Abstract
Subcutaneous leiomyosarcoma is a rare, poorly understood variant of leiomyosarcoma. The current literature on the subject is sparse, consisting of isolated case reports and small clinicopathologic studies compromised by inclusion of its more common and less aggressive counterpart, cutaneous leiomyosarcoma. Thus, clinicopathologic characterization of this entity is limited. Cases of subcutaneous leiomyosarcoma (both in-house and consult material) reviewed from 1994 to 2022 were included in this retrospective study. A total of 29 cases were identified in our databases. A chi-squared test was used to determine statistical significance of findings unless otherwise stated. The mean age was 64 years, and the cohort was predominantly male (62%). Lesions averaged 4.0 cm in greatest dimension. The majority (93%) were diagnosed at an early pathologic stage (pT1 or pT2). Of the 24 cases with accessible clinical data and follow-up (mean 30 months, range 0-94 months), 5 (21%) were noted to have distant metastases at the time of diagnosis or during follow-up. These patients died of disease at an average of 41 months after diagnosis (range 3-94 months). Histologically, most tumors had a FNCLCC grade of either 1 or 2 (66%). A subset was noted to arise in association with a blood vessel (55%). Death from disease was significantly correlated with a higher T stage (p = 0.02) and the presence of necrosis (p = 0.02). Other trends associated with death from disease vs. survival included larger tumor size (6.0 vs. 3.9 cm; p = 0.18, Student’s t test), FNCLCC grade (p = 0.20), and association with a vessel (p = 0.27). Subcutaneous leiomyosarcomas are more aggressive than dermal-based tumors and have a prognosis intermediate to that of more aggressive deep-seated soft tissue leiomyosarcomas. Primary tumor stage and necrosis appear to be significantly associated with metastasis and death.
Financial Disclosure:
No current or relevant financial relationships exist.