Cancer is a term used to describe diseases in which there is an uncontrolled division and growth of abnormal cells, which have the capacity to invade other body tissues (National Cancer Institute). Cancer is a major cause of morbidity and mortality; from 2006-2010, the incidence rate of all cancers in the US was 463 per 100,000 per year, with mortality being 176 per 100,000 (National Cancer Institute). This makes cancers the second leading cause of death. Cancer also has a huge economic impact, with total costs in the range of $200 billion in 2008 (American Cancer Society).
It is thus imperative for health practitioners to have a clear understanding of cancer so as to better care for, and educate, those diagnosed with or at risk for cancer. Diagnosis and Staging Today, there are many diagnostic modalities available to the clinician. The obvious first step to diagnosing any disease is a thorough patient medical, family and social history, followed by a physical examination. The choice of tests to use will depend on what cancer is suspected, the patient’s age and medical condition, and results of previous tests.
In cancer, an accurate diagnosis is very critical since different cancers require different therapies, many of which can be quite toxic. The most common diagnostic tests used are described. Biopsy A biopsy is the surgical removal of some tissue for the purpose of detailed examination by a pathologist under a microscope (American Society of Clinical Oncology, 2012). Biopsy enables definitive diagnosis by identifying the type of cancer, and the grade. There are different ways of removing the body tissue, again dependent on various factors.
Fine needle aspiration biopsy (FNA) is a relatively simple procedure that can usually be done in an office setting for tumors or cancers that are close to the skin. Fluid and a small amount of tissue can are aspirated through the needle and syringe enabling speedy, cost effective diagnosis. However, sometimes, the FNA may not get adequate tissue for a diagnosis (American Cancer Society). Core biopsies use a wider bore needle than FNA, enabling removal of more tissue for analysis, which is more likely to be adequate. Results usually take longer than an FNA.
Vacuum-assisted biopsy is a variant in which a vacuum pump is used to create suction, enabling even larger and multiple tissue samples to be removed through one needle insertion (American Society of Clinical Oncology, 2012). When the suspected cancer is deeper, or not easily felt, image-guided biopsy can be utilized. Imaging tests such as ultrasound, CT scan, MRI are used to localize the suspected area so that a needle can be guided in to remove the tissue sample. In some cases, a surgeon has to carry out a surgical biopsy by incising through the skin so as to get a tissue sample.
This is often done when a needle biopsy shows evidence of cancer cells, but definitive diagnosis has not been made. Tissues can also be removed through endoscopy or colposcopy (cervix). In bone marrow aspiration, tissue is removed from the bone marrow. Biopsy specimens are subjected to various studies, some of which are histochemistry, immunohistochemistry, electron microscopy and flow cytometry, which enable identification of specific cell types, and hence the origin of the cancer.
Genetic tests are also carried out to identify the type of cells, genetic abnormalities or defects that could be hereditary, and help in prognosis. These include cytogenetics, fluorescent in situ hybridization (FISH), PCR and gene expression microarrays (American Cancer Society). Laboratory Tests Blood, urine and body fluids are collected for assay. Complete blood counts (CBC) can help with the diagnosis of leukemia and monitor side effects of therapy. Tumor markers are special chemicals associated with specific cancers that are increased in the body when an individual has that cancer.
Examples include the prostatic specific antigen (PSA). However, their presence or absence does not confirm the diagnosis of cancer; they are however useful in monitoring response to therapy (American Society of Clinical Oncology, 2012). Imaging Tests These tests are usually not adequate to definitively diagnose cancer. They are useful in localizing the tumor for biopsy and assessing organ involvement and metastases. Different x-ray tests are used, e. g. mammography in breast cancer screening, and contrast x-rays in the gastrointestinal tract.
Bone scans and PET (positron emission tomography) scans use a radioactive isotope injected into the blood stream that concentrates in cancer cells, enabling visualization of cancer spread. CT scan and MRIs create 3-D images of the cancer within the body. These have the disadvantage of exposing the patient to radiation and potential anaphylactic reactions if contrast is used. On the other hand, ultrasound is cheaper and safe. Staging This is done to determine the cancer burden and location as these have clear prognostic implications and may affect the choice of therapy.
Staging considers •the site and type of the primary tumor,•the size and local extent, •involvement of regional lymph nodes, •presence of distant tumor masses (metastases), •tumor grade-how close to normal the tumor cells are in resemblance (American Joint Committee on Cancer). Staging can be done clinically, based on physical examination findings and imaging. Pathological staging is done with the addition of results from a surgical exploration. The TNM staging system is the most widely used and is based on •T-Tumor extent, ranging from Tx for cannot be evaluated, T0 for no evidence, Tis for carcinoma in situ, and T1-T4 for increasing size.
•N-for lymph node, again ranging from Nx, N0, to N1-N3. •M-for metastases: M0 indicates no distant metastases while M1 indicates that there are distant metastases. The T, N and M are combined and an overall stage is assigned. This is usually done using roman numerals I, II, III, IV. The stages can have further subdivisions using letters A, B, C, etc. Cancer Complications Different cancers cause different effects on the body; site and extent play a big role in this variance. At the same time, individuals may exhibit different clinical symptoms and signs in spite of having a similar diagnosis.
Pain This is common to many illnesses. However, in cancer, the pain can be distressing due to the chronic nature of the disease. Pain arises due to the cancer causing damage to surrounding tissue by invasion, inflammation and tissue destruction. Pain can also be iatrogenic-due to treatment or procedures carried out, e. g. biopsies, radiotherapy burns (Copstead & Banasik, 2013). The advent of patient controlled analgesia has led to much better pain control in cancer care. Opioids are commonly used, together with other analgesic classes to control cancer pain. Local Pressure Effects.
A large enough tumor can compress surrounding structures and cause obstruction. Examples include a locally advanced cervical cancer compressing the ureters and causing hydronephrosis and subsequent renal failure, pancreatic carcinoma compressing the common bile duct and causing obstructive jaundice, and intestinal obstruction from colon cancer. In these cases, the patient can die due to the failure of function occasioned by the obstruction. Prompt attention via bypassing the obstruction surgically or with stents is critical. In obstructive jaundice due to cancer of the pancreas, bypass surgery and stenting Cachexia.
Many cancer patients experience loss of weight and generalized weakness that can have many causes. Both adipose tissue and lean body mass are lost. Cachexia is due in part to an inflammatory response; cytokines (TNF, ILs) released from various cells in the immune system play a major role in this (Holmes, 2011). The body experiences an increased metabolic rate. Cancer patients are also usually anorexic, and suffer from nausea and vomiting, which further worsens the weight loss. Cachexia worsens the quality of life, increases the risk of premature death, and reduces the body’s ability to respond to therapy (Holmes, 2011).
Intense nutritional support is generally required through enteral and/or parenteral means (Copstead & Banasik, 2013). Bone Marrow Suppression Cancer cells are believed to secrete chemicals that suppress bone marrow function’ leading to neutropenia, anemia and thrombocytopenia. Cancer patients tend to have lower numbers of T and B lymphocytes, and experience increased incidences of infections. Poor immune function can result from bone marrow involvement primarily e. g. leukemia, or due to metastases Cancers are also believed to secrete chemicals that hinder immune function. Cancer treatment, especially chemotherapy, can also suppress the bone marrow.
This worsens the prognosis for cancer patients. Acutely, blood products can be used to correct anemia and thrombocytopenia-where leucocyte depleted products are preferred. All blood products should be irradiated (American Cancer Society). For leucopenia, colony stimulating factors, e. g. GMCSF/Filgastrim are used to stimulate WBC production. Managing Side Effects of Care Nausea and Vomiting Approximately 2/3 ds of cancer patients in the US survive to 5 years after diagnosis due to advances in therapy. However, with these care modalities come side effects, of which nausea and vomiting are very common.
Nausea and vomiting due to chemotherapy can be prevented or reduced by use of anti-emetics like phenothiazines (prochlorperazine), butyrophenones (droperidol/haloperidol), metoclopramide, 5-HT3 antagonists (ondanstron), steroids, cannabinoids (dronabinol/nabilone), aprepitant, and others. The choice of what anti-emetics to use depends on the emetogenic potential of the chemotherapy. Moderate to severely emetogenic regimens should be precluded by combination anti-emetics; a 5-HT3 antagonist is usually included (National Cancer Institute). Psychological Distress.
Cancer diagnosis and the treatment/surviving process is associated with psychological distress. This stems from fear and uncertainty of the future, whether there will be remission, or recurrence. Some of the techniques that can be helpful include •Education and support for the cancer patient adopting optimistic beliefs about their bodies and taking up self-health promoting activities. •Improved patient education so that they can understand the changes they are going through; this will also enable them feel like they still have some degree of control over their bodies as they will be able to understand and interpret any changes they perceive.
•Promotion of greater patient-clinician trust and communication. •Skills to help cope such as relaxation techniques e. g. yoga (Taylo, Richardson, & Cowley, 2011). Conclusion A diagnosis of cancer is bound to be one of life’s most stressful events, and is followed by multiple doctor/hospital visits, tests, procedures and therapies. The modern nurse needs to have a clear understanding of the current management practices in cancer care, including their side effects-and be proficient in recognizing such and managing them when they do arise.