Squamous cell carcinoma : SCC

Skin cancer ---> Non melanoma skin cancer ---> squamous cell carcinoma

Squamous cell carcinoma is a malignant invasive proliferation of epidermal keratinocytes.
Epidemiology
Squamous cell carcinoma is the second most common type of skin cancer. It is more common in men and in the elderly population.
Pathology
There is a relationship with chronic ultraviolet exposure. Squamous cell carcinoma is especially common in individuals with skin phototypes I and II. Other etiological factors include topical and systemic carcinogens such as arsenic, photochemotherapy (PUVA) and chronic immunosuppression (following allogeneic organ transplantation or in those with lymphoma or leukemia). The lesions may also arise at sites of long-standing radiation dermatitis, scarring (discoid lupus erythematosus), ulceration and pre-existing lesions such as Bowen's disease. Some squamous cell carcinomas are associated with human papillomavirus infection. Smoking is associated with lesions on the lip.
Scope of disease
Squamous cell carcinoma is locally invasive and has the potential to metastasize to lymph nodes and other organs of the body.
Clinical features
Squamous cell carcinoma usually presents as an expanding plaque or nodule with an ill-defined, indurated base and surface crusting. The lesion may ulcerate. It is most often seen on sun-exposed sites (face, neck, forearms and dorsum of hands) in association with solar elastosis and multiple actinic keratoses. Local lymph nodes may be enlarged with metastatic involvement.
Investigations
Skin biopsy
A skin biopsy is required to establish a histopathological diagnosis and to gain information on the degree of differentiation, grade, depth and level of dermal invasion, the presence of perineural, vascular or lymphatic invasion, and clearance margins of the excised tissue.
Lymph node biopsies
Squamous cell carcinomas usually spread to local lymph nodes; therefore clinically enlarged nodes should be excised and submitted for histopathological analysis.
Initial management
Patient education
Sun avoidance, the use of sunscreen and protective clothing are the main steps in the prevention of actinic keratosis and further squamous cell carcinomas, particularly in patients receiving immunosuppression.
Multidisciplinary team approach
There is overlap between dermatologists, clinical oncologists and plastic surgeons in the management of patients with squamous cell carcinoma, and therefore a multidisciplinary approach is favored.
Surgical management
Curettage and cautery
Curettage and cautery may be feasible treatment options for small, well-defined, low-risk tumors.
Excision biopsy and regional node dissection
Surgical excision or Mohs' micrographic surgery is the treatment of choice for the majority of lesions. For low-risk tumors (less than 2 cm in diameter), excision with a 4 mm margin is expected to achieve complete cure in 95%.
Mohs' micrographic surgery is indicated for larger, higher-risk tumors. With this technique, each section is examined with frozen section analysis to determine the completeness of resection. It is particularly useful in difficult sites where wide surgical margins may be technically difficult to achieve without functional impairment.
Tumor-positive lymph nodes are usually managed by regional node dissection.
Medical management
Radiotherapy
Other treatment options include radiotherapy for non-resectable tumors or lymph node disease.
Prognosis
Squamous cell carcinoma has an overall remission rate after therapy of 90%. The factors that influence metastatic potential include anatomical site, tumor size, degree of differentiation and immunosuppression. Tumors arising in areas of radiation injury, chronic inflammation or chronic ulcers have the highest metastatic potential when compared to those from sun-exposed sites. Tumors more than 2 cm in diameter are 3 times as likely to metastasize compared to smaller tumors. Tumors more than 4 mm in depth or extending down to the subcutaneous tissue are more likely to recur and metastasize compared to thinner tumors. Poorer prognosis is associated with less well differentiated tumors, and tumors arising in patients who are immunosuppressed.

Squamous Cell Carcinoma pictures

skin cancer pictures ---> squamous cell carcinoma ---> squamous cell carcinoma pictures

Squamous Cell Carcinoma: SCC

Skin cancer ---> Non melanoma skin cancer ---> squamous cell carcinoma

SCC is the second most common form of skin cancer and is derived from the epithelial keratinocyte. SCC can deeply invade surrounding structures and metastasizes most commonly to regional lymph nodes. In immunosuppressed transplant individuals, SCC is the most common skin cancer, occurring 65 to 250 times more frequently than in the general population. SCC in these individuals tends to have more aggressive behavior.
Several precursor lesions to invasive SCC exist, most commonly actinic keratosis and Bowen's disease (in situ SCC). Erythroplasia of Queyrat, another precursor lesion, represents SCC in situ on the glans penis. Histologically, SCC shows malignant degeneration of epithelial cells with differentiation toward keratin formation. SCC often appears clinically as a non healing sore with ulceration and inflammatory pink borders or an erythematous papulonodule with overlying keratotic crust or ulceration. These tumors most often arise in chronically actinically damaged skin or within an actinic keratosis, but they may also develop in burn scars or chronic inflammatory wounds. These lesions may infiltrate widely. Metastasis to regional lymph nodes accounts for approximately 80% to 90% of metastatic cases. Distant sites, such as lung, liver, brain, bone, and skin, account for the other 10% to 20%. Metastatic SCC portends a poor prognosis with a 10-year survival rate for regional lymph node disease of less than 20% and for distant disease of 10%.
Accurate assessment of the higher-risk cutaneous SCCs is handicapped because of the lack of large prospective studies using multivariate analysis. Nine variables, however, have been identified as prognostic risk factors by retrospective analysis.

Etiology of BCC and SCC

Surgical Treatment of Nonmelanoma Skin Cancers

Adjuvant and Primary Radiation Therapy for nonmelanoma cancers

Actinic keratosis: Skin Cancers and their precursors

Non melanoma skin cancer ---> squamous cell carcinoma ---> Early skin cancer ---> Actinic keratosis

Actinic keratosis (solar keratosis) are lesions that result from cumulative damage to keratinocytes by ultraviolet radiation. They are common lesions, particularly in individuals with skin phototypes I and II who are over the age of 40 and give a history of chronic sun exposure. On examination, they appear as multiple red, scaly plaques on sun-exposed skin. All patients should be strongly advised to minimize their sun exposure. Cryotherapy is effective in most cases; otherwise topical 5-fluorouracil cream or retinoids can be used. The presence of actinic keratosis is an indicator of increased risk of non-melanoma skin cancers. They occasionally disappear spontaneously but in general remain for many years.

Treating Actinic Keratoses

Skin cancer awareness ---> skin cancer videos ---> Squamous cell carcinoma ---> Actinic keratosis ---> treatment of Actinic keratosis

Because pre-cancerous lesions can become full-blown skin cancer, it's important to treat them immediately upon diagnosis.

Stage One of Skin Cancer: Actinic Keratosis (Skin Cancer #2)

Skin cancer awareness ---> skin cancer videos ---> Squamous cell carcinoma ---> Actinic keratosis

Pre-cancerous lesions called actinic keratoses, crop up on millions of Americans every year. Let's take a closer look at AKs.

Bowen's disease

Non melanoma skin cancer ---> squamous cell carcinoma ---> Early skin cancer ---> Bowen's disease

Bowen's disease (squamous cell carcinoma in situ) presents as a fixed red plaque and represents an intra epidermal squamous cell carcinoma.
Epidemiology
Bowen's disease may occur at any age but is rare before the age of 30; most patients are aged over 60 at presentation. In the UK, it occurs predominantly in women (85% of cases).
Pathology
A number of different factors have been implicated in the aetiology of Bowen's disease. The age group and body sites affected are suggestive of a relationship with chronic exposure to ultraviolet radiation.
Histologically, keratinocytes show loss of polarity, atypia and increased mitotic rate with involvement of the entire thickness of the epidermis from basal layer to stratum corneum. The basement membrane remains intact.
Clinical features
Bowen's disease presents as solitary or multiple, gradually enlarging, well-demarcated erythematous macules, papules or plaques. The lesions usually have an irregular border with surface crusting or scaling. Approximately 75% of lesions are on the lower legs. They are most often asymptomatic, but may bleed. In the uncircumcised male, the lesions can present as smooth, red, velvety plaques on the glans penis (erythroplasia of Queyrat).
Investigations
The diagnosis is suggested on the basis of clinical features.
Skin biopsy
Histology is required to confirm the diagnosis.
Management
Ablation of the lesion
Treatment options for Bowen's disease include cryotherapy, curettage and cautery, excision, laser (CO2, argon and Nd:YAG) and topical 5-fluorouracil (applied once or twice daily as 5% cream for up to 2 months). All have recurrence rates of up to 10% and no treatment modality appears to be superior.
Prognosis
If Bowen's disease is untreated, most studies suggest a 3% risk of progression to invasive squamous cell carcinoma. Up to 50% of patients have other previous or subsequent skin malignancies, most commonly basal cell carcinoma. Genital Bowen's disease carries a higher risk of invasive cancer.

Squamous Cell Carcnoma Higher Risk Factors

Non melanoma skin cancer ---> squamous cell carcinoma ---> metastatic risk

These include the following factors:
Recurrent tumor

Anatomic location
High risk: central face, eyelid, eyebrow, periorbital, nose, lip, chin, mandible, temple, ear, in front or behind the ear, genitalia, hand and foot
Medium risk: cheeks, forehead, scalp, and neck
Low risk: trunk, extremity (excluding hand/foot)

Size
Lesions +6 mm on high-risk area
Lesions +10 mm on medium-risk area
Lesions +20 mm on low-risk area

Histology
Poorly differentiated

Depth of invasion
Clark's level IV (lesion that involves the reticular dermis), V (lesion that invades into subcutaneous fat), or +4 mm

Perineural invasion

Rapid growth

Etiology
Scar, chronic ulcer or inflammatory process, sinus tract, sites of prior radiation therapy

Immunosupression

Understanding Squamous Cell Carcinoma (Skin Cancer #5)

Skin cancer awareness ---> skin cancer videos ---> Squamous cell carcinoma

Every year, 250,000 Americans are diagnosed with a form of skin cancer called squamous cell carcinoma. What exactly is SCC?

How to Identify Skin Cancer Signs : Signs of Squamous Cell Carcinoma Skin Cancer

Skin cancer awareness ---> skin cancer videos ---> Squamous cell carcinoma ---> Skin cancer detection

Learn how to identify the signs of squamous cell carcinoma skin cancer with expert tips from a doctor on skin health.

Understanding Squamous Cell Carcinoma (Skin Cancer #5)

Skin cancer awareness ---> skin cancer videos ---> squamous cell carcinoma

Every year, 250,000 Americans are diagnosed with a form of skin cancer called squamous cell carcinoma. What exactly is SCC?