Colorectal cancer (CRC) is the term for a cancer of any part of the large bowel, from the caecum, which lies next to the ileocaecal valve, to the anus. Cancers of the anus are relatively rare, however, and account for only 4% of all new cases of colorectal cancer reported each year in the UK (Jones and James, 1993).
VOL: 97, ISSUE: 11, PAGE NO: 39
Julia Breeze, MSc, ANP, SRN, RSCN, is lead nurse, colorectal and stoma care services, Royal Free Hampstead NHS Trust, and chair, RCN Gastroenterology and Stoma Care Nursing Forum
CRC is the second most common cause of cancer-related death in the UK (King’s Fund, 1990). About 25,000 new cases are reported each year (Schofield and Jones, 1993) and about half of these are fatal.
The causes of CRC are largely unknown, but it is thought to be related to diet. This is because it is rare in Africa and Asia, but African and Asian people who are born and raised in a western culture are as likely to develop it as their white counterparts (Souhami and Tobias, 1998). A high intake of animal fat (Willett et al, 1990) and a low intake of dietary fibre appear to be risk factors. A high intake of alcohol appears to increase the risk.
A regular intake of aspirin or a similar drug from the same family, such as the aminosalicylate mesalazine - which is used in the treatment of patients with inflammatory bowel disease - appears to protect against the development of CRC (Logan et al, 1993; Eaden et al, 2000).
Screening for CRC
Several medical conditions may lead to CRC, and these and the screening procedures for them are summarised in Table 1. Screening procedures vary at local level, depending on the clinician’s preference and financial constraints. General screening is not available, but the effectiveness of faecal occult blood testing and flexible sigmoidoscopy as screening procedures is being explored (Kronborg et al, 1989; Chamberlain, 1990).
The symptoms of CRC vary depending on the site of the tumour. The most common are rectal bleeding and the development of constipation or diarrhoea, or a combination of both conditions, which persists for longer than three weeks.
Careful history-taking has revealed that more than 60% of patients have at least two symptoms (Souhami and Tobias, 1998). Thorough and knowledgeable questioning also reveals that 65% of patients with the disease present with a lesion on the left colon, that is the descending or sigmoid colons or the rectum (see Fig 1). These regions are relatively easy to reach with a flexible sigmoidoscope.
Clinicians may, however, reach different diagnoses using the same set of symptoms. For this reason scans or X-rays and a biopsy, which is usually taken during colonoscopy, are vital to establish a definitive diagnosis before treatment is planned.
Pathology and staging
Ninety-eight per cent of cancers of the large bowel occur above the anus and almost all are adenocarcinomas, which arise from an adenomatous polyp in the epithelium. The stage of the cancer is usually determined preoperatively by performing a staging computerised tomography scan of the pelvis, abdomen and thorax to obtain information on the presence or absence of metastatic disease.
After surgery, the pathological stage of the disease is determined. Any decision to administer chemotherapy is based on this. Pathology is also used to predict the life expectancy of each patient.
Pathological staging is based on the work of London pathologist Cuthbert Duke (1932), which is used around the world in a modified form, and tumour, node and metastasis (TNM) staging (Hermanek and Sabin, 1995). Table 2 (see p41) lists the stages of these two main forms of pathological staging alongside five-year survival expectancy.
Surgeons sometimes question whether patients should be given a detailed explanation of these stages, but they need to know the full facts if they are to make choices about their treatment and lifestyle options. It is, however, vital that this information is delivered with sensitivity.
Management of CRC
Like most types of cancer, the treatment options for CRC are surgery, radiotherapy and chemotherapy.
If the tumour is considered to be resectable, the surgical options all involve a laparotomy, which involves a midline surgical incision and the opening of the abdomen. But the particular procedure used depends on the site of the tumour (Table 3 and Fig 2, both overleaf).
All patients having a bowel resection should be told that a stoma may need to be created, but if surgery is planned and there are no complications most do not require even a temporary stoma. The nursing issues involved in caring for a patient having a laparotomy and bowel resection are summarised in Table 4 (overleaf).
Chemotherapy has been used for some time as a treatment for patients with metastatic disease and as a postoperative (adjuvant) therapy, but it is a relatively new form of treatment for patients with CRC. Duke’s A-stage patients do not need any chemotherapy, but it should be offered to most B-stage patients and all C-stage patients.
The standard treatment, which begins about six weeks after surgery, involves the use of mainly 5-Fluorouracil and folinic acid. Patients on this regime should be told that they will probably have side-effects such as nausea and diarrhoea.
Radiotherapy is used mainly as a presurgical (neo-adjuvant) treatment for cancers in the lower rectum (Souhami and Tobias, 1998), but it is occasionally used postoperatively for inoperable or recurrent cancers.
It may be given as a five-day or 25-day course.
A recent review (Krook et al, 1991) suggests that neo-adjuvant radiotherapy is particularly beneficial in reducing the risk of a local recurrence of rectal cancer within the pelvis.
The nursing care of patients having radiotherapy, which is usually delivered on an outpatient basis, includes the provision of adequate information on the effects and potential side-effects of this treatment, such as nausea, diarrhoea and local desquamation. Patients should be provided with written information and specialist nurses, doctors and radiographers should be the main contacts during this time.
The treatment of CRC varies depending on the site and pathological stage of the disease. Because it is usually detected at a relatively advanced stage, the prognosis is often poor: only 50% of patients survive for five years from the date of diagnosis.
The nursing care of patients with CRC should focus on the provision of information and psychological support to promote health and rehabilitation and, to a greater extent perhaps, bowel health promotion for the general population.
Colorectal cancers are common in the UK and colorectal nurse specialists are vital for the management of patients with CRC (NHS Executive, 1997; 2000). Generalist nurses, especially those in the surgical unit, need to have a sound knowledge of all treatment modalities to promote both the physical and psychological recuperation of patients with CRC.