Higher metastasis and death rates in cutaneous squamous cell carcinomas with lymphovascular invasion

Lymphovascular invasion (LVI) is an aggressive histologic finding but is excluded from current staging systems due to its lack of demonstrated independent prognostic significance.

To evaluate the impact of LVI on cutaneous squamous cell carcinoma tumor outcomes.

In total, 10,707 cutaneous squamous cell carcinoma tumors from a 20-year, retrospective, multicenter cohort were stratified by the presence (LVI⁺) or absence (LVI^-) of LVI. Outcomes (local recurrence, in-transit metastasis, nodal metastasis, disease-specific death) were compared based on low (Brigham and Women's Hospital [BWH] stage T1/T2a) and high (BWH T2b/T3) tumor stages.

Of the 10,707 tumors, 78 had LVI. The analysis of low-stage BWH tumors showed the LVI⁺ group had a significantly higher 5-year cumulative incidence of local recurrence (LVI⁺: 12.3%; LVI^-: 1.1%; P < .01), metastasis (LVI⁺: 4.2%; LVI^-: 0.4%; P < .01), and disease-specific death (LVI⁺: 16.2%; LVI^-: 0.4%; P < .01). The analysis of BWH high-stage tumors showed the LVI⁺ group maintained a higher 5-year cumulative incidence of metastasis (LVI⁺: 28.5%; LVI^-: 16.8%; P = .06) and disease-specific death (LVI⁺: 25.3%; LVI^-: 13.9%; P = .03), however, there was no difference in local recurrence (LVI⁺: 16.3%; LVI^-: 15.8%; P = .11).

Retrospective study design.

LVI⁺ cutaneous squamous cell carcinomas have higher rates of metastasis and death at 5 years. Future staging systems should consider incorporating LVI.