Moles & Skin Bumps
There can be lumps and bumps on our skin. What are they? Are they non-cancerous or cancerous? Over here at this page we will discuss non-cancerous common moles and other skin bumps like sebaceous cyst, lipoma, neurofibroma, keratoacanthomas, hemangioma, dermatofibroma, Seborrhoeic keratosis and warts. Cancerous molesmelanoma will be discussed under the page “skin cancer”. Warts will be discussed at another website.
Melanocytic Nevi (Moles)
Moles are melanocytic nevi which are common findings on anyone’s skin. It is due to the proliferation of the skin pigment cells called melanocytes. They can be brown to black color. They are not cancerous as compared cancerous moles (melanoma).
Congenital melanocytic nevi are moles that occur at birth as a result of congenital malformation. Acquired forms are those that occur after birth usually in the middle aged groups. It has certain genetic predisposition and also with increased sun/ultra-violet exposure. It occurs more commonly in fair-skinned people.
Normal acquired non-cancerous moles are commonly homogenously tan-brown to black color and usually less than 1 cm.
Congenital melanocytic nevi can be small (<1cm), intermediate (1-3cm) or large (>3cm). They are generally evenly pigmented tan or brown in color.
Dysplastic melanocytic nevi (Clark Nevi) are sometimes the precursors ofmelanoma (cancerous moles). They look like flat pigmented macules/papules. It resembles “fried egg” with central zone papular area surrounded by macular area of darker pigmentation.
There is no diagnostic laboratory test for moles; diagnosis is made by clinical features. Excision of the mole by shave biopsy or punch biopsy can be sent for histological confirmation of diagnosis if in doubt.
Management: As the moles are usually benign (non-cancerous), no intervention is required. Patient should observe for changes in the size of the mole, color changes, ulcerative changes or irregularity in mole. If so, consult the dermatologist again. Non-cancerous moles are often removed mainly for cosmetic reasons.
Risk factors for melanoma (cancerous moles)
1.Number of acquired moles: If patients have > 100 moles or Caucasians with > 40 moles by age 50, there is an increased risk of having a cancerous mole.
2.Dysplastic Nevi as discussed earlier is sometimes pre-cancerous moles.
3.Personal history of melanoma is also a risk factor.
4.Prolonged and excessive sun exposure as well as severe sunburns predispose to cancerous moles.
5.Large congenital nevi larger than 20 cm has increased risk of melanoma.
6.Certain genetic constitution may predispose one to melanoma.
Features of melanoma
Certain features distinguish a melanoma from a normal mole. If the mole changes in shape, size, color and if patient has symptoms of itch or bleeds then the patient should seek a dermatologist advice. The appearance of a mole suspicious of a cancerous melanoma can be remembered by mnemonic ABCDE. The suspicious cancerous melanoma will be Asymmetric, Borders of mole are irregular, Color is variegated, Diameter (increases in size) and Erosion/elevation (ulcer forms).
What is Seborrhoeic keratosis?
Seborrhoeic keratosis is common harmless “wart-like” growths found more in older individuals. Hence they are also sometimes called senile warts. They resemble moles and can be mistaken as one. They are more common among fair-skinned people.
The exact cause of Seborrhoeic keratosis is unknown. Sunlight exposure may be a contributing factor. They develop from proliferation of epidermal cells as part of ageing process.
Clinical presentation of Seborrhoeic keratosis
Usually Seborrhoeic Keratosis does not have any symptoms although some may itch and get inflamed after scratching. They usually begin as well demarcated light brown flat macules (brownish spots). Their surface slowly turns velvety followed by rough warty-like surface with plugged follicles (may appear to be stuck on skin). The color varies from pale brown to dark brown to black. The size may increase with time.
The sudden appearance of multiple eruptive Seborrhoeic keratosis is a Leser Trelat Sign which is associated with cancers of the gastrointestinal tract (adenocarcinoma), acute leukemia and lymphoma.
Usually diagnosis is clinical. Investigation is only required if there is Leser Trelat sign mention above suggestive of an association with certain cancers. Skin
Treatment of Seborrhoeic keratosis is usually not required as they are harmless. Most of the time they are removed due to cosmetic reasons. Topical treatment with tazarotene cream, ammonium lactate and alpha hydroxy acids may reduce the thickness of the Seborrhoeic keratosis.
Surgically it can be removed by cryotherapy (freeze with liquid nitrogen), shave biopsy, curettage & cautery and laser surgery.
What is Sebaceous Cyst?
Sebaceous cysts are a form of epidermoid cysts which are swelling in skin arising from the sebaceous sweat gland. They are harmless non-cancerous bumps that can occur anywhere on the body. They can occur at any age and are more common in men than women.
Gardner’s syndrome is a rare genetic disorder that causes multiple skin epidermoid cysts and growths in the colon.
It may be caused by occlusion of the sebaceous gland, damaged to the hair follicle, development defect or genetic disorder like Gardner’s syndrome.
Sebaceous cysts are flesh colored to yellowish in colored firm round nodules. They can be variable in sizes. There is usually a central punctum/pore present. When the overlying skin is broken, cheese-like foul smelling discharge may ooze out. Sometimes they may get inflamed and infected.
Treatment: Laboratory tests are not necessary as diagnosis is clinical. Sebaceous glands are harmless hence they can be left alone. If infected, they can be treated with antibiotics and incised and drained out. Intra-lesional corticosteroid injections may reduce the inflammation too. Some people choose to surgically remove it due to cosmetic reasons.
What is Lipoma?
Lipoma is a non-cancerous slow growing skin tumor made up of fat cells. They affect both sexes equally and usually develop in adulthood. Women tend to have solitary lipoma whereas men tend to get multiple lipomas.
The exact cause of lipoma is unknown. Trauma to skin has been hypothesized to trigger lipoma formation. There may be some genetic involvement too.
Lipomas do not usually cause any symptoms and they grow slowly over years. The look like dome shaped lump and their size can range from 2 to 20 cm. It is soft, fluctuant and slips away and moves under the skin (slippage sign). They can occur anywhere on the body where there is fat tissue. They arise from the fatty tissue between the skin and the deep fascia.
Treatment: As they are non-cancerous, tests and treatment is not required. They are usually removed due to cosmetic reason either by liposuction or by surgical excision.
What is neurofibroma?
Neurofibromas are common non-cancerous skin growths of a condition called neurofibromatosis type 1. Neurofibromas are made up of Schwann cells, fibroblasts, mast cells, and vascular components. They can occur anywhere along a nerve. Their color ranges from skin-colored to pink to brown. They can be soft to firm to touch and are often pedunculated button like lesions.
Neurofibromatosis is a genetic disorder that can affect the skin, soft tissue, bones and nervous systems. There is Type 1 and 2 neurofibromatosis. Neurofibromatosis is caused by genetic defects.
Type 1 Neurofibromatosis is characterized by freckling at the axilla (armpits), 6 or more café au lait spots (>0.5 cm oval shaped light brown patches), multiple Neurofibromas and Lisch Nodules (tiny tumors of the eye iris).
Type 2 Neurofibromatosis is characterized by multiple tumors in the brain, spinal cord and acoustic Neurofibromas. The tumors grow on the auditory nerve and lead to deafness.
There is no cure for neurofibromatosis. Treatment is aim at early intervention and monitor development. Affected patients should undergo genetic counseling.
What is keratoacanthomas?
Keratoacanthoma is a low grade tumor that originates in pilosebaceous glands and resembles squamous cell carcinoma. It is a skin lesion that erupts over sun-damaged/hair-bearing skin area. It grows rapidly over few weeks to months followed by spontaneous resolution over the next 4 to 6 months.
Keratoacanthoma is less frequent among dark-skinned people. Male to female ratio is about 2:1. It can occur at any age but more common as one age.
The exact etiology for formation of keratoacanthomas remains unknown. Sunlight, chemical carcinogens, trauma/injury, HPV virus, genetic factors and immunocompromised state may predispose one to form keratoacanthomas.
Keratoacanthomas often occur at sun exposed areas like the face, neck and the upper limbs. They are usually single lesions that begin as round, firm, skin-colored/reddish papules that will progress to dome-shaped nodules with smooth surface but with a central ulcer or keratin plug which may grow into a horn.
Treatment: As keratoacanthomas resembles squamous cell carcinoma hence excision biopsy and histopathology confirmation of the lesion is warranted for diagnosis.
Keratoacanthoma can be removed surgically by excision, cryotherapy, curettage & cautery and also by radiotherapy. For patients who are poor surgical candidates, then intra-lesional methotrexate (MTX),  5-fluorouracil, bleomycin, and steroids can be used.
What is hemangioma?
Hemangioma is benign non-cancerous tumor of the cutaneous blood vessels. Infantile hemangioma may develop shortly after birth and the will grow to a maximum size up to 3-5 months. Some may grow until 18 months after which they will slowly regress over 3 to 10 years. Up to 50% may not completely resolve and may leave a dented scar.
60% of lesions are found in the head and neck regions, 25% are found in the trunk and 15% found in the extremities. The hemangiomas can also be found in the larynx, liver, gastrointestinal tract, spleen, gallbladder, thymus, lung, adrenal glands and bladder.
The superficial infantile hemangioma involves blood vessels in the uppermost layers of the skin and is called strawberry hemangioma/ strawberry nevus or capillary hemangioma. Deep infantile hemangiomas are found deeply in the dermis or subcutaneous area. They are called cavernous hemangiomas.
The size of hemangiomas can range from small 0.5 cm to as large as 20 cm. They are usually red or crimson in color spongy mass that protrudes from the skin. Sometimes the hemangioma may ulcerate, bleed and get infected.
Diagnosis is clinical and so diagnostic tests are not required. Deep infantile hemangiomas involving organs may require ultrasound or MRI scans to detect the extent of the lesion.
Treatment: as most infantile hemangiomas resolve with time, they do not require treatment. For those that persist or cause complications they can be removed surgically by excision or by laser surgery. Oral and intra-lesional corticosteroids may slow the growth and proliferation of hemangioma. Beta blockers medications like propranolol and topical timolol may also be used.
What is dermatofibroma?
Dermatofibroma is a common non-cancerous fibrous skin lesion. It is sometimes called fibrous histiocytoma. It occurs more commonly in women. It usually develops in young adulthood.
The exact etiology is unknown. Sometimes they arise from an area of minor injury like insect bite or prick. Dermatofibroma usually occur slowly as a single lesion that commonly in lower legs and arms. They do not usually cause symptoms but sometimes they cause pain and itch. The dermatofibroma nodules range from 0.5 to 1 cm in diameter. These firm nodules color ranges from pink to skin colored to brown-black. If the skin over the dermatofibroma is squeezed a dimple forms which indicates tethering of the skin to the underlying fibrous tissue (dimple sign).
Dermoscopy is good way to diagnose dermatofibroma. It will reveal a homogeneous pattern with shades of yellow and a peripheral pigment network. Diagnosis is clinical. To confirm diagnosis, excision biopsy with histopathological finding can be done.
Treatment: As dermatofibroma is non-cancerous, no treatment is required. They are usually removed surgically because of cosmetic reasons. They can be removed by cryotherapy, surgical excision and bycarbon dioxide laser.