Unlike basal cell, invasive squamous cell carcinoma is a more common finding. Squamous carcinomas are a common type of cancer that occur on the skin, esophagus, cervix, vagina, anus, lung, prostate, mouth, throat and lips. Initially squamous cell carcinomas are localized and cure is possible by removing the tumor.
Risk factors for squamous cell cancer of the skin include older males, light blonde skin or blue eyes, skin that sunburns easily, living in a hot environment, constant exposure to UV light or chemicals (arsenic), and a prior history of skin cancer. In general squamous cell cancer occurs in people who smoke and drink alcohol. On the skin the biggest risk factor for squamous cell cancer is prolonged exposure to sunlight. In some individuals who have a chronic non healing ulcer, one can develop a squamous cell cancer. Unlike a basal cell cancer, squamous carcinomas have a great risk of spread.
Symptoms of a squamous cancer depend on the organ affected and growth rate. On the skin squamous cell cancer has no symptoms. One may note a reddish or grey lesion on the forehead, neck or upper arms. Often the lesion may show changes like ulceration, scaling, crusting or itching.
Squamous cell cancer often occurs on the lower lip and may cause intermittent bleeding. On the mouth, tongue or throat, squamous cell cancer may present as a lump and may cause pain, difficulty swallowing, coughing or abnormal taste.
In most cases, squamous cell cancers are slowly growing lesions. At this stage this cancer can be cured. However, if the lesions are ignored the end result is an invasive squamous cell cancer. Squamous cell cancer can invade nearby tissues and locally spread making cure difficult. With time these invasive cancers also start to spread elsewhere in the body and are known as metastatic cancers. Localized squamous cell cancers are treated by surgery, laser or desiccation and curettage. On the skin, invasive squamous cancers should be removed with the help of a plastic surgeon as reconstruction is almost always required.
All patients with metastatic squamous cell carcinoma invasive should be assessed for spread to the local lymph nodes. Once the cancer has spread, it is futile to perform surgery and the patient may require chemotherapy and or radiation.
Metastatic squamous cell carcinoma invasive can occur if treatment is delayed. Anytime lymph nodes are involved, the prognosis of the cancer is worse. In most studies when metastatic disease has occurred, survival at 5 years averages about 40-70 percent. However, if squamous cell cancer has spread to the lung, the disease is not curable.
Low risk squamous cell cancer can be cured with surgical therapy but at least 40% develop recurrence within 2 years. Therefore, all patients who have been diagnosed with invasive squamous cell carcinoma must follow up with their doctor.