Basal cell carcinoma: causes, symptoms, treatment methods, Diagnosis
Epithelial tissue – one of the most common in the human body. It covers the whole body, forming together with the dermis skin lining the hollow organs of the gastrointestinal tract, urinary and genital tract. One of its main features – a permanent renewal of cellular structure due to the continuous reproduction of cells of the basal (deepest) layer.
Frequent division of cell nuclei leads to an accumulation of errors and mutations, which in some cases is the cause of malignant transformation. Basal cell carcinomas (basal cell cancer, basal cell carcinoma , basal cell epithelioma) – a cancerous tumor formed from the basal epithelial cell layer.
Basal cell carcinoma is known to mankind since ancient times: modern researchers have found signs of it in Egyptian mummies and human remains that are aged for at least two millennia. The first detailed description of the tumors was done in the mid-19th century and at the beginning of the 20 th scientists proved its epithelial origin. The reason for this interest in the basal cell carcinoma – is its broadest distribution, it is considered one of the most common tumors in humans. The incidence of basal cell carcinoma in our country is 270 cases per 100 000 people, and is second only to lung cancer in frequency.
How to develop?
To date, there is no single answer that leads to cancerous degeneration of normal cells. cell division errors – is uncommon in living tissues, especially intensively growing. However, in the body there is an effective system to prevent cellular atypia: T lymphocytes, according to their maturation learn to distinguish between normal healthy cells from the modified and destroy the past. Consequently, the occurrence of basal cell carcinoma – a two-way process: on the one hand are all reasons genome damaging the cells, on the other – lack of immune protection.
The factors leading to the growth of the tumor, may include:
permanent injury to the skin area;
age-related changes in skin;
epidermal damage chemicals.
These factors combined with congenital predisposition and inefficient T-cell immunity leading to degeneration of the cancer cells of the basal layer of the epidermis. They lose touch with other epithelial cells acquire the ability to divide indefinitely, they synthesize unusual proteins and can no longer perform its normal functions. carcinoma cells release substances that promote the growth of new blood vessels that will supply the sprawling tissue.
Basal cell carcinoma – a slow growing tumor with a relatively benign course. Her cells divide slower than normal epithelial cells, many of them die than usual due to the small size of the tumors. However, basal cell carcinoma, like all cancers, is able to grow into the adjacent tissue (fascia, muscles, bones) and metastasize.
What types of tumors are?
According to the cellular composition can be basal cell carcinoma (WHO, 2006):
surface – changes affect only the surface layers of the skin;
junction (nodular, solid) – unit assembly is formed in the skin;
micronodular – tumor consists of several small nodules;
infiltrative – germinating into the underlying tissues, blood vessels and nerves;
fibroepithelial – in combined tumor epithelial cells and connective tissue elements;
with pridatkovoy differentiation – in carcinoma cells mature, similar in structure to the ovarian;
bazalnoploskokletochnaya bazalioma with keratinization – part of the cells in the tumor is completely filled with a dense protein keratin and die.
Oncologists in their work are TNM classification, which allows them to assess the outlook for a number of signs of the disease. The letter T refers to the process prevalence:
Tis – tumors “in situ”, ie without departing from the basal layer of the epidermis. This microscopic formation consisting of several altered cells which can detect coincidence histological examination of the skin;
T1 – basal cell carcinoma spreads over the whole thickness of the epidermis and dermis can grasp, but it does not exceed 2 cm Simultaneously with it the patient revealed no more than 2 of high risk factors;.
T2 – the tumor is larger than 2 cm, or the patient has more than 2 high risk factors, regardless of the size of a neoplasm;
T3 – the tumor grows in the bones of the skull;
T4 – a tumor grows in the bones of the skeleton, or cranial nerves.
Factors in high-risk aggressive course and metastasis of basal cell skin cancer are:
neoplasms of thickness more than 2 mm;
germination in the nerve trunks;
Localization carcinomas red border of the lips or in the ear;
low differentiation (maturity) tumor cells.
The letters N and M are characterized basal cell carcinoma metastases:
N0 – no metastases in regional lymph nodes;
N1 – lymph node metastasis in the unit on the affected side, lymph node size of less than 3 cm;
N2 – Metastasis in a single lymph node on the affected side (2a) / the other (2b) / both sides (2c), lymph node size of 3-6 cm;
N3 – metastases in the lymph nodes that are larger than 6 cm;
M0 – No distant metastases (more regional lymph nodes);
M1 – distant metastases is.
Thus, the initial stage of basal cell carcinoma is denoted as Tis N0 M0 – microscopic tumor size of only a few cells.
How does cancer?
In 90% of cases of basal cell skin cancer is localized on the head, along the lines of embryonic closure of skin flaps: nasolabial folds, the nose, on the border of the orbit of the eye and the ear. On body areas covered by the sun develops a tumor is much less and can be located on any part of the body, including the perianal folds, soles of the feet and palms. Basal cell carcinoma of the skin, patients notice the very early stages, but seek help only when a non-healing ulcer or tumor invasion into the underlying tissues. This is due to the slow growth of carcinoma, its seemingly harmless and the absence of pain, general malaise.
The clinical picture of basal cell carcinoma depends on its type.
Nodular form is considered a classic, because this type occurs 60-75% of all basaliomas. The skin appears tight knot with a diameter up to 5 mm, similar in appearance to a rounded drop of wax. It is different in color from the surrounding areas of the epidermis, its surface smooth, translucent. Through it shine red nodules – numerous blood vessels feeding the tumor. Education is growing very slowly, after a few years, it has reached 1-2 cm in diameter. Fast growth rate occurs in people of old age, and in patients with a significant reduction of immune protection, in particular of T-cell (HIV-positive).
If the tumor merge multiple nodes, then it becomes a rough edge, it protrudes in the form of a roller. Mid carcinomas frequently decomposes to form small bleeding ulcer, whose surface is covered by a dry crust. A similar process can be transformed into a variety of tumor ulcer. In this case, in place epithelioma formed ulcer 1 cm wide, funnel form, which is practically treatable and periodically bleeds. Sometimes ulcerative defect substantially destroys the structure of the face, especially if it is localized nearby orifices (nostril, external auditory canal, eye).
Sometimes, basal cell carcinoma cells contain pigment dark brown or black – the melanin, which is partially or fully stain it. May be formed within the tumor cavity filled with a liquid or thick muddy mass – cyst.
Superficial basal cell carcinoma – the most benign type of tumor with a favorable prognosis. The skin appears pink plaque diameter of from 1 to a few cm, the surface of which can be peeling, peel, and enhanced weakened portions pigmentation atrophy. Edge it does not protrude above the surface of the skin and is bordered by a chain of brilliant whitish bubbles. Externally carcinoma resembles psoriatic or fungal skin lesions that usually requires careful differential diagnosis. The tumor grows slowly over the years and can not be treated dermatological preparations.
How is cancer?
Treatment of basal cell skin cancer – a task oncologists. They also establish a definitive diagnosis. Usually with skin lesions, ulcers, patients were treated by a dermatologist, who immediately suspects or malignant nature of the disease, or focused on the ineffectiveness of standard therapy and sends the person for a consultation with an oncologist. The main goal of treatment of a tumor – to completely remove or destroy it, for which the following techniques:
surgical removal – surgeon cuts basal cell carcinoma and 4-6 mm tissue around it to prevent further growth;
Mohs technique – layering is removal of the tumor with histological examination of each slice. Treatment time-consuming, costly, but brings good results;
cryodestruction – treatment of small superficial lesions, carried out on an outpatient basis with liquid nitrogen. Carcinoma cells undergo freeze, which leads to their immediate death;
curettage, electrocoagulation – a scraping sharp tool box epithelioma followed by cauterizing the edges and bottom of the wound;
radiotherapy – irradiation detrimental radiation carcinoma cells (x-ray, gamma rays);
laser – the destruction of neoplasms laser beam is only applied when the surface shape of the formation;
drug therapy – for the treatment of tumors administered drug that inhibits cell division (cytostatic). The method is suitable for patients with multiple carcinoma, which are not suitable radiation therapy and surgical removal.
Forecast of basal cell carcinoma in most cases favorable, it has successfully cured the listed methods and rarely metastasizes. However, recurrent epithelioma – it is an alarming sign, which indicates a high risk of adverse outcome of disease. Difficult to treat tumors in elderly people and in those with persistent decline in immune defense.
Read about: Bipolar disorder sign