Lymphovascular Invasion and High Mitotic Count Are Associated With Increased Risk of Recurrence in Pleomorphic Dermal...

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Atypical fibroxanthoma and pleomorphic dermal sarcoma (PDS) are rare mesenchymal tumors.
• The true aggressiveness of PDS is poorly understood due to its low incidence and confusing nomenclature.
• This study aimed to identify clinical and histologic risk factors for PDS recurrence.

Purpose of the Study:

• To investigate clinical and histologic risk factors for recurrence in pleomorphic dermal sarcoma (PDS).
• To determine predictors of disease-free survival in PDS patients.

Main Methods:

• Retrospective, observational, bicentric study of 31 PDS cases (2005-2020).
• Clinical and histologic features were analyzed.
• Univariate and multivariate Cox regression analyses were performed.

Main Results:

• Univariate analysis showed tumor recurrence, necrosis, lymphovascular invasion, perineural invasion, and high mitotic count (≥18) were associated with worse disease-free survival.
• Multivariate Cox regression identified high mitotic count (≥18) and lymphovascular invasion as significant predictors of worse disease-free survival.

Conclusions:

• Pleomorphic dermal sarcoma (PDS) is an aggressive tumor.
• High mitotic count (≥18) and lymphovascular invasion are significant risk factors for recurrence and poorer disease-free survival.
• Necrosis and perineural invasion may also contribute to PDS aggressiveness.