 80% of which develop in the superficial lobe of the parotid (the vast majority). PA in Parotid gland (PG) - 8% of PA develop in the submandibular gland, and it represents 50% of submandibular gland tumors. PA in Submandibular gland (SMG) - 7% of PA cases originate in minor glands, representing about 45% of all the tumors of the minor salivary glands, mostly in the palate (55%) without any ulceration, destruction, or paresthesia in the region. ❖ Clinical features: 1) Slowly growing swelling 2) Well-defined, capsulated (benign) 3) Painless 4) Rubbery swelling on palpation |Page5 Wondershare PDFelement 5) Located at the angle of the mandible, anterior to the tragus, external to the ramus and may cause elevation to the lobe of the ear W-d, painless, rubbery swelling Angle of mandible Elevation of the lobe of the ear + multinodular 6) Usually, it consists of one smooth swelling but sometimes it is multinodular or lobulated (multiple swellings) and this is related particularly to the capsule, the capsule of the tumor is deficient in some areas which leads to growth outside the capsule giving another nodule. This lobulation is also a feature of recurrent PA. ❖ Histologically : 1- Extensive variations (there is epithelial and stromal (CT) components mixed together). 2- Fibrous capsule, there is a deficiency in some areas of the capsule so the tumor protrudes from this deficient area leading to another nodule formation “clinical significance, and it will cause multi nodularities”. The second significance of the deficiency, it is the cause of increased recurrence. Fibrous capsule |Page6 Wondershare PDFelement Because if the tumor was just inoculated, some of these nodules that are protruded outside the capsule may be left behind and cause recurrence, so usually PA is removed with a bit of safety margins around the tumor. 3- Epithelial component (epi and myoepi): a) Epithelial duct cells ( line duct-like structures ) Epithelial duct Cs line ductlike structures b) Myoepithelial cells: spindle/stellate-shaped → a lot of forms (sheets, clumps & strands). Myoepithelial Cs: spindle/stellate → sheets, clumps & strands c) Some myoepithelial cells resemble plasma cells , called Plasmacytoid cells Plasmacytoid Cs |Page7 Wondershare PDFelement d) Some myoepithelial cells undergo squamous metaplasia (transform into squamous cells), and may develop keratin, so we can see keratin inside pleomorphic adenoma. 4- Stroma (which helps in diagnosis) “MOST important component”: Seen in different forms: a) Fibrous and may undergo hyalinization. b) Myxoid (mucoid material around the cells): when there is an increase in the amount of mucoid material, we may find like a bit of fluctuation of PA. The surgery will be difficult, because the surgeon may induce rupture of the tumor, then the tumor cells will contaminate the surgical field and cause recurrences , so the presence of a large amount of mucus within the gland which has the tumor increases the risk of local recurrent. c) Chondroid, resemble hyaline cartilage. d) Bone: Even bone could be present. Fibrous/hyalinization Myxoid Bone Chondroid |Page8 Wondershare PDFelement 013 ‫شرح مساعد من شيت‬ ➢ Warthin tumor: - Second most common. - Origin: it most likely arises from epithelial duct cells which are entrapped within the lymph nodes in the salivary gland, that’s why it is sometimes called Adenolymphoma, although it is wrong, because actually this is not a lymphoma, it is an adenoma because the lymphatic tissues are normal. ❖ Clinically : - 7% of salivary gland tumors. - Occurs almost exclusively in the parotid gland, 9% of parotid tumors. - Slightly More common in females in recent studies, although historically they said that it is more common in males. - Bilateral in some cases (10%). - Sometimes, multiple in the same gland. - Usually, it appears in the tail of the parotid gland, near the angle of the mandible, you may diagnose it as cervical lymphadenopathy. - Smokers have an 8 folds greater risk than non-smokers |Page9 Wondershare PDFelement - Grossly: The tumor is encapsulated (fibrous capsule) and the content is multi irregular cystic spaces, containing mucoid material, and from the wall of tumor there is papillary projections to the cystic spaces. - Microscopically: • The papillary projections are composed of double layer of epithelial cells; Basal cuboidal Cells & superficial columnar Cells. The epithelial cells show granular eosinophilic cytoplasm (called Oncocytes). **Oncocytes: cells show large granular eosinophilic cytoplasm • Supported by a connective tissue containing normal lymphoid tissue with active germinal centers, so you will see lymph nodes and inside them an epithelial proliferation. | P a g e 10 Wondershare PDFelement ➢ Canalicular adenoma: - Almost all cases develop in the upper lip (compared to the other tumors that usually develop in the parotid gland). - It causes a Localized persistent swelling in the upper lip. - it is Rare in the major salivary gland. - Histologically: 1) Thin capsule around the tumor. 2) Composed of epithelial cells arranged in elongated anastomosing cords (like canals), because of this it is called “canalicular adenoma”. These epithelial cells are single layered cuboidal or sometimes columnar ductal cells. 3) This tumor is characterized by degeneration of delicate stroma forming the tissue around the epithelial cells, usually there is a degeneration of these stroma causing multiple cystic spaces around the epithelial cells. Ca | P a g e 11 Wondershare PDFelement ➢ Basal Cell Adenoma: - Represent 1-2% of all salivary gland tumors. - 75% in parotid and the rest (20%) in Upper Lip. - Clinically, similar to pleomorphic adenoma: slowly enlarging, rubbery swelling, painless and don’t cause ulceration or any neural manifestations. - Histologically : 1) Well-encapsulated 2) Composed of basaloid cells of different forms; solid, trabecular, tubular, membranous. ➢ Oncocytoma: - Composed of epithelial cells like what we saw in the Warthin tumor (Oncocytes). - Oncocytes: abnormal Cell with prominent eosinophilic granular cytoplasm. - Mainly in the parotid gland. - Clinically, similar to pleomorphic adenoma (you can’t differentiate between them). - Could be bilateral as Warthin tumor (both parotid for example). - Histologically : 1) Thin capsule. 2) Oncocytes arranged in solid sheets/cords or acinar pattern. 3) Lacks a fibrous stroma. so, mainly they are composed of oncocytes. | P a g e 12 Wondershare PDFelement ➢ Ductal papillomas: - Rare - There is proliferation of the epithelium forming the ducts of the glands. So, sometimes they present with signs of blockage to the salivary gland, for example if it develops in major gland, it will give the signs and symptoms of sialothiasis (salivary stones), but if you take a radiograph you won’t find any stones with sialography and other investigation you will confirm the presence of this proliferation from the lining of the duct. - Different types : (not mentioned in lecture, only in slides) 1) Sialadenoma papilliferum, clinically similar to squamous papilloma. 2) Inverted ductal papilloma. 3) Intraductal papilloma, usually inside the major ducts giving signs of obstruction similar to salivary stones. Malignant tumors -Rare in the head and neck. ➢ Mucoepidermoid Carcinoma : - Commonest malignant tumor of all salivary glands and the commonest malignant tumor of the major salivary glands. - 4th and 5th decade of life. The most common malignant minor salivary gland tumor is adenoid cystic carcinoma - 50% of its cases develop parotid, 20% of cases develop in the palate. - Represent 10% of all Salivary gland tumors. - 10-15% of minor Salivary gland tumors are Mucoepidermoid carcinoma. | P a g e 13 Wondershare PDFelement - Clinically: can present similar to pleomorphic adenoma, but can present with signs of malignancy; ulceration, necrosis, invasion, destruction to the surrounding tissues and neural changes. For example: if developing in parotid → can cause paralysis of the face If developing in palate → anesthesia or paresthesia can occur in the palatal region . - Grossly: 1) No capsule localizing the tumor, not well defined. 2) There is invasion with the surrounding tissues. - Histologically: 1) Composed of 3 types of cells: mucous cells, squamous cells and intermediate cells that can change into the mucous or squamous. 2) These epithelial cells are arranged in Nests, diffuse sheets and form cystic spaces (cystic spaces are lined by mucous cells). ➢ Mucous, squamous & intermediate Cs | P a g e 14 Wondershare PDFelement - According to the grade, we have 3 grades: a) Low grade /well-differentiated tumor: they are mainly composed of mucous cells and squamous cells. You will find a lot of cystic spaces and a lot of mucus cells lining these spaces. You don’t find sings of malignancy like pleomorphism, hyperchromatism or increasing the mitotic activity. The local recurrence rate ( LRR) in the low grade < 10%. The 5-years survival (5-year SR) = 95% of the cases live more than 5 year. b) Intermediated grade tumor. c) High grade tumor/or poorly differentiated: composed mainly of squamous cells and intermediate cells and lack of mucous cells. Also lack of cystic spaces. You will find signs of malignancy, sometimes you need special stains to see mucus between the epithelial cells to confirm the diagnosis of Mucoepidermoid Carcinoma. Prognosis → not good, LRR=80%, 5-year-SR<30%. ➢ Adenoid cystic Carcinoma: - Second most common and the most dangerous tumor in salivary gland - 30% of minor SG tumors (most common in minor SG) | P a g e 15 Wondershare PDFelement - 3-6% of parotid SG tumors (NOT the most common in major SG, Mucoepidermoid is the most). - May resemble pleomorphic adenoma clinically, but actually adenoid cystic can causes Pain, ulceration, facial paralysis and paresthesia, anesthesia in the region. So, it can give the signs of malignancy clinically. - Histologically, it causes three main patterns: 1) Cribriform pattern: the most common histological pattern. - Composed of oval nests of cuboidal or polygonal Cells with hyperchromatic nuclei (dark stained nuclei). - Containing Islands with multiple microcystic spaces and Eosinophilic or basophilic substance. - This appearance resemble “Swiss cheese” or “honeycomb”, so Swiss cheese appearance helps in diagnosis of adenoid cystic Ca. Eosinophilic or basophilic substance. - A characteristic of this tumor is Neurotropism: spread of the tumor in the lymphatic spaces around the nerves (invasion around the nervesperineural invasion-) for a long distance away from the main tumor which increases the local recurrence rate. | P a g e 16 Wondershare PDFelement 2) Tubular pattern: Small ductal elements lined by basaloid Cells. 3) Solid pattern: Solid nests of basal Cells. - The worst prognosis. - Prognosis: - Generally had a poor prognosis because as we said before it spreads around nerves, also it spreads in the marrow spaces without initial resorption, so it can spread for long distance around the main tumor in the marrow spaces, that increases the LRR and poor survival. - 5-y SR: 75%, 10-y SR: 40%, 20-y SR: <20% - Solid - Distant spread to the lungs is more common than lymph nodes metastasis (may cause distant metastasis before regional metastasis). ➢ - Acinic cell Carcinoma Rare, not common, not important. Mainly affect the parotid. Can be seen in any age. Similar to the pleomorphic adenoma. Generally low-grade and slow growth potential. Low-grade: 80-100% 5y-SR Poorly differentiated: 65% 5y-SR | P a g e 17 Wondershare PDFelement - Histologically: • Large Cells and granular basophilic cytoplasm often in acinar pattern (so the name is acinic cell carcinoma). • Arranged in solid, microcystic, papillary cystic, follicular pattern. • Very scanty stroma. • W-d (well-defined )but lobulated. • Some are poorly differentiated. ➢ Carcinoma ex pleomorphic adenoma: - Malignant tumor that develops in a long standing pleomorphic adenoma. - Particularly with : 1) pleomorphic adenoma presents for long period (1015 years). 2) Those with history of local recurrence. - Clinically: PSA with signs of malignance: pain, palsy, ulceration. - Mostly in the parotid gland. - Histologically: - Carcinoma features (different types of carcinoma; adenoid cystic, Mucoepidermoid, squamous cell carcinoma and others) adjacent to pleomorphic adenoma. - adenoCa, Undifferentiated Ca | P a g e 18 Wondershare PDFelement - prognosis: Depends on whether the carcinoma is inside the pleomorphic adenoma capsule or not, if still inside: good prognosis, if it spreads outside: bad prognosis. ➢ Polymorphous low-grade adenoCa: - mainly seen in the palate. - rare to cause metastasis to the regional lymph nodes (only 6-10 % of the cases) - Histologically : 1) Composed of cytologically benign-looking pale-staining cells. 2) Arranged in different forms (so it is called polymorphous);Tubular, lobular, papillary, papillary cystic, Cribriform in some areas similar to Adenoid cystic Carcinoma. ➢ • • • • • Other Ca: AdenoCa (NOS: not otherwise classified). Basal Cell AdenoCa SCC Sebaceous Ca Undifferentiated Ca Also, we can find malignant tumors that develop from the stromal tissue of the salivary gland, for example lymphoma and other malignant tumors. | P a g e 19