How To Detect A Skin Cancer (Part-II) ?
Basal Cell Carcinoma - What is It ?
From among the non-melanoma skin cancers, the two most common types are basal cell and squamous cell carcinoma. In this hub, I would try to put some light on self-detection of a Basal cell carcinoma.
Being a locally invasive cancer, basal cell carcinoma is made up of a cluster of cells resembling those found in the basal layer of the epidermis of the skin. It affects individuals between 4th and the 8th decades of life, of which more than 50% are males. More than 85% of these cancers occur in the head and neck region while those on the lower leg are more common in women.
The prevalence increases greatly with exposure to sunlight, but the best part of it is that despite being a tumor, it mostly remains confined to its origin and rarely metastasizes to distant locations.
The tumor develops most commonly on the eyelids, at the inner canthus (inner angle of the eye) and behind the ear. Those with fair or red hair, those who tan poorly and those who have had a history of childhood sunburns are at a greater risk while a past history of acne is protective.
Basal cell carcinomas grow slowly but become locally invasive and penetrate deeper structures, hence the name rodent ulcer.
Appearance of a Basal cell carcinoma
How to Identify A Basal Cell Carcinoma ?
Basal cell carcinoma most commonly presents as, "a pimple that does not go", or "a spot that fails to heal". The early tumors are small, translucent or pearly, raised and round areas covered by a thin layer of skin through which a few dilated superficial blood vessels show.
It can also appear as a small, pearly, red violet papule or a bulge; or as a small superficial ulcer that resembles an excoriation by a fingernail.
It may occasionally look like a small red, blood-filled balloon, pedunculated and resembling a pyogenic granuloma.
Different types of Basal Cell Carcinoma:
- Deeply eroding ulcer or Rodent ulcer - This ulcer has a typical rolled-out edge (not everted), often beaded and the floor shows scabbing at some places and breaking at others. If left, the tumor and its following ulcer may spread deeply and cause great destruction, especially around the eye, nose or ear.
- Nodular type - This type grows as a well marginated expanding nodule covered by skin that may periodically scale or erode and crust.
- Cystic type - This variant presents as a large, semitransparent nodule with a dark translucent appearance, as it contains fluid filled with a network of fiery red blood vessels on the surface.
- Pigmented nodule - This type looks like a mole and is found mostly on the face.
- Field fire or Forest fire or Geographical variety - With an advancing edge and a healing center, this variant has an irregular, raised edge around a flat, white scar.
- Morpheic variant - This basal cell carcinoma variant has a smooth surface that may be slightly raised above the normal level. The color is yellowish, resembling that of old ivory.
- Superficial type - In this type, the tumor patch is bounded by a slightly raised, thread like margin which is irregular in outline.
Basal cell carcinoma is a locally invasive tumor but in rare instances it may disseminate to distant sites via blood or lymphatics.
Identify a Basal cell carcinoma
Presenting Symptoms of Basal Cell Carcinoma
The most common presentation is a papule or nodule that may have a central scab or erosion. There is a waxy, pearly appearance with fine blood vessels easily visible on the surface.
The principal complaint is that of a persisting lesion - either as an ulcer or as a nodule. It is not painful in the beginning though it might frequently itch.
The lesion grows slowly and a little bleeding may be complained of. If untreated, the rodent ulcer becomes quite big and deep. It may then cause pain and bleeding and get infected.
Basal cell carcinomas are known for their multiplicity. Many small lesions may develop simultaneously, some well defined, while others in initial stages or just as dark patches of eczema.
Common signs that raise suspicion of a Basal Cell Carcinoma
- An open sore that bleeds, oozes or crusts. A persistent non-healing ulcer.
- A reddish patch or irritated area that crusts feels itchy or persists with no noticeable discomfort.
- A shiny bump or a pigmented nodule that resembles a mole.
- A pink growth with elevated rolled out border.
- A scar-like area with poorly defined borders.
Points to Remember When Suspecting A Basal Cell Carcinoma
Though no site is exempted, yet 90% of Basal Cell Carcinomas are seen on the face above the line drawn from the angle of the mouth to the ear lobule. The sites most favored by this cancer include the following:
- Around inner canthus of the eye.
- Around outer canthus of the eye.
- On and around nasolabial folds
- On the forehead, more common in females.
In fact, the rodent ulcer may be seen more commonly in places on the face over which tears roll down. That is why it is aptly called a "Tear cancer".
It may also develop on the scalp, neck, arms and hands (the exposed areas of skin).
The tumor always starts as a nodule. Gradually the center of the nodule breaks and an ulcer results. Such an ulcer has a rolled edge that is raised and rounded (not everted). As the growth spreads, the shape of the ulcer becomes irregular.
An irregular raised edge and a flat white scar is sometimes called a Field Fire or a Geographical basal cell carcinoma.
When the ulcer erodes deeper structures, the edge becomes more prominent but never gets everted.
The floor of the ulcer is covered with a coat of dried serum and epithelial cells. If this sheds off, the ulcer will bleed.
The base of an ulcer is formed by the structures which the tumor is eroding - either fat or muscle or bone.
Types of Basal Cell Carcinoma
Rolled out, beaded edge
Well marginated expanding nodule
Thread like margin
Spreads deeply causing great destruction
Scar like appearance
Floor of ulcer shows scabbing
Resembles a mole
Common Modalities of Treatment for Basal Cell Carcinoma
- Radiotherapy - The tumor is highly radiosensitive, with an overall response rate being 92%. It is reserved for elderly who are not suitable for surgery and for certain specialized anatomic sites.
- Surgery - This mode of treatment is used when the tumor has recurred after being treated by radiotherapy and when a new lesion appears adjacent to a previously treated area. About 3-5 mm of healthy surrounding is excised with the tumor in all three dimensions.
- Moh's micrographic surgery - This consists of removal of the tumor followed immediately by frozen section and histopathological examination of margins with subsequent re- excision of tumor-positive areas and final closure of the defect. This method gives the highest cure rates of 98%.
- Local chemotherapy with 5- Fluorouracil cream.
- LASER beam destruction
When to suspect a Basal Cell Carcinoma ?
Prognosis of a Basal Cell Carcinoma
Basal cell carcinomas can be easily treated in their early stages. The larger the tumor has grown, however, the more extensive is the treatment needed.
This cancer sometimes resembles non-cancerous skin conditions such as psoriasis or eczema that only a trained physician can decide for sure.
If you observe any of the above-mentioned signs or some other worrisome change in your skin then consult your physician immediately.
An individual who has had one basal cell cancer treated should always be followed up, not only for local recurrence but also to detect fresh tumors arising elsewhere.