I bet, at least once, you may have worried about a lump that you had in your body, thinking that it might be a cancer. The frequent headache that you have been suffering from may have given you a suggestion of a brain cancer. Isn’t it? That’s how terrifying this disease is.
What is cancer?
Cancer or malignancy is an abnormal collection of rapidly proliferating cells inside the body. The cancer cells harbor numerous genetic mutations and cellular abnormalities that are classically not seen among the normal cells.
What is the reason for the abnormal cell division?
The genes, to be more specific; proto-oncogenes and tumor suppressor genes, are responsible for the cell cycle regulation. Proto-oncogenes stimulate cell division. Their activity is transient, activated only when the cell division is needed (e.g. – to heal a wound). The tumor suppressor genes are permanently activated. They inhibit the cell division to keep the size of the tissues under control. An activating mutation of a proto-oncogene or an inactivating mutation of a tumor suppressor gene is the core feature of any cancer. This mutation leads to excessive cell proliferation and subsequent acquisition of various downstream mutations, ultimately resulting in a cancer.
What are the effects of cancer?
Its cells require a high amount of energy and nutrients. Thus it sucks all the energy from your body and food, making you emaciated. As the tumor grows large, the local effects start to appear. This may be abdominal pain, chest pain, headache, difficulty in breathing or swallowing depending on the location of the lesion. Furthermore, these cells dislodge and travel through the bloodstream or lymphatics to be deposited at different locations. These deposits give rise to secondary masses, which are called Metastatic tumors. Lungs, liver, kidney, brain, and bones are notorious to have secondary deposits following most of the primary cancers. Advanced malignancies typically have multiple metastatic deposits, which drastically reduces the life expectancy of the person.
Symptoms and signs of a cancer
Most of the cancers don’t have particular symptoms. The symptoms usually are vague and non-specific, with a gradual onset and progression over several months or years. Several common symptoms of cancers are listed below.
- Sudden loss of weight (more than 10% over 6 months or more than 5% over 1 month)
- Loss of appetite
- Mild fever
- Night sweats
- A palpable lump which is typically firm and immobile
- Lymph node enlargement of the area
Types of cancers
It can virtually occur in any part of the body. Depending on the cell type that they originate from, classified as below.
- Carcinomas – epithelial cells in origin
- Sarcomas – connective tissue cells in origin
- Leukemia – originate from the bone marrow/ blood
- Lymphoma – originate from the lymphatic system
- Melanomas – originate from the skin
- Seminomas & Non-seminomas – Originate from testis or ovaries
The primary pathology of a cancer is genetic mutations. Occasionally, the mutations are inherited from the parents. (e.g. – BRCA1, BRCA2 genes for breast cancer, APC gene for bowel cancer) However, acquired mutations are much commoner. Following substances are known to be mutagenic and has the potential to induce cancer.
- Alcohol abuse
- Food preservatives including nitrates
- Arica nuts
- Estrogen hormone
- Some viruses including HPV, Hepatitis B & C viruses
- Fast foods
- Carbonated drinks
Diagnosis depends on the location and the symptoms of cancer. A full blood count and a blood picture may be enough to exclude leukemia. On the other hand, you’ll need sophisticated investigations like MRI or CT scan to exclude a brain cancer. If a visible lump or imaging suggests a tumor, a tissue sample from the lesion is taken either by a true-cut biopsy or fine-needle aspiration. It’s then further investigated to confirm the suspicion.
This ideal treatment is surgical excision. Excision is usually followed up by chemotherapy and radiotherapy to destroy any remaining malignant cells inside the body. In addition to these, specific modes of therapy are available for certain types of cancers; immunotherapy for leukemia.
If the tumor cannot be excised or the tumor already has spread beyond the capacity of surgical excision, palliative therapy is preferred to improve the quality of the remaining life of the patient.
Survival of a cancer patient/ prognosis
Survival of the patient depends on the extent to which the disease has invaded the body. If it already has spread throughout the body, life expectation becomes very minimal. Conversely, if the tumor is localized to its site of origin and is possible to be removed by surgical excision, a cure may be possible. However, the exact outcome of cancer depends on the type, location and complications of the cancer and the patient status.