Oral pathology sheet # 11 - Mohammad Bustani

by **Shadi Jarrar** 3/8/2011, 7:54 pm

بسم الله الرحمن الرحيم

________________________________
http://www.4shared.com/document/dmUmMBYU/Oral_Patho__11.html
________________________________

Lecture # 11 ((31.07.2011))

بسم الله الرحمن الرحيم
Connective Tissue Lesions

Last lecture we started talking about connective tissue lesions. Today we will continue talking about papillary hyperplasia of the palate and then we will talk about connective tissue tumors.

Papillary hyperplasia of the palate (Inflammatory Papillary hyperplasia)

Clinically:
affects the hard palate, presented as numerous (multiple) papillary small, tightly packed projections, 3-4 mm in diameter each (small), over part or all of the hard palate. It might be surrounded by red and edematous mucosa that is described as " Field of confluent reddish mushrooms ".

Etiology:
Mainly, it is poor oral hygiene with a loose or ill fitting denture and sleeping while wearing the denture, so it happens mainly in the edentulous patients under the upper denture.
And it might be associated with a low-grade bacterial or candidal (fungal) infection under the denture.
* Rarely seen in patient with high palatal vaults or mouth breathers which cause irritation to the mucosa resulting in papillary hyperplasia *

Histologically:
All of CT hyperplasias have almost the same appearance (granulation tissue with surface epithelium).
So, the core is composed of dense fibrous tissue (in the late stage) or granulation tissue (in the early stage), with chronic inflammatory cell infiltrate (CICI). The surface epithelium might be atrophic, acanthotic (hyperplasia) or it can be pseudo-epitheliomatous hyperplasia (which looks like invasive squamous cell carcinoma, so it might be confused with it in biopsy diagnosis and must be differentiated clinically.

Connective tissue tumors

They are rare tumors. But any type of connective tissue may result in benign or malignant tumors.

1) Fibrous tissue
- Fibroma:
True fibromas are very rare; usually we deal with fibro-epithelial polyps which we have already discussed. Both are similar but one is tumor and the other is CT hyperplasia which is caused by chronic irritation, while the tumor is a result of genetic mutations. Another differences, that the fibro-epithelial polyps reaches a certain size and then remains the same while the tumor keeps growing larger and larger. Fibroma is capsulated while fibro-epithelial polyps are not.

- Benign and Malignant fibrous histiocytoma:
Rare lesions, derived from cells with fibroblastic and histiocytic differentiation. They are aggressive lesion but rare so they are not very important.

- Fibrosarcoma:
Also rare, we find it usually in children. Clinically, shows signs of malignancy (like ulceration, destruction …). Histologically, it is composed of spindle-shaped cells with histological signs of malignancy that might be well-differentiated or poorly-differentiated.

2) Vascular tissue
there is some common lesion that we will stress on:
- Haemangioma and Vascular malformation:
it is mandatory to differentiate between these two concepts since some textbooks use them interchangeably.
Haemangioma is common lesion that is not present at birth, appears within the first 2 months of age. Go through rapid growth and then gradual involution that 50% vanish before 5 years of age and 90% by age of 10.
While if the lesion was present at birth and didn’t disappear with advancing age, it shouldn’t be called Haemangioma but it should be described as vascular malformation.

Haemangiomas have more than one type histologically and clinically. Capillary type (size of capillaries) or Cavernous type (size of veins) or mixture between these 2 types. Vascular malformation could be venous or capillary or arterio-venous (which is continuous connection between arteries and veins without the presence of capillaries and it is the most dangerous and may cause severe bleeding upon trauma or incision in that area).

Clinically:
Haemangiomas may be found in the head and neck (common site for Haemangioma is the skin of head and neck).
May be flat or raised or multi-nodular. It is asymptomatic, soft lesion. Its color is reddish, blue or purple.
A clinical test to confirm diagnosis, as we apply pressure on the lesion, the color turns pale (blanch) because the blood leaves the lesion so it appears normal, this is called blanching on pressure.
Might affect the tongue, buccal mucosa or the lips.
May be symptomatic upon trauma during dental procedures, bleeding could result. Sometimes, thrombosis may happen in these lesions with calcification of the thrombus that can be palpated.

Histologically:
composed of proliferation of epithelial cells without evidence of vascular formation (you can't find a lot of blood vessels). Capillary Haemangioma vs. cavernous Haemangioma (large vein-like lesion contains RBC's).

Dental aspects:
May be found inside the oral cavity or on the lips, tongue ( it is one of the cause of macroglossia) , buccal mucosa and palate.
Sometimes it might be intramuscular, within the muscles of the tongue or muscles of mastication (masseter muscle).
May affect salivary glands (parotid gland).
And can be found inside the mandible or maxilla (within bone). A dangerous site because of bleeding after extraction of teeth in the same area of the lesion.

Some unique types of these lesions:
- Port-wine stain:
--- unique type of capillary vascular malformation on the face. ( it doesn't disappear with advancing age).
--- affects usually the dermatome of the ophthalmic, maxillary or mandibular branch of trigeminal nerve.
--- well defined with irregular margin, unilateral lesion.
--- purple in color.
--- usually it is flat but we may find some nodular lesion

- Sturge-Weber syndrome:
--- it is the same as port-wine stain with other manifestations, which are; ipsilateral intracranial Haemangioma (on the same side of lesion) and we may find calcifications within it ,, epilepsy (convulsion) ,, contralateral (on the opposite side) hemiplegia ,, mental retardation ,, lesions within the oral cavity (affecting oral mucosa or bone) ..

- Hereditary haemorrhagic Telangectasia:
--- “Rendu-Osler-Weber syndrome”--- Autosomal dominant vascular lesion (there is family history).
--- Defect in vascular walls so we can find multiple vascular dilations, small knots -like lesion (telangiectases).
--- Found on skin, mucous membranes including oral cavity, respiratory tract, gastrointestinal tract and internal organs.
--- These lesions may cause continuous mild bleeding, which results in iron-deficiency anemia.
--- Clinically presented as multiple reddish papules. One of the early signs is epistaxis (bleeding of nose) as it affects the nasal mucosa.
--- Dental aspects, as it can be found in the oral mucosa, tongue and lips. Any trauma during dental treatment may cause prolonged hemorrhage. In addition, the patient may show oral manifestation of anemia (like; ulceration, candidal infections …).

-Angiosarcoma & Kaposi’s sarcoma:
--- We will talk about Kaposi's sarcoma later on.
--- Angiosarcoma is very rare to discuss.

3) Lymphatic tissue
-lymphangioma:
- Almost the same as Haemangioma but instead of blood vessels , it is lymphatics containing lymph instead of RBC's.
- Less common than haemangioma.
- Congenital malformation of the lymphatic system in a part of the body (not continuous with the general lymphatic system of the body).

Clinically:
-may be found at birth or early childhood (although it is congenital).
- Can affect any part of the body, but the tongue is a common site (causing macroglossia).
-can be found superficially so it is easy to be diagnosed or deep, which is difficult to be diagnosed.
- Superficially positioned lymphangioma are pale in color and translucent, like vesicle (contain clear fluid).
- Smooth or some nodularity may be found on the surface.
- May cause enlargement of the affected organ (like the tongue).
- If it was subjected to trauma, it may result in bleeding inside this lesion and may look like haemangioma clinically. So differential diagnosis is needed in such lesion when there is history of trauma.
Histologically:
-Normal looking lymphatic vessels, that may be found very superficial (close to epithelium) so the epithelium, covering it, is atrophic so it appears clinically as vesicular lesion containing clear fluid that can be misdiagnosed with vesiculobullous disease.
-Capillary vs. cavernous type of lymphangioma.

- Cystic hygroma:
--- cavernous type of lymphangioma (large vessels) may affect the Lateral side of neck and called Cystic hygroma.
--- Very large lymphatic vessels and infiltration within the neck muscles is taking place which is difficult to treat.
--- Quite massive in size, fluctuant & covered by normal skin
--- Appears in the first or second year of life.
--- Dental aspects, may be extended to the floor of the mouth and oral mucosa within the oral cavity.

4) Adipose tissue (fatty tissue)
-lipoma:
- benign lesion

Clinically:
- It appears as well-defined soft lesion.
- Yellowish in color if it is close to the surface.
- Movable because it is capsulated. Just like normal lymph nodes.
- Asymptomatic, slowly growing lesions.
- Affects adults, found in buccal mucosa and tongue (as the most common sites).
- After excision, if u put the lipoma in formalin, it will floats on top (because it is fatty tissue) and this helps in diagnosis.

Histolgically:
-Normal looking fatty tissue.
- Well defined mass of mature adipose tissue surrounded with thin fibrous capsule.
--- Fibrolipoma: lipoma that contains a lot of fibrous tissue. But clinically they are the same.

- Herniated buccal fat pads:
-Normally, we can find buccal fat pads in the face. Upon trauma, herniation to the oral cavity may result.
- More prominent in infants and young children.
- as an example, if a trauma to the buccinators muscles happened the adipose tissue may be herniated to the oral mucosa and looks like swelling in the buccal mucosa, so It might be confused with lipoma.
- History of trauma helps in differentiation. And, since herniated buccal fat pads are caused by trauma, you may find infection, ulceration and necrosis.

-Liposarcoma:
- very rare in the head and neck region, it is mainly found in the extremities.

5) Neural tissue

-Neurofibroma:
- Benign lesion.
- The origin is from the Perinural fibroblasts.

Clinically:
- it may affect tongue, buccal mucosa, lip or it may be intra-bony (originating from the inferior alveolar nerve in the mandibular canal).
- well defined clinically, painless, presented as sub-mucosal nodules so it is hard to be diagnosed clinically. So differential diagnosis is very important in these lesions ((it could be lipoma, neurofibroma, and schwannoma)) and histopathology is used for differentiation.
-the majority is solitary (1 lesion), but could be part of Multiple Neurofibromatosis.
-So, if u found more than one neurofibroma in the oral cavity, it will be associated with skin lesion called Multiple Neurofibromatosis.

- Multiple Neurofibromatosis:
- 2 types : type 1 - called Von Recklinghausen Disease.
type 2 – in CNS (mainly).

- Von Recklinghausen Disease:
--- multiple neurofibromas affecting skin (superficial).
--- Autosomal dominant
--- it may be severe in the face region causing disfigurement, some lesions may be large causing enlargement in the head and neck so it is called elephantiasis neuromatosa.
---nodules may show pigmentation called Café-au-lait spots, and these are easy to be diagnosed.
--- 25% of these syndromes (Von Recklinghausen Disease) may show oral lesions (multiple neurofibromas in the oral cavity) as nodular or diffuse swellings in the oral cavity or even intra-bony lesions (in mandibular canal region).
--- those lesions that are associated with syndromes may develop malignancy in 5-15 % of the cases.

Histologically:
- Circumscribed lesions but may be diffuse and difficult to locate the border, because it is not encapsulated.
- shows haphazardly spindle-shaped cells (cells that look like fibroblast). With fine sinuous collagen fibers.
- We may find mast cells (we use special stains for mast cells that will help us in diagnosis) and we can find nerve fibers within the lesion.

-- note ..
-- there is one piece of information that I didn’t find in the slides or in the book , you can find it between the two stars in the first page; here is the link where I checked it from , it seems useful too .. http://www.maxillofacialcenter.com/BondBook/softtissue/paphyperplasia.html
-- good luck

CORRECTIONS ARE WELCOMED

Written by: Mohammad H. Bustani

Oral Pathology Lect. #11 on 31.07.2011

Dr. Faleh Al-Sawaeer