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Carcinoma is one of seven forms of malignant solid tumors that develop in epithelial cells, which line the outer or inner surface of organs. Carcinoma accounts for roughly 80% to 90% of all cancer diagnoses. Epithelial cells coat the skin’s outer surface and can also be found covering and lining organs and internal passageways such as the gastrointestinal system.
Sarcomas, leukemias, lymphomas, blastomas, myelomas, and germ cell tumors are the other six forms of malignant solid tumors. Each has a varied effect on different types of cells.
WHAT ARE THE TYPES OF CARCINOMA?
Adenocarcinoma, basal cell carcinoma, and squamous cell carcinoma are the three major kinds of carcinoma.
- Adenocarcinoma: Adenocarcinoma is a form of cancer that affects organs or glandular tissues and can result in breast, lung, colorectal, stomach, prostate, pancreatic, and esophageal cancer, among other things. Common kinds of adenocarcinoma include hepatocellular carcinoma (liver cancer), renal cell carcinoma (kidney cancer), and cholangiocarcinoma (bile duct cancer).
- Basal cell carcinoma (BCC): The most frequent type of skin cancer is basal cell carcinoma. It affects basal cells (which generate new skin cells) in the lower epidermis (surface level of the skin). BCC is not a life-threatening condition for the vast majority of patients. It grows slowly and seldom spreads to other parts of the body. This skin cancer is highly curable if detected early.
- Squamous cell carcinoma (SCC): Squamous cell carcinoma, also known as epidermoid carcinoma, affects squamous cells (which make up the epidermis) and can result in skin, lung, oral head & neck, esophageal, cervical, vaginal, bladder, prostate, and penile cancer. After BCC, it is the second most frequent type of skin cancer.
Carcinoma types differ not only in terms of the organs they impact, but also in terms of their rate of advancement. BCC is slow-growing and less prone to spread than adenocarcinoma, whereas SCC grows quicker than adenocarcinoma. However, various molecular, cellular, hormonal, and physiologic variables can influence how quickly this and other malignancies grow and spread.
There are additional differences in carcinoma cell types, such as adenosquamous carcinomas, anaplastic carcinomas, small cell carcinomas, and big cell carcinomas, the characteristics of which can predict disease aggressiveness.
WHAT ARE THE CAUSES OF CARCINOMA?
Multiple genetic mutations can accumulate in a progenitor cell (a cell that can differentiate into a specialized cell, similar to a stem cell), and specific combinations of mutations can lead to the creation of a cancer stem cell, which creates cancer cells and causes cancer.
These cancer cells have the following characteristics:
- They are effectively “immortal,” as they do not perish as a result of planned cell death (apoptosis), as normal cells do.
- Because their growth is unregulated, they can reproduce exponentially.
- They are capable of penetrating surfaces and directly infiltrating neighboring structures.
- They have the ability to spread (metastasize) from the original tumor location to distant places, generally when cancer cells break off and are dispersed through the bloodstream or lymphatic system.
When mutations develop in the progenitor cells of the epithelium, they might result in either a benign (adenoma) or malignant tumor (carcinoma).
The cause of these mutations is not totally established. They are thought to be the result of a number of circumstances, including:
- Hereditary factors
- Asbestos, tobacco smoke, radiation, and industrial chemicals are all carcinogens.
- Viruses such as the human papillomavirus, hepatitis, and the Epstein-Barr virus
- Inflammatory diseases such as Crohn’s disease and ulcerative colitis
- Sunlight exposure
Age is a major factor in various malignancies. This is especially true for carcinomas, whose risk increases with age. According to the National Cancer Institute, the median age of diagnosis for breast cancer is 61 years old, for colorectal cancer it is 68 years old, for lung cancer it is 70 years old, and for prostate cancer it is 66 years old.
All of these are commonly related with cancer.
Recent research indicates that mutations may be present in noncancerous cells, indicating that they are unlikely to cause cancer on their own.
Scientists have yet to pinpoint which genetic alterations are linked to a certain type of cancer, or what other variables besides genes are to blame. BRCA mutations are a type of genetic abnormality that has been related to a variety of cancers.
HOW IS CARCINOMA DIAGNOSED?
Although imaging examinations (mammograms, CT, MRI), lab tests (cytology, PSA), and procedures (colonoscopy, thoracentesis) can be performed to screen for carcinomas in various sections of the body, carcinomas are firmly identified based on an inspection of the cancer cells under the microscope.
Because carcinomas are solid tumors, the investigation usually includes a biopsy (when cells or tissue are removed from your body to be examined under a microscope) to extract a tissue sample and morphology (physical structure) to identify the molecular, cellular, and architectural characteristics of the affected cells and tissues.
A biopsy may not necessarily indicate that you have cancer. Histology refers to the procedure of closer investigation with a microscope.
Biopsies are classified as follows:
- Bone marrow biopsy: Your healthcare professional will take a sample of bone marrow tissue with a biopsy needle. This technique is normally performed with local anesthetic.
- Endoscopic biopsy: An endoscope is a flexible tube with a light attached that can be used to access areas such as the lung or bladder.
- Needle biopsy: A needle biopsy may be utilized when a healthcare provider can feel a tumor through your skin. Fine-needle, core needle, vacuum-assisted, and image-guided needle biopsies are all types of needle biopsies.
- Skin biopsy: A skin biopsy is a procedure that extracts cells from the surface of your body in order to identify skin diseases.
- Surgical biopsy: When other methods of biopsy are unavailable or have yielded unsatisfactory findings, a surgical biopsy is frequently utilized. An incision is performed during this type of biopsy to extract a section of the cells in concern for further evaluation.
Carcinomas can be distinguished based on their morphology using tests such as:
- Gross examination: The biopsy specimen is examined with the naked eye.
- Section Frozen: A pathologist analyzes the tissue while it is frozen. It is frequently utilized during surgery for quick diagnosis.
- Description of the histology: The anomaly of the tissue is classified using a microscopic perspective.
- Description of cytology: Cytology examines cells and is capable of detecting minor changes at the cellular level to identify malignant or precancerous cells. It can detect the presence of aberrant cells, which may or may not be malignant but can raise the risk of cancer.
The differentiation of carcinoma cells can determine whether cancer would be aggressive or indolent. Because the cells are well-differentiated, they behave and respond similarly to normal cells, and the cancer is likely to progress slowly. Undifferentiated cells are highly immature and basic, and they lack the characteristics that are used to diagnose and classify different malignancies. Undifferentiated cancer is more aggressive than well-differentiated cancer.
These tests are utilized to not only diagnose but also stage and grade carcinomas.
WHAT ARE THE STAGES AND GRADES OF CARCINOMA CANCER?
Cancer staging is a means of categorizing the amount to which cancer has spread across the body. The majority of solid tumors are classified into the following stages:
- Stage 0: The cancer has only spread to the initial tumor and has not spread elsewhere.
- Stage I: The cancer has not spread to nearby tissues or lymph nodes.
- Stages II and III: The cancer has progressed to surrounding tissues and may have expanded to the lymph nodes.
- Stage IV: Because the cancer has spread to other organs, it is also known as metastasized cancer.
There are only two stages of small cell lung cancer (SCLC): limited and extensive.
Grading
By designating a tumor grade, cellular features inform the cancer stage and prognosis. The grade of the tumor aids in determining the appropriate treatment.
The following are the grades:
Grade 1: The cancer cells resemble normal cells (are well-differentiated) and develop slowly.
Grade 2: The cancer cells exhibit a greater degree of abnormalities and develop at a faster rate.
Grade 3: The cells have become undifferentiated.
Grade 4: The cells are undifferentiated and may be rapidly developing.
WHAT ARE THE TREATMENTS FOR CARCINOMA?
The therapy of carcinoma is determined by the location and size of the tumor, the stage and grade of the disease, and the individual’s performance condition.
The following are some general treatment approaches:
Chemotherapy: Chemotherapy is a pharmacological treatment used to kill rapidly developing cancer cells. Neoadjuvant chemotherapy is chemotherapy that is administered prior to surgery. Adjuvant chemotherapy is chemotherapy that is given after surgery.
Radiation therapy: Adjuvant radiation treatment is used after surgery. Palliative radiotherapy can be used to alleviate pain and improve quality of life.
Surgery: In the early stages, surgical excision usually provides the highest chance of long-term survival.
Immunotherapy: Immunotherapy is classified into two types; active and passive. Active immunotherapy engages your body’s immune system in the battle against cancer cells. Cancer vaccines and adoptive cell treatment are examples of active immunotherapy. Passive immunotherapy employs laboratory-created components to assist your body in responding appropriately to cancer. Cytokines (proteins involved in cell signaling) and immune checkpoint inhibitors are examples of passive immunotherapy.
Hormonal therapy: Hormones are used by both breast and prostate cancer cells to develop. Hormone treatment can be used to shrink a tumor before surgery (neoadjuvant therapy), increase the odds of remission, and kill cancer cells that have returned. Hormonal therapies are classified into two types: those that limit hormone production and those that modify hormone behavior.
Treatments might have a variety of objectives. Curative treatments, for example, are designed to encourage recovery and potentially lead to remission, whereas palliative treatments are aimed to alleviate suffering. Remission is a reduction or absence of illness signs and symptoms, whereas recurrence denotes the recurrence of malignancy.
A prognosis is the most likely result of a disease and might vary depending on the type and stage of cancer, as well as other factors. Survival rates, typically five-year survival rates, and, arguably, more crucially, disease-free survival rates, represent the prognosis.
CONCLUSION
Education is the most effective cancer prevention technique. You are more likely to find cancer early when it is most treatable if you identify your personal risk factors, including family history, follow regular screening guidelines such as mammograms, colonoscopy, and low-dose lung CT, and take the time to learn about the signs and symptoms of cancer.
Cancer is still not curable, but there are numerous choices for people with cancer to manage their disease and live their lives to the utmost. Enlist the help of family and friends to help you cope with the stress of not just being diagnosed with cancer but also living with it, and learn from others who have cancer about strategies to improve your quality of life.
