A prognosis is a prediction of the outcome of one’s disease. How likely is survival? Will the cancer come back? These are the big questions on most people’s minds after receiving a diagnosis of skin cancer. In general, there are several characteristics of the tumor that can inform a patient about their chances of being cured.
Factors That Affect Prognosis
Stage
This is the most important factor that affects a patient’s chance of being cured.
Site
The location of the tumor can affect the surgeon’s ability to obtain negative margins and also affect the risk of spread to lymph nodes.
Type & Grade
Both the type and grade of the tumor determine the amount of treatment necessary and the ultimate prognosis.
Spread to Lymph Nodes
This helps determine stage, but even without other factors, spread to lymph nodes in the neck decreases the chance of cure, especially if there is evidence of growth of cancer outside of the lymph node.
Tumor Margins
The ability to completely remove the tumor with a margin of normal tissue around it can be a very important factor in a patient’s prognosis.
Depth of Invasion
The depth of a cancer’s growth into the skin can be an extremely important prognostic factor, especially in malignant melanoma.
Spread into Local Structures
Spread into large nerves, skin, and bone has been shown to indicate a worse prognosis.
While each of these factors contributes to one’s outcome, patients should have a discussion with their doctor to determine their overall prognosis. Giving a percentage of survival is challenging because cancer research often looks at multiple types of cancer and may include a large range of patients who underwent a variety of treatments.
Survival Rates for Patients with Specific Types of Skin Cancer
Prognosis for Basal Cell Carcinoma of the Skin
The factors associated with prognosis for basal cell carcinoma are discussed above, and they separate patients into low-risk and high-risk groups. In any case, the majority of BCCs are caught early, grow slowly and do not frequently invade deeply. Therefore, the cure rate is extremely high for most BCCs (up to 99 percent). However, there are rare basal cell carcinomas that are more aggressive and more likely to come back, invade deeply and spread to other parts of the body. Patients should speak to their doctor about their specific case if they have a more advanced basal cell carcinoma.
Prognosis of Squamous Cell Carcinoma of the Skin
The major prognostic factors associated with survival of SCC of the skin are accounted for in the staging system described above. Overall, advanced squamous cell carcinoma of the skin is quite rare. The majority of squamous cell carcinomas of the skin are caught early, in low stages, and are well treated with surgical removal. Patients should speak to their doctor about their specific case.
A large study from the Netherlands of almost 70,000 patients with invasive squamous cell carcinoma of the skin found that the five-year estimated disease-specific survival rate was 92 percent for men and 95 percent for women. Almost all of these patients were in Stage I (more than 50,000 patients). Even though less than 1.5 percent of patients were diagnosed in Stage III or Stage IV in this study, some prognostic data was still analyzed. They found that women diagnosed with a Stage III or IV SCC had a significantly worse prognosis compared to males (estimated disease-specific survival of 46 percent versus 62 percent). Their analysis by stage group found the following:
5-Year Estimated Disease-Specific Survival Rates
| Stage | Men | Women |
|---|---|---|
| Stage I | 95% | 98% |
| Stage II | 76% | 76% |
| Stage III/IV | 62% | 46% |
*Stage III and IV were combined in the survival analysis because there were too few examples in these categories to analyze separately.
Also, when looking at the site of the squamous cell carcinoma, the estimated disease-specific survival of males with an SCC on the scalp or neck (89 percent) was lower than that of an SCC on the lip (95 percent) and ear (93 percent).
Finally, while the AJCC staging system is important to predict survival, it does not allow for any patient (clinical) factors to be accounted for in the staging. For example, there is good data to suggest that immunosuppressed patients (organ transplant recipients, HIV carriers, leukemia, and lymphoma patients) have a slightly worse prognosis than those with an intact immune system.
Prognosis for Malignant Melanoma of the Skin
The following aspects of malignant melanoma of the skin may affect one’s prognosis. Again, this is a discussion patients should have with their doctor because every cancer is a little different.
Stage
The staging system is made to correlate with prognosis. Therefore, it is not a big surprise that stage of the cancer is related to the chances of survival. The lower the stage, the better the prognosis. This takes into account the size of the tumor and spread to other parts of the body, including lymph nodes, among a few other variables.
Thickness of the Tumor
This is the most important factor in predicting survival for melanoma. If the tumor is thin (less than 0.75 mm), the prognosis is quite good. However, tumors thicker than 4 mm have an estimated disease-specific survival rate of just under 50 percent at 10 years.
Anatomic Site
There is a hypothesis that lesions on visible parts of the skin do better than those in hidden parts. This may simply be because lesions in visible parts are detected at an earlier stage.
Type of Melanoma
Knowing the type of melanoma is important. For example, a superficial spreading melanoma has better prognosis than nodular or acral lentiginous melanoma.
Ulceration of the Tumor
Tumor ulceration is a diagnosis made under the microscope. It indicates that there is no completely intact epidermis above the primary melanoma. What we know is that for the same T-stage, a patient with an ulcerated melanoma does worse. Actually, their prognosis is pretty much the same as the next T-stage higher for a non-ulcerated melanoma.
It is very difficult to discuss prognosis without understanding all the details of the cancer, therefore this is a conversation patients are better off having in person with their doctor. In general, for patients with malignant melanoma, SEER data and AJCC show the following:
Comparison of Estimated Disease-Specific Survival Rate at 5 Years vs. 10 Years
| Stage | After 5 Years | After 10 Years |
|---|---|---|
| IA | 97% | 95% |
| IB | 92% | 86% |
| IIA | 81% | 67% |
| IIB | 70% | 57% |
| IIC | 53% | 40% |
| IIIA | 78% | 68% |
| IIIB | 59% | 43% |
| IIIC | 40% | 24% |
| IV | 15–20% | 10–15% |
Prognosis for Merkel Cell Carcinoma
The prognosis for Merkel cell carcinoma depends on a few factors, the most important being the stage at diagnosis:
Stage
The staging system is made to correlate with prognosis. Therefore, it is not a big surprise that stage of the cancer is related to the chances of survival. The lower the stage, the better the prognosis. This takes into account the size of the tumor and spread to other parts of the body, including lymph nodes, among a few other variables.
Immune Status
A number of studies have shown that patients who have compromised immune systems (such as in HIV/AIDS, chronic leukemia and transplant patients) do a little worse than healthier people.
According to SEER data, the 5-year estimated disease-specific survival rate for all stages is 63 percent, and the 10-year estimated disease-specific survival rate is 58 percent. Further analysis of the SEER data found that, based on whether or not the cancer has spread, the 10-year estimated disease-specific survival is as follows:
10-Year Estimated Disease-Specific Survival Rate
| Localized to Skin Area | 71% |
| Regional (Spread to Lymph nodes) | 48% |
| Distant (spread to distant parts of the body) | 20% |
When looking stage by stage based on the National Cancer Database (NCDB) statistics, we find the following:
5-Year Estimated Disease-Specific Survival by Stage
| Stage | Survival Rate |
|---|---|
| Stage IA | 79% |
| Stage IB | 60% |
| Stage IIA | 58% |
| Stage IIB | 49% |
| Stage IIC | 47% |
| Stage IIIA | 42% |
| Stage IIIB | 26% |
| Stage IV | 18% |
Disclaimer: Estimated Disease-Specific Survival is the percentage of people with a specific cancer who are alive at a given time point, such as five years after diagnosis. It excludes people who may have died from a disease other than their cancer. While these estimates from large national databases are helpful, it is important to remember that these broad statistics may not apply to one’s individual situation.
