21- Skin & Hand Explains Flashcards
What is seborrhoeic keratosis?
Seborrhoeic keratosis is a benign skin condition that commonly occurs in patients over the age of 50. It is often idiopathic and equally affects both sexes. Multiple lesions are typically present on the face and trunk, and there are different subtypes characterized by flat, raised, filiform, or pedunculated appearances. The lesions can have variable colors and may have greasy scales on the surface. Treatment options include leaving them alone or performing a simple shave excision.
What are melanocytic naevi?
Melanocytic naevi, also known as moles, are benign skin growths. There are different types of melanocytic naevi, including congenital melanocytic naevi, junctional melanocytic naevi, compound naevi, Spitz naevus, and atypical naevus syndrome. Congenital melanocytic naevi are usually present at birth or soon after and tend to be larger than 1cm in diameter. They have an increased risk of malignant transformation. Junctional melanocytic naevi are circular macules with variable coloration. Compound naevi are domed pigmented nodules that arise from junctional naevi and have uniform color and a smooth appearance. Spitz naevus usually develops in children over a few months, can be pink or red, and commonly occurs on the face and legs. Atypical naevus syndrome refers to individuals with atypical melanocytic naevi that may be inherited and have an increased risk of developing melanoma, especially if there is a family history of melanoma.
What are epidermoid cysts?
Epidermoid cysts are common benign skin cysts that can affect the face and trunk. They have a central punctum and may contain small quantities of sebum. The cyst lining is either normal epidermis, resulting in an epidermoid cyst, or the outer root sheath of a hair follicle, causing a pilar cyst.
What is dermatofibroma?
Dermatofibroma is a solitary dermal nodule that typically affects the extremities of young adults. The lesions feel larger than they appear visually. Histologically, they consist of proliferating fibroblasts merging with sparsely cellular dermal tissues.
What are the different types of skin malignancies?
Skin malignancies include basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
What are some examples of painful skin lesions?
Some examples of painful skin lesions include eccrine spiradenoma, neuroma, glomus tumor, leiomyoma, angiolipoma, neurofibroma (rarely painful), and dermatofibroma (rarely painful). These conditions can cause pain due to various factors such as nerve involvement or compression.
What is squamous cell carcinoma?
Squamous cell carcinoma is another type of skin cancer that is related to sun exposure. It may arise in pre-existing solar keratoses. If left untreated, it can metastasize. The risk of squamous cell carcinoma is increased in individuals who are immunosuppressed, such as following a transplant. Wide local excision is the treatment of choice, and repeat surgery may be required to ensure adequate margins if a diagnostic excision biopsy has shown squamous cell carcinoma.
What is basal cell carcinoma?
Basal cell carcinoma is the most common form of skin cancer. It commonly occurs on sun-exposed sites, except for the ear. There are different subtypes, including nodular, morphoeic, superficial, and pigmented. Basal cell carcinomas are typically slow-growing with low metastatic potential. Treatment options include standard surgical excision, topical chemotherapy, and radiotherapy. A diagnostic punch biopsy should be taken at a minimum if treatment other than standard surgical excision is planned.
What are the main diagnostic features of malignant melanoma?
The main diagnostic features of malignant melanoma include a change in size, a change in shape, and a change in color.
What are the secondary features of malignant melanoma?
The secondary features of malignant melanoma include a diameter larger than 6mm, inflammation, oozing or bleeding, and altered sensation. These features, along with the major diagnostic criteria, can help in the evaluation of melanoma.
What is the recommended approach for suspicious lesions?
Suspicious lesions should undergo excision biopsy for further evaluation. It is important to remove the lesion completely as incision biopsy can make subsequent histopathological assessment difficult.
How are the margins of excision determined for different thicknesses of lesions?
The margins of excision for different thicknesses of lesions are as follows:<br></br>Lesions 0-1mm thick: 1cm<br></br>Lesions 1-2mm thick: 1-2cm (depending upon site and pathological features)<br></br>Lesions 2-4mm thick: 2-3cm (depending upon site and pathological features)<br></br>Lesions >4mm thick: 3cm
What are some further treatments that may be applied for certain cases?
Further treatments such as sentinel lymph node mapping, isolated limb perfusion, and block dissection of regional lymph node groups should be selectively applied. These treatments are considered based on the specific case and its characteristics.
What is Kaposi Sarcoma?
Kaposi Sarcoma is a tumor that affects the vascular and lymphatic endothelium. It is characterized by purple cutaneous nodules. It is associated with immunosuppression. The classical form of Kaposi Sarcoma affects elderly males and is slow-growing. The immunosuppression form is more aggressive and tends to affect individuals with HIV-related disease.
What is dermatofibroma?
Dermatofibroma is a benign lesion characterized by firm elevated nodules. It is usually associated with a history of trauma. The lesion consists of histiocytes, blood vessels, and fibrotic changes.
What is dermatitis herpetiformis?
Dermatitis herpetiformis is a non-malignant skin disease characterized by chronic itchy clusters of blisters. It is linked to underlying gluten enteropathy, also known as coeliac disease.
What is pyogenic granuloma?
Pyogenic granuloma is an overgrowth of blood vessels that appears as red nodules. It typically develops following trauma and can sometimes resemble amelanotic melanoma.
What are the characteristics of acanthosis nigricans?
Acanthosis nigricans is characterized by brown to black, poorly defined, velvety hyperpigmentation of the skin. It is commonly found in body folds such as the posterior and lateral folds of the neck, the axilla, groin, umbilicus, forehead, and other areas. The most common cause of acanthosis nigricans is insulin resistance, which leads to increased circulating insulin levels. In the context of a malignant disease, acanthosis nigricans is referred to as acanthosis nigricans maligna and is considered a paraneoplastic syndrome. Rare involvement of mucous membranes suggests a coexisting malignant condition.
When is a tru-cut biopsy most often used?
A tru-cut biopsy is most often used for percutaneous sampling of deep-seated lesions or used intraoperatively for visceral lesions.
What is the main objective of wide excision?
The main objective of wide excision is to completely remove the lesion with healthy margins. In cosmetically sensitive sites or when the defect is large, plastic surgical techniques may need to be complemented with the excision.
In what cases is a 5mm punch biopsy used?
A 5mm punch biopsy is used for diagnostic confirmation of lesions suspected to be benign or when the definitive management is unlikely to be surgical. It may not be as useful for pigmented lesions as it may not provide sufficient tissue for accurate diagnosis. It can be used in non-melanoma type skin diseases to establish a diagnosis before more extensive resection.
When is an incisional biopsy used?
An incisional biopsy is mainly used for deep-seated or extensive lesions where there is diagnostic doubt, usually following a core or tru-cut biopsy. It is rarely used for skin lesions.
What is the purpose of a diagnostic excision?
A diagnostic excision is primarily used for lesions that are suspicious for melanoma. The lesion is excised with a rim of normal tissue, and subsequent excision of margins may be required.
What are sebaceous cysts?
Sebaceous cysts originate from sebaceous glands and contain sebum, a oily substance. They can develop anywhere on the body, but are most commonly found on the scalp, ears, back, face, and upper arms (excluding the palms of the hands and soles of the feet).
What is a characteristic feature of sebaceous cysts?
Sebaceous cysts typically have a punctum, which is a small opening on the skin’s surface.
What is the recommended treatment for sebaceous cysts?
To prevent recurrence, it is necessary to completely excise the cyst wall during removal. This ensures that the entire cyst is removed.
What is a Cock’s ‘Peculiar’ Tumour?
A Cock’s ‘Peculiar’ Tumour is a specific type of sebaceous cyst. It is characterized by suppuration (formation of pus) and ulceration. This type of cyst may resemble a squamous cell carcinoma, which is why it is given its name.
