The risk of metastasis in squamous cell carcinoma (SCC) is generally low (around 2-5%), but it increases significantly with specific high-risk features like large size (>2cm), deep invasion (>4-6mm), location (ear, lip, temple), poor differentiation, perineural invasion, and immunosuppression, with some aggressive cases showing much higher rates and requiring careful monitoring and potentially intense treatment.
Squamous cell carcinoma rarely metastasizes (spreads to other areas of the body), and when spreading does occur, it typically happens slowly. Indeed, most squamous cell carcinoma cases are diagnosed before the cancer has progressed beyond the upper layer of skin.
Squamous cell carcinoma is a rare form of skin cancer in dogs. Tumors are found more frequently in light- skinned, hairless, or sparsely haired portions of the skin. At-risk breeds include Dalmatians, Bull Terriers, and Beagles.
Metastatic squamous cell carcinoma is often referred to as a neck cancer because it tends to travel to the lymph nodes in the neck and around the collarbone. Because of this, signs of metastasis may include a painful or tender lump in the neck or a sore throat that doesn't improve or go away.
One of the first red flags of metastasized breast cancer is persistent pain or discomfort. This pain can manifest in various parts of the body, including the bones, back, or chest. It's essential to differentiate between normal aches and pains and those that are persistent and unexplained.
The most common sites where cancer spreads are bone, liver, and lung. The following list shows the most common sites of metastasis, not including the lymph nodes, for some common cancers: In metastasis, cancer cells break away from where they first formed and form new tumors in other parts of the body.
Signs of Cancer
Many doctors will order a PET or CT scan once a squamous cell carcinoma diagnosis has been reached to ensure the cancer has not spread to other parts of the body and is contained within the layers of the skin. Your doctor may also test your lymph nodes near the tumor site.
Location on the Body
Squamous cell carcinomas that develop on high-risk areas of the body tend to behave more aggressively. These areas include the ears, lips, nose, scalp, fingers, and genitals, as well as sites where the skin is already damaged by chronic inflammation, burns, or scars.
Treatment overview
In July 2021, the FDA expanded this approval to include SCC that is locally advanced and not curable by radiation or surgery. In 2024, the FDA approved cosibelimab-ipdl (UnloxcytTM) for adults with locally advanced or metastatic squamous cell carcinoma that is not curable with surgery or radiation.
The median survival time for dogs that have mandibular (lower jaw) SCC treated with surgery alone varies from 19-43 months, with a 1-year survival of 88-100%, a 2-year survival of 79%, and a 3-year survival of 58%.
Signs and symptoms of squamous cell skin cancer
They can also develop in scars or skin sores elsewhere. These cancers can appear as: Rough or scaly red (or darker) patches, which might crust or bleed. Raised growths or lumps, sometimes with a lower area in the center.
Certain breeds are known to have an increased incidence of SCC, including American Pit Bull Terrier, Basset Hound, Beagle, Bloodhound, Boxer, Bull Terrier, German Shorthaired Pointer, Golden Retriever, Labrador Retriever, Norwegian Elkhound, and Standard Poodle.
Chemotherapy. Chemotherapy uses strong medicines to kill cancer cells. If squamous cell carcinoma spreads to the lymph nodes or other parts of the body, chemotherapy can be used alone or with other treatments, such as targeted therapy and radiation therapy. Targeted therapy.
One of the factors that can affect a patient's prognosis is whether the malignancy has metastasized (spread to another area of the body). Once squamous cell carcinoma has spread beyond the skin, the five-year survival rate drops to less than 50 percent.
Most squamous cell carcinomas of the skin are caused by too much ultraviolet (UV) radiation. UV radiation comes either from sunlight or from tanning beds or lamps.
A high-risk SCC is considered when the diameter of the tumor is larger than 2 cm as tumors of this size double the risk of SCC recurrence and triple the rate of metastasis compared to the smaller lesion. Therefore, a larger margin for excision is required on the high-risk SCC.
High-risk human papillomavirus (HR HPV) is associated with oropharyngeal squamous cell carcinoma (OPSCC), which is rising.
Squamous cell carcinoma is considered more serious than basal cell carcinoma due to its higher propensity to spread. While it typically doesn't metastasize as quickly as some other types of cancer, if left untreated, it can invade surrounding tissues, leading to more severe consequences.
Treatment should happen as soon as possible after diagnosis, since more advanced SCCs of the skin are more difficult to treat and can become dangerous, spreading to local lymph nodes, distant tissues and organs.
FDG-PET/CT can identify primary and locoregional disease in cSCC patients with high sensitivity, including small cutaneous and clinically impalpable nodal lesions, and thus has a potential role in initial staging and modifying subsequent treatment strategy.
Most basal cell and squamous cell skin cancers are caused by repeated and unprotected skin exposure to ultraviolet (UV) rays from sunlight, as well as from man-made sources such as tanning beds. UV rays can damage the DNA inside skin cells and cause changes in genes.
When cancer is suspected there is a fast route within the NHS to get further tests and specialist advice to rule out cancer. These are called 2 week wait referrals and you should be seen within 2 weeks of being referred.
About 90% of cancers are caused by environmental and lifestyle factors, not genetics, including smoking, poor diet (red meat, fried foods), alcohol, sun exposure, pollutants, infections, obesity, and inactivity; only 5–10% are due to inherited genetic defects, with most cancers arising from lifestyle-induced genetic mutations. Tobacco alone accounts for about a third of cancer deaths, while diet, obesity, and inactivity contribute significantly, with controllable factors being key to prevention.
Some general signs and symptoms associated with, but not specific to, cancer, include: Fatigue. Lump or area of thickening that can be felt under the skin. Weight changes, including unintended loss or gain.