Download MBBS Dermatology PPT 20 Naevi Tumors Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Dermatology PPT 20 Naevi Tumors Lecture Notes


NAEVI AND TUMORS

Nevus

? Circumscribed, non-neoplastic skin or mucosal lesion,
? usually present at or soon after birth.
? Term should always be qualified according to the cell or tissue of

origin, for example "connective tissue nevus" or "vascular nevus".

? Nevi generally represent clones of genetically altered cells arising

from mosaicism.
Benign tumor

? A localized proliferation of cells of one type,

? which has some degree of autonomous control of growth,

? but a normal differentiation.

In situ tumor

? A localized collection of morphologically malignant epidermal cells,

? which have still not invaded the basement membrane

? so it essentially applies to epidermal tumors.


Malignant tumor

? A collection of morphologically malignant cells

? with full capacity to metastasize to lymph nodes and other organs.


? Others:
? Underlying skin diseases
? oculocutaneous albinism
? Xeroderma pigmentosum
? Epidermodysplasia verruciformis
? Chronic venous ulcers



EPIDERMAL TUMORS AND NEVI

? SEBORRHEIC KERATOSIS
? Benign epidermal tumor,

? seen after age of 50.

? Morphology: Multiple, well-defined, hyperpigmented papules with a

"stuck on" appearance, a greasy surface, and keratinous plugs.

? Sites: Face, trunk, and upper extremities.

? Treatment: Can be left alone, remove if cosmetically disfiguring.

Biopsy if diagnosis is in doubt (to rule out malignant melanoma).

? Biopsy- horn pseudocysts


? small black papules, limited to

the upper part of face.


?

Skin Tags

? Familial
? Associated with obesity.
? Acanthosis nigricans.
? Diabetes.
? Soft, skin-colored or pigmented, pedunculated papules
? Neck, axillae, and groins.
? radiofrequency


Melanocytic Nevus

Congenital melanocytic nevi

? Derived from epidermal melanocytes and nevus cel s have a predilection

for deeper penetration.

? Present at birth.

? single,multiple.

? Color varies from brown to black

? lesions darken and enlarge as the child grows.

? With age, the lesions also become raised and develop rugosities

(cerebriform appearance).

? Coarse hair develops in 90% of lesions

?
? Giant lesions are usually seen on the trunk and because they may

cover large areas of the trunk, are called "bathing trunk nevi".

? Complications: potential for malignant transformation is definitely

more in giant congenital melanocytic nevi (bathing trunk nevi).

? Meningeal involvement and spina bifida, seen in lesions located over

vertebral column.





ACQUIRED MELANOCYTIC NEVI

JUNCTIONAL MELANOCYTIC NEVUS


COMPOUND MELANOCYTIC NEVUS

INTRADERMAL MELANOCYTIC NEVUS


OTHERS

? MONGOLION SPOTS
? Bluish ill-defined macules
? Lumbosacral region.
? Regress by age of 4 years


?

? NEVUS OF OTA
? Present at birth.
? Or appears in infancy.
? Macular pigmentation, which has two components: More prominent

slate grey hyperpigmentation due to dermal melanocytes. Brownish

epidermal pigmentation.

? Distribution along the maxillary division of the trigeminal nerve.
? Pigmentation of sclera (slate gray) and conjunctiva (brown) often

present


?

? Halo nevus or Sutton's nevus:
? Melanocytic nevus which develops a halo of depigmentation
? over period of many years, the nevus involutes and
? the depigmented halo repigments.


COMPLICATIONS

? INFLAMMATION
? MALIGNANT CHANGE-
? The following changes in a melanocytic nevus are suspect and

warrant a biopsy:

? Change in size and pigmentation.
? Change in shape and contour.
? Itching, inflammation, ulceration, and bleeding.

?


Verrucous Epidermal Nevus ? localised/

generalised

Variants

? ILVEN


? NEVUS COMEDONICUS

? NEVUS SEBACEOUS


?

Becker's Nevus

? Common condition.
? More frequent in men.
? Begins shortly before, at or after puberty.
? Appears as a hyperpigmented (light-dark brown) patch, which has a

characteristic splashed appearance.

? Over period of time, coarse dark hairs appear on the lesion
? Chest and shoulders.


Epidermoid and Trichelemmal Cysts

? freely mobile over underlying

structures

? tethered to the skin.
? Characteristically, have a central

punctum through which cheesy

material can be expressed

? Sites

? Complications

? Epidermoid cyst: Face, upper

? Secondary infection.

back, and retroauricular region

? Rupture in the dermis and

induce a foreign body reaction.

? Trichilemmal cyst : Most

? Dystrophic calcification

frequent on the scalp.


? MILIA:
? small subepidermal keratin cysts.
? small, firm, white papules,

which are less than 2 mm in

diameter.

? De novo on the face
? At sites of healed subepidermal

blisters e.g., bullous pemphigoid

Premalignant Lesions

? cutaneous horn
? keratoacanthoma
? Bowen's disease
? actinic keratoses
? arsenical keratoses




cutaneous horn

?Cutaneous horn (cornu cutaneum)

? A conical hypertrophic protuberance emanating from a skin-

colored to erythematous papular base

? Height at least one-half of the largest diameter

? Thirty-eight percent to 40 percent of all cutaneous horns

represent AKs


? Is a morphological diagnosis.
? Occurs secondary to:
? Epidermal nevus.
? Warts.
? Seborrheic keratoses.
? Rarely, underlying squamous cell carcinoma.

keratoacanthoma

? Rapidly growing, skin-colored

nodule, which develops a central

horny plug ; the plug falls off to

leave a crater.

? Most lesions resolve

spontaneously, leaving a

depressed (cosmetically

unacceptable) scar.

? Few (very few!!) transform into

squamous cell carcinoma.
Keratoacanthoma

? Solitary or multiple
? rapid growth
? 1 to 2.5 cm
? ulcer with keratinous material
? spontaneous resolution

Bowen's Disease

? Carcinoma in situ
? erythematous plaque
? irregular borders
? enlarging psoriasiform plaque
? indentations (reniform margin)


BOWEN'S DISEASE

? A: psoriasiform plaque, showing

irregular indentations.

? B: infiltration of the lesion

indicates development of

squamous cell carcinoma


? Treatment
? Excision,
? cryotherapy, or
? topical 5-fluorouracil (5-FU).


? Actinic keratoses: pink irregular

macules and papules with dry

adherent scales.

? middle aged and elderly.
? Face, scalp, and dorsae of hand.
? Suspect transformation into

squamous cell carcinoma (a rare

occurrence), if the lesion

enlarges rapidly, ulcerates or

bleeds.

? arsenic keratoses: multiple corn-

like papules.

? rain drop pigmentation
MALIGNANT EPIDERMAL TUMORS

? BASAL CELL CARCINOMA

? SQUAMOUS CELL CARCINOMA

? MALIGNANT MELANOMA

1. BASAL CELL CARCINOMA

? The most common cancer

affecting humans

? Slow growing

? At least 75% first tumours are on

the face

? Relatively `benign' in most cases

? but if left untreated can be

disfiguring and life threatening
Basal Cell Carcinoma

? Raised, with pearly border
? prominent vasculature
? ulceration
? nodular most common

TYPES OF BCC

NODULAR
? Usually begin as a small

pink `pearly' papule

? Develop a depression in

the centre

? Rolled edge

? Overlying telangiectasia
Superficial Basal Cell

? Scaly patches
? irregular borders
? extremities, less common in head

and neck

MORPHOEIC

? White or waxy

? Always on face

? Presents as a spontaneous `scar'

? Margins are usually much wider than

what is clinically visible


Pigmented BCC

? Basal Cell Carcinoma----

histopathology is diagnostic

? Cells resemble those of stratum

basale

? peripheral palisading

? stromal retraction
? Course
? Slowly progressive,
? locally invasive (especially noduloulcerative variant) neoplasm,
? eating into underlying structures like cartilage or bone, if left

untreated.

? Lymphadenopathy and distant metastasis do not occur.

? Surgical excision is treatment of choice in most cases.

? All variants of BCC except the morphoeic variant are excised with a

0.5 cm of skin margin.

? Morphoeic variant is excised with wider margin (up to 2 cm) because

the lateral extent is often indistinct.


Squamous cell carcinoma

? Etiology:
? Damaged skin (photodamaged/scarred/ulcerated skin/leucoplakia/

erythroplasia),

? topical and systemic carcinogens- Pitch tar, mineral oils, and inorganic

arsenic

? human papilloma virus
? immunosuppression - HIV
? Certain rare genetic disorders, with defective DNA repair

mechanisms, such as xeroderma pigmentosum

? A: raised ulcer with indurated

base and everted margin

(cauliflower-like) on the lower lip.

? B: raised ulcer with indurated

base and everted margin at site

of radiation dermatitis.
? Metastases
? Lymphadenopathy: Regional lymphadenopathy. Nodes hard and

sometimes fixed to underlying structures and tethered to skin.

? Visceral metastases: Infrequent.

? scc


? characteristic histology.
Malignant Melanoma

? Etiology:

Clinical variants :

? Multifactorial.

lentigo maligna melanoma,

? Actinic damage important.

superficial spreading melanoma

? Evidence of nevi in 25% of

(SSM),

patients with MM.

acral lentiginous melanoma, and
nodular malignant melanoma

(NMM).
SSM most frequent while NMM is

the most aggressive.

? Asymmetrical pigmented nodule,
? Border irregularity,
? Color variability,
? Diameter >0.5 cm,
? Elevation irregularity.


Subungual

Metastatic melanoma

melanoma


? histological grading using

Breslow's method.

? measures the vertical distance

(in mm) from granular cell layer

to the deepest part of tumor,

using a microscopic micrometer.

? prognostic predictor.

Benign Tumors of Skin Appendages


Malignant Tumors of Skin Appendages

Paget's Disease

? Paget's disease of breast:
? sharply marginated plaque with

a slightly raised edge and an

irregular outline.

? If the crusts are removed, a red,

glazed, moist surface is revealed.

? Note destruction of nipple.

Benign Tumors and Nevi of Dermis


? Port-wine stain: deeply

erythematous, telangiectatic

slightly bosselated lesion on the

face.

? Usually present at birth.

? Salmon patch

? Is a capil ary malformation

? Commonest vascular malformation

present at birth.

? salmon patch involutes by the age

of one.

? Presents as telangiectatic macules.

? Nape of neck, forehead, and

eyelids.

? Treatment None required.


? Venous malformation: a soft

compressible bluish swelling,

which increases in size when

dependent

? Lymphatic malformations
? Usually present at birth.

? Characterized by a cluster of

thin walled vesicles (resembling

frog spawn).


Infantile hamangioma

? Lesion appears within a few

weeks of birth and grows for a

few months.

? Spontaneous regression occurs

with minimal atrophy in most

patients.

? Soft, brightly red (strawberry

colored) nodule with pale

stippling indicating resolution

? Complications:

? Treatment

? Large swellings near orifices

? Small lesions: Resolve

(oral, nasal, anogenital)

spontaneously.

interfere with function.

? Large symptomatic lesions:

? Bleeding may follow trauma.

? Systemic steroids

? Ulceration especially in large

? Propranolol

lesions and in intertriginous area. ? Lasers: pulsed dye laser in

residual lesions.




Beningn acquired

hemangioma/ pyogenic

granuloma


Malignant Tumors of Dermis

Cutaneous T Cell Lymphoma (Mycosis Fungoides)
? Lymphoma of helper T cel s.

? Initial patch stage of wel -defined, bizarre

shaped, atrophic patches; poikiloderma

? later infiltrated plaque stage and then

? tumor stage with aggressive course.

? Characteristic histology with presence of

atypical cel s (Pautrier's microabscesses);

epidermotropism

? Treatment: Early stage: Topical steroids,

topical nitrogen mustard, PUVA, acitretin

and electron beam treatment.

? Tumor stage: Chemotherapy.

? Others:
? LCH
? Kaposi sarcoma
QUESTIONS (please answer in one word)

? 1. Horn pseudocysts are a feature of ?
? 2. Virus which is implicated in the pathogenesis of skin malignancies-
? 3. Bathing trunk nevus is a type of-
? 4. melanocytic nevus surrounded by a depigmented halo is
? 5.Name a premalignant lesion of skin
? 6.Pautrier microabscesses are seen in

? 7. What is the diagnosis in case of pigmented macules present over

left cheek distributed over maxillary division of trigeminal nerve-

? 8. Which of the malformation is most likely to involute

spontaneously?

? 9. Grouped open and closed comedones arranged linearly are seen in
? 10. . Breslow's method is used for histological staging of

This post was last modified on 07 April 2022