Cancerhas a long history of troubling mankind as a disease itself. It often endsone’s life within a very short period of time. Thus, it can be quitedebilitating for the patients and their loved ones. Therefore, it is crucialthat treatment options for different types of malignancies are explored. Due tothe complexity of cancer cells and their mechanism of action, treatment optionsare very limited. Even today it’s an ongoing challenge to find a definite curefor this disease.
This further signifies the importance of continuing toconduct research into this area of medicine. Thesecancer cells have the ability to affect any part of the body and is characterizedby its uncontrollable and abnormal overgrowth pattern. It can rapidly create abnormalcells that grow beyond their usual boundaries and then invade the adjoiningorgans and distant parts as well (WHO, 2012). It begins to harm the body whenaltered cells divide uncontrollably to form lumps or masses of tissue calledtumors that are malignant. Itis reported as a leading cause for morbidity and mortality worldwide. In 2013there were 14.9 million cancer cases and 8.
2 million deaths. It is the secondleading cause of death globally, and was responsible for 8.8 million deaths in2015.
Globally 1 in 6 deaths is due to cancer. Number of new cases are expectedto rise by about 70% over the next two decades. Africa, Asia, Central and SouthAmerica account for 60% of total new cancer cases and 70% of cancer deaths inthe world (WHO, 2012). Fourteenout of fifteen Asian countries consist of 3.6 million males and 4.0 millionfemales living with cancer (diagnosed within the past five years).
Within the Asiancountries, colon and rectal cancers are most common among male cancer survivorsand breast cancer is the most prevalent among female survivors. Other mostcommon causes of death include lung, liver, stomach, breast, colorectal and esophagealcancer (WHO, 2012). Itis evident that cancer is a significant burden for many reasons. Not only ithave a great impact on the healthcare system, but it is also a financialburden. Among the male population, prostate cancer has become more frequent(1.4 million) while among the female population it’s breast cancer (1.8million). Incidence rates have increased in most countries since 1990.
Thistrend is a particular threat to developing nations with health systems that areill-equipped to deal with complex and expensive treatments. Thus, effectivemeasures must be taken to reduce cancer morbidity and mortality (Oncol, 2015). Ithas shown that five leading behavioral and dietary risks including high bodymass index, low fruit and vegetable intake, lack of physical activity, tobaccoand alcohol use are responsible for around one third of cancer related deaths.Most important risk factor among them is the tobacco use and it is accountedfor approximately 22% of deaths (WHO, 2012).
The impact of one’s genetic makeupalong with exposure to carcinogens play a major role in this. There are otherrisk factors such as age, hormones, infectious agents, radiation and sunlight whichalso contribute to the development of this disease. There are varioustypes of treatments available. The type of treatment depends on the type ofcancer and how advanced it is. Surgery, chemotherapy, radiation therapy, immunotherapy,targeted therapy, hormone therapy and stem cell transplantation are the maintypes of treatment.
The main goals of treatment include definite cure,prolongation of life and relief of suffering. Whenconsidering treatment options, priority is given for oral anti-cancer agents(OACA) which is classified under chemotherapy. Oral chemotherapy is notavailable for all types of cancers and it can be defined as any drug taken orallyto treat cancer by destruction of the malignant cells. OACA are used as single agents or incombinations and indicated for solid tumors and hematological malignancies(Timmers et al, 2012). OACA have different modes of action and differenttoxicity profiles. Majority ofantineoplastic drugs act by interfering with cell growth. These drugs can beused for cure, control or as palliative therapy. They have various mechanism ofactions.
These include the interaction with the process of cell division ofcancer cells and DNA, RNA synthesis. Furthermore, they can also interfere withvarious metabolic functions of cells disrupting normal cell function and alteringthe hormonal environment of the cell. OACA havebeen used in multiple types of cancer such as lung cancer, colon cancer, alongwith hematological and genitourinary cancers. Some commonly used oralanti-cancer agents are Capecitabine, Cyclophosphamide, Vinorelbine, Temozolamideand Mercaptopurine. Oralchemotherapy has many advantages like ease of administration and convenienceand the ability to reduce the need for invasive procedures. Oral therapy ingeneral is preferable in the patient population over parenteral therapy due toits ease and comfort. In addition, it does not cause significant damage tosurrounding organs as radiotherapy. There are some challenges associated withoral chemotherapy.
For instance, adherence to medication, understanding complexschedules and its different side effect profiles can be challenging. It canalso interact with food and other medications. There is always the risk of medication errors and the lack of safehandling procedures (Mahay, 2009).
Sincecancerous cells grow more rapidly than other cells. The drug can target other normaldividing cells as well. As a result, antineoplastic drugs will affect hairfollicles, gonad organs, lymph tissues and bone marrow. Some of the common sideeffects of these drugs are nausea, vomiting, diarrhea, loss of appetite, hairloss, mouth sores and skin changes.
These side effects of OACA negatively affectthe level of adherence.