Cancer and the Foot

The fifth most common skin cancer is melanoma, according to the Marsden Hospital (London), but other forms of cancer exist, and the foot is as much a target as other parts of the body. The Mayo Clinic in the US suggests only 1% of cancers affect bone. Peeling information off the internet needs interpretation, and in reality, the foot is a low target for cancer. As a podiatrist, I have seen this mainly in the skin, but nail beds, the arch of the foot, and deeper tissues such as fat, nerves, and small blood vessels are prone, but not so much in bone or joints. Over 40 years of practice, this represents only a tiny percentage of cases. For any self-respecting clinician, you always have to ask yourself: how many potential cancers have I missed? 

Fortunately, working with a multi-disciplinary team, which included a local cancer centre in Birmingham, we saved most feet without amputation. We kept people alive for a long time after diagnosis. Before I qualified as a foot surgeon and could, therefore, undertake a biopsy to remove tissue for analysis, I relied on others to follow up on my clinical observations. Early detection with an ideal rapid referral of a suspicious tumour can increase the chances of recovery for patients.  However, specialist centres tend to be distributed widely in the UK, making the journey to and from any place for consultation less convenient.

Foot cancer is rare

This is not intended to be one of those scaremongering articles, but sometimes cancer does affect the foot. My most memorable case was where I was sent a nasty foot with a mushy ulcer that the patient’s GP thought was a verruca. This was a melanoma. The patient lived 5 years before succumbing to medical complications. Dermatoscopes are now used with ever-increasing popularity and, according to Dr Ivan Bristow, reduce the need for biopsy.  

A dermatoscope is a device for magnifying skin lesions to identify characteristics of abnormal change. It raises suspicions and increases the chances of earlier intervention. The literature tends to talk about other parts of the body rather than the foot being more common, and much of it gets tied in with the lower limb. Foot cancer can lead to early death, but I stress it is not common. Of 367,667 new cancers reported (2015-17) by Cancer Research, under 1/2 died of the disease. While this appears alarming, this statistic does not tell us what type of cancer kills most and where that cancer exists.

In the foot and from our experience, survival in the foot is better in most cases. A school friend had foot cancer in the sixties and lived with an amputation and prosthetic leg. It was not ideal, but he lived on to marry and, doubtless, have a full family. The link above shows the list and range of cancers, all with confusing names. Such names often relate to the type of tissue or location. It is worth looking at the words around cancer to de-mystify terms. 

Organs and Spread

Breast and ovarian cancer traditionally feature heavily in healthcare, with a renewed focus on bowel cancer for older patients with an upswing in prostate and testicular cancers for men.

These are not the only organs affected, as the skin, joints, and bones are still important human tissues that result in such abnormalities. The spread of cancers, carried through the lymphatics and blood, is called metastasis. The original sites of cancer are called Primaries, and where it is spread to another location, these are called Secondaries. Often, the Secondaries raise suspicions in feet after a bone breaks in the metatarsal bones, and this is where a bone or joint cancer may come to be recognised.

Who is At Risk?

Abnormal swellings are more prevalent in middle and older patients, although children can also be affected. Skin cancer not only affects fair-skinned or redheads. The pigmented type of tumour melanoma occurs in all races and affects all skin types and colours. Everyone is potentially at risk.

How come we miss some cancers?

‘A misdiagnosis of foot pain was made when this was actually related to the patient having lung cancer.  The patient was seen by two physicians and an orthopaedic surgeon who had missed the diagnosis when providing treatment.  The cancer sadly was detected too late.’ Shah-Hamilton

Pressures on the health system and the process of undertaking tick-list approaches to clinical examination can prevent clinicians from thinking outside the box. Cost cutting on diagnostic tests can also lead to missing cancers which might otherwise be picked up. The argument for podiatrists undertaking more work on cancer has never been more important, and the idea that this should rely on medical doctors alone in an area where the podiatrist is conversant with skin problems seems to miss the opportunity for better screening.

The message is clear. See your doctor if you are concerned, but you can see a specialist podiatrist (1) for an early opinion who can make that referral for you or can undertake tests. Even during COVID-19, it is important to push to see someone, and this may include a podiatrist. During COVID-19, I sought out help for a lesion on my face and wrote a piece about this in sun and skin. Many people in healthcare provide support for all types of cancer. Plastic surgeons reconstruct the anatomy affected. Orthopaedic surgeons who can help deal with bone and joint management: general surgeons and specialist surgeons for different organs as well as physicians. Doctors specialising in stabilising the body are oncologists.

What are the Key Types of Tumours?

Some tumours have a greater affinity for younger patients, e.g., sarcoma, although middle-aged adults typically present with this condition in their feet. Presentations can vary between patients. They might simply report pain instead of swelling. Testing for pain or swelling in the local lymph glands is important because the body filters and mops up infections and abnormal cell growths at these sites (armpit, groin, abdomen, chest, and neck). 

Tips for assessing lumps and bumps

If any of the following features are present as a suspicious growth – 

• lump size of more than 5cm
• a sudden increase in size
• a source of continual pain or discomfort
• change in colour
• bleeding without injury

It is important to remember that swelling is often harmless, but you should monitor any changes that take place, especially colour changes, bleeding, and pain. The toe nail is not an uncommon location for cancer in the foot. The hardened nail can change its appearance, and loss of the nail structure can be replaced with strange-shaped skin.  

A lady in her 70s wondered where her nail had gone, as it had an unusual appearance. I undertook a biopsy, removing a small piece of skin through the nail, and found this was a squamous cell carcinoma (2). This was not life-threatening, but she did have to lose a little bit of toe with her complete nail bed.

Pigments in the nail bed are more than likely due to an old blister that turned dark after injury—the pocket of blood changes colour from red to brown. Where there has been no known painful damage then it could be the shoe causing the blood to trap under the nail after a walk for instance. Always check that the pigment is not just a dye stain from the inside of your shoe. It should wipe off. However, where the pigment is dark and spreads, bleeds, maybe is painless, and the nail itself changes, or there is a long thin streak of dark pigment, this may be a type of cancer called a sub-ungual melanoma. Biopsy or taking a sample of the pigmented cell with normal skin is essential to classify its origin. I have biopsied many nails and nail beds, most are normal, but it is not easy to tell without a laboratory report. Today, the newer technique of diagnosing with a dermatoscope can reduce the need for some biopsying, and this is certainly to be recommended.

Supplementary facts and podiatry from Afni Shah-Hamilton

Five Conditions in feet caused by medication to treat cancers

How can podiatry help with peripheral neuropathy?
How can podiatrists help with the toxic effect of medication on nails?
How can podiatrists help with hand-foot syndromes?
How can podiatrists help with Xerosis?

[1] At present, podiatrists undertaking specialist work, known as extended scope practitioners, work in the NHS with multidisciplinary teams to triage urgency and offer some tests. Podiatric surgeons might offer biopsy tests depending on the presenting complaint and the risk. Referral to specialist centres is ideal for planning the holistic care of a patient  

 [2] A carcinoma forms in the skin or tissue cells that line the body’s internal organs, such as the kidneys and liver. A sarcoma grows in the body’s connective tissue cells, which include fat, blood vessels, nerves, bones, muscles, deep skin tissues and cartilage. This is a simplification but serves to differentiate the two common terms used.

Thanks for reading ‘Cancer and the Foot’, written by David Tollafield and Afni Shah-Hamilton. 

 

Busypencilcase Reflective Communications. First released in April 2020. Modified January 2025