Cancer: The Problem

Cancer can start any place in the body (in the lungs, the breast, the colon, or even in the blood). It starts when cells grow out of control. This makes it hard for the body to work the way it should.

Cancer is a leading cause of death worldwide, accounting for an estimated 9.6 million deaths in 2018. The most common cancers are:

  • Lung (2.09 million cases)
  • Breast (2.09 million cases)
  • Colorectal (1.80 million cases)
  • Prostate (1.28 million cases)
  • Skin cancer (non-melanoma) (1.04 million cases)
  • Stomach (1.03 million cases)

 


 

What is cancer?

Cancer is a group of diseases characterized by uncontrolled growth and spread of abnormal cells.

Cancer arises when normal cells transforms into the tumor cells. It occurs in a multistage process that generally progresses from a pre-cancerous lesion to a malignant tumor. Cancer cell arises by the interaction between a person's genetic factors with three categories of external agents, including:

  • physical carcinogens, such as ultraviolet and ionizing radiation;
  • chemical carcinogens, such as asbestos, components of tobacco smoke, aflatoxin (a food contaminant), and arsenic (a drinking water contaminant); and
  • biological carcinogens, such as infections from certain viruses, bacteria, or parasites.

 

Another fundamental factor for the development of cancer is ageing. The incidence of cancer rises with age because the mechanisms of cellular repair becomes less effective as a person grows older.

In cancer there is rapid creation of abnormal cells that rapidly grow beyond their usual boundaries, and which can then invade adjoining parts of the body and spread to other organs, this spreading of cancerous cells to other parts of the body is referred to as metastasizing. Metastases are a major cause of death from cancer.

What causes cancer?

Bellow mentioned are the risk factors for cancers;

  • Tobacco use
  • Alcohol use
  • Unhealthy diet
  • Physical inactivity
  • Some chronic infections 

Approximately 15% of cancers diagnosed in 2012 were attributed to carcinogenic infections, like H. pylori, Human papillomavirus (HPV), Hepatitis B virus, Hepatitis C virus, and Epstein-Barr virus.

Hepatitis B and C virus and some types of HPV increase the risk for liver and cervical cancer, respectively. Infection with HIV substantially increases the risk of cancers such as cervical cancer. 

Reducing the risk factors

By avoiding risk factors between 30–50% of cancers can be prevented. We can reduce the burden of cancer through early detection of cancer and management of patients who develop cancer. There are high chances of cure if a cancer is diagnosed early.

Modify and avoid risk factors

These risk factors include:

  • tobacco use (cigarettes and smokeless tobacco)
  • Obesity
  • unhealthy diet (low fruit and vegetable)
  • lack of physical activity
  • alcohol
  • sexually transmitted HPV-infection
  • other carcinogenic infections like hepatitis
  • ionizing and ultraviolet radiation
  • air pollution
  • smoke from household use of solid fuels.

Tobacco use is responsible for approximately 22% of cancer-related deaths in world.

 

Prevention strategies

To prevent cancer, people may:

  • avoidance of the risk factors
  • vaccination against HPV and hepatitis B virus
  • occupational hazards control
  • reduction in ultraviolet radiation exposure
  • reduction in ionizing radiation exposure (occupational or medical diagnostic imaging).

HPV and hepatitis B vaccination can prevent 1 million cancer cases each year.

 

In order to reduce the morbidity and mortality rates caused by cancer over the world, effective and affordable programs are required in;

  • early diagnosis
  • screening
  • treatment
  • palliative care

Treatment includes surgery, medication and/or radiotherapy. Treatment is planned on the basis of;

  • tumor type
  • stage
  • available resources

Palliative care is also very essential component of cancer care. It focuses on improving the quality of life for cancer patients and their families.

Early detection

Early detection and treatment can reduce the rate of Cancer mortality. Early detection has two components:

Early diagnosis

Early identification and diagnosis of cancer results in less morbidity, more probability of surviving, less expensive treatment, and patient is more likely to respond to effective treatment. 

Early diagnosis consists of three main steps, that needs to be completed timely:

  • awareness and accessing care
  • clinical evaluation, diagnosis and staging
  • access to effective treatment.

Early diagnosis is very crucial step in all cancers. If patient is not diagnosed early then curative treatment may no longer be an option in later stages of cancers. 

Screening

Screening aims to identify individuals with abnormalities who have not developed any symptoms.

Standardized screening tests help identify disease in asymptomatic individuals (screening) or diagnose a disease in symptomatic individuals (early detection). A screening program is far more complex as compared to early diagnosis.

Examples of screening methods are:

  • visual inspection with acetic acid (VIA)
  • HPV testing
  • PAP cytology test
  • mammography screening

Diagnosis and Staging of Cancer

 

Histological diagnosis of a tumor is most important step in the treatment selection. Because histologic classification influences its natural history, pattern of progression, and responsiveness to treatment. A biopsy followed by a microscopic and biochemical evaluation by a pathologist can provide the most accurate histologic diagnosis.

Staging is the process that determines the extent or spread of the disease. Tests that are more frequently used in cancer staging are;

  • Tests that can physically or radiographically measure the size of the primary tumor (e.g., radiographs, computed tomography [CT] scans, or magnetic resonance imaging [MRI] scans)
  • pathologically examine regional lymph nodes
  • Positron emission tomography [PET] scans are being used more frequently in cancer staging

Clinicians also evaluate symptoms like pain or signs like swelling, abnormal laboratory findings that may indicate the involvement of tumor.

 

 

Treatment

The goal of treatment is to to cure disease, prolong life, and improve the quality of life. A correct cancer diagnosis and staging is very important for effective treatment plan because every cancer type requires a specific treatment regimen.

Cancer is predominately treated with three modalities:

  • Surgery
  • Radiation (radiotherapy)
  • Systemic therapy (chemotherapy)

Surgery

Surgery is an important and the oldest treatment option for patients diagnosed with certain solid tumors. Surgery may be used as preventive (e.g., removal of colonic polyps or cervical dysplasia) or diagnostic treatment, or for staging of some cancers (e.g., biopsy for histologic evaluation).

Radiation Therapy

Radiation therapy can be used to treat localized solid tumors. Radiation may be administered as either curative therapy, adjuvant therapy, or palliative therapy. The damaging effects of radiation on the normal tissues that surround the tumor can be dramatic, and may be exacerbated if patients receive chemotherapy concomitantly or shortly after radiation.

Methods used to administer radiation to tumors are;

  • External-beam radiotherapy
  • Brachytherapy are two types of radiation
  • intraoperative radiation
  • hyper fractionated radiation
  • stereotactic radiosurgery
  • intensity-modulated radiation therapy
  • charged-particle(proton) radiation therapy

Chemotherapy

All cancers can’t be treated by surgery or radiation therapy. Some tumors have already metastasized at the time of initial diagnosis, whereas others have tumors that could not be completely eradicated with treatment or have recurred sometime after primary therapy with surgery or radiation therapy.

In these circumstances; Systemic treatments, including chemotherapy, targeted therapy, endocrine therapy, and biologic response modifiers are used to controll the disease. Systemic therapy was developed to treat advanced cancers but now these agents are used to treat earlier stages of malignant diseases also.

 

ANTI CANCER DRUGS

1) ANTI METABOLITES

  • 5-FLUROURACIL (GENERIC, CURACIL, FLURACIL)
  • 6-MERCAPTOPURINE
  • 6-THIOGUANINE
  • CYTARABINE
  • FLUDARABINE
  • METHOTREXATE

2) ANTI BIOTICS

  • BLEOMYCINE
  • DACTINOMYCIN (DAFLON, DALACIN C, DALACIN T)
  • DAUNORUBICIN
  • IDARUBICIN (ZAVEDOS, IDOGIL)
  • PLICAMYCIN

3) ALKYLATING AGENTS

  • CARMUSTINE & LOMUSTINE
  • CYCLOPHOSPHAMIDE & IFOSFAMIDE
  • MECHLORETHAMINE
  • STREPTOZOTOCIN

4) MICROTUBULE INHIBITORS

  • NAVELBINE
  • PACLITAXEL (TAXOL)
  • VINBLASTINE (VELBE)
  • VINCRISTINE (ONCOVIN)

5) STEROID HORMONES & THEIR ANTAGONISTS

  • AMINOGLUTETHIMIDES
  • ESTROGENS
  • FLUTAMIDE
  • GOSERELIN
  • LEUPROLIDE
  • PREDNISONE
  • TAMOXIFEN (TAMOXIN)

6) OTHERS

  • ASPARAGINASE
  • CISPLATIN (ZORID) & CARBOPLATIN
  • ETOPOSIDE
  • INTERFERONS (INTRON)
  • PROCARBAZINE

 

These drugs are available on  
https://www.drugscaps.com/

 

First important step is the determination of the goals of treatment and palliative care. Generally, the primary goal is to cure cancer or to considerably prolong life and also to Improve the patient's quality of life. Combination of above-mentioned therapies may also be used to achieve the desired goal.

Palliative care meets the needs of all patients and their families to improve the quality of life and ability to cope the disease effectively.

Cancers with high cure rates if detected early are;

  • breast cancer
  • cervical cancer
  • oral cancer
  • colorectal cancer
  • testicular seminoma
  • leukemias and lymphomas in children

Palliative care

Palliative care means to relieve the symptoms caused by cancer and improve the quality of life of patients and their families. Palliative care can help people live more comfortably when there is little chance of cure in later stages of cancer.

In palliative care 90% relieve can be achieved from;

  • Physical
  • Psychosocial
  • spiritual problems

 

Cancer and Pain

Pain is experienced by;

  • 55% of patients undergoing anti-cancer treatment and 
  • 66% of patients who have advanced, metastatic, or terminal disease.

Several physiological mechanisms in cancer causes pain including;

  • extension of cancerous cells into soft tissues
  • visceral involvement
  • bone involvement
  • nerve compression or injury
  • raised intracranial pressure
  • or a combination of these

Pain is an unpleasant sensory and emotional experience which is associated with actual or potential tissue damage, or it is described in terms of such damage.

Cancer and pain can also cause psychological suffering in the form of;

These factors can in turn exacerbate pain.

Drugs used in Pain Management

The goal of pain management is to relieve pain to a level that allows for an acceptable quality of life. 

Drugs used are;

      Non-opioids

  • Paracetamol
  • NSAID’s
  • Ibuprofen
  • Ketorolac
  • Acetylsalicylic acid

      Opioids

  • Codeine
  • Morphine
  • Hydromorphone
  • Oxycodone
  • Fentanyl
  • Methadone)

      Adjuvants

  • Steroids -Dexamethasone
  • Methylprednisolone
  • Prednisolone

      Antidepressants

  • Amitriptyline
  • Venlafaxine 

      Anticonvulsants

  • Carbamazepine

      Bisphosphonates

  • Zoledronate 

 

These drugs are available on  
https://www.drugscaps.com/

REFERENCES

  • Koda-Kimble and Young’s

Neoplastic Disorders In Applied therapeutics; The clinical use of drugs. Lippincott Williams and Wilkins, Inc. 10th edition, 2013. (page:2080 - 2108)

  • Richard A. Harvey

Anticancer Drugs In Lippincott’s illustrated reviews of pharmacology. Lippincott Williams & Wilkins, 5th edition, 2012. (page: 481-482)


 

Author's Bio: 

New York Times bestselling author Hamza Fox writes sweet, fun, action-packed mysteries. His characters is clever and fearless, but in real life, Hamza is afraid of basements, bees, and going upstairs when it is dark behind her. Let’s face it. Hamza wouldn’t last five minutes in one of his books.

Hamza is best known for his Southern Ghost Hunter mysteries and for his Accidental Demon Slayer books.