A significant lifetime ultraviolet radiation exposure is the principal determinant of squamous cell carcinoma (SCC) and the disease appears most frequently in the older, fair-skinned population [1]. Increased use of natural or artificial sunlight by the younger generation may be one of the reasons for the rising incidence of cutaneous squamous cell carcinoma (cSCC) [2] [3]. Chronic skin ulceration and an immunosuppressed state are also predisposing factors for this malignant disease.

The carcinoma appears most commonly on sun-exposed areas, mainly on the head and neck. Changes are often present on the forehead, scalp, lip, and ears. The presentation is variable and the tumor could arise in the form of a plaque, nodule, or non-healing ulcer with scaling and crusting. The size is an important indicator for the risk of metastasis, as is the rate of growth and the state of differentiation of the cells. Growths larger than 2 cm metastasize more frequently than smaller ones [4] [5]. Another factor influencing the rate of metastases is the location with the lips and ears among the most dangerous areas.

There are several forms of cSCC, which may range from in situ neoplasm to metastatic disease. Cutaneous SCC often develops from actinic keratoses which are very common, scaly and small precancerous lesions found on sun-exposed areas [6]. Different studies report varying rates for actinic keratoses turning into invasive cSCC, while about a quarter of them will regress within a year [7]. Actinic cheilitis, another precancerous lesion, appears on a lip as a fissure or dry patch, and sometimes develops into SCC. Squamous cell carcinoma in situ, in some cases called Bowen disease, is a precursor of fully developed cSCC. Invasive cSCC could spread locally and metastasize [4]. The variant of SCC, Marjolin ulcer, can develop at the sites of chronic inflammation and has an over 30% metastasis and mortality rate [8] [9] [10].

Conjunctival squamous cell carcinoma has a variable appearance. An unusual pterygium may indicate the presence of a tumor, hence all resected pterygia should undergo histologic examination [11].

• Fatigue

  Squamous cell anal cancer: Find the most comprehensive real-world symptom and treatment data on squamous cell anal cancer at PatientsLikeMe. 65 patients with squamous cell anal cancer experience fatigue, depressed mood, pain, anxious mood, and insomnia [attack.icu]

  (b) Number of adverse events by the end of treatment The most frequently encountered adverse effects associated with the combined adjuvant therapy regimen were dry skin, fatigue, and generalised eye and lip reactions ( Brewster 2007 ). [doi.org]

  In both cohorts, the median duration of response was 7.6 months.[ 50 ][ Level of evidence: 3iiiDiv ] The most common adverse events were muscle spasms, alopecia, dysgeusia, weight loss, and fatigue. [cancer.gov]

  The most frequently reported adverse reactions ( 30%) include edema, nausea, vomiting, muscle cramps, musculoskeletal pain, diarrhea, rash, fatigue and abdominal pain. [cancerindex.org]

• Long Arm

  The latter was conspicuous in unbanded orcein-stained preparations owing to the presence of a virtually nonstaining region on its long arm. These findings are of interest in the light of the paucity of data on this type of tumour. [ncbi.nlm.nih.gov]

• Otalgia

  Additionally, local symptoms such as dysphagia or otalgia (for a progressive squamous cell carcinoma on the face) are prominent. In the United States an estimated 3932 to 8791 patients died from invasive cutaneous squamous cell carcinoma in 2012. [dermatologyadvisor.com]

• Ulcer

  The primary tumor of both patients showed complete regression, leaving ulceration. In patient 1, the ulceration completely resolved after 3 months. Patient 2 underwent surgical resection and full-thickness skin grafting. [ncbi.nlm.nih.gov]

  Presentation SCC usually presents as an indurated nodular keratinising or crusted tumour that may ulcerate, or it may present as an ulcer without evidence of keratinisation [ 1 ]. [patient.info]

• Fair Complexion

  Causes Those at greatest risk are: Those who have fair complexions and poor tanning capacity (burn easily Over 55 years of age Male (two to three times more common in men than in women) Have worked outdoors most of their lives Have been exposed to chemical [healthcentral.com]

  Fair complexion Persons with a fair complexion; hazel, blue, or gray eyes; and light-colored hair (blond or red), as well as those who burn easily when exposed to the sun, are at higher risk for cSCC than are persons with other physical characteristics [emedicine.medscape.com]

  complexion, 3 blue eyes, 11 male sex, 11,12 and older age at transplant. [skintherapyletter.com]

  Middle-aged and elderly persons, especially those with fair complexions and frequent sun exposure, are most likely to be affected. If treated in a timely manner, it is uncommon for squamous cell carcinoma to spread to other areas of the body. [tcdermatology.com]

• Blonde Hair

  People at the highest risk for developing basal cell carcinoma have fair skin, red or blond hair, and green, blue, or gray eyes. [nyulangone.org]

  Individuals with light-colored skin, freckled skin, blond hair, red hair, and light eyes have a greater risk for skin cancer. [innerbody.com]

  Red or blond hair. Although having a fair complexion is a risk factor for skin cancer and actinic keratosis, people of all skin colors can get skin cancer and actinic keratosis. [web.archive.org]

  Certain things can increase your chances of developing melanoma, such as having: lots of moles or freckles pale skin that burns easily red or blonde hair a close family member who's had melanoma Related topic Read more about the causes of melanoma Diagnosing [www2.hse.ie]

• Skin Plaque

  Slow-growing ulcer or reddish skin plaque. Bleeding may occur from the tumour. SCC may give rise to local metastases or spread to local lymph nodes [ 1 ]. [patient.info]

  The lesion caused by SCC is often asymptomatic Ulcer or reddish skin plaque that is slow growing Intermittent bleeding from the tumor, especially on the lip The clinical appearance is highly variable Usually the tumor presents as an ulcerated lesion with [en.wikipedia.org]

• Mechanically Fragile Skin

  People with the inherited condition recessive dystrophic epidermolysis bullosa (RDEB), in which there is a defect in the type VII collagen gene whereby either no collagen VII or very low levels are produced resulting in a mechanically fragile skin, have [doi.org]

A careful description of the appearance, location, and size of the tumor is essential. The gold standard for diagnosis is the histological evaluation. This method efficiently distinguishes cSCC from other skin conditions [12]. Nevertheless, problems do arise, especially when the bioptic sample is too small [13]. The biopsy must contain the full thickness of the diseased tissue, as well as adjacent normal skin for comparison. Excisional biopsy may be well suited for small lesions, but for larger lesions and those in esthetically and functionally important areas, incisional biopsy is performed as a base for a decision of definitive treatment.

Actinic keratosis contains atypical keratinocytes. It is classified according to the distribution of the atypical cells. In the first category (KIN I), the dysplastic keratinocytes are restricted to the lower third of the epidermis, whereas in higher categories they occupy an increasing thickness. In the KIN III category – which is the same as cSCC in situ - the atypical keratinocytes occupy all layers of the epidermis [14].

The classification of cSCC is according to the tumor-node-metastasis (TNM) staging system. This scheme incorporates the size of the tumor, the involvement of regional lymph nodes, and the absence or presence of metastases. An alternative scheme for nodal staging has been developed recently with good predictive power [15].

New methods for a noninvasive examination of skin lesions (dermoscopy, reflectance confocal microscopy, optical coherence tomography) have been developed [16]. Computerized tomography (CT) and magnetic resonance imaging (MRI) are used to examine the extent of the disease.

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