The Pathophysiology of Cancer

Cancer describes a group of over 150 disease procedures typified by unrestrained development and spread of cells. Cancer does not refer to a one, certain disease but a group of changeable tissue responses that lead to unrestrained development of cells. Healthy tissues are made up of cells. Healthy cells have certain size, structure, purpose and rate of growth that serves well the requirements of the tissues which they are made of. Cancer cells don't look like the normal cells in size, function, structure, and growth rate. These nasty cells have shortage of normal controls of the development observed in healthy cells, and develop uncontrollably. Cancer cells are permitted by this uncontrolled growth to attack neighboring structures and then obliterate surrounding tissues and organs (Nelson and George, 1995). Malignant cells may also metastasize to other parts of the body via the cardiovascular or lymphatic systems. This unrestrained development and distribution of cancer cells can ultimately interfere with one or more of an individual's imperative organs or functions and most likely result to death. The bone, the lungs, the brain, the liver and the lymph node are the primary locations of cancer metastasis.

Furthermore, malignant cells lose their aptitude to differentiate or modify like normal healthy cells. Cancer are prevented from performing the duties needed by the tissues by this inability to differentiate hence resulting in a variety of other tissue changes in the body including pain, anemia, reduced immunity, leucopenia, cachexial, and thrombocytopenia. Some of these changes including pain can be benevolent although others signify a malignant or premalignant condition. Benevolent neoplasms or growth cells consist of the similar kinds of cells like the original parent cell though they don't have normal growth rates. Benign cells don't metastasize or attack surrounding tissues. However, they can pose an important in the body when they grow too large and compress very important organs or organ systems. The following will explain both malignant and benign tissue changes that take place in the body from irregular development and differentiation (Nelson and George, 1995).

Dysplasia is a universal group that points to a disorganization of cells. A cell in dysplasia differs from its normal parent cell in size, organization or shape. Dysplasia is usually the outcome of chronic irritation like the changes observed in cervical tissues from old irritation of the cervix. The first level of dysplasia- early dysplasia- is metaplasia. Metaplasia is a reversible benign though abnormal change observed when a cell changes from one type to another.

The most common type of metaplasia is in the epithelium of the respiratory tract where columnar epithelial cells change into squamous epithelial cells. Although metaplasia usually gives rise to an orderly arrangement of cells, it may sometimes produce disordered cell patterns. Disorderly cell patterns result in cells of the wrong size, shape or orientation lining up together and may result in inappropriate or faulty tissue behaviors (McCance & Roberts, 1998). Anaplasia is the loss of cellular differentiation. Anaplasia is the most advanced form of metaplasia and is a defining characteristic of malignant cells. An increase in the number of cells within a tissue in a section of a tissue is referred to as hyperplasia. Hyperplasia which leads in increased tissue size or mass can be a normal result of a specific physiologic changes or it can be a symptom of growth. Examples of normal hyperplasia are observed in the tissue increases that take place in the process of wound healing, callus formation after a bone fracture or breast mass rises during pregnancy. In Neoplastic Hyperplasia- in which there is a rise in cell mass because of growth formation is where an abnormal hyperplasia response is observed (Nelson and George, 1995).

Ulrich (1993) asserts that there are also substantial variations in the rate of growth of malignant tumors. Some tumors grow very slowly even in the state of malignant hence being easy to eliminate while other tumors may develop slowly at the beginning and then go through change and goes on to grow at a fast speed. Other kinds of tumor might develop very fast in all their entire survival. The status of an individual's immune system, the number of growth cells actively spreading, the rate at which growth cells are growing and the rate at which the normal tissues are being destroyed by the tumors are some of the factors that affect tumor and development. On the other hand, stress, advancing age, chronic diseases and malnutrition are some of the factors affecting normal immune function. Immune systems seem to be suppressed by cancer itself both at early and late in the process of disease.

Uncontrolled cell growth is a characteristic of cancer as described above. Proteins produced by the genetic materials within cells regulate cellular growth rates. Genetic material can be mutated or modified by environmental factors, errors with genetic duplication or revamp processes, or by cancer viruses. Oncogenes refer to altered or mutated genes and it is these oncogenes that permit unrestrained growth in cells (Sakamoto and Frank 2011).

Lung, prostrate, colorectal and breast are the most common and deadly cancers. Microenvironment of the metastatic tumor can adapt its biology and response to drugs. An image expressing the mechanism of metastatic was removed by Raymond showing primary tumor, detachment and invasion of the circulation, repeat, transport to a distant site, proliferation and angiogenesis, adherence to and extravasation, and arrest (Sakamoto and Frank 2011).

Stoma is invaded by tumor cells and communicates with stromal cells. This is due to the fact that tumor is avascular. Metastasis is facilitated by both tumor and host cells by making active growth factor pathways, permitting invasion, and facilitating angiogenesis. Metastasis is inhibited by tumors by being antigenic, unity- through e-cadherin, and by hindering angiogenesis. By putting up tissue barriers, sending immune cells to kill tumor, and inhibiting angiogenesis metastasis is inhibited by host cells.

When tumors secret angiogenic agents like VEGF and FGF, and using their lymphocytes and macrophages to secrete these agents as well leads to the occurrence of angiogenesis. The capillary DM degrades locally, developing a vascular malformation and permitting endothelial modeling. Macrophages or the tumor may also secrete anti-angiogenesis agents like angiostatin, thrombospondin and endostatin. Host stroma is invaded by tumor cells using enzymes then lymphatics or bloodstream- which have thinner walls. A fibrous ECM referred to as the desmoplastic response is the host reaction to this invasion (Sakamoto and Frank 2011).

According to Ragde, H, et al. (2000), one model for relapse is that dormancy has unrelenting minute pre-angiogenic metastases through which tumor cell growth is balanced by apoptosis. Spinal chord compression; presents acutely. This is usually the first symptom of cancer that has eaten the vertebrae, leading to density of anterior cord and roots. Cord is compressed directly by some paraspinous tumors through vertebral foremen. Back pain, exacerbated by lying down, coughing, percussion and bearing down is some of the symptoms followed by sensory and motor losses such as bladder or bowel function. MRI with gadolinium contrast is the gold standard for diagnosis while treatment consists of steroids, radiation and surgery.

Superior vena cava syndrome: quite a number of individuals presenting with SVCS have cancer. Regularly, a small cell lung cancer or Hodgkin's lymphoma might be as a result of vessel thrombosis external compression. Dyspnea, facial puffiness and flush, head pressure, engorgement of neck veins and collaterals over the chest are some of the symptoms. Diagnosis with the chest x-ray is one of treatment used and it consists of treatment with radiotherapy of necessary.  Cancer occurs most commonly with acute myelogenous leukemia, which plugs up capillaries with sticky young leukocytes. It can block oxygen to brain and lungs quickly and as well as the leukocytes struggling for oxygen and developing hypoxia. Endothelium gets damaged, and there is invasion of hemorrhage and cancer.  Acute dyspnea, tachypnea, chest pain, dizziness, fever, sensory changes, and stupor are some of the symptoms. Bilateral crackles are revealed by the physical exam. It is treated with hydration, urine alkalinization, alluporino- to avoid renal failure, and leukapharesis to eliminate leukocytes (Ragde, et al. 2000).

Hypercalcemia of Malignancy: Hyperparathyroid or malignant cancer, particularly breast cancer is the most common causes of hypercalcemia. Resorption is activated by metastasis at the bone or alternatively a distant tumor may secret humoral factors that rouse osteoclasts. 1, 25 dh D- usually secreted melanomas, since they make vitamin D, and PTH- usually secreted by carcinomas of the lung, kidney and melanomas are examples of such humoral factors if you observe hypercalcemia, think breast cancer or melanoma. Nauseau, polyuria, fatigue, vomiting, confusion, severe hypercalcemia, among others are examples of symptoms of hypercalcemia. Emergent treatment includes biphosphanates to interfere with osteoclasts, IV fluids and dieresis (Ragde, et al. 2000).

Paraneoplastic Syndromes: these are systematic impacts not connected with the direct invasion or compression from tumor. They consist of neurologic, hematologic derangements and endocrines. In most cases, small cell lung cancer causes such syndromes usually prior to diagnosis of cancer. Endocrine syndromes consist of ectopic ACTH, ADH, hyper/hypo calcemia and hypoglycemia. Ectopic ACTH is the most common endocrine paraneo syndrome because of small cell lung cancer or pheocromocytoma and causes Cushing's syndrome, which is hyperpigmentation, hypertension, hirsutism, metabolic alkalosis, hypocalemia and weight loss. Neurologic syndrome consists of numerous cerebellar and psychiatric functions such as agitation, memory probs, ataxia, confusion, sensory loss, and nystagmus. Work-up is supposed to comprise of brain MRI and lumbar Punture. The Eaton-Lambert Myasthenic Syndrome refers to a rare manifestation of small cell lung cancer. It is characterized by muscle weakness particularly in pelvic girdle. Muscle strengths improve with activity, and response to edrophonium chloride is poor in contrast to actual myasthenia and it is therefore important to be aware (Ragde, et al. 2000).

Hematologic manifestations of Cancer: trousseaus syndrome refers to systemic clotting also known as thrombophlebitis. It causes increased risk in pancreatic cancer and adenocarcinomas like prostate, breast and ovarian cancers. Gastronintestinal manifestation of cancer: it consists of anorexia, protein-wasting enteropathy and cachexia while weight loss is linked with shorter survival probably because of low food intake or to hypermetabolism (Blasko, et al 2000).

Pancreatic cancer is one type of cancer that has been affecting lives of many different people across the world. Pancreatic cancer is a silent and a dangerous disease that is accountable for 6% of cancer deaths within U.S. comprehension of the pathophysiology of pancreatic cancer relies first on the comprehension of the functions of the pancreas. The pancreas is both an endocrine and exocrine gland organ, situated behind the stomach and attached to the duodenum. It secretes enzymes into the small intestines that support digestion by assisting to breakdown carbohydrates, fats, proteins and acids (Blasko, et al 2000). Insulin hormones and glucagon which regulate blood sugar and stomatostatin which controls the other two are also secreted by the pancreas. There are very usual no symptoms or signs when a cancerous tumor develops until when it reaches an advanced stage. Understanding of this cancer needs learning about signs and symptoms, the inclining factors and whether it can be prevented (Blasko, et al 2000).

Abdominal pain, nausea or loss of appetite, unexplained significant weight loss, deep vein thrombosis, jaundice and depression are some of the symptoms of pancreatic cancer. Nevertheless, the pathophysiology of pancreatic cancer is also illusory since quite a number of the symptoms can have numerous causes. A patient, Particularly if they are middle aged or aged, usually chock their symptoms to other factors and delay visiting a doctor or don't see the need to visit one at all. Even the patients who visit a doctor are usually given wrong diagnosis prior to the final uncovering of the truth (Blasko, et al 2000).

Usually, the pathophysiology of pancreatic cancer results to abdominal pain that radiates into the back followed by dramatic weight loss and jaundice, and then probably depression. The pain will persist and worsen and the patient will finally search for a physician, or their treating physician will demand a liver function test which will disclose bile duct obstruction regular with pancreatic cancer.

There is no cancer that can be prevented completely and in order to help reducing probability of being infected with cancer, an individual is supposed to avoid smoking, eating a varied diet rich in fruits and vegetables, taking vitamin D and maintaining a healthy weight. Unluckily, the long term prognosis survival past two years is poor within the pathophysiology of pancreatic cancer. As a matter of fact, the median survival rate for pancreatic cancer is 3-6 months following diagnosis.

Potters, et al. (2002) portends that cancer has got some pain with bone pain being the most common although some neuropathic pain emerges from infiltration of nerves or organs. Well-localized, dull, aching pain characterizes somatic pain while poorly-localized, squeezing and deep resulting from infiltration or compression of viscera is characteristics of visceral pain. Neuropathic pains burns and itches as a result of invasion of nervous system. Complains of cancer pain are usually believed. More than 90% of cancer pains can be controlled. The ability to take large doses of drugs without ill effect is referred to as tolerance and it might lead in a resistance. On the other hand, the biological requirement for a drug so as to prevent withdrawal symptoms is referred to as dependence while addiction is the psychological craving for the drug. Functioning is measured using performance.  This is the main prognostic factor. The KPS and ECOG scales are the two major tests of performance status (Potters, et al. 2002).

Conclusion

Pathophysiology and therapy of cancer according to the approach outlined above requires physicians to have great deal of expertise. The most important goal must be to come up with the best possible treatment strategy. It is vital that we strive for a synthesis between scientific medicine and experience-based healing as well as treatment methods whether conventional or unconventional and the way they can be used meaningfully in providing the greatest help. While cancer is a multi-factorial condition, treatment must therefore beyond merely removing the tumour and instead, multi-component treatment must be employed with the aim of restoring order to the disrupted regulatory cycles in the body. In this respect, oncological after-care should not be restricted to the usual follow-up examinations, as it has been hitherto, but all patients who have undergone successful surgery should instantaneously be offered treatment to strengthen their immunity. There are a range of patients whose conventionally incurable tumours have shown lasting and absolute deterioration on biological therapy alone. This fact shows that the body has effective defensive mechanisms against cancer and gives us our justification for carrying out a treatment that activates these mechanisms that in turn helps patients. For sound theoretical reasons, we are less indebted to regard this all-embracing remedy with biological healing methods as an integral part of optimal cancer therapy.