Penile Cancer: Diagnosis

Approved by the Cancer.Net Editorial Board, 02/2023

ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, cancer. They also do tests to learn if cancer has spread to another part of the body from where it started. If the cancer has spread, it is called metastasis. Doctors may also do tests to learn which treatments could work best.

For most types of cancer, a biopsy is the only sure way for the doctor to know if an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.

How penile cancer is diagnosed

There are different tests used for diagnosing penile cancer. Not all tests described here will be used for every person. Your doctor may consider these factors when choosing a diagnostic test:

  • The type of cancer suspected

  • Your signs and symptoms

  • Your age and general health

  • The results of earlier medical tests

In addition to a physical examination, the following tests may be used to diagnose penile cancer:

  • Biopsy. If there is an unusual change on or in the penis or nearby lymph nodes, a biopsy may be needed to learn more about the change. A biopsy is the only way to make a definite diagnosis, even if other tests can suggest that cancer is present. During biopsy, a small amount of tissue is removed for examination under a microscope. A pathologist analyzes the sample(s). A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease.

    If cancerous cells are seen in a tissue sample, then the biopsy is called positive for cancer. If no cancer is found, then the biopsy is called benign or negative for cancer. Sometimes, the pathologist cannot tell if the cells collected are cancerous, which means the biopsy is called indeterminate or non-diagnostic.

    The following types of biopsies may be used for penile cancer:

    • A punch biopsy or elliptical excision may be used for an abnormal change that can be seen on the penis. In a punch biopsy, the doctor uses a sharp round surgical tool to remove a circular piece of tissue. In an elliptical excision, the doctor uses a scalpel or other tool to cut out a piece of tissue.

    • A fine needle aspiration is a specific type of biopsy. First, the skin is usually made numb with a topical medication applied on the skin that blocks the sensation of pain. Then, a medication is injected into the area near the tumor to prevent pain in tissues beneath the skin. The doctor will then insert a thin needle into the tumor and remove some cells and fluid. The procedure may be repeated 2 or 3 times to collect samples from different areas of the tumor.

    • A sentinel lymph node biopsy is a way to find out if cancer cells have spread to lymph nodes near the penis. In this technique, the doctor removes 1 or a few sentinel lymph nodes to check for cancer cells. The doctor may recommend using imaging scans and dyes to aid with the biopsy. If this is done, it is called a dynamic sentinel node biopsy (DSNB). Lymph nodes are the small, bean-shaped organs that help fight infection. They are connected to each other by tiny vessels called lymphatic vessels. Sentinel lymph nodes are the first lymph node(s) into which the lymph fluid from the tumor drains. If there are multiple lymph vessels draining the area where the tumor is located, then there may be more than 1 sentinel lymph node. For penile cancer, the sentinel lymph nodes are located just under the skin in the groin. If cancer cells are found in these lymph nodes, it means that the cancer is more likely to have spread to other nearby lymph nodes or to other parts of the body. Even if cancer cells are not found during a sentinel lymph node biopsy, there is still a chance that the cancer has spread.

  • Inguinal (groin) lymph node dissection. This is the most accurate way to find out whether the cancer has spread to any lymph nodes near the penis. It may be recommended if certain risk factors for spread are present or if there are enlarged lymph nodes on physical exam or imaging studies. In this procedure, the lymph nodes near the penis are removed and checked for cancer. This procedure provides more information than the removal of a single lymph node or a group of lymph nodes. However, after this procedure, there may be problems with wound healing, as well as long-lasting and possibly severe leg swelling, called lymphedema. Research to find ways to prevent these side effects is ongoing (see Latest Research).

  • X-ray. An x-ray creates a picture of the structures inside of the body using a small amount of radiation.

  • Computed tomography (CT or CAT) scan. A CT scan takes pictures of the inside of the body using x-rays taken from different angles. A computer combines these pictures into a detailed, 3-dimensional image that shows abnormalities or tumors. A CT scan can be used to measure a tumor’s size. Sometimes, a special dye called a contrast medium is given before the scan to provide better detail on the image. This dye can be injected into a patient’s vein or given as a pill or liquid to swallow. A CT scan helps find out if the cancer has spread to lymph nodes in the groin, pelvis, and the abdomen. It also allows the doctor to see if the cancer has spread to the lungs, liver, and other tissues.

  • Magnetic resonance imaging (MRI). An MRI produces detailed images of the inside of the body using magnetic fields, not x-rays. MRI can be used to measure the tumor’s size. A special dye called a contrast medium is given before the scan to create a clearer picture. This dye can be injected into a patient’s vein or given as a pill or liquid to swallow.

  • Positron emission tomography (PET) or PET-CT scan. A PET scan creates pictures of organs and tissues inside the body. A PET scan is usually combined with a CT scan (see above), called a PET-CT scan. However, you may hear your doctor refer to this procedure just as a PET scan. A small amount of a radioactive sugar substance is injected into the patient’s body. This sugar substance is taken up by cells that use the most energy. Because cancer tends to use energy actively, it absorbs more of the radioactive substance. However, the amount of radiation in the substance is too low to be harmful. A scanner then detects this substance to produce images of the inside of the body.

  • Ultrasound. An ultrasound creates a picture of the internal organs using sound ways. It may be used as an alternative if other imaging methods are not available.

After diagnostic tests are done, your doctor will review the results with you. If the diagnosis is cancer, these results also help the doctor describe the cancer. This is called staging.

The next section in this guide is Stages and Grades. It explains the system doctors use to describe the extent of the disease. Use the menu to choose a different section to read in this guide.