Staging penile cancer

Your doctor will need to do some tests and scans to diagnose your cancer. Further tests will give some information about the stage of your cancer, which indicates how far a cancer has grown or spread. Staging is important because it helps the doctor recommend the most appropriate treatment for you.

The grade of a cancer measures how similar cancer cells are to normal cells when compared under a microscope. The general rule is the more a cancer cell looks like a normal cell, the lower the grade will be. The less it is like a normal cell, the higher the grade will be.

Establishing the grade of your cancer gives your doctors some idea of how your cancer is likely to behave. In penile cancer there are 4 grades, from 1 to 4. Grade 1 cancers (G1) are usually very slowly growing. Grade 4 cancers (G4) may grow more quickly.

• Gx means the grade cannot be assessed
• G1 means the cells look very like normal cells – they are called well differentiated or low grade
• G2 means the cells look unlike normal cells – they are called moderately differentiated
• G3 means the cells look very abnormal – they are called poorly differentiated or high grade
• G4 means the cells look completely unlike normal cells – they are called undifferentiated

There are different ways of staging cancers. The two main ways are

• The TNM system
• Number systems

Sometimes the stage of your cancer may sound a bit confusing. If you do not understand what stage your cancer is and would like to know more, ask your doctor. Understanding your staging may help you understand why your doctors have chosen a particular treatment for you.

There is a list of questions for your doctor at the end of this section that may help you. There is more general information about staging cancers in the section about cancer.

TNM stands for Tumour, Node, and Metastasis. The system describes

• The size of the primary tumour (T)
• Whether there are lymph nodes containing cancer cells (N)
• Whether the cancer has spread to a different part of the body

The size of the primary tumour (T)

The different T stages are

• T0 – no evidence of a tumour
• TX – the tumour can’t be assessed
• Tis or carcinoma in situ – this is the earliest stage of penile cancer, when the cancer cells are only inside of the lining of the penis and have not grown into any surrounding tissues or spread
• Ta – the cancer is wart like or verrucous and is not deep into the tissue, or spread to another part of the body
• T1a – the tumour affects the connective tissue, which is the layer of tissue just under the skin and is low grade
• T1b – the tumour affects the connective tissue and surrounding blood vessels and is high grade (grade 3 and 4)
• T2 – the tumour affects the spongy erectile tissue in the penis
• T3 – the tumour has grown into the urethra
• T4 – the cancer has invaded other nearby parts of the body such as the prostate gland

Whether there are lymph nodes containing cancer cells (N)

The N stage refers to whether any lymph nodes (glands) contain cancer cells.

• N0 – no lymph nodes contain cancer cells
• N1 – one lymph node under the skin in the groin (inguinal) contains cancer cells
• N2 – two or more lymph nodes in the groin contain cancer cells
• N3 – the cancer has spread through the outer layer of a lymph node and into surrounding tissue, or has spread to lymph nodes in the pelvis

Whether the cancer has spread to a different part of the body (M)

The M stage refers to any spread of the cancer (secondary cancers, or metastases) to other organs in the body.

• M0 – there are no metastases or secondary cancers in the body
• M1 – the cancer is affecting another part or parts of the body, such as the liver or the lungs

Occasionally doctors use a number system to stage your cancer. These usually have a scale of 1 to 4, as below

Stage 1

The cancer affects the surface or skin of the penis, the head of the penis or the foreskin. But it has not spread anywhere else in the body. This is the same as T1a, N0, M0.

Stage 2

The cancer has invaded or spread deeper into the head of the penis or is affecting the shaft of the penis (the columns of erectile tissue) and may have grown into the urethra. This is the same as T1b, T2 or T3 and N0, M0.

Stage 3 is divided into two stages

Stage 3a means that the cancer is affecting the penis and a single lymph node in the groin. It has not spread to more distant parts of the body. This is the same as T1–3, N1, M0.

Stage 3b means the cancer is affecting the penis and there are cancer cells in 2 or more of the lymph nodes in the groin. It has not spread to other parts of the body. This is the same as T1–3, N2, M0.

Stage 4

This can be any of the following

• The cancer is deep into the penis and has spread to the lymph nodes, but has not spread to other parts of the body (T4, N1–3, M0)
• The cancer is affecting the penis and may have grown outside a lymph node into surrounding tissue or has spread to the lymph nodes in the pelvis. It has not spread to other parts of the body (T1–3, N3, M0)
• The cancer is affecting the penis, it may affect the lymph nodes and has spread to another part of the body (any T, any N, M1)