What are the other Names for this Condition? (Also known as/Synonyms)

• Epidermotropic Eccrine Carcinoma of Skin
• Malignant Intraepidermal Eccrine Poroma
• Poroepitheleoma of Skin

What is Porocarcinoma of Skin? (Definition/Background Information)

• Porocarcinoma of Skin is a rare malignant tumor that originates from the eccrine or apocrine sweat glands. The tumor normally occurs on the lower limbs and head and neck region
• There are three different types of sweat glands in the skin. These include the following:
  • Apocrine sweat glands
  • Eccrine sweat glands
  • Apoeccrine sweat glands
• Porocarcinoma of Skin is usually observed in older adults. It is a slow-growing tumor that can metastasize; metastasis is observed in about 20% of the cases
• The cause of Porocarcinoma of Skin is unknown, but it can be found in association with a benign poroma, implying a malignant degeneration of a prior benign lesion
• The treatment of choice is a surgical excision with clear margins followed by radiation therapy or chemotherapy, as decided by the healthcare provider
• In majority of the cases, the prognosis is good with appropriate early treatment. However, the prognosis of Porocarcinoma of Skin also depends upon the stage of the tumor, health status of the individual, and if it has metastasized

Who gets Porocarcinoma of Skin? (Age and Sex Distribution)

• Porocarcinoma of Skin is a rare condition that is more common in elderly adults - average age 65 years
• Both males and females are equally affected
• All racial and ethnic groups may be affected

What are the Risk Factors for Porocarcinoma of Skin? (Predisposing Factors)

• The risk factor for Porocarcinoma of Skin includes the presence of poromas
• Eccrine poromas can rarely occur within nevus sebaceous
• Currently, no other risk factors have been established

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Porocarcinoma of Skin? (Etiology)

• The cause of development of Porocarcinoma of Skin is presently unknown. However, some researchers believe that it arises from the eccrine sweat gland
• It can arise spontaneously or from benign eccrine poroma (skin tumor), which turns malignant
• Genetic mutations have been suspected by researchers in some cases, but these have not been well-characterized

What are the Signs and Symptoms of Porocarcinoma of Skin?

Porocarcinoma of Skin may present the following signs and symptoms:

• Porocarcinoma of Skin is typically seen as a solitary nodule
• It is mostly asymptomatic and painless
• The nodule may ulcerate, which can cause pain at the site
• It is a slow-growing malignant tumor
• In 50% of the cases, the tumor occurs in the lower limbs (including the buttocks, legs, and feet); about 25% occur in the head and neck region
• Porocarcinoma of Skin can present like basal cell carcinoma or squamous cell carcinoma (both malignant skin tumors), hence it is often biopsied
• If porocarcinoma has metastasized, regional lymph nodes may be palpable

How is Porocarcinoma of Skin Diagnosed?

A diagnosis of Porocarcinoma of Skin may involve the following:

• A thorough medical history and physical examination
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Porocarcinoma of Skin?

Porocarcinoma of Skin can cause the following complications:

• The tumor can metastasize to the local lymph nodes and to distant organs too; nearly 1 in 5 tumors are known to metastasize
• Ulceration of the tumor can lead to secondary infections of bacteria and fungus
• Some individuals may have concerns regarding their cosmetic appearance
• Recurrence of the tumor after a period of time on incomplete removal; the recurrence rate after excision is approximately 20%
• Side effects of chemotherapy (such as toxicity) and radiation therapy

How is Porocarcinoma of Skin Treated?

The treatment of Porocarcinoma of Skin may involve the following:

• In most cases, a wide surgical excision and removal of the entire tumor is the preferred treatment option. This may be followed by radiation therapy and/or chemotherapy
• Wide and complete excision using Mohs Micrographic Surgery is optimal, particularly since metastatic disease is poorly responsive to chemotherapy and radiation
• If the tumor has metastasized, then a combination of chemotherapy, radiation therapy, and invasive procedures may be used to treat the tumor
• Follow-up care with regular screening and check-ups are important and encouraged

How can Porocarcinoma of Skin be Prevented?

• Currently, there are no known methods to prevent Porocarcinoma of Skin occurrence
• Regular medical screening at periodic intervals with blood tests, scans, and physical examinations are mandatory due to its metastasizing potential and possibility of recurrence. Often several years of active vigilance is necessary

What is the Prognosis of Porocarcinoma of Skin? (Outcomes/Resolutions)

• Porocarcinoma of Skin is a malignant tumor and its prognosis depends upon a set of several factors, which include:
  • Stage of tumor: With lower-stage tumors, when the tumor is confined to site of origin, the prognosis is usually excellent with appropriate therapy. In higher-stage tumors, such as tumors with metastasis, the prognosis is poor
  • The surgical resectability of the tumor (meaning if the tumor can be removed completely) 
  • Overall health of the individual: Individuals with overall excellent health have better prognosis compared to those with poor health
  • Age of the individual: Older individuals generally have poorer prognosis than younger individuals
  • Whether the tumor is occurring for the first time or is a recurrent tumor. Recurrent tumors have a poorer prognosis compared to tumors that do not recur 
  • Response to treatment: Tumors that respond to treatment have better prognosis compared to tumors that do not respond so well to treatment
• An early diagnosis and prompt treatment of the tumor generally yields better outcomes than a late diagnosis and delayed treatment
• If metastasis, such as to the local lymph nodes, is observed, then the prognosis is unpredictable
• Regular follow up visits with the healthcare provider are important

Additional and Relevant Useful Information for Porocarcinoma of Skin:

• There is no evidence to prove that Cutaneous Porocarcinoma formation is influenced by one’s dietary choices
• Cleaning the skin too hard with strong chemicals or soaps may aggravate the skin condition. Care must be taken avoid strong soaps and chemicals that could potentially worsen the condition
• The presence of dirt on the body is not a causative factor for the condition. However, it helps to be clean and hygienic, which may help the condition from getting worse