PBLI- 14jan11
Skin lesion, back, excised
PBLIs (Problem-based Learning Issues)
1. What are terminologies used by dermatologists in describing skin lesions – macules, papules, etc.?
2. What is the difference between actinic and seborrheic keratosis?
3. What is shave excision?
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Name: Rohanifah P. Sarosong ( MDH Surgery PGI) – submitted 14jan12
I.Descriptions of Skin Lesions
Description of Primary Skin Lesions
| Macule: A flat, colored lesion, <2 cm in diameter, not raised above the surface of the surrounding skin. A “freckle,” or ephelid, is a prototype pigmented macule. |
| Patch: A large (>2 cm) flat lesion with a color different from the surrounding skin. |
| Papule: A small, solid lesion, <0.5 cm in diameter, raised above the surface of the surrounding skin and hence palpable |
| Nodule: A larger (0.5–5.0 cm), firm lesion raised above the surface of the surrounding skin. |
| Tumor: A solid, raised growth >5 cm in diameter. |
| Plaque: A large (>1 cm), flat-topped, raised lesion; edges may either be distinct (e.g., in psoriasis) or gradually blend with surrounding skin |
| Vesicle: A small, fluid-filled lesion, <0.5 cm in diameter, raised above the plane of surrounding skin. |
| Pustule: A vesicle filled with leukocytes. Note: The presence of pustules does not necessarily signify the existence of an infection. |
| Bulla: A fluid-filled, raised, often translucent lesion >0.5 cm in diameter. |
| Wheal: A raised, erythematous, edematous papule or plaque, usually representing short-lived vasodilatation and vasopermeability. |
| Telangiectasia: A dilated, superficial blood vessel. |
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| Description of Secondary Skin Lesions |
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| Lichenification: A distinctive thickening of the skin that is characterized by accentuated skin-fold markings. |
| Scale: Excessive accumulation of stratum corneum. |
| Crust: Dried exudate of body fluids that may be either yellow or red |
| Erosion: Loss of epidermis without an associated loss of dermis. |
| Ulcer: Loss of epidermis and at least a portion of the underlying dermis. |
| Excoriation: Linear, angular erosions that may be covered by crust and are caused by scratching. |
| Atrophy: An acquired loss of substance. In the skin, this may appear as a depression with intact epidermis or as sites of shiny, delicate, wrinkled lesions |
| Scar: A change in the skin secondary to trauma or inflammation. Sites may be erythematous, hypopigmented, or hyperpigmented depending on their age or character. Sites on hair-bearing areas may be characterized by destruction of hair follicles. |
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II.Seborrheic keratosis versus Actinic keratosis
| SEBORRHEIC KERATOSIS |
ACTINIC KERATOSIS |
| Definition:- most common benign tumor in older individuals. Seborrheic keratoses have a variety of clinical appearances, as seen in the images below, and they develop from the proliferation of epidermal cells. Although no specific etiologic factors have been identified, they occur more frequently in sunlight-exposed areas. |
-is a UV light- induced lesion of the skin that may progress to invasive squamous cell carcinoma. It is by far the most common lesion with malignant potential to arise on the skin. |
| History: – Slow enlargement with increasing thickness and the gradual development of new lesions.- as they initially grow, they develop a velvety to finely verrucous surface, followed by an uneven warty surface with multiple plugged follicles and a dull or lackluster appearance
– Typically have an appearance of being stuck on the skin surface.
– The color of the lesions can vary from pale brown with pink tones to dark brown or black |
History: – seen almost exclusively in whites, especially those with skin phototypes I and II.- The incidence increases with each decade of life
– men have a slightly increased frequency of actinic keratosis.
– Patient who are immunosuppressed following organ transplantation are at markedly increased risk of developing actinic keratosis. |
| Physical : – Initially one or more sharply defined, light brown, flat lesions develop with a velvety to finely verrucous surface.- initial size is usually less than 1 cm, but the lesions can grow to several centimeters or more. With time, the lesions become thicker and have an appearance of being stuck on the skin surface.
– Fully developed seborrheic keratoses often are deeply pigmented and do not reflect light.
– Many lesions show keratotic plugging of the surface.
– Some lesions are covered by an adherent greasy-appearing scale and are raised above the surface of the skin. Seborrheic keratoses can feel soft and greasy.
– The shape is round to oval, and multiple lesions may be aligned in the direction of skin folds.
– The smallest lesions are placed around follicular orifices, especially on the trunk.
– Most seborrheic keratoses have fewer hairs than the surrounding skin that they come from.
– Sometimes the lesions can grow large, with individual seborrheic keratoses reaching up to 35 X 15 cm.
– Epiluminescent surface microscopic examination of seborrheic keratoses reveals globulelike structures. The globule like structures in seborrheic keratoses are due to intraepidermal horn cysts filled with cornified cells containing melanin. They resemble the brown globules observed in melanocytic neoplasms, which are due to nests of melanocytes at the dermoepidermal junction.
– Irritation can cause swelling and sometimes bleeding, oozing, and crusting and a deepening of the color due to inflammation.
– Seborrheic keratoses may become red-brown in color when they become inflamed.
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Physical : – The lesions arise in areas of long-term sun exposure including the face, ears, bad scalp in men, and the dorsal forearms and hands.- Actinic keratoses begin as small rough spots that are easier felt than seen, often described as being similar to rubbing sandpaper. With time, the lesions enlarge, usually becoming red and scaly; most are only 3-10 mm, but they may enlarge to several centimeters.
– Patients may develop multiple lesions within a single anatomic area, to the extent that the lesions collide and produce confluent actinic keratosis over a relatively large area. Variants may be brown ( pigmented actinic keratosis), atrophic, bowenoid, lichen planus–like, or have exaggerated hyperkeratosis, producing a hornlike projection above the skin surface known as a cutaneous horn. |
Work upLaboratory Studies
- – Are not needed unless the sudden appearance of multiple pruritic seborrheic keratoses occurs(Leser-Trélat sign)
- Imaging Studies
- – are not needed, unless the sudden appearance Leser-Trélat sign
Procedures
- – The shave biopsy provides histologic material for accurate diagnosis and removes the lesion in a cosmetically acceptable manner at the same time Histologic Findings
– These lesions are raised above the skin surface and they show a papillomatous epithelial proliferation containing horn cysts without any tendency toward malignancy.
-The proliferating cells are epidermal and have a basaloid appearance. The number of epidermal basal cells is greatly increased. The acanthotic pattern is the most frequent, in which a thick layer of basal cells is observed interspersed with pseudo-horny cysts. Invaginations to form keratin-filled pseudocysts are present. Some of these cells contain melanin
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Work up
Laboratory Studies
-Blood work is not indicated
Procedures
-A Skin biopsy is indicated to confirm the diagnosis and to rule out invasive squamous cell carcinoma for suspicious or more advanced lesions. It is also indicated for recurrent lesions or those that are unresponsive to therapy.
Fluorescence with the use of a photosensitizing drug (methyl ester of 5-aminolevulinic acid [ALA], a precursor of protoporphyrin) commonly used duringphotodynamic therapy (PDT) has been described as a diagnostic for actinic keratosis. Areas of involvement, including occult areas of abnormal skin, emit a pink fluorescence with a Wood lamp or photodynamic therapy lamp.
Histologic Findings
– dysplasia and architectural disorder of the epidermis
-Keratinocytes of the basal layer are abnormal and are variable in size and shape
– cellular polarity is altered, and nuclear atypia is seen.
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| Treatment:Medical Care-Ammonium lactate and alpha hydroxyl acids
-trichloroacetic acid
Topical treatment
-Tazarotene cream 0.1%
Surgical Care
1. cryotherapy with carbon dioxide (dry ice) or liquid nitrogen
2 Electrodesiccation
3. electrodesiccation and curettage
4. curettage alone
5. shave biopsy or excision
– provides histologic material for accurate diagnosis and removes the lesion in a cosmetically acceptable manner at the same time
6. dermabrasion surgery |
Treatment:
Medical Care
-1. Topical 5-fluorouracil (5-FU)
– inhibit thymidylate synthetase and cause cell death in actively proliferating cells
– BID x 1 month
2. 5% and 3.75% imiquimod cream
– Up-regulates a variety of cytokines, which, in turn, invoke a nonspecific immune response (interferons, natural killer cells) and a specific immune response (T cells)
-BID x 4 months
3. topical diclofenac gel
– nonsteroidal anti-inflammatory drug.Its mechanism of action against actinic keratoses is unknown.
– BID x 3 months
4. PDT with topical delta-aminolevulinic acid
-uses a light-sensitizing compound that preferentially accumulates in actinic keratosis cells
– Delta-aminolevulinic acid is a component of the heme biosynthetic pathway that accumulates preferentially in dysplastic cells. Once inside these cells, it is enzymatically converted to protoporphyrin IX, a potent photosensitizer. With exposure to light of an appropriate wavelength, oxygen free radicals are generated and cell death results
Surgical Care
1.Cryosurgery refers to use of a cryogen to lower the temperature of the skin and produce cell death.
2. curettage, shave excision, or conventional excision
3. Cosmetic resurfacing procedures
-medium and deep chemical peels
-dermabrasion
-and ablative laser resurfacing. |
References:
Harrison’s Principles of Internal Medicine, 18th edition
http://emedicine.medscape.com 01/11/14
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Pictures of Seborrheic Kerotosis on the Back
(ROJ)
Specimen split into half (longitudinally)
Skin lesion separated from dermis
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January 12, 2014
Below is a link on shave excision.
http://youtu.be/gSDl3OkkeMk
Problem-based Learning in Surgery 