Metastasis rare, survival high in cutaneous squamous cell carcinoma

Metastasis seems to be uncommon among patients with cutaneous squamous cell carcinoma (cSCC), though such risk may be higher among men, older patients, and those who are immunocompromised, a recent Dutch study has found. Disease-specific survival for metastatic cSSC (mCSSC) is high.

Drawing from the Netherlands Cancer Registry, researchers conducted a nationwide analysis, retrieving data for 11,137 patients who were diagnosed with first cSSC in 2007 or 2008. Over a median follow-up of 9.1 years, a total of 217 patients with mcSSC were confirmed. Most cases of metastases occurred within the first 4 years of diagnosis.

The overall cumulative incidence rate of mcSSC was just 1.9 percent over 10 years of follow-up, with an estimated time to occurrence of 1.5 years. Men saw a significantly higher mcSSC incidence rate than women (2.3 percent vs 1.4 percent; p<0.001).

Multivariable Cox proportional hazards analysis confirmed that men were slightly but significantly at greater risk of mcSSC (hazard ratio [HR], 1.7, 95 percent confidence interval [CI], 1.3–2.3), as were older patients, with each year of increasing age aggravating such risk by 3 percent (HR, 1.03, 95 percent CI, 1.02–1.05).

Notably, those who were immunocompromised saw a large increase in the risk of mcSSC, particularly those with haematologic malignancies (HR, 2.7, 95 percent CI, 1.6–4.6) and those who were organ transplant recipients (HR, 5.0, 95 percent CI, 2.5–10.0).

In terms of survival, researchers reported a 99.4-percent 5-year disease-specific survival. Overall survival was much lower at 69.8 percent, as most deaths could be attributed to other causes.