Although squamous cell cancers of the skin can spread to the lymph nodes (or lymph glands) this is relatively unusual. The great majority of these tumours will be cured by the initial treatment with surgery or radiotherapy.
The lymph from the lower part of the leg drains into a cluster of lymph nodes at the back of the knee joint (these are called the popliteal lymph nodes). From there, the lymph drains into a chain of glands, which lie along the groin on the same side (these are known as the inguinal lymph nodes).
Normally it is impossible to feel your lymph glands, but if they become involved with seedlings of tumour then the glands will become firm and swollen. At this stage they can usually be felt quite easily through the skin. Although the glands may become enlarged it is unusual for them to be painful or tender to the touch if the swelling has been caused by spread of the cancer.
Lymph glands can become swollen for a number of different reasons and any infection in the leg would also cause them to become enlarged. When infection is present the glands are more likely to be sore and tender. So swelling of the lymph glands does not necessarily mean there is any cancer present.
So if you want to reassure yourself, feeling gently behind the knee and along the groin on your left side will check for any gland enlargement. Again I stress that this would be very unusual with your type of cancer. However, if you do find anything you are uncertain about then check with your GP, remembering it may well be an infection or some other condition rather than the cancer, which has caused the glands to swell.
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