Mohs micrographic surgery effective in high-risk cutaneous squamous cell carcinoma

Mohs micrographic surgery showed continued efficacy in preventing local recurrence and progression in high-risk cutaneous squamous cell carcinoma, according to a study.

“There is limited literature on the long-term outcomes and prognostic factors of high-risk cutaneous squamous cell carcinomas treated with Mohs micrographic surgery,” Andrew Matsumoto, MD, of the department of dermatology at the University of Texas Southwestern Medical Center in Dallas, and colleagues wrote.

In the current single institution, retrospective cohort analysis, the researchers aimed to assess rates of local recurrence, metastatic disease and disease-specific mortality in 882 patients (average age, 72.2 years; 87.6% men; 96.5% white) treated with Mohs surgery. Eligible participants had been treated with the Mohs procedure alone or with adjuvant therapy.

Patient and tumor-related factors with poor outcomes also underwent analysis.

The final analysis included 842 patients treated with Mohs micrographic surgery alone. These patients were followed for a median duration of 2.4 years.

The overall local recurrence rate for the full cohort was 2.5%. Metastatic disease occurred in 1.9%, while the disease-specific mortality rate was 0.57%.

Among patients with Brigham and Women’s stage T1 and T2a tumors treated with Mohs surgery alone, local recurrence rate was 1.6%, metastatic disease occurred in 1.3% and disease-specific death rate was 0.2%. For tumors stage T2b and above treated with Mohs surgery alone, local recurrence rate was 17.6%, while metastatic disease occurred in 17.6% and disease-specific mortality occurred in 5.9%.

The researchers also conducted a multivariate analysis to determine factors associated with progression. Immunosuppression (HR = 2.6; 95% CI, 1.2-7.8; P = .016), poor differentiation (HR = 7.2; 95% CI, 1.9-27.6; P = .0039) and perineural invasion (HR = 2.34; 95% CI, 0.5-10.2) were most associated with poor outcomes.

When the researchers conducted a propensity-score matched analysis for patients treated with adjuvant therapy versus those who underwent surgery alone, progression-free survival outcomes were comparable. They noted, however, that matching was “imperfect.”

“[Mohs micrographic surgery] remains an effective treatment for [high-risk cutaneous squamous cell carcinoma],” the researchers wrote. “Current [squamous cell carcinoma] staging systems may be limited by inconsistent inclusion of poor differentiation.”

They noted that immunosuppression — particularly among patients who have undergone transplantation — may elevate the likelihood of a poor outcome.