Benign Skin Tumors: How Do They Appear?

When small tumors appear on our skin, it often worries us. However, in most cases, they're benign and don't cause any complications. Learn more in this article.
Benign Skin Tumors: How Do They Appear?

Last update: 09 October, 2021

Even just hearing “benign skin tumors” can cause concern, even though they aren’t harmful.

The skin, along with its constituent tissues, is an area where tumors appear most frequently. They’re evident through dermatological physical examination. Fortunately, most of them are benign tumors that don’t cause problems beyond the aesthetic aspect!

They can have different origins; from the epidermis, an attachment of the skin or the dermal and subcutaneous connective tissue, to some of the structures in the dermis, including nerves and blood vessels.

What are benign skin tumors?

The word “tumor” makes us think of something bad, but this isn’t always true. A tumor is a mass of tissue that grows autonomously, unrelated to the stimuli that control normal tissue growth.

They’re so common that it would be very strange to find someone who hasn’t presented one or more at some point. This doesn’t mean that we should ignore warning signs. For example, if you have a mole that has changed or is bleeding, you should go to a specialist. There’s no age or gender exempt from the dangers of skin tumors.

They’re usually congenital, but manifest and appear at any point in our lives. Only rarely, and over time, can they progress to malignant lesions. For this reason, early diagnosis and evolutionary control are crucial.

The following are the most common types of benign skin tumors.

Seborrheic keratosis

It’s the most frequent type of benign skin tumor. They appear, in people over 40 years of age, on the head, neck, and trunk. They’re similar to warts, raised, well delimited, yellowish or brownish, and with an oily or hyperkeratotic surface.

They can be between 0.2 and 7 inches (0.5 and 2 cm) in size and appear to be attached to the skin. However, you don’t have to get them treated. In case of irritation or if the patient feels discomfort for aesthetic reasons, treatment is based on curettage and electrocoagulation, cryotherapy, or biopsy.

Seborrheic keratosis
Seborrheic keratosis is more common in people over 40 years of age. They usually don’t require any treatment.

Acrochordons or soft fibroids

These are benign skin formations. Specialists estimate that 50% of the population presents this type of lesion, and the risk increases with age. The causes may be genetic predisposition and hormonal factors (especially in women, as they tend to multiply during pregnancy).

They occur frequently in people with obesity and diabetes; for this reason, they have been described as a sign of insulin resistance. They appear in areas where our clothing tends to rub, such as the neck, armpits, and groin. They usually receive cosmetical treatment and options include cryotherapy, shaving, or electrodesiccation.

Ruby nevi or ruby angiomas

These are red spots that appear throughout life in regions such as the abdomen, neck, and face. They’re also described as a group of dilated blood vessels on the surface of the skin, which don’t pose any risk to the patient’s health.

They affect about 75% of the population over 60 years of age. The number and size usually increase with age. However, they’re more common in diabetic patients and may increase if the individual is exposed to high temperatures.

On the other hand, some may bleed when they’re traumatized, but it’s very light bleeding and it doesn’t put the person at any risk.

Actinic keratosis

This is one of the frequent reasons for consultation both in primary care and in specialist care; 6% of patients who go for a check-up have this. The incidence is increasing, especially in old age and in people who have spent most of their lives in the sun.

It’s more evident by touch than by sight. It’s a scaly, crusty growth that evolves slowly and progressively. It may cause burning or itching and is red or brown.

Actinic keratosis on a nose
Actinic keratosis has become a common cause of dermatology consultations.

Dermatofibromas

They’re small reddish or brown bumps of firm consistency, caused by the accumulation of fibroblasts. Occasionally, they cause itching and they’re usually on the legs. When they cause pain or itching, they’re surgically removed.

Dermoid cyst

Made up of hair, sebaceous glands, and sweat glands. Some inner ones may contain cartilage, teeth, and bone fragments. In addition, and for cosmetic reasons, a professional can remove them via a surgical procedure.

General characteristics of benign skin tumors

  • They have slow and limited growth. They don’t cause infiltration or destruction in the surrounding tissue.
  • The cells that form them are uniform in appearance and size and don’t cause metastasis.
  • The prevalence of benign skin tumors increases considerably with age, in response to the functional and structural changes of keratinocytes due to biological aging. It also increases as a consequence of the harmful action of ultraviolet rays that provoke free radicals.

Skin self-examination

In conclusion, controlling skin lesions periodically is a recommended practice to prevent future issues. Finding new bumps, moles, or spots, seeing changes in existing ones, irregular borders, and bleeding may be warning signs to visit a specialist.

There’s an ABCDE rule for early detection of skin lesions:

  • Asymmetry
  • Border (irregular edges)
  • Color (variable and irregular color: red, blue, and black)
  • Diameter more than 0.3 inches (0.7 cm) wide
  • Evolving

The great variety of benign tumors in the skin, and the diverse morphological aspect, make their clinical diagnosis difficult. For this reason, histopathology helps doctors reach a definitive diagnosis.

Dermatologists are specialized physicians for the differential diagnosis of these tumors. So if you’re worried, just schedule a check-up with your specialist!

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