Staging cutaneous Squamous Cell Carcinoma (cSCC)

When all surgical and any imaging tests have been completed and pathology reports have been received, the doctors will try to figure out if the cancer has spread, and if so, how far. This process is called staging. It helps determine how serious the cancer is and how best to treat it.

A preliminary clinical stage is assigned after the physical examination and initial biopsy. The final pathology report determines the pathologic stage and helps to determine the treatment options. These two stages can be different, but importantly they will not change once they are defined. This is because the stage at diagnosis is important for evaluating treatment options, prognosis, and survival.

The stages of cSCC are based on several factors. The staging system used for cSCC of the head and neck is the American Joint Committee on Cancer (AJCC) TNM system, which is based on 3 key pieces of information:

T (tumour) What is the size and extent of the main tumour?
N (lymph node involvement) Has the cancer spread to nearby lymph nodes?
M (metastasis) Has the cancer spread to distant lymph nodes or distant organs?

Each letter is then assigned a numerical value which has more details about the cancer associated with it. The results of this analysis are grouped into five stages (0, I, II, III, and IV).

STAGES 0-IV

The staging system outlined below uses the pathologic stage. We have provided a simplified version of the latest TNM system as of January 2018. It is important to know that cSCC cancer staging can be complex. If you have any questions about the stage of your cancer or what it means for your treatment, ask your doctor to explain it in a way you understand.

cSCC has five stages: 0, I, II, III, IV

• Early cSCC is defined as stage I and stage II disease.
• Advanced cSCC is defined as stage III and stage IV disease.

Stage 0

  • The tumour has not spread beyond the top layer of the skin (epidermis). The cancer has not spread to nearby lymph nodes or distant organs.

Stage I

  • The tumour is smaller than or equal to 2 cm. The cancer has not spread to nearby lymph nodes or distant organs.

Stage II

  • The tumour is between 2 and 4 cm. The cancer has not spread to nearby lymph nodes or distant organs.

Stage III

Stage III cSCC is diagnosed if any of the following are true:

    • The tumour is larger than 4 cm.
    • The tumour has slightly worn away nearby bone (bone erosion).
    • The tumour has grown into or around nerves (perineural invasion).
    • The tumour has grown deep, past the fat under the skin (deep invasion).
    • The cancer has spread to 1 lymph node that is 3 cm or smaller.

Stage IV

  • Stage IV is diagnosed if there is substantial invasion of the bone, even in the absence of nodal involvement or distant metastases.
  • Stage IV is also diagnosed regardless of the size of the tumour if the cancer has spread to at least one lymph node that is larger than 3 cm.
  • Stage IV is also diagnosed regardless of tumour size or nodal involvement if the cancer has spread to distant organs (distant metastasis).