Cancer Care (Nursing and Health Survival Guides), 1e

Staging and grading of cancer

When a person has been diagnosed with cancer they are usually told what stage the cancer is: this is a measure of how much the cancer has grown and spread. Grading refers to specific characteristics of the cancer cells: generally the earlier the stage and the lower the grade of the cancer, the better the prognosis.

STAGING

Staging helps the patient and the clinician decide upon the most appropriate management of the disease and how well it might respond to treatment. An international staging system is the most commonly used system for most adults presenting with solid tumours – this is known as the TNM system.

• T for tumour – how far the primary tumour has grown locally (tumour extension).

• N for nodes – if there is spread to the local lymph nodes (lymph node dissemination).

• M for metastases – if there is spread to other parts of the body (distant tumour spread).

After a cancer has been staged, a number is given for each of the three characteristics. In a man with stomach cancer, for example, the following could apply:

The TNM system:

• allows clinicians to assess a person’s prognosis

• ensures that all healthcare professionals are using a standardised system

• can be seen as providing a bench mark on which to make further judgment

The table below gives a fuller explanation of the TNM system that can be applied to most cancers; this is how you may see other healthcare professionals documenting or discussing the staging of the cancer.

Below is a diagrammatic representation of a TNM classification for a colon cancer.

Dysplasia

Understandably, patients may be very anxious after they have been given a diagnosis of cancer and as soon as possible after initial diagnosis they should be told about the stage of their cancer. Investigations will be carried out to determine the stage and during this time the nurse should:

• offer support to the patient and their family

• make referrals to appropriate organisations, for example, Macmillan

You are already aware that the TNM staging system is commonly used with adults with solid tumours. Other types of classifications exist and are used, for example, for malignant melanoma: a scale called the ‘primary tumour thickness scale’, also known as the Breslow thickness.

Haematological tumours are not solid tumours and the TNM classification is unsuitable due to the systematic nature of these malignancies. Other classification systems are used, for example:

STAGING AND INVESTIGATIONS

After a diagnosis a number of tests and investigations will be needed to determine the stages. The type of investigation or test will vary subject to the cancer and may include blood tests and scans. The range of investigations falls into three key groups:

• radiology

• pathology

• endoscopy

Radiology

Using radiological investigation allows for visualisation of internal body structures. A number of X-rays (gamma rays) are used to generate an image of the body, for example, a mammogram. Sometimes a contrast medium is used, for example, if an image of the gastro intestinal tract is required the patient will be asked to swallow a contrast medium that enhances the structures of the gastro intestinal tract.

• Computerised Tomography Scan (CT Scan)

• Magnetic Resonance Imaging (MRI)

• Ultrasound

• Positron Emission Tomography (PET)

Pathology

Pathological tests include tests on body fluids, for example, blood and urine. Biochemical tests can confirm normal or abnormal levels of various chemicals, for example, alkaline phosphate. Tumour markers (usually proteins) are produced by a tumour or by the body as it makes a response to cancer. There are some tumour markers that will only be produced by one type of cancer; others can be made by many cancer types. Some markers can be found in cancerous and non-cancerous conditions.

A biopsy can be used for histological examination; this is analysed microscopically to determine if the cells are normal or cancer cells. Sometimes biopsies are able to tell where in the body a cancer has started. In some types of cancer it is virtually impossible to diagnose cancer any other way.

Endoscopy and surgery

Endoscopy may be needed to enable samples of suspected cancerous tissue to be retrieved for analysis. The figure shows a colonoscopy.

Colonoscopy

Endoscopies can include:

• gastroscopy

• colonoscopy

• cystoscopy

• hysteroscopy

Surgical intervention may be needed to look inside the deeper cavities or a difficult to reach part or parts of the body. There are times when a cancer cannot be accurately staged until an operation has been performed to remove the primary tumour. The tissues removed with the tumour are analysed to see how far the cancer cells have grown through the normal tissues and whether nearby lymph nodes contain cancer cells.

The nurse has an important role to play in all of the above investigations offering support to the patient before, during and after the investigation. Some of the investigations discussed require specific pre-investigation preparation, for example:

• The patient needs to be nil by mouth for a gastroscopy.

• Jewellery and metal objects need to be removed for certain scans.

• An enema or bowel preparation may be needed for some bowel investigations.

An opportunity must be given for the patient to ask any questions if they are unsure or are seeking clarification.

GRADING AND INVESTIGATIONS

Grading can occur after biopsy, for instance, after microscopic examination or testing in other ways, for example, through cytological testing. In the laboratory certain features of the cells can be observed and the cancer can be graded as low, intermediate or high.

• Low-grade cancers are often slow-growing and can appear similar to normal cells (are well differentiated). These cells are often less aggressive and they are less likely to spread quickly.

• Intermediate-grade is a middle grade.

• High-grade suggests that the cancer cells are fast growing, they look very abnormal (poorly differentiated), are likely to be more aggressive and usually spread quickly.

• Breast cancers are graded 1, 2 or 3 similar to low-grade, intermediate-grade and high-grade.

• Prostate cancer is graded by Gleason score; this is similar to other grading systems, a low Gleason score means much the same as low-grade and a high Gleason score means much the same as high-grade.

The stage and the grade are used together to advise about the various treatment options and when discussing prognosis.

SECTION SUMMARY

It is important to grade and classify the type of cancer (if possible). This informs treatment and provides an opportunity to discuss prognosis. Patients will be understandably anxious when diagnosed with cancer and will often ask how far advanced it is. Staging and grading allows clinicians to answer this question.

The most common classificatory system for adult solid tumours is the TNM system. For non-solid tumours, i.e. haematological tumours, other systems exist.

There are several types of tests and investigations needed to classify the stage of cancer. The nurse has a role to play in helping patients understand these tests and to ensure that they are safely prepared and cared for before, during and after the procedure.

Grading of the tumour occurs when the cells are analysed: cells are observed to determine what their features are. The cancer can then be graded as low, intermediate or high grade.

Fill in the table below regarding the care of a patient undergoing the specific investigation prior to the procedure, during the procedure and after the procedure. You should consider the physical, legal and psychological aspects of care.